Re: [bolger] Re: Laminating plywood
On Sun, Feb 7, 2010 at 7:51 AM, etap28<dave.irland@...>wrote:around here (Western MA) Home Depot rules, unfortunately. To the detriment of any serious lumber outfit.
A la Junebug, even 15 years ago I bet BC pine was better than it is now.. and when I think WAY back, AC ply was perfectly good for boats, even "serious" ones (if you didn't mind that it does't finish very well, and checks like crazy). Cut off those ends, make a Tortoise out of it!!
My son and I went to Menards today and picked up four sheets of 3/4" A/C Arauco on sale for $24 a sheet, plus there was an additional 10% discount for using a Menards card. My son said the C side of the panels looked more like a B side. The radiata pine plantations use fixed tree spacings and prune all the trees so the plies that are peeled off are very regular with few knot holes.
Above the Arauco was a bunch of treated southern pine plywood. My son said, what is that ugly stuff. I said treated plywood is always ugly, but difference with the two panels side by side was quite dramatic.
Regarding my deceased Junebug, it's the middle that rotted and the ends are OK. I've been thinking of putting in an 8 foot long Tortoise section in the middle and joining it to the ends. Maybe I should make it bolt together in three pieces, so I could have one long boat or two shorter ones.
Fred
Very good info Doug, thanks for the videos. Regards, Jeff --- OnSun, 2/7/10, Doug Jackson<svseeker@...>wrote:
|
We recently tested Georgia Pacific AC from Lowes against marine grade at over 3 times the cost. While the marine grade was better in some test, a sample that had been wet for 54 days actually did worse than the common plywood under the same conditions.
We have a two part video of the testing. We also tested epoxy and construction adhesives. Anybody thinking of using Liquid Nails should watch.
Part 1http://www.youtube.com/watch?v=_ymEoivrrK0
Part 2http://www.youtube.com/watch?v=IY7hkCexNVY
Best of Luck
Doug
"I began life as a bad boy." --Simon Lake, father of the modern submarine
Join "Bad Boy Submarines" at ArgonautJr.com
________________________________
From: etap28 <dave.irland@...>
To:bolger@yahoogroups.com
Sent: Sun, February 7, 2010 7:51:24 AM
Subject: [bolger] Re: Laminating plywood
around here (Western MA) Home Depot rules, unfortunately. To the detriment of any serious lumber outfit. I built an Auray Punt out of some of that Sureply stuff and it was sub-par, the boat was used out of doors for about 10 years and started falling apart in the middle of those 10 years, which was a shame because I didn't build it to throw away. I got great service out of it (daily use, 2 to 4 miles round trip to a boat I lived on) but still, maybe it's the yankee in me, I hate to see a boat I really like just disappear for no reason but crap plywood. If I'd spend an extra $100 when I built it I'd still have that boat, and it was the Best Darn Dinghy I ever had.
So... not a believer is scrimping, even when the boat's not a huge time investment
A la Junebug, even 15 years ago I bet BC pine was better than it is now.. and when I think WAY back, AC ply was perfectly good for boats, even "serious" ones (if you didn't mind that it does't finish very well, and checks like crazy). Cut off those ends, make a Tortoise out of it!!
We have a two part video of the testing. We also tested epoxy and construction adhesives. Anybody thinking of using Liquid Nails should watch.
Part 1http://www.youtube.com/watch?v=_ymEoivrrK0
Part 2http://www.youtube.com/watch?v=IY7hkCexNVY
Best of Luck
Doug
"I began life as a bad boy." --Simon Lake, father of the modern submarine
Join "Bad Boy Submarines" at ArgonautJr.com
________________________________
From: etap28 <dave.irland@...>
To:bolger@yahoogroups.com
Sent: Sun, February 7, 2010 7:51:24 AM
Subject: [bolger] Re: Laminating plywood
around here (Western MA) Home Depot rules, unfortunately. To the detriment of any serious lumber outfit. I built an Auray Punt out of some of that Sureply stuff and it was sub-par, the boat was used out of doors for about 10 years and started falling apart in the middle of those 10 years, which was a shame because I didn't build it to throw away. I got great service out of it (daily use, 2 to 4 miles round trip to a boat I lived on) but still, maybe it's the yankee in me, I hate to see a boat I really like just disappear for no reason but crap plywood. If I'd spend an extra $100 when I built it I'd still have that boat, and it was the Best Darn Dinghy I ever had.
So... not a believer is scrimping, even when the boat's not a huge time investment
A la Junebug, even 15 years ago I bet BC pine was better than it is now.. and when I think WAY back, AC ply was perfectly good for boats, even "serious" ones (if you didn't mind that it does't finish very well, and checks like crazy). Cut off those ends, make a Tortoise out of it!!
--- In bolger@yahoogroups. com, Fred Schumacher <fredschum@. ..> wrote:
>
> On Sat, Feb 6, 2010 at 9:48 AM, etap28 <dave.irland@ ...> wrote:
>
> >
> >
> > Who's Menards? Sounds interesting.
> >
> > You're right about boats not being expected to last forever way back when,
> > but in the Olden Days, the people who built them were considered disposable,
> > too, and wood seemed inexhaustible.
> >
>
> Menards is a regional discount lumber yard chain out of Eau Claire,
> Wisconsin. They're all over the Midwest and are something like Home Depot,
> except they have better lumber and house building supplies, in general.
>
> Some 15 years ago, I built Junebug out of B/C pine. It was criminal the way
> I mistreated her, and this past year the center of her succumbed to rot. If
> I had been even a little bit more careful, she would have been OK. I'm
> thinking of cutting off the ends and building a new middle to make a longer
> boat. (We've all gotten heavier with age.) But she only cost me $200, so
> that's less than $15 per year. You can't beat that.
>
> Has anybody had any experience with Arauco radiata pine plywood? The sheets
> I got show no voids in any of the edges, so that's usually a good sign. It's
> A/C plywood.
>
> Fred
>
around here (Western MA) Home Depot rules, unfortunately. To the detriment of any serious lumber outfit. I built an Auray Punt out of some of that Sureply stuff and it was sub-par, the boat was used out of doors for about 10 years and started falling apart in the middle of those 10 years, which was a shame because I didn't build it to throw away. I got great service out of it (daily use, 2 to 4 miles round trip to a boat I lived on) but still, maybe it's the yankee in me, I hate to see a boat I really like just disappear for no reason but crap plywood. If I'd spend an extra $100 when I built it I'd still have that boat, and it was the Best Darn Dinghy I ever had.
So... not a believer is scrimping, even when the boat's not a huge time investment
A la Junebug, even 15 years ago I bet BC pine was better than it is now.. and when I think WAY back, AC ply was perfectly good for boats, even "serious" ones (if you didn't mind that it does't finish very well, and checks like crazy). Cut off those ends, make a Tortoise out of it!!
So... not a believer is scrimping, even when the boat's not a huge time investment
A la Junebug, even 15 years ago I bet BC pine was better than it is now.. and when I think WAY back, AC ply was perfectly good for boats, even "serious" ones (if you didn't mind that it does't finish very well, and checks like crazy). Cut off those ends, make a Tortoise out of it!!
--- Inbolger@yahoogroups.com, Fred Schumacher <fredschum@...> wrote:
>
> On Sat, Feb 6, 2010 at 9:48 AM, etap28 <dave.irland@...> wrote:
>
> >
> >
> > Who's Menards? Sounds interesting.
> >
> > You're right about boats not being expected to last forever way back when,
> > but in the Olden Days, the people who built them were considered disposable,
> > too, and wood seemed inexhaustible.
> >
>
> Menards is a regional discount lumber yard chain out of Eau Claire,
> Wisconsin. They're all over the Midwest and are something like Home Depot,
> except they have better lumber and house building supplies, in general.
>
> Some 15 years ago, I built Junebug out of B/C pine. It was criminal the way
> I mistreated her, and this past year the center of her succumbed to rot. If
> I had been even a little bit more careful, she would have been OK. I'm
> thinking of cutting off the ends and building a new middle to make a longer
> boat. (We've all gotten heavier with age.) But she only cost me $200, so
> that's less than $15 per year. You can't beat that.
>
> Has anybody had any experience with Arauco radiata pine plywood? The sheets
> I got show no voids in any of the edges, so that's usually a good sign. It's
> A/C plywood.
>
> Fred
>
Thanks, David. That's about right. It did stand a week long soak in cold. For my 'what I've got on hand' kayak, well painted and with the bottom covered in dacron, I'm able to risk the local sloughs where if I fall out I can stand right up.
Again, I would not build anything very substantial from it. Arauco would be much superior.
On Feb 6, 2010, at 6:26 PM, dnjost wrote:
Mark -
I tried the boil method and dishwasher method on several squares of Sureply. It delaminated in 5 minutes. Be careful here...
David Jost
"waiting for a warm day here and there"
Mark -
I tried the boil method and dishwasher method on several squares of Sureply. It delaminated in 5 minutes. Be careful here...
David Jost
"waiting for a warm day here and there"
I tried the boil method and dishwasher method on several squares of Sureply. It delaminated in 5 minutes. Be careful here...
David Jost
"waiting for a warm day here and there"
Oops. Before offending, let me correct it's is not 'Superply' I
commented on, rather the 5.2mm 'Sureply' Luan underlayment found at
Home Depot et al.
Mark
commented on, rather the 5.2mm 'Sureply' Luan underlayment found at
Home Depot et al.
Mark
so when a guy builds something in the 21st century, it sort of hurts to see rot set in 10 years down the road, whereas a three masted coasting schooner that died in 10 years wasn't that big of a deal in 1870 since the average life span of a boat carpenter was about 40 years,
Call it 'economy decent.' Mine came from a real lumberyard as exactly the modern equivalent of the old a/c. The glue is good and it works nicely. A bit harder than fir. Cutting in did not reveal huge voids. Not much heavier than fir.
By comparison, I'm trying the Superply now, one of few alternatives at the price. ( Watch any batch of that for some very sloppy stuff tho. ) Also the glue on the better looking sheets I've is not as good as the Arauco. It holds back cold water, but is very thin. While in all a fair, light duty 5 ply, SP's skins are so thin I was nervous about stitch & gluing it and certainly wouldn't contemplate anything very large with what I've seen.
In two worlds so well described, plantation pine from Chile seems inevitable.
On Feb 6, 2010, at 1:52 PM, Fred Schumacher wrote:
On Sat, Feb 6, 2010 at 9:48 AM, etap28<dave.irland@ gmail.com>wrote:
Has anybody had any experience with Arauco radiata pine plywood? The sheets I got show no voids in any of the edges, so that's usually a good sign. It's A/C plywood.
Fred.
On Sat, Feb 6, 2010 at 9:48 AM, etap28<dave.irland@...>wrote:Who's Menards? Sounds interesting.
You're right about boats not being expected to last forever way back when, but in the Olden Days, the people who built them were considered disposable, too, and wood seemed inexhaustible.
Menards is a regional discount lumber yard chain out of Eau Claire, Wisconsin. They're all over the Midwest and are something like Home Depot, except they have better lumber and house building supplies, in general.
Some 15 years ago, I built Junebug out of B/C pine. It was criminal the way I mistreated her, and this past year the center of her succumbed to rot. If I had been even a little bit more careful, she would have been OK. I'm thinking of cutting off the ends and building a new middle to make a longer boat. (We've all gotten heavier with age.) But she only cost me $200, so that's less than $15 per year. You can't beat that.
Has anybody had any experience with Arauco radiata pine plywood? The sheets I got show no voids in any of the edges, so that's usually a good sign. It's A/C plywood.
Fred
Who's Menards? Sounds interesting.
You're right about boats not being expected to last forever way back when, but in the Olden Days, the people who built them were considered disposable, too, and wood seemed inexhaustible. These days people who build boats have to make way more money to compensate their much higher standards of living and longer life spans and income taxes and general inflation, and the materials are far more precious than ever before, both due to corporate profiteering and the shortages of good wood, so when a guy builds something in the 21st century, it sort of hurts to see rot set in 10 years down the road, whereas a three masted coasting schooner that died in 10 years wasn't that big of a deal in 1870 since the average life span of a boat carpenter was about 40 years, and there were lots of them, and wood was almost free
BUT--the big caveat, I do think the standard of wooden boats has gotten ridiculously high in some cases. That Skimmer built by Nexus... holy cow. That's like a 400 yr. boat
PS I thought Chapelle on Friendship Sloop construction was pretty amazing stuff
You're right about boats not being expected to last forever way back when, but in the Olden Days, the people who built them were considered disposable, too, and wood seemed inexhaustible. These days people who build boats have to make way more money to compensate their much higher standards of living and longer life spans and income taxes and general inflation, and the materials are far more precious than ever before, both due to corporate profiteering and the shortages of good wood, so when a guy builds something in the 21st century, it sort of hurts to see rot set in 10 years down the road, whereas a three masted coasting schooner that died in 10 years wasn't that big of a deal in 1870 since the average life span of a boat carpenter was about 40 years, and there were lots of them, and wood was almost free
BUT--the big caveat, I do think the standard of wooden boats has gotten ridiculously high in some cases. That Skimmer built by Nexus... holy cow. That's like a 400 yr. boat
PS I thought Chapelle on Friendship Sloop construction was pretty amazing stuff
--- Inbolger@yahoogroups.com, Fred Schumacher <fredschum@...> wrote:
>
> On Fri, Feb 5, 2010 at 7:56 AM, etap28 <dave.irland@...> wrote:
>
> >
> >
> >
> > I agree about the false economy of trying to use cheap Home Depot stuff...
> >
>
> Menards has been selling Arauco Chilean plantation grown radiata pine
> plywood, and it is beautiful looking stuff, nothing like the southern pine
> you normally find available. I looked up the mechanical characteristics, and
> it's quite close to Douglas fir, including, unfortunately, rot resistance,
> which is low, but then okoume is also low in rot resistance. I bought 16
> sheets of half inch (5 ply) at $20 each and three sheets of three-quarter
> inch at $24 each for a boat I'm designing for the Wooden Boat contest. At
> that price, there's not much risk. I've got a bunch of left over epoxy, and
> we'll cover the outside with epoxy garage floor paint, so this will be a
> cheap project. People never used to expect boats to last forever, our cars
> don't last forever, nothing does. Better to build than to wait for
> perfection.
>
Sorry on library time here so this may be a repeat.
"After looking at the site where the guy vacuum bags the Black Skimmer, I
"conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger"
Th first layer has to go down conventionally and flat, no little concave pooches or hard spots and it needs to be air tight, within reason. You need to have the plywood run wild several inches, but more is better, all around the boat, though possibly not in the middle since that will tend to get pressed down. You still need a flange of some sort all around. The sheet you are putting on top are probably better if they are scarphed into one piece, but if they aren't they need to be super limp or they won't press down. You still need scarphs between the sheet but don't sweat them they can be a little rough, The feather edge is the key since the vac will not hold down a hard edge if low pressure. This is all the scoop on low pressure. High pressure gives you a little more error room on clamping pressure but you loose out on air volume, so the leak patrol is more critical. I have three pumps, but I use the shop vac on all plywood sheet jobs. I spread clear epoxy on both sides of the sheets, and use the thickened stuff only to fill potential voids. Even the thick stuff is a little soupy so it can float around and fill stuff in.
You secure the sheet by caulking around the perimeter well outside of the line where the new layer will go down, and it in turn needs to be outside the edge of the boat bottom. The issue is that the perimeter will not glue down on a vac bagged shop vac boat, the first 2" is not going to glue down. But so long at you cut that off the rest will be awesome. It takes the clamping pressure of outboard material to form the best bond, so the edges need to run oversize a little, or be made of cloth, you can put a top layer of biaxial on flush to the edges.
You can use some thickened epoxy in areas you think bay be pround but the approach given works every time. Your bag is just construction plastic, 6 mil, dropped over the caulking as a single sheet.
"issue is a reliable vacuum source. Running a shop vac against its full load
capability means little air moving thorugh it. That means a great potential for
overheating."
It means a certainty it will burn out in a few minutes. You drill 4 1/4" holes in the hose (or use a sliding port thing), so that fresh air pulls through, that will ensure the motor lasts for hundreds, or thousands, of hours.
A tool worth having is a cheap vac gage, only a few bucks. Mount it in the end cap for some 4" PVC pipe. You cut a hole in your bag, drop the gage over it and place reusable putty like duxseal around the perimeter. This gage will read out around 2 pounds with a vac cleaner. But that still means like 188 pounds of pressure per foot. You can test the gauge by just puttung the vac hose directly to it. The gauge is useful for determining how many holes to drill. You can drill as many as you like and stop only when the pressure takes a drop. Because of the high volume of air moved through a vac cleaner, the pressure will stay up there with enough air going through to cool the motor.
" If less than its full vacuum will clamp suffiicently, I"d be
tempted to install a valve that would introduce some air, and/or water for
cooling the 'pump'."
You got it. Vac cleaners have been responsible for some awesome registered catamarans. The incredible thing about vac is to see it work in the first place, then you realize it works just as well on a 70 footer as a 7 footer, probably better. Try that with a single screw or hand clamp.
Vac wise get the smallest cheapest shopvac, though I would spring for quiet, QSP, or whatever they call it. Clean it out so that you don't have junk in there that obstructs the ventilation. I had one that cost 30 buck when we weren't getting stuff from China, and it lasted through many boats, only packing it in when I vacced up a drywall job without sufficient filtration.
You can seem my boat vac set-up here:
http://www.themultihull.com/kh/td1.htm
Bubble wrap for difusion, and a drilled hose as the manifold
"After looking at the site where the guy vacuum bags the Black Skimmer, I
"conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger"
Th first layer has to go down conventionally and flat, no little concave pooches or hard spots and it needs to be air tight, within reason. You need to have the plywood run wild several inches, but more is better, all around the boat, though possibly not in the middle since that will tend to get pressed down. You still need a flange of some sort all around. The sheet you are putting on top are probably better if they are scarphed into one piece, but if they aren't they need to be super limp or they won't press down. You still need scarphs between the sheet but don't sweat them they can be a little rough, The feather edge is the key since the vac will not hold down a hard edge if low pressure. This is all the scoop on low pressure. High pressure gives you a little more error room on clamping pressure but you loose out on air volume, so the leak patrol is more critical. I have three pumps, but I use the shop vac on all plywood sheet jobs. I spread clear epoxy on both sides of the sheets, and use the thickened stuff only to fill potential voids. Even the thick stuff is a little soupy so it can float around and fill stuff in.
You secure the sheet by caulking around the perimeter well outside of the line where the new layer will go down, and it in turn needs to be outside the edge of the boat bottom. The issue is that the perimeter will not glue down on a vac bagged shop vac boat, the first 2" is not going to glue down. But so long at you cut that off the rest will be awesome. It takes the clamping pressure of outboard material to form the best bond, so the edges need to run oversize a little, or be made of cloth, you can put a top layer of biaxial on flush to the edges.
You can use some thickened epoxy in areas you think bay be pround but the approach given works every time. Your bag is just construction plastic, 6 mil, dropped over the caulking as a single sheet.
"issue is a reliable vacuum source. Running a shop vac against its full load
capability means little air moving thorugh it. That means a great potential for
overheating."
It means a certainty it will burn out in a few minutes. You drill 4 1/4" holes in the hose (or use a sliding port thing), so that fresh air pulls through, that will ensure the motor lasts for hundreds, or thousands, of hours.
A tool worth having is a cheap vac gage, only a few bucks. Mount it in the end cap for some 4" PVC pipe. You cut a hole in your bag, drop the gage over it and place reusable putty like duxseal around the perimeter. This gage will read out around 2 pounds with a vac cleaner. But that still means like 188 pounds of pressure per foot. You can test the gauge by just puttung the vac hose directly to it. The gauge is useful for determining how many holes to drill. You can drill as many as you like and stop only when the pressure takes a drop. Because of the high volume of air moved through a vac cleaner, the pressure will stay up there with enough air going through to cool the motor.
" If less than its full vacuum will clamp suffiicently, I"d be
tempted to install a valve that would introduce some air, and/or water for
cooling the 'pump'."
You got it. Vac cleaners have been responsible for some awesome registered catamarans. The incredible thing about vac is to see it work in the first place, then you realize it works just as well on a 70 footer as a 7 footer, probably better. Try that with a single screw or hand clamp.
Vac wise get the smallest cheapest shopvac, though I would spring for quiet, QSP, or whatever they call it. Clean it out so that you don't have junk in there that obstructs the ventilation. I had one that cost 30 buck when we weren't getting stuff from China, and it lasted through many boats, only packing it in when I vacced up a drywall job without sufficient filtration.
You can seem my boat vac set-up here:
http://www.themultihull.com/kh/td1.htm
Bubble wrap for difusion, and a drilled hose as the manifold
I think your advice is sound. However Bolger had suggested roofing tar/cement and bronze nails for some of the larger designs. This includes the house boat Illinois.
Don
Don
--- Inbolger@yahoogroups.com, "otter55806" <otter55806@...> wrote:
>
> Just use epoxy. If any of these cheaper options were any good designers such as Bolger, and professional builder, such as Devlin, would use them. Experimenting on a very small, super cheap throw away may be OK but false ecomnomy on anything else. The lamanated (two half inch layers) bottom, and everything else, on my Micro Trawler are fine after 16 years; and so is my Bantam after 5 years.
> Epoxy is tried and true.
> Bob
>
Amen! I would fit the steel including drilling holes and fitting carriage bolts to hold it securely to the bottom. Then I'd take the steel to a galvanizer, and have it hot dip galvanized. Finally, I'd mask off the hull sides AND interior (holes in the bottom) and paint the bottom with a generous coating of roofing tar, considering having a pro apply HOT tar. Then immediately drop the steel bottom on and set the bolts in their holes, washer and nuts from the inside. Messy? You bet. Long lasting? For sure.
Don
Don
--- Inbolger@yahoogroups.com, "adventures_in_astrophotography" <jon@...> wrote:
>
> I've been thinking that roofing tar would make a great bedding compound for the steel belly armour on some of PB&F's more recent designs. It's got to be cheaper than the 3M 5200 specified, though perhaps messier.
>
> Jon Kolb
> www.kolbsadventures.com
>
On Fri, Feb 5, 2010 at 7:56 AM, etap28<dave.irland@...>wrote:
I agree about the false economy of trying to use cheap Home Depot stuff...
Menards has been selling Arauco Chilean plantation grown radiata pine plywood, and it is beautiful looking stuff, nothing like the southern pine you normally find available. I looked up the mechanical characteristics, and it's quite close to Douglas fir, including, unfortunately, rot resistance, which is low, but then okoume is also low in rot resistance. I bought 16 sheets of half inch (5 ply) at $20 each and three sheets of three-quarter inch at $24 each for a boat I'm designing for the Wooden Boat contest. At that price, there's not much risk. I've got a bunch of left over epoxy, and we'll cover the outside with epoxy garage floor paint, so this will be a cheap project. People never used to expect boats to last forever, our cars don't last forever, nothing does. Better to build than to wait for perfection.
I agree about the false economy of trying to use cheap Home Depot stuff...
I once built a skiff out of CDX and it leaked THROUGH the wood. This was a quick one-off scalloping skiff and it was November so I ended up drying the wood on the beach with a blow torch and then spreading roofing tar.... which worked, more or less.
But anyway--boats demand a better grade of stuff, it's just a fact of life. though a flat bottomed skiff, very low labor costs, and used in the open air (no enclosed compartments) in salt water can last a long time built out of exterior grade ply and dimensional lumber a la the Brockway Skiffs and all the home made scalloping boats around the Cape that sit in salt ponds on stern lines with 2x4 gunwhales
I once built a skiff out of CDX and it leaked THROUGH the wood. This was a quick one-off scalloping skiff and it was November so I ended up drying the wood on the beach with a blow torch and then spreading roofing tar.... which worked, more or less.
But anyway--boats demand a better grade of stuff, it's just a fact of life. though a flat bottomed skiff, very low labor costs, and used in the open air (no enclosed compartments) in salt water can last a long time built out of exterior grade ply and dimensional lumber a la the Brockway Skiffs and all the home made scalloping boats around the Cape that sit in salt ponds on stern lines with 2x4 gunwhales
--- Inbolger@yahoogroups.com, "otter55806" <otter55806@...> wrote:
>
> Just use epoxy. If any of these cheaper options were any good designers such as Bolger, and professional builder, such as Devlin, would use them. Experimenting on a very small, super cheap throw away may be OK but false ecomnomy on anything else. The lamanated (two half inch layers) bottom, and everything else, on my Micro Trawler are fine after 16 years; and so is my Bantam after 5 years.
> Epoxy is tried and true.
> Bob
>
>
> --- Inbolger@yahoogroups.com, "daschultz2000" <daschultz8275@> wrote:
> >
> >
> > Glad the plans arrived. Were these from PB&F, or 2nd hand?
> >
> > My concern about using PL would be getting coverage to100%. Any 'holidays' as Bolger called them, in the coverage would be potential trouble. One of the other powder/water mix glues may make more sense, and be even less $$. One might also consider polyester resin for this particular joint, but use epoxy with glass for the panel to panel seams. Hmmm, I may like that best of all.
> >
> > After looking at the site where the guy vacuum bags the Black Skimmer, I conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger issue is a reliable vacuum source. Running a shop vac against its full load capability means little air moving thorugh it. That means a great potential for overheating. If less than its full vacuum will clamp suffiicently, I"d be tempted to install a valve that would introduce some air, and/or water for cooling the 'pump'.
> >
> > Don
> >
> > --- Inbolger@yahoogroups.com, Ron Badley <sn1834@> wrote:
> > >
> > >... P.S. Got my Dakota plans!
> > >
> >
>
> The simplest, most reliable, and perhaps cheapest way to laminate theI totally agree with Chris, epoxy and ring nails is super easy, cheap,
> plywood is with epoxy and bronze ring nails. That's the way I've done
> it, and it is foolproof and easy.
fast and effective.
Here are some photos of me doing it with my Topaz bottom:
http://hallman.org/webcam/I/hour54.html
One of the downsides of dealing with Bolger-loving types is that they
think that they should be free to re-invent the wheel, and they often
invent octagon drums and oval pullies.
The simplest, most reliable, and perhaps cheapest way to laminate the
plywood is with epoxy and bronze ring nails. That's the way I've done
it, and it is foolproof and easy.
You can think about using other kinds of glue, but I assure you that PL
Premium is NOT cheaper than epoxy (the unit you purchase is smaller),
and is it significantly more difficult to work with.
You want an excellent result that's easy to pull off?
0. Do not does this on the shop floor, instead, do the laminating IN
PLACE on the boat. This way there is no resistance to bending built into
the now-thick sheet.
1. Mix up some unthickened, slow-hardenered epoxy, and put it on both
surfaces, with a squeegee (and a foam brush to help).
2. Mix up some more slow-hardenered epoxy, but this time mix in some
fumed silica (e.g., cab-o-sil) and milled/chopped fiberglass fibers
(e.g., "cat hair"). Distribute this evenly (and thinly) with squeegee or
notched trowel.
3. Gently mate the surfaces, starting at one end (as you would do with,
say, contact cement). Begin nailing at that end, using bronze ring nails
that are thinner than your combined plies (don't cut it too close,
here), working methodically toward the other end. Be careful that excess
epoxy does not splatter.
4. Clean off your edges, and wait.
5. Once done, seal your ply edges (I prefer epoxy and tape), and enjoy
your boat, knowing that the lamination will not fail, nor will it allow rot.
-Chris
think that they should be free to re-invent the wheel, and they often
invent octagon drums and oval pullies.
The simplest, most reliable, and perhaps cheapest way to laminate the
plywood is with epoxy and bronze ring nails. That's the way I've done
it, and it is foolproof and easy.
You can think about using other kinds of glue, but I assure you that PL
Premium is NOT cheaper than epoxy (the unit you purchase is smaller),
and is it significantly more difficult to work with.
You want an excellent result that's easy to pull off?
0. Do not does this on the shop floor, instead, do the laminating IN
PLACE on the boat. This way there is no resistance to bending built into
the now-thick sheet.
1. Mix up some unthickened, slow-hardenered epoxy, and put it on both
surfaces, with a squeegee (and a foam brush to help).
2. Mix up some more slow-hardenered epoxy, but this time mix in some
fumed silica (e.g., cab-o-sil) and milled/chopped fiberglass fibers
(e.g., "cat hair"). Distribute this evenly (and thinly) with squeegee or
notched trowel.
3. Gently mate the surfaces, starting at one end (as you would do with,
say, contact cement). Begin nailing at that end, using bronze ring nails
that are thinner than your combined plies (don't cut it too close,
here), working methodically toward the other end. Be careful that excess
epoxy does not splatter.
4. Clean off your edges, and wait.
5. Once done, seal your ply edges (I prefer epoxy and tape), and enjoy
your boat, knowing that the lamination will not fail, nor will it allow rot.
-Chris
On Thu, Feb 4, 2010 at 6:26 AM, otter55806 <otter55806@...> wrote:
Buehler is a highly respected boat designer and boat builder and he
advocates for the use of 'tar' bituminous builders roof patch compound
as boat building adhesive.
>I personally use epoxy. That said, it is hard to deny that George
>
>
> Just use epoxy. If any of these cheaper options were any good designers such as Bolger,
> and professional builder, such as Devlin, would use them.
Buehler is a highly respected boat designer and boat builder and he
advocates for the use of 'tar' bituminous builders roof patch compound
as boat building adhesive.
On a boat with a flat bottom made of laminations of construction plywood, I agree that roofing tar/cement can be used with great success. I would want permanent mechanical fasteners AND glass sheathing along with the tar for the lamination joint. I believe the full "cure time" of that joint may be measured in months if not years.
When I was looking to buy a small mountain of CDX or maybe MDO and start building a Bolger "ILLINOIS", I thought it likely I could build the bottom structure including the laminated box keel that formed the primary structure of the boat by gluing the bottom most panel with epoxy, and then adding the additional laminations to it with roofing tar. I would have hired a roofer to supply hot tar for the effort, and also used stainless staples to mechanically secure the additional panels. Once the basic keel had 'setup' I was going to add 1x8 to the sides of hte box keel to cover the edge grain of the plywood. That would also have been stainless screws or staples and tar, then multiple coats of epoxy on the outside of that.
Tar would fill gaps, be extremely waterproof, flex without cracking, get stronger with age.
Don Schultz
When I was looking to buy a small mountain of CDX or maybe MDO and start building a Bolger "ILLINOIS", I thought it likely I could build the bottom structure including the laminated box keel that formed the primary structure of the boat by gluing the bottom most panel with epoxy, and then adding the additional laminations to it with roofing tar. I would have hired a roofer to supply hot tar for the effort, and also used stainless staples to mechanically secure the additional panels. Once the basic keel had 'setup' I was going to add 1x8 to the sides of hte box keel to cover the edge grain of the plywood. That would also have been stainless screws or staples and tar, then multiple coats of epoxy on the outside of that.
Tar would fill gaps, be extremely waterproof, flex without cracking, get stronger with age.
Don Schultz
Just use epoxy. If any of these cheaper options were any good designers such as Bolger, and professional builder, such as Devlin, would use them. Experimenting on a very small, super cheap throw away may be OK but false ecomnomy on anything else. The lamanated (two half inch layers) bottom, and everything else, on my Micro Trawler are fine after 16 years; and so is my Bantam after 5 years.
Epoxy is tried and true.
Bob
Epoxy is tried and true.
Bob
--- Inbolger@yahoogroups.com, "daschultz2000" <daschultz8275@...> wrote:
>
>
> Glad the plans arrived. Were these from PB&F, or 2nd hand?
>
> My concern about using PL would be getting coverage to100%. Any 'holidays' as Bolger called them, in the coverage would be potential trouble. One of the other powder/water mix glues may make more sense, and be even less $$. One might also consider polyester resin for this particular joint, but use epoxy with glass for the panel to panel seams. Hmmm, I may like that best of all.
>
> After looking at the site where the guy vacuum bags the Black Skimmer, I conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger issue is a reliable vacuum source. Running a shop vac against its full load capability means little air moving thorugh it. That means a great potential for overheating. If less than its full vacuum will clamp suffiicently, I"d be tempted to install a valve that would introduce some air, and/or water for cooling the 'pump'.
>
> Don
>
> --- Inbolger@yahoogroups.com, Ron Badley <sn1834@> wrote:
> >
> >... P.S. Got my Dakota plans!
> >
>
Hi Rick,
Jon Kolb
www.kolbsadventures.com
> Then there is roofing tar. Has anyone tried this on a plywood hull bottom?I've been thinking that roofing tar would make a great bedding compound for the steel belly armour on some of PB&F's more recent designs. It's got to be cheaper than the 3M 5200 specified, though perhaps messier.
>
> I know in the past I've had a devil of a time trying to pry apart two layers of plywood on a roof that were held together with only roofing tar.
Jon Kolb
www.kolbsadventures.com
Now that's good thinking
Harry James wrote:
Harry James wrote:
PL Premium a Polyurethane Construction Adhesive in a tube. I have used it when I use AC ply and stainless staples, Latex paint for instant boat construction. Probably would work for this use but a Clam skiff is too big a project ie too many man hours to use cheap materials. I draw the line at 50 hrs, if I am putting in that amount of effort then I want it to last. I built this EP with a staple gun and PL premium and it lasted 31/2 seasons, gave it away to some kids on the dock in Pelican last summer when it started leaking.http://tritonclass.org/mir/144ta5.jpgHJ Bill Howard wrote:What is PL? On Feb 3, 2010, at 2:42 AM, KevinA.Donohue wrote:Can you get your panels tight enough with screws and washers for PL to work? *From:* Ron Badley<mailto:sn1834@...>*Sent:* Tuesday, February 02, 2010 10:50 PM *To:*bolger@yahoogroups.com<mailto:bolger@yahoogroups.com>*Subject:* [bolger] Laminating plywood Regarding laminating up several layers of plywood for thick bottom panels on Bolger power sharpies. Epoxy is the obvious, and expensive, choice. What about using PL? Has anyone tried it on a larger boat? False economy? RonB. P.S. Got my Dakota plans!------------------------------------ Bolger rules!!! - NO "GO AWAY SPAMMER!" posts!!! Please! - no cursing, flaming, trolling, spamming, respamming, or flogging dead horses - stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts - Pls add your comments at the TOP, SIGN your posts, and snip away - Plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349 - Unsubscribe:bolger-unsubscribe@yahoogroups.com- Open discussion:bolger_coffee_lounge-subscribe@yahoogroups.comYahoo! Groups Links <*> To visit your group on the web, go to:http://groups.yahoo.com/group/bolger/<*> Your email settings: Individual Email | Traditional <*> To change settings online go to:http://groups.yahoo.com/group/bolger/join(Yahoo! ID required) <*> To change settings via email:bolger-digest@yahoogroups.combolger-fullfeatured@yahoogroups.com<*> To unsubscribe from this group, send an email to:bolger-unsubscribe@yahoogroups.com<*> Your use of Yahoo! Groups is subject to:http://docs.yahoo.com/info/terms/
| I'd add a notched trowel to the toolkit for this operation. Even better than a notched trowel is one of those springy combs. I recently bought one 12" wide, looks like a cross between a lawn rake and a drywall tapers knife. I think it was designed for spreading mastic for tile work, but it sure does a nice job of evenly distributing the epoxy spread by the drywall knife. Rick --- OnWed, 2/3/10, Bruce Hallman<hallman@...>wrote:In my experience laminating up the |
| Then there is roofing tar. Has anyone tried this on a plywood hull bottom? I know in the past I've had a devil of a time trying to pry apart two layers of plywood on a roof that were held together with only roofing tar. --- OnWed, 2/3/10, John Huft<t1ro2003@...>wrote: |
Check Grainger.com for vacuum pumps. These can run for days at a time. My late uncle used this process in painting restoration. In his case, the bonding agent was wax.
I am still concerned about the process when using epoxy. The epoxies I have used would crack when the panel is flexed. I recall a recent thread about the comparative brittleness of a variety of brands. IIRC, MAS stays pliable for days. It may have been on the Selway-Fisher group.
Another concern is the amount of sheer between the various panels when they are flexed after laminating on the flat. The referenced Black Skimmer Photos are a fiberglass on plywood lamination. The cloth has little thickness and can stretch. Two plywood panels will definitely try to shift when they are flexed.
I am still concerned about the process when using epoxy. The epoxies I have used would crack when the panel is flexed. I recall a recent thread about the comparative brittleness of a variety of brands. IIRC, MAS stays pliable for days. It may have been on the Selway-Fisher group.
Another concern is the amount of sheer between the various panels when they are flexed after laminating on the flat. The referenced Black Skimmer Photos are a fiberglass on plywood lamination. The cloth has little thickness and can stretch. Two plywood panels will definitely try to shift when they are flexed.
> After looking at the site where the guy vacuum bags the Black Skimmer, I conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger issue is a reliable vacuum source. Running a shop vac against its full load capability means little air moving thorugh it. That means a great potential for overheating. If less than its full vacuum will clamp suffiicently, I"d be tempted to install a valve that would introduce some air, and/or water for cooling the 'pump'.
>
> Don
It has a kind of like creamy peanut butter consistency. I don't think it passes the boiling water part of the test but then if I'm in a plywood boat in boiling water I think I'd be worried about something else.
John Boy
John Boy
From:Ron Badley <sn1834@...>
To:bolger@yahoogroups.com
Sent:Wed, February 3, 2010 9:31:17 AM
Subject:Re: [bolger] Laminating plywood
Hey Guys,
Sounds like epoxy is the best, least risky, choice.
Yes, the plans came from PB&F.
PL is poly ...something. House construction subfloor adhesive.
Waterproof-ish, but quite think.
RonB.
PL Premium a Polyurethane Construction Adhesive in a tube. I have used
it when I use AC ply and stainless staples, Latex paint for instant boat
construction. Probably would work for this use but a Clam skiff is too
big a project ie too many man hours to use cheap materials. I draw the
line at 50 hrs, if I am putting in that amount of effort then I want it
to last. I built this EP with a staple gun and PL premium and it lasted
31/2 seasons, gave it away to some kids on the dock in Pelican last
summer when it started leaking.
http://tritonclass.org/mir/144ta5.jpg
HJ
Bill Howard wrote:
it when I use AC ply and stainless staples, Latex paint for instant boat
construction. Probably would work for this use but a Clam skiff is too
big a project ie too many man hours to use cheap materials. I draw the
line at 50 hrs, if I am putting in that amount of effort then I want it
to last. I built this EP with a staple gun and PL premium and it lasted
31/2 seasons, gave it away to some kids on the dock in Pelican last
summer when it started leaking.
http://tritonclass.org/mir/144ta5.jpg
HJ
Bill Howard wrote:
>
>
> What is PL?
> On Feb 3, 2010, at 2:42 AM, KevinA.Donohue wrote:
>
>>
>>
>> Can you get your panels tight enough with screws and washers for PL
>> to work?
>>
>>
>> *From:* Ron Badley <mailto:sn1834@...>
>> *Sent:* Tuesday, February 02, 2010 10:50 PM
>> *To:*bolger@yahoogroups.com<mailto:bolger@yahoogroups.com>
>> *Subject:* [bolger] Laminating plywood
>>
>>
>>
>> Regarding laminating up several layers of plywood for thick bottom
>> panels on Bolger power sharpies. Epoxy is the obvious, and expensive,
>> choice. What about using PL? Has anyone tried it on a larger boat?
>> False economy?
>>
>> RonB.
>>
>> P.S. Got my Dakota plans!
>>
>>
>
>
>
>
On my first boat, a Bolger June Bug, I experimented with several glues, Weldwood Plastic Resin, Epoxy and Weldwood Resorcinol. Weldwood Plastic was the least expensive. I used it for laminating my mast. I used epoxy on the butt joints.
I would use Weldwood Plastic Resin for any joints or laminating dimension lumber. I believe epoxy would be supreior for laminating plywood because of its gap filling properties. Weldwood Plastic Resin does not fill gaps.
I found Resorcinol to be more expensive, harder to mix, and generally messier than Plastic resin.
On Feb 3, 2010, at 11:10 AM, Steve Rose wrote:I'd lean more towards Weldwood Plastic Resin Glue than PL, it has a good track record with boat building and is much nicer to work with in my opinion than the epoxies and it's less money
____________ _________ _________ _________ _________ _________ _
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I'd lean more towards Weldwood Plastic Resin Glue than PL, it has a good track record with boat building and is much nicer to work with in my opinion than the epoxies and it's less money
__________________________________________________________________
Connect with friends from any web browser - no download required. Try the new Yahoo! Canada Messenger for the Web BETA athttp://ca.messenger.yahoo.com/webmessengerpromo.php
__________________________________________________________________
Connect with friends from any web browser - no download required. Try the new Yahoo! Canada Messenger for the Web BETA athttp://ca.messenger.yahoo.com/webmessengerpromo.php
Hey Guys,
Sounds like epoxy is the best, least risky, choice.
Yes, the plans came from PB&F.
PL is poly ...something. House construction subfloor adhesive.
Waterproof-ish, but quite think.
RonB.
Sounds like epoxy is the best, least risky, choice.
Yes, the plans came from PB&F.
PL is poly ...something. House construction subfloor adhesive.
Waterproof-ish, but quite think.
RonB.
On Tue, Feb 2, 2010 at 10:50 PM, Ron Badley <sn1834@...> wrote:
topic of "large hull laminating panels" from six weeks back. There is
plenty of advice available here. In my experience laminating up the
30 foot long bottom of a Topaz, I was very happy with the ease and
economy of using generic epoxy spread with a wide "drywall knife", and
squeezing the panels together tightly with silicon bronze ring shank
nails.
>You might also want to check the discussion similar thread on the
>
>
> Regarding laminating up several layers of plywood for thick bottom
> panels
topic of "large hull laminating panels" from six weeks back. There is
plenty of advice available here. In my experience laminating up the
30 foot long bottom of a Topaz, I was very happy with the ease and
economy of using generic epoxy spread with a wide "drywall knife", and
squeezing the panels together tightly with silicon bronze ring shank
nails.
Glad the plans arrived. Were these from PB&F, or 2nd hand?
My concern about using PL would be getting coverage to100%. Any 'holidays' as Bolger called them, in the coverage would be potential trouble. One of the other powder/water mix glues may make more sense, and be even less $$. One might also consider polyester resin for this particular joint, but use epoxy with glass for the panel to panel seams. Hmmm, I may like that best of all.
After looking at the site where the guy vacuum bags the Black Skimmer, I conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger issue is a reliable vacuum source. Running a shop vac against its full load capability means little air moving thorugh it. That means a great potential for overheating. If less than its full vacuum will clamp suffiicently, I"d be tempted to install a valve that would introduce some air, and/or water for cooling the 'pump'.
Don
My concern about using PL would be getting coverage to100%. Any 'holidays' as Bolger called them, in the coverage would be potential trouble. One of the other powder/water mix glues may make more sense, and be even less $$. One might also consider polyester resin for this particular joint, but use epoxy with glass for the panel to panel seams. Hmmm, I may like that best of all.
After looking at the site where the guy vacuum bags the Black Skimmer, I conclude it isn't that tough to vacuum bag a flat bottom design. IMO the bigger issue is a reliable vacuum source. Running a shop vac against its full load capability means little air moving thorugh it. That means a great potential for overheating. If less than its full vacuum will clamp suffiicently, I"d be tempted to install a valve that would introduce some air, and/or water for cooling the 'pump'.
Don
--- Inbolger@yahoogroups.com, Ron Badley <sn1834@...> wrote:
>
>... P.S. Got my Dakota plans!
>
What is PL?
On Feb 3, 2010, at 2:42 AM, KevinA.Donohue wrote:Can you get your panels tight enough with screws and washers for PL to work?Regarding laminating up several layers of plywood for thick bottom
panels on Bolger power sharpies. Epoxy is the obvious, and expensive,
choice. What about using PL? Has anyone tried it on a larger boat?
False economy?
RonB.
P.S. Got my Dakota plans!
I'm not sure if it would work. I think you'd need something with good gap filling qualities. Is PL viscus enough to spread over the entire surface and gap filling enough to bond when there is a slight gap between the laminations? You'll end up with tight spots under the screws and loose spots between the screws. I've looked at some studies that shows laminated ply is not as strong as factory ply, that is two layers of 1/2 inch versus one layer of 1 inch but that's internet facts so who knows. I tend to think you'd be better off with a think coating of slow cure epoxy thickened up with wood flour or micro balloons.
I did see a website where the builder, a pro, used vacuum bagging for the second layer on a Black Skimmer. More time and money but tight clamping over the entire surface.
John Boy
I did see a website where the builder, a pro, used vacuum bagging for the second layer on a Black Skimmer. More time and money but tight clamping over the entire surface.
John Boy
From:KevinA.Donohue <kadonohue@...>
To:bolger@yahoogroups.com
Sent:Wed, February 3, 2010 1:42:52 AM
Subject:Re: [bolger] Laminating plywood
Can you get your panels tight enough with screws and
washers for PL to work?
Regarding laminating up several layers of plywood for thick bottom
panels
on Bolger power sharpies. Epoxy is the obvious, and expensive,
choice. What
about using PL? Has anyone tried it on a larger boat?
False
economy?
RonB.
P.S. Got my Dakota plans!
Can you get your panels tight enough with screws and
washers for PL to work?
Regarding laminating up several layers of plywood for thick bottom
panels
on Bolger power sharpies. Epoxy is the obvious, and expensive,
choice. What
about using PL? Has anyone tried it on a larger boat?
False
economy?
RonB.
P.S. Got my Dakota plans!
Regarding laminating up several layers of plywood for thick bottom
panels on Bolger power sharpies. Epoxy is the obvious, and expensive,
choice. What about using PL? Has anyone tried it on a larger boat?
False economy?
RonB.
P.S. Got my Dakota plans!
panels on Bolger power sharpies. Epoxy is the obvious, and expensive,
choice. What about using PL? Has anyone tried it on a larger boat?
False economy?
RonB.
P.S. Got my Dakota plans!
Thanks. The "e" is important!
On Jan 31, 2010, at 11:09 PM, eric14850 wrote:Here is a link to a LOTS of pictures of boats sporting junk rigs.http://images. google.com/ images?hl= en&um=1&q= junk+rig& sa=N&start= 0&ndsp=21
http://www.kastenma rine.com/ junk_rig. htm
shows his take off on the junk rig A euphroe would replace the fiddle block. Because a euphroe is just a slat of wood with holes the lines pass through it has a lot of resistance. the sheet can be adjusted to pull more on one batten than another. From Kasten: "Sail shape is controlled by the sheets mainly. Each "sheetlet" runs through a "euphroe" which acts as friction block to keep the tension set as intended. In my drawing, I've made use of a simpler arrangement using a fiddle block and separate "lizard" eyes in order to allow the sail to self adjust when it is reefed."
From Wikipedia: "On a
traditional Chinese junk rig, the sail is controlled by
sheetlets -- small sheet lines running from the battens to
blocks that in turn are on lines running through a
euphroe, a long piece of wood with holes in it. This helps
maintain uniform tension in each panel of the sail." Sheetlets are the line loops from one batten down to the next.
And here is what I was looking for halfway down the page:
http://www.dragonvo yage.com/ ship/rig. shtml
Western designers starting with Hastler and then Colvin followed by others have made modifications of the Junk rig. Bolger took some aspects of the junk rig and created a modern multi-yard gaff rig. Some on this forum have been (I think) referring to this as Bolger's Chinese Junk rig. It is not. The junk rig is a lug rig, and though Bolger liked the lug rig, he did not like the Chinese lug rig very much, though he respected Hastler and others who did like it. Bolger did design at least one boat that I am aware of that had the option of a Chinese Junk rig. 35'+- barge hull if I remember correctly.
Eric
--- Inbolger@yahoogroups. com, Bill Howard <billh39@... > wrote:
>
> Google never heard of euphros. What are they?
> On Jan 31, 2010, at 7:59 PM, eric14850 wrote:
>
> > The nice thing about a small and not too serious boat is one can experiment with it without it costing too much, or anyone taking the experiment too seriously.
> >
> > Even to windward the plastic tarp is pulling quite well. :-)
> > And there are several things wrong with this set up.
> > He uses battens which are not nearly stiff enough. The wind is not blowing very hard and the battens are curved. They should be stiff enough to be straight. The mainsheet is probably not led far enough aft. The designer Tom Colvin typically uses two sheets to each junk sail with the sheets attached about a fifth of the way forward of the leech on each side of the sail to deal with this problem. It does mean using a lot of line and handling two lines to control one sail. Colvin also states emphatically to resist the urge to use blocks in place of euphros. One wants the resistance a euphro provides and a block does not in order to set the sail properly. A properly set junk sail will have each batten in a line virtually parallel to the mast, or just the slightest twist at the top where the wind is stronger. Only the bottom three battens of the blue tarp are set correctly.
> >
> > Fun to experiment with, the junk sail is best suited to situations where safety requires all sail handling to be done from the cockpit or control station (Jester), to safely/easily handle a large sail (especially reefing), or to make inadequate sailmaterial adequate to the job of motivating a boat in all sailing weather, including the ability to sail to windward.
> >
> > On a small boat with the possibility of good sail cloth, the balanced lug will set far better than this junk sail was setting, and will, in my experience (using an old mainsail (too flat a cut to be ideal) with a yard taking the place of the top third of the sail) a well set balanced lug sail is capable of pointing just as high and motivating a boat just as fast as modern fin keel high masted sloops of similar size. In 25mph gusting to 35mph winds (finally winds strong enough to fill the eight oz sailcloth!) ROGUE outsailed the few other boats of similar size, and most that were larger on the lake, and kept up with a well sailed racer/cruiser that club races twice a week and is a few feet longer than ROGUE. That boat was crewed, I sailed alone. Once tacked, ROGUE was capable of sailing itself, so, as with the other boats, I strolled up to the mainmast to enjoy the scenery including the other boat's attempts to trim sails more effectively, while Rogue sailed itself. So much for the innate superiority of the modern sloop. Furthermore, at the time ROGUE's leeboards were only partially lowered. My guess is we could easily have sailed in three feet of water. None of the other boats could have followed us into such shallow water. Raising the leeboards would have allowed me to sail in these winds in even shallower water.
> >
> > Eric
> >
> > --- Inbolger@yahoogroups. com, "steve" <stevepallen@ > wrote:
> > >
> > > I came across this on a meander,
> > >
> > >http://www.keepturn ingleft.co. uk/keepturningle ft.php?type= scuttlebutt# IKprDvV7- po
> > >
> > > hopefully its of interest to someone
> > >
> > > steve
> > >
> >
> >
>
--- Inbolger@yahoogroups.com, Bill Howard <billh39@...> wrote:
Fundamentally, a euphroe is a block of wood with holes in it, through which one runs line, similar to a block but without those fancy wheelie-pulley thingies. They are used in a Junk Rig to combine the various sheetlets from the various spars to a single sheet. As a Euphroe requires more pull on a line to overcome friction than a block does, in a Junk rig sheet application there will often be a mismatch of tension between the two sides of the euphroe. It's thought that by properly managing this characteristic, the sail may be made to set better.
That paragraph probably makes no sense without an accompanying diagram or twelve. Diagrams, descriptions,and more explanatory material may be found at:
The Chinese Sail
by Brian Platt
<http://www.thecheappages.com/junk/platt/platt_chinese_sail.html>
I've always found it odd that the English language terms for the various lines, spars, and apertenances associated with the Chinese Junk Rig were not taken from the Chinese terms, but were derived from Western sources. Usually English is happy to borrow (steal) and pervert foreign terms in these situations....
-Derek
>Google is picky about spelling - 'euphroe' will get you many more hits.
> Google never heard of euphros. What are they?
> On Jan 31, 2010, at 7:59 PM, eric14850 wrote:
>
Fundamentally, a euphroe is a block of wood with holes in it, through which one runs line, similar to a block but without those fancy wheelie-pulley thingies. They are used in a Junk Rig to combine the various sheetlets from the various spars to a single sheet. As a Euphroe requires more pull on a line to overcome friction than a block does, in a Junk rig sheet application there will often be a mismatch of tension between the two sides of the euphroe. It's thought that by properly managing this characteristic, the sail may be made to set better.
That paragraph probably makes no sense without an accompanying diagram or twelve. Diagrams, descriptions,and more explanatory material may be found at:
The Chinese Sail
by Brian Platt
<http://www.thecheappages.com/junk/platt/platt_chinese_sail.html>
I've always found it odd that the English language terms for the various lines, spars, and apertenances associated with the Chinese Junk Rig were not taken from the Chinese terms, but were derived from Western sources. Usually English is happy to borrow (steal) and pervert foreign terms in these situations....
-Derek
Here is a link to a LOTS of pictures of boats sporting junk rigs.http://images.google.com/images?hl=en&um=1&q=junk+rig&sa=N&start=0&ndsp=21
http://www.kastenmarine.com/junk_rig.htm
shows his take off on the junk rig A euphroe would replace the fiddle block. Because a euphroe is just a slat of wood with holes the lines pass through it has a lot of resistance. the sheet can be adjusted to pull more on one batten than another. From Kasten: "Sail shape is controlled by the sheets mainly. Each "sheetlet" runs through a "euphroe" which acts as friction block to keep the tension set as intended. In my drawing, I've made use of a simpler arrangement using a fiddle block and separate "lizard" eyes in order to allow the sail to self adjust when it is reefed."
From Wikipedia: "On a
traditional Chinese junk rig, the sail is controlled by
sheetlets -- small sheet lines running from the battens to
blocks that in turn are on lines running through a
euphroe, a long piece of wood with holes in it. This helps
maintain uniform tension in each panel of the sail." Sheetlets are the line loops from one batten down to the next.
And here is what I was looking for halfway down the page:
http://www.dragonvoyage.com/ship/rig.shtml
Western designers starting with Hastler and then Colvin followed by others have made modifications of the Junk rig. Bolger took some aspects of the junk rig and created a modern multi-yard gaff rig. Some on this forum have been (I think) referring to this as Bolger's Chinese Junk rig. It is not. The junk rig is a lug rig, and though Bolger liked the lug rig, he did not like the Chinese lug rig very much, though he respected Hastler and others who did like it. Bolger did design at least one boat that I am aware of that had the option of a Chinese Junk rig. 35'+- barge hull if I remember correctly.
Eric
http://www.kastenmarine.com/junk_rig.htm
shows his take off on the junk rig A euphroe would replace the fiddle block. Because a euphroe is just a slat of wood with holes the lines pass through it has a lot of resistance. the sheet can be adjusted to pull more on one batten than another. From Kasten: "Sail shape is controlled by the sheets mainly. Each "sheetlet" runs through a "euphroe" which acts as friction block to keep the tension set as intended. In my drawing, I've made use of a simpler arrangement using a fiddle block and separate "lizard" eyes in order to allow the sail to self adjust when it is reefed."
From Wikipedia: "On a
traditional Chinese junk rig, the sail is controlled by
sheetlets -- small sheet lines running from the battens to
blocks that in turn are on lines running through a
euphroe, a long piece of wood with holes in it. This helps
maintain uniform tension in each panel of the sail." Sheetlets are the line loops from one batten down to the next.
And here is what I was looking for halfway down the page:
http://www.dragonvoyage.com/ship/rig.shtml
Western designers starting with Hastler and then Colvin followed by others have made modifications of the Junk rig. Bolger took some aspects of the junk rig and created a modern multi-yard gaff rig. Some on this forum have been (I think) referring to this as Bolger's Chinese Junk rig. It is not. The junk rig is a lug rig, and though Bolger liked the lug rig, he did not like the Chinese lug rig very much, though he respected Hastler and others who did like it. Bolger did design at least one boat that I am aware of that had the option of a Chinese Junk rig. 35'+- barge hull if I remember correctly.
Eric
--- Inbolger@yahoogroups.com, Bill Howard <billh39@...> wrote:
>
> Google never heard of euphros. What are they?
> On Jan 31, 2010, at 7:59 PM, eric14850 wrote:
>
> > The nice thing about a small and not too serious boat is one can experiment with it without it costing too much, or anyone taking the experiment too seriously.
> >
> > Even to windward the plastic tarp is pulling quite well. :-)
> > And there are several things wrong with this set up.
> > He uses battens which are not nearly stiff enough. The wind is not blowing very hard and the battens are curved. They should be stiff enough to be straight. The mainsheet is probably not led far enough aft. The designer Tom Colvin typically uses two sheets to each junk sail with the sheets attached about a fifth of the way forward of the leech on each side of the sail to deal with this problem. It does mean using a lot of line and handling two lines to control one sail. Colvin also states emphatically to resist the urge to use blocks in place of euphros. One wants the resistance a euphro provides and a block does not in order to set the sail properly. A properly set junk sail will have each batten in a line virtually parallel to the mast, or just the slightest twist at the top where the wind is stronger. Only the bottom three battens of the blue tarp are set correctly.
> >
> > Fun to experiment with, the junk sail is best suited to situations where safety requires all sail handling to be done from the cockpit or control station (Jester), to safely/easily handle a large sail (especially reefing), or to make inadequate sailmaterial adequate to the job of motivating a boat in all sailing weather, including the ability to sail to windward.
> >
> > On a small boat with the possibility of good sail cloth, the balanced lug will set far better than this junk sail was setting, and will, in my experience (using an old mainsail (too flat a cut to be ideal) with a yard taking the place of the top third of the sail) a well set balanced lug sail is capable of pointing just as high and motivating a boat just as fast as modern fin keel high masted sloops of similar size. In 25mph gusting to 35mph winds (finally winds strong enough to fill the eight oz sailcloth!) ROGUE outsailed the few other boats of similar size, and most that were larger on the lake, and kept up with a well sailed racer/cruiser that club races twice a week and is a few feet longer than ROGUE. That boat was crewed, I sailed alone. Once tacked, ROGUE was capable of sailing itself, so, as with the other boats, I strolled up to the mainmast to enjoy the scenery including the other boat's attempts to trim sails more effectively, while Rogue sailed itself. So much for the innate superiority of the modern sloop. Furthermore, at the time ROGUE's leeboards were only partially lowered. My guess is we could easily have sailed in three feet of water. None of the other boats could have followed us into such shallow water. Raising the leeboards would have allowed me to sail in these winds in even shallower water.
> >
> > Eric
> >
> > --- Inbolger@yahoogroups.com, "steve" <stevepallen@> wrote:
> > >
> > > I came across this on a meander,
> > >
> > >http://www.keepturningleft.co.uk/keepturningleft.php?type=scuttlebutt#IKprDvV7-po
> > >
> > > hopefully its of interest to someone
> > >
> > > steve
> > >
> >
> >
>
Google never heard of euphros. What are they?
On Jan 31, 2010, at 7:59 PM, eric14850 wrote:The nice thing about a small and not too serious boat is one can experiment with it without it costing too much, or anyone taking the experiment too seriously.
Even to windward the plastic tarp is pulling quite well. :-)
And there are several things wrong with this set up.
He uses battens which are not nearly stiff enough. The wind is not blowing very hard and the battens are curved. They should be stiff enough to be straight. The mainsheet is probably not led far enough aft. The designer Tom Colvin typically uses two sheets to each junk sail with the sheets attached about a fifth of the way forward of the leech on each side of the sail to deal with this problem. It does mean using a lot of line and handling two lines to control one sail. Colvin also states emphatically to resist the urge to use blocks in place of euphros. One wants the resistance a euphro provides and a block does not in order to set the sail properly. A properly set junk sail will have each batten in a line virtually parallel to the mast, or just the slightest twist at the top where the wind is stronger. Only the bottom three battens of the blue tarp are set correctly.
Fun to experiment with, the junk sail is best suited to situations where safety requires all sail handling to be done from the cockpit or control station (Jester), to safely/easily handle a large sail (especially reefing), or to make inadequate sailmaterial adequate to the job of motivating a boat in all sailing weather, including the ability to sail to windward.
On a small boat with the possibility of good sail cloth, the balanced lug will set far better than this junk sail was setting, and will, in my experience (using an old mainsail (too flat a cut to be ideal) with a yard taking the place of the top third of the sail) a well set balanced lug sail is capable of pointing just as high and motivating a boat just as fast as modern fin keel high masted sloops of similar size. In 25mph gusting to 35mph winds (finally winds strong enough to fill the eight oz sailcloth!) ROGUE outsailed the few other boats of similar size, and most that were larger on the lake, and kept up with a well sailed racer/cruiser that club races twice a week and is a few feet longer than ROGUE. That boat was crewed, I sailed alone. Once tacked, ROGUE was capable of sailing itself, so, as with the other boats, I strolled up to the mainmast to enjoy the scenery including the other boat's attempts to trim sails more effectively, while Rogue sailed itself. So much for the innate superiority of the modern sloop. Furthermore, at the time ROGUE's leeboards were only partially lowered. My guess is we could easily have sailed in three feet of water. None of the other boats could have followed us into such shallow water. Raising the leeboards would have allowed me to sail in these winds in even shallower water.
Eric
--- Inbolger@yahoogroups. com, "steve" <stevepallen@ ...> wrote:
>
> I came across this on a meander,
>
>http://www.keepturn ingleft.co. uk/keepturningle ft.php?type= scuttlebutt# IKprDvV7- po
>
> hopefully its of interest to someone
>
> steve
>
The nice thing about a small and not too serious boat is one can experiment with it without it costing too much, or anyone taking the experiment too seriously.
Even to windward the plastic tarp is pulling quite well. :-)
And there are several things wrong with this set up.
He uses battens which are not nearly stiff enough. The wind is not blowing very hard and the battens are curved. They should be stiff enough to be straight. The mainsheet is probably not led far enough aft. The designer Tom Colvin typically uses two sheets to each junk sail with the sheets attached about a fifth of the way forward of the leech on each side of the sail to deal with this problem. It does mean using a lot of line and handling two lines to control one sail. Colvin also states emphatically to resist the urge to use blocks in place of euphros. One wants the resistance a euphro provides and a block does not in order to set the sail properly. A properly set junk sail will have each batten in a line virtually parallel to the mast, or just the slightest twist at the top where the wind is stronger. Only the bottom three battens of the blue tarp are set correctly.
Fun to experiment with, the junk sail is best suited to situations where safety requires all sail handling to be done from the cockpit or control station (Jester), to safely/easily handle a large sail (especially reefing), or to make inadequate sailmaterial adequate to the job of motivating a boat in all sailing weather, including the ability to sail to windward.
On a small boat with the possibility of good sail cloth, the balanced lug will set far better than this junk sail was setting, and will, in my experience (using an old mainsail (too flat a cut to be ideal) with a yard taking the place of the top third of the sail) a well set balanced lug sail is capable of pointing just as high and motivating a boat just as fast as modern fin keel high masted sloops of similar size. In 25mph gusting to 35mph winds (finally winds strong enough to fill the eight oz sailcloth!) ROGUE outsailed the few other boats of similar size, and most that were larger on the lake, and kept up with a well sailed racer/cruiser that club races twice a week and is a few feet longer than ROGUE. That boat was crewed, I sailed alone. Once tacked, ROGUE was capable of sailing itself, so, as with the other boats, I strolled up to the mainmast to enjoy the scenery including the other boat's attempts to trim sails more effectively, while Rogue sailed itself. So much for the innate superiority of the modern sloop. Furthermore, at the time ROGUE's leeboards were only partially lowered. My guess is we could easily have sailed in three feet of water. None of the other boats could have followed us into such shallow water. Raising the leeboards would have allowed me to sail in these winds in even shallower water.
Eric
Even to windward the plastic tarp is pulling quite well. :-)
And there are several things wrong with this set up.
He uses battens which are not nearly stiff enough. The wind is not blowing very hard and the battens are curved. They should be stiff enough to be straight. The mainsheet is probably not led far enough aft. The designer Tom Colvin typically uses two sheets to each junk sail with the sheets attached about a fifth of the way forward of the leech on each side of the sail to deal with this problem. It does mean using a lot of line and handling two lines to control one sail. Colvin also states emphatically to resist the urge to use blocks in place of euphros. One wants the resistance a euphro provides and a block does not in order to set the sail properly. A properly set junk sail will have each batten in a line virtually parallel to the mast, or just the slightest twist at the top where the wind is stronger. Only the bottom three battens of the blue tarp are set correctly.
Fun to experiment with, the junk sail is best suited to situations where safety requires all sail handling to be done from the cockpit or control station (Jester), to safely/easily handle a large sail (especially reefing), or to make inadequate sailmaterial adequate to the job of motivating a boat in all sailing weather, including the ability to sail to windward.
On a small boat with the possibility of good sail cloth, the balanced lug will set far better than this junk sail was setting, and will, in my experience (using an old mainsail (too flat a cut to be ideal) with a yard taking the place of the top third of the sail) a well set balanced lug sail is capable of pointing just as high and motivating a boat just as fast as modern fin keel high masted sloops of similar size. In 25mph gusting to 35mph winds (finally winds strong enough to fill the eight oz sailcloth!) ROGUE outsailed the few other boats of similar size, and most that were larger on the lake, and kept up with a well sailed racer/cruiser that club races twice a week and is a few feet longer than ROGUE. That boat was crewed, I sailed alone. Once tacked, ROGUE was capable of sailing itself, so, as with the other boats, I strolled up to the mainmast to enjoy the scenery including the other boat's attempts to trim sails more effectively, while Rogue sailed itself. So much for the innate superiority of the modern sloop. Furthermore, at the time ROGUE's leeboards were only partially lowered. My guess is we could easily have sailed in three feet of water. None of the other boats could have followed us into such shallow water. Raising the leeboards would have allowed me to sail in these winds in even shallower water.
Eric
--- Inbolger@yahoogroups.com, "steve" <stevepallen@...> wrote:
>
> I came across this on a meander,
>
>http://www.keepturningleft.co.uk/keepturningleft.php?type=scuttlebutt#IKprDvV7-po
>
> hopefully its of interest to someone
>
> steve
>
I came across this on a meander,
http://www.keepturningleft.co.uk/keepturningleft.php?type=scuttlebutt#IKprDvV7-po
hopefully its of interest to someone
steve
http://www.keepturningleft.co.uk/keepturningleft.php?type=scuttlebutt#IKprDvV7-po
hopefully its of interest to someone
steve