Re: Large hull panel laminating via nailing/vac bagging/screwing
Rick, Good report. I'm convinced to predrill a hole for drywall screw clamping in future.
Joe T
Joe T
--- Inbolger@yahoogroups.com, Rick Bedard <sctree@...> wrote:
>
> A few years ago I worked with (he actually paid me!) a local engineer who needed a low tech voidless plywood/epoxy lamination, for an application (non-boating) to be assembled in the jungle of Ecuador . We made over thirty samples using two layers of 1/2" very nice marine grade ply, 24" x 48" bent over a curved jig. All components (ply, epoxy, fillers even the screws) were carefully weighed on a highly accurate scale both before and after glue-up, the squeezeout was carefully collected and weighed, and the finished panels were sliced and diced into very thin sections and examined under a microscope, yes a microscope! He ended up with lots of data, spread sheets and charts that confirmed what was obvious to me by the end of our gluing session. We used a variety of screws; wood, self tapping, sheet metal, deck, flooring, drywall both coarse and fine threaded, as well as machine screws and bolts with washers and nuts, also several types of nails including
> ring shank, and several types of pneumatic nail gun driven staples and brads.
>
> As he needed a metal free product the nailed sections that we couldn't easily extract the fasteners from were useless to him, but still examined and rated for voids against all the others. The bolted up section using 1/4 x 20 bolts and nuts was a failure as the pressure, even with pads, was very uneven distributed and actually caused big voids between the bolt locations.
>
> Bottom line best "low tech" evenly distributed clamping pressure, high squeeze out and no detectable voids, by a wide margin came from using a battery drill driver on fine threaded 2" long drywall screws through 1/4" x 2" x 2" ply pads with a square of 20 mil poly (for a barrier to keep the pads from sticking like Joe said), with over sized holes in both the pad and the top ply layer, plus most important - the screws were run clean through the bottom layer, all on a six inch grid. Down side for a boat builder would be all the holes through the lamination, which didn't bother him as he intended to fill the holes with epoxy and dowels and then add a layer of glass to both sides.
>
>
>
> Man I coulda built a nice boat from the plywood he consumed.....
>
> Rick
>
>
>
>
> --- On Sun, 12/13/09, Joe <scsbmsjoe@...> wrote:
>
> From: Joe <scsbmsjoe@...>
> Subject: [bolger] Re: Large hull panel laminating via nailing/vac bagging/screwing
> To:bolger@yahoogroups.com
> Date: Sunday, December 13, 2009, 9:24 PM
>
> I don't think it is necessary to pre-drill holes for drywall screws. Just apply enough pressure to keep the panel in contact. I generally use small 1&1/2 inch square ply pads with screws to help distribute the pressure. That way there is no squeeze through from below. If that is a concern then use a plastic barrier.
>
> Joe T
>
> > I think I prefer the idea of drilling small holes through the first
> > layer ...Nels
>
>
>
> ------------------------------------
>
> 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
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>
I would not recommend using Luann. The Luann boat I made died in a year from delamination. It was the worst $126 I saved in my whole life. The materials you use for the hull are the cheapest things you put into the boat. Most smaller stitch and glue or nail and glue sailboat designs use 4-12 sheets of plywood and 2-3 gallons of epoxy. The epoxy costs $120 to $300 depending whether you need two or three gallons and brand you choose. The difference in cost for 8 sheets of plywood between $22 Luann ($176) and $85 Okoume ($680) is $504. For a two sheet Bolger Nymph the difference is $126. Against that consider that it seems to take most people (including me) about a year of nights and weekends and a couple of hundred hours to launch a light schooner and about three months to launch a Bolger Nymph. At a rate of $10 hour, your labor going into the Light Schooner is worth $2,000-$3,000 and the Nymph is about $400-$500. If you buy Luann you will save about $500 in a Light Schooner. But your boat will die in a much shorter time period. Even really good Luann will die much faster than Okoume. If you really cannot afford Okoume or another high quality rot resistant plywood, buy fir. It will check but last, and it will not delaminate instantly. Consider the value of your time. Why spend a year making a boat that will only last a year or two? --- OnSat, 12/12/09,gary<gbship@...>wrote:
|
I seem to keep messing this up, so if it happens again I am sorry. And thank you. I am looking for info on Black Gauntlet 2. Any and all info is welcome and appreciated.
I have sent two letters to Susanne Altenburger C/O PB&F, asking for info/plans on this and several other designs. Only to get them back stamped Deceased by the USPS. I am going going to build my last two boats this year and would like them to be "Bolger Boats".
I have sent two letters to Susanne Altenburger C/O PB&F, asking for info/plans on this and several other designs. Only to get them back stamped Deceased by the USPS. I am going going to build my last two boats this year and would like them to be "Bolger Boats".
I seem to keep messing this up, so if it happens again I am sorry. And thank you. I am looking for info on Black Gauntlet 2. Any and all info is welcome and appreciated.
I have sent two letters to Susanne Altenburger C/O PB&F, asking for info/plans on this and several other designs. Only to get them back stamped Deceased by the USPS. I am going going to build my last two boats this year and would like them to be "Bolger Boats".
Christopher C. Wetherill wrote:
I have sent two letters to Susanne Altenburger C/O PB&F, asking for info/plans on this and several other designs. Only to get them back stamped Deceased by the USPS. I am going going to build my last two boats this year and would like them to be "Bolger Boats".
Christopher C. Wetherill wrote:
>
> From long experience with short drywall screws, the
> full length threads cause the head to stop before any clamping force is
> developed. Four possible events present if the screws are tightened
> past the point where the head stops 1) the wood strips on the top layer
> and allows tightening. 2) the wood strips in both layers. 3) the head
> crushes the top layer 4) the head snaps off. Only one of these
> outcomes is desirable. I would guess about 5 to 10% probability of
> failure on any given screw and near 0 failure if clearance holes are
> pre-drilled in the top layer.
> The clamping blocks are definitely a good idea. I haven't tried it
> myself, but I have read that they can be coated with paraffin to
> prevent sticking
> V/R
> Chris
> Joe wrote:
> I don't think it is necessary to pre-drill holes for drywall screws. Just apply enough pressure to keep the panel in contact. I generally use small 1&1/2 inch square ply pads with screws to help distribute the pressure. That way there is no squeeze through from below. If that is a concern then use a plastic barrier.
> Joe T
> I think I prefer the idea of drilling small holes through the first
> layer ...Nels
> ------------ --------- --------- ------
> 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. com Yahoo! Groups Links
> Individual Email | Traditional
> http://docs. yahoo.com/ info/terms/
>
| A few years ago I worked with (he actually paid me!) a local engineer who needed a low tech voidless plywood/epoxy lamination, for an application (non-boating) to be assembled in the jungle of Ecuador . We made over thirty samples using two layers of 1/2" very nice marine grade ply, 24" x 48" bent over a curved jig. All components (ply, epoxy, fillers even the screws) were carefully weighed on a highly accurate scale both before and after glue-up, the squeezeout was carefully collected and weighed, and the finished panels were sliced and diced into very thin sections and examined under a microscope, yes a microscope! He ended up with lots of data, spread sheets and charts that confirmed what was obvious to me by the end of our gluing session. We used a variety of screws; wood, self tapping, sheet metal, deck, flooring, drywall both coarse and fine threaded, as
well as machine screws and bolts with washers and nuts, also several types of nails including ring shank, and several types of pneumatic nail gun driven staples and brads. As he needed a metal free product the nailed sections that we couldn't easily extract the fasteners from were useless to him, but still examined and rated for voids against all the others. The bolted up section using 1/4 x 20 bolts and nuts was a failure as the pressure, even with pads, was very uneven distributed and actually caused big voids between the bolt locations. Bottom line best "low tech" evenly distributed clamping pressure, high squeeze out and no detectable voids, by a wide margin came from using a battery drill driver on fine threaded 2" long drywall screws through 1/4" x 2" x 2" ply pads with a square of 20 mil poly (for a barrier to keep the pads from sticking like Joe said), withover sizedholes in both the padandthe top ply layer,plus most important - the screws were run clean through the bottom layer,all on a six inch grid. Down side for a boat builder would be all the holes through the lamination, which didn't bother him as he intended to fill the holes with epoxy and dowels and then add a layer of glass to both sides. Man I coulda built a nice boat from the plywood he consumed..... Rick --- OnSun, 12/13/09, Joe<scsbmsjoe@...>wrote: |
From long experience with short drywall screws, the
full length threads cause the head to stop before any clamping force is
developed. Four possible events present if the screws are tightened
past the point where the head stops 1) the wood strips on the top layer
and allows tightening. 2) the wood strips in both layers. 3) the head
crushes the top layer 4) the head snaps off. Only one of these
outcomes is desirable. I would guess about 5 to 10% probability of
failure on any given screw and near 0 failure if clearance holes are
pre-drilled in the top layer.
The clamping blocks are definitely a good idea. I haven't tried it myself, but I have read that they can be coated with paraffin to prevent sticking
V/R
Chris
Joe wrote:
The clamping blocks are definitely a good idea. I haven't tried it myself, but I have read that they can be coated with paraffin to prevent sticking
V/R
Chris
Joe wrote:
I don't think it is necessary to pre-drill holes for drywall screws. Just apply enough pressure to keep the panel in contact. I generally use small 1&1/2 inch square ply pads with screws to help distribute the pressure. That way there is no squeeze through from below. If that is a concern then use a plastic barrier. Joe TI think I prefer the idea of drilling small holes through the first layer ...Nels------------------------------------ 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 don't think it is necessary to pre-drill holes for drywall screws. Just apply enough pressure to keep the panel in contact. I generally use small 1&1/2 inch square ply pads with screws to help distribute the pressure. That way there is no squeeze through from below. If that is a concern then use a plastic barrier.
Joe T
Joe T
> I think I prefer the idea of drilling small holes through the first
> layer ...Nels
Stuck drywall screws can be removed by heating the heads with a
soldering iron.
I think I prefer the idea of drilling small holes through the first
layer and using ring nails.
Nels
soldering iron.
I think I prefer the idea of drilling small holes through the first
layer and using ring nails.
Nels
--- Inbolger@yahoogroups.com, Bruce Hallman <hallman@...> wrote:
>
> >drywall screw-guns
>
> I ditto Susanne with her description of the very handy option of using
> drywall screws.
I found I like useing the zink plated sheet metal screws that have what looks like a washer all ready stamped into the head. When putting down 3/8" coldmolding I used a 6" pattern and like said worked from the edge across to get all the air out.
Jon
Jon
Bruce,
Wow, what a surprise when I looked at the photos. I had sides when I was applying my bottom. Whood a thunk it could be done that way!
Sincerely,
Gene T.
On 13 Dec, 2009, at 1:55 PM, Bruce Hallman wrote:
>drywall screw-guns
I ditto Susanne with her description of the very handy option of using
drywall screws. I have used thousands, and they make an excellent and
cheap method of fastening things together while the glue sets. A big
caveat she makes, which I also ditto, is that if you want to remove
the screw, it must be done before the glue sets fully. Otherwise, the
screws often snap off at the head leaving the steel screw shaft inside
the wood.
That is why my personal favorite is the use of ring shank silicon
bronze nails. They hold as tight as screws, cost the same or cheaper,
are as easy or easier to install and they are soft enough that they
can be worked with power tools. In the case of layers of plywood,
silicon bronze yields to the belt sander, which makes preparation of
the surface for the Payson joint, and the field cloth, to be easy
work.
I happened to save a few photos of this process in action on the Topaz bottom...
http://hallman. org/webcam/ I/hour53. html
On Sat, Dec 12, 2009 at 7:27 PM, Rick Bedard <sctree@...> wrote:
the Topaz Spider is effectively done enough to call it done.
Remaining work includes closing up the fuel tank boxes, paint of the
interior of the motorwell, finishing the running lights, dashboard
gauges (if any), finish caulking of the windshield. And, launch.
Some pretty recent photos here...
http://www.flickr.com/photos/hallman/tags/topazspyder/
The truth be told, I have been focusing my attention these last few
months on a house remodel job in San Francisco, and less on the boat.
The rear wall cut out of the garage is sized to be replaced with a
nine foot wide rolling garage door, so I can have 'drive through'
capability in the garage with front and back rolling doors.
I haven't really been thinking much of the 'next boat', though I would
like to build a pair of 'his and her' Diamonds.
And also some heresy, I have been planning out the design and
construction of a series of bamboo-hemp-aluminum bicycles. The
struts made of bamboo, shear-reinforced with epoxy impregnated hemp
wrapping at the strut ends, and the truss joints made of cast recycled
aluminum, using sand casting/foundry in the style of Dave Gingery.
> "The Topaz Spyder I built"You know how it it, does 99% done equal done? In practical purposes,
>
> Hey Bruce, does that mean she's done?
>
> If so, congrats.... and where are the pics?
> If not I won't pester you with the "when is launching day" question, as we all know how hard that can be to nail down, but I will ask what's the next next build? Still looking to build Yonder? Or what? And are you going to have to replace that rear wall in your boatshop?
>
> Rick Bedard
the Topaz Spider is effectively done enough to call it done.
Remaining work includes closing up the fuel tank boxes, paint of the
interior of the motorwell, finishing the running lights, dashboard
gauges (if any), finish caulking of the windshield. And, launch.
Some pretty recent photos here...
http://www.flickr.com/photos/hallman/tags/topazspyder/
The truth be told, I have been focusing my attention these last few
months on a house remodel job in San Francisco, and less on the boat.
The rear wall cut out of the garage is sized to be replaced with a
nine foot wide rolling garage door, so I can have 'drive through'
capability in the garage with front and back rolling doors.
I haven't really been thinking much of the 'next boat', though I would
like to build a pair of 'his and her' Diamonds.
And also some heresy, I have been planning out the design and
construction of a series of bamboo-hemp-aluminum bicycles. The
struts made of bamboo, shear-reinforced with epoxy impregnated hemp
wrapping at the strut ends, and the truss joints made of cast recycled
aluminum, using sand casting/foundry in the style of Dave Gingery.
>drywall screw-gunsI ditto Susanne with her description of the very handy option of using
drywall screws. I have used thousands, and they make an excellent and
cheap method of fastening things together while the glue sets. A big
caveat she makes, which I also ditto, is that if you want to remove
the screw, it must be done before the glue sets fully. Otherwise, the
screws often snap off at the head leaving the steel screw shaft inside
the wood.
That is why my personal favorite is the use of ring shank silicon
bronze nails. They hold as tight as screws, cost the same or cheaper,
are as easy or easier to install and they are soft enough that they
can be worked with power tools. In the case of layers of plywood,
silicon bronze yields to the belt sander, which makes preparation of
the surface for the Payson joint, and the field cloth, to be easy
work.
I happened to save a few photos of this process in action on the Topaz bottom...
http://hallman.org/webcam/I/hour53.html
Patrick
Mark Albanese wrote:
I just saw some pretty good looking 5.2mm Luan at Lowes here @ Delta Park, Portland Oregon. The tag claims Type 1 exterior glue - that's that waterproof stuff, not just moisture resistant as seen previously. Mark On Dec 12, 2009, at 5:13 AM, Bill Howard wrote:My personal experience with 5mm luan reminded me of Dynamite Payson's comment in one of his Instant Boat books, that he would as soon build a boat with shredded wheat. The luan available here tends to delaminate on the way home from Lowes.
This is pretty much how I put the bottom on the Work Skiff. I laid out a 12X12 grid, drilled one layer to the shank of the nail, and then used bronze nails to bang it together. I find nailing faster than screws, and with bronze, I left them in place.
The rails of the skiff were put on with stainless screws placed in oversized holes to draw the pieces of wood together as the glue set.
David Jost
"bemoaning the low temps precluding any of this today."
The rails of the skiff were put on with stainless screws placed in oversized holes to draw the pieces of wood together as the glue set.
David Jost
"bemoaning the low temps precluding any of this today."
--- Inbolger@yahoogroups.com, "Susanne@..." <philbolger@...> wrote:
>
> Question !
> On projects with multiple layers of ply there is one more option, in addition to vacuum-bagging and nailing:
> - Particularly for largish full-length hull-panels we have also proposed using short drywall screws to temporarily produce local pressure until epoxy sets up with immediate removal the next day while the screws still can be pulled.
>
> This may have been discussed here over the years but I'd like some feedback to contextualize this option next to the other two already raised by a number of folks so far.
>
> Proposed process:
> 1.) Wet out both panels' facing sides.
>
> 2.) Start at the 'first' butt-joint along the centerline of each panel, using a 9x9 to 12x12-inch pattern to shoot the screws as we move across the panel and outwards from the centerline.
>
> 3.) Pulling them next day is important as the epoxy will still release them without much drama; your timing will vary with conditions and epoxy...
>
> Assumptions:
> 1.) After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
> - that established shape allows screw-tacking in place
> - and router-cutting the second+ layer(s) dry,
> - then 'untacking',
> - epoxying each face,
> - followed by screw-gun mania.
>
> 2.) Testing with scraps of chosen plywood and chosen screws will determine clutch-setting (if any) before snapping off these ferrous screws with potential 'drama' later in hull-life should the panel still get moist somehow.
>
> 3.) With disciplined removal schedule, pressure for joining of any size panels can be brought to bear just about anywhere on the emerging structure - top-down, upwards, sideways etc - or just across saw-hourse/jigs/backbones with gravity as your friend.
>
> 4.) Pressure seems less relevant since epoxybonds like to be reasonably aligned but do not need to be wood-glue correctly squeezed to perform.
>
> 5.) There is a pay-off of time versus relative epoxy-use between panels - assuming voidless epoxy-application via serrated trowel - of screwing panels ("get over it...") versus setting up vacuum-bagging procedure.
>
> 6.) In both cases the 'next' layer has to wait until that first bond is cured - unless you dare to challenge the odds of moisture inside the panel and ferrous screws 'encapsulated' for good... I'd likely rather use faster-setting epoxy or line up enough work for the day so that no time is wasted 'watching epoxy cure'...
>
> 7.) Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per boat-buolding session.
>
> 8.) The zillion holes can be tended to by rapid syringe&smear or dab&smear filling mania or might even 'get lost' in the glassing process anyway. 'Hole Phobia' stems from conventional pre-epoxy reflexes and matching-grain opportunities typically irrelevant once you are in full plywood/epoxy mode.
>
> Faster yet/multi-person procress:
> 1.) Once in the 'groove', with lengthy panels ahead, one of these self-feeding (like machine-gun ammo) drywall screw-guns might pay for itself, particularly the long-handled ones for upright shooting&walking the length of the panel...
>
> 2.) With 2 folks moving 1/2" panels and cutting them to shape, a third person can man the gear-pump to produce epoxy fast enough to get a several panels done per hour. Again, the usual procedure:
> - After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
> - that established shape allows screw-tacking in place
> - and router-cutting the second+ layer(s) dry,
> - then 'untacking' them,
> - epoxying each face,
> - followed by screw-gun mania.
> Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per day and week particularly on medium and larger hulls.
>
> This should allow quite cost-effective progress in a commercial setting, butt-laminating large mono-coque hulls rapidly with a modest crew.
>
> Phil liked the importance of these lowly screws as modest but epoxy-effective 'any-place clamps' in bona fide boat-building.
>
> Question ?:
> What do we overlook with this approach ? Liabilities ?
>
> Susanne Altenburger, PB&F
>
Susanne,
Screws must be chosen wisely so that threads are not engaged in the outer layer preventing the panels from being drawn together. I know that is the correct way to do things but in the home environment one typically doesn't have a good selection of screws. Here again is a case where predrilling the outer layer large enough to clear the threads could make it work better. And, adjusting the clutch would be critical with thinner plys, like the 1/4 inch I used on my Micro Navigator bottom.
Sincerely,
Gene Tehansky
On 13 Dec, 2009, at 8:39 AM,Susanne@...wrote:
Question !
On projects with multiple layers of ply there is one more option, in addition to vacuum-bagging and nailing:
- Particularly for largish full-length hull-panels we have also proposed using short drywall screws to temporarily produce local pressure until epoxy sets up with immediate removal the next day while the screws still can be pulled.
This may have been discussed here over the years but I'd like some feedback to contextualize this option next to the other two already raised by a number of folks so far.
Proposed process:
1.) Wet out both panels' facing sides.
2.) Start at the 'first' butt-joint along the centerline of each panel, using a 9x9 to 12x12-inch pattern to shoot the screws as we move across the panel and outwards from the centerline.
3.) Pulling them next day is important as the epoxy will still release them without much drama; your timing will vary with conditions and epoxy...
Assumptions:
1.) After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s) dry,
- then 'untacking',
- epoxying each face,
- followed by screw-gun mania.
2.) Testing with scraps of chosen plywood and chosen screws will determine clutch-setting (if any) before snapping off these ferrous screws with potential 'drama' later in hull-life should the panel still get moist somehow.
3.) With disciplined removal schedule, pressure for joining of any size panels can be brought to bear just about anywhere on the emerging structure - top-down, upwards, sideways etc - or just across saw-hourse/jigs/ backbones with gravity as your friend.
4.) Pressure seems less relevant since epoxybonds like to be reasonably aligned but do not need to be wood-glue correctly squeezed to perform.
5.) There is a pay-off of time versus relative epoxy-use between panels - assuming voidless epoxy-application via serrated trowel - of screwing panels ("get over it...") versus setting up vacuum-bagging procedure.
6.) In both cases the 'next' layer has to wait until that first bond is cured - unless you dare to challenge the odds of moisture inside the panel and ferrous screws 'encapsulated' for good... I'd likely rather use faster-setting epoxy or line up enough work for the day so that no time is wasted 'watching epoxy cure'...
7.) Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per boat-buolding session.
8.) The zillion holes can be tended to by rapid syringe&smear or dab&smear filling mania or might even 'get lost' in the glassing process anyway. 'Hole Phobia' stems from conventional pre-epoxy reflexes and matching-grain opportunities typically irrelevant once you are in full plywood/epoxy mode.
Faster yet/multi-person procress:
1.) Once in the 'groove', with lengthy panels ahead, one of these self-feeding (like machine-gun ammo) drywall screw-guns might pay for itself, particularly the long-handled ones for upright shooting&walking the length of the panel...
2.) With 2 folks moving 1/2" panels and cutting them to shape, a third person can man the gear-pump to produce epoxy fast enough to get a several panels done per hour. Again, the usual procedure:
- After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s) dry,
- then 'untacking' them,
- epoxying each face,
- followed by screw-gun mania.
Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per day and week particularly on medium and larger hulls.This should allow quite cost-effective progress in a commercial setting, butt-laminating large mono-coque hulls rapidly with a modest crew.
Phil liked the importance of these lowly screws as modest but epoxy-effective 'any-place clamps' in bona fide boat-building.
Question ?:
What do we overlook with this approach ? Liabilities ?
Susanne Altenburger, PB&F
Question!
On projects with multiple layers of ply there is one more option, in addition to vacuum-bagging and nailing:
- Particularly for largish full-length hull-panels we have also proposed using short drywall screws to temporarily produce local pressure until epoxy sets up with immediate removal the next day while the screws still can be pulled.
This may have been discussed here over the years but I'd like some feedback to contextualize this option next to the other two already raised by a number of folks so far.
Proposed process:
1.) Wet out both panels' facing sides.
2.) Start at the 'first' butt-joint along the centerline of each panel, using a 9x9 to 12x12-inch pattern to shoot the screws as we move across the panel and outwards from the centerline.
3.) Pulling them next day is important as the epoxy will still release them without much drama; your timing will vary with conditions and epoxy...
Assumptions:
1.) After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s)dry,
- then 'untacking',
- epoxying each face,
- followed by screw-gun mania.
2.) Testing with scraps of chosen plywood and chosen screws will determine clutch-setting (if any) before snapping off these ferrous screws with potential 'drama' later in hull-life should the panel still get moist somehow.
3.) With disciplined removal schedule, pressure for joining of any size panels can be brought to bear just about anywhere on the emerging structure - top-down, upwards, sideways etc - or just across saw-hourse/jigs/backbones with gravity as your friend.
4.) Pressure seems less relevant since epoxybonds like to be reasonably aligned but do not need to be wood-glue correctly squeezed to perform.
5.) There is a pay-off of time versus relative epoxy-use between panels - assuming voidless epoxy-application via serrated trowel - of screwing panels ("get over it...") versus setting up vacuum-bagging procedure.
6.) In both cases the 'next' layer has to wait until that first bond is cured - unless you dare to challenge the odds of moisture inside the panel and ferrous screws 'encapsulated' for good... I'd likely rather use faster-setting epoxy or line up enough work for the day so that no time is wasted 'watching epoxy cure'...
7.) Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per boat-buolding session.
8.) The zillion holes can be tended to by rapid syringe&smear or dab&smear filling mania or might even 'get lost' in the glassing process anyway. 'Hole Phobia' stems from conventional pre-epoxy reflexes and matching-grain opportunities typically irrelevant once you are in full plywood/epoxy mode.
Faster yet/multi-person procress:
1.) Once in the 'groove', with lengthy panels ahead, one of these self-feeding (like machine-gun ammo) drywall screw-guns might pay for itself, particularly the long-handled ones for upright shooting&walking the length of the panel...
2.) With 2 folks moving 1/2" panels and cutting them to shape, a third person can man the gear-pump to produce epoxy fast enough to get a several panels done per hour. Again, the usual procedure:
- After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s) dry,
- then 'untacking' them,
- epoxying each face,
- followed by screw-gun mania.
Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per day and week particularly on medium and larger hulls.
On projects with multiple layers of ply there is one more option, in addition to vacuum-bagging and nailing:
- Particularly for largish full-length hull-panels we have also proposed using short drywall screws to temporarily produce local pressure until epoxy sets up with immediate removal the next day while the screws still can be pulled.
This may have been discussed here over the years but I'd like some feedback to contextualize this option next to the other two already raised by a number of folks so far.
Proposed process:
1.) Wet out both panels' facing sides.
2.) Start at the 'first' butt-joint along the centerline of each panel, using a 9x9 to 12x12-inch pattern to shoot the screws as we move across the panel and outwards from the centerline.
3.) Pulling them next day is important as the epoxy will still release them without much drama; your timing will vary with conditions and epoxy...
Assumptions:
1.) After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s)dry,
- then 'untacking',
- epoxying each face,
- followed by screw-gun mania.
2.) Testing with scraps of chosen plywood and chosen screws will determine clutch-setting (if any) before snapping off these ferrous screws with potential 'drama' later in hull-life should the panel still get moist somehow.
3.) With disciplined removal schedule, pressure for joining of any size panels can be brought to bear just about anywhere on the emerging structure - top-down, upwards, sideways etc - or just across saw-hourse/jigs/backbones with gravity as your friend.
4.) Pressure seems less relevant since epoxybonds like to be reasonably aligned but do not need to be wood-glue correctly squeezed to perform.
5.) There is a pay-off of time versus relative epoxy-use between panels - assuming voidless epoxy-application via serrated trowel - of screwing panels ("get over it...") versus setting up vacuum-bagging procedure.
6.) In both cases the 'next' layer has to wait until that first bond is cured - unless you dare to challenge the odds of moisture inside the panel and ferrous screws 'encapsulated' for good... I'd likely rather use faster-setting epoxy or line up enough work for the day so that no time is wasted 'watching epoxy cure'...
7.) Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per boat-buolding session.
8.) The zillion holes can be tended to by rapid syringe&smear or dab&smear filling mania or might even 'get lost' in the glassing process anyway. 'Hole Phobia' stems from conventional pre-epoxy reflexes and matching-grain opportunities typically irrelevant once you are in full plywood/epoxy mode.
Faster yet/multi-person procress:
1.) Once in the 'groove', with lengthy panels ahead, one of these self-feeding (like machine-gun ammo) drywall screw-guns might pay for itself, particularly the long-handled ones for upright shooting&walking the length of the panel...
2.) With 2 folks moving 1/2" panels and cutting them to shape, a third person can man the gear-pump to produce epoxy fast enough to get a several panels done per hour. Again, the usual procedure:
- After the first 'defining' panel has been carefully set up over the backbone via 'outside' Payson-joints,
- that established shape allows screw-tacking in place
- and router-cutting the second+ layer(s) dry,
- then 'untacking' them,
- epoxying each face,
- followed by screw-gun mania.
Once jib/backbone is true and straight, and the first(starting) layer's shape is established, you could picture quite a bit of progress per day and week particularly on medium and larger hulls.
This should allow quite cost-effective progress in
a commercial setting, butt-laminating large mono-coque hulls rapidly with a
modest crew.
Phil liked the importance of these lowly screws as modest but epoxy-effective 'any-place clamps' in bona fide boat-building.
Question ?:
What do we overlook with this approach ? Liabilities ?
Susanne Altenburger, PB&F
Phil liked the importance of these lowly screws as modest but epoxy-effective 'any-place clamps' in bona fide boat-building.
Question ?:
What do we overlook with this approach ? Liabilities ?
Susanne Altenburger, PB&F
Every reputable plywood mill will produce seconds. It maybe that: the specs are a given, the sheet doesn't pass, mostly by just a hair; the sheet is not spec'd for anything else; so it's a second. It may be that it was selected for quality control, batch testing; had a small piece cut from the corner for the boil test etc. I've now a working stack of these seconds. These aren't stamped or labelled, buyer beware, they're factory seconds.
Every plywood mill will have large distributors and wholesale clients as significant customers. The mill will even purposely manufacture "seconds" for them. These indeed are factory seconds: they don't make the cut as meeting marine wood standards, as we here are concerned with. But by less even than a hair - usually amounting to cosmetics only in the exterior veneer - remember they're produced to order. The mill affixes it's label certifying these as seconds (yet still without warranty) and at retail level they sell at perhaps 10% to 20% lower in price then the standard. That might be $15 to $30 less per sheet. A significant saving off ~$150 for 7mm hoop marine. BUT get these ones from the mill and they sell at a lot less again: 50% to 75% discount, or about the same as those without the "seconds" sticker (remembering that if you can go through the mill's stack of ordinary seconds some of them are "firsts" but with a small corner piece missing.) The mill near here does a humungous trade in seconds to all standards, including marine seconds and "seconds". It's in the multi-$Ms wholesale and huge direct mill seconds retail. It's an awsomely huge business (think: several semi- or MC tankers of resorcinol per day) and staggeringly complex - but if yer can get to a mill outlet, or have someone do it for you, there's big savings and that's including freight. You'd probably have to do it yourself anywhere in the world, or cooperatively with similar minded people, as the home boat builder market is likely too fickle or thin or demanding to support a business acting like a fair buyers' agent for seconds.
Graeme
Every plywood mill will have large distributors and wholesale clients as significant customers. The mill will even purposely manufacture "seconds" for them. These indeed are factory seconds: they don't make the cut as meeting marine wood standards, as we here are concerned with. But by less even than a hair - usually amounting to cosmetics only in the exterior veneer - remember they're produced to order. The mill affixes it's label certifying these as seconds (yet still without warranty) and at retail level they sell at perhaps 10% to 20% lower in price then the standard. That might be $15 to $30 less per sheet. A significant saving off ~$150 for 7mm hoop marine. BUT get these ones from the mill and they sell at a lot less again: 50% to 75% discount, or about the same as those without the "seconds" sticker (remembering that if you can go through the mill's stack of ordinary seconds some of them are "firsts" but with a small corner piece missing.) The mill near here does a humungous trade in seconds to all standards, including marine seconds and "seconds". It's in the multi-$Ms wholesale and huge direct mill seconds retail. It's an awsomely huge business (think: several semi- or MC tankers of resorcinol per day) and staggeringly complex - but if yer can get to a mill outlet, or have someone do it for you, there's big savings and that's including freight. You'd probably have to do it yourself anywhere in the world, or cooperatively with similar minded people, as the home boat builder market is likely too fickle or thin or demanding to support a business acting like a fair buyers' agent for seconds.
Graeme
--- Inbolger@yahoogroups.com, Douglas Pollard <dougpol1@...> wrote:
>
> My Elver, not a Bolger boat, a beutiful boat though it is has big box
> plywood on the bottom and deck. I spent enough in extra glass and
> plywood trying to protect cheap plywood that I may well have been
> dollars ahead to use marine. Now I worry that such a handsome boat
> won't last. I would say unless you just can't afford marine ply buy
> it. Of course this is where somebody jumps in and says how their boat
> is really old and its made of door panel's . Doug
>
>
> Bill Howard wrote:
> >
> >
> > My personal experience with 5mm luan reminded me of Dynamite Payson's
> > comment in one of his Instant Boat books, that he would as soon build
> > a boat with shredded wheat.
> >
> >
> > The luan available here tends to delaminate on the way home from Lowes.
> >
> > If you can't find good 1/4 inch ACX plywood, consider opening your
> > piggy bank and buying 6 mm marine plywood. Yes, I know it costs about
> > eight times as much as luan.
The quality seems to vary. I bought some a few years ago, and the scraps were stored in a leaky shed. It went through several wet/dry cycles over a couple years and never delaminated. Some of the stuff recently doesn't seem near that quality. One of the local big box stores was selling water-resistant luan and a couple weeks later they were selling interior luan out of the same bin. Could have been a problem if someone wasn't looking closely. Best bet is to get a scrap or buy a sheet and test it before buying all the wood for a boat . . .
Gary
Gary
--- Inbolger@yahoogroups.com, "prairiedog2332" <arvent@...> wrote:
>
> I tested some that I found and it showed what seemed like some glue
> starvation between plies. I could peel outer plies off with a fingernail
> after several dishwasher cycles. Not enough glue maybe?
>
> So suggest you test it as well. Maybe it would work with epoxy
> encapsulation, but made me skeptical.
>
> Sure looked nice though!
>
> Nels
>
> --- Inbolger@yahoogroups.com, Mark Albanese <marka97203@> wrote:
> >
> > I just saw some pretty good looking 5.2mm Luan at Lowes here @ Delta
> > Park, Portland Oregon. The tag claims Type 1 exterior glue - that's
> > that waterproof stuff, not just moisture resistant as seen previously.
> >
> > Mark
> >
> >
> > On Dec 12, 2009, at 5:13 AM, Bill Howard wrote:
> >
> > > My personal experience with 5mm luan reminded me of Dynamite
> > > Payson's comment in one of his Instant Boat books, that he would as
> > > soon build a boat with shredded wheat.
> > >
> > > The luan available here tends to delaminate on the way home from
> > > Lowes.
> > >
> > >>
> >
>
--- OnSat, 12/12/09, Bruce Hallman<hallman@...>wrote: |
OnSat, 12/12/09, Bruce Hallman<hallman@...>wrote:
<"Using an 10 inch drywall taping knife, I mixed enough epoxy"
And just how did you manage to mix epoxy with a 10" drywall taping knife? Only kidding :) I know what you meant....
<" Hammer nailing on floppy wood can be a challenge"
Drilling tight fit pilot holes 3/4 of the way through the top layer of ply before any epoxy mixing makes for easier pounding plus you can space out the nailing grid pattern without any rush. I have even tapped the nails into the pilotholes on pieces that were easy enough to handle with all those nails pre-started, makes for a fast nail-up.
Rick
I tested some that I found and it showed what seemed like some glue
starvation between plies. I could peel outer plies off with a fingernail
after several dishwasher cycles. Not enough glue maybe?
So suggest you test it as well. Maybe it would work with epoxy
encapsulation, but made me skeptical.
Sure looked nice though!
Nels
starvation between plies. I could peel outer plies off with a fingernail
after several dishwasher cycles. Not enough glue maybe?
So suggest you test it as well. Maybe it would work with epoxy
encapsulation, but made me skeptical.
Sure looked nice though!
Nels
--- Inbolger@yahoogroups.com, Mark Albanese <marka97203@...> wrote:
>
> I just saw some pretty good looking 5.2mm Luan at Lowes here @ Delta
> Park, Portland Oregon. The tag claims Type 1 exterior glue - that's
> that waterproof stuff, not just moisture resistant as seen previously.
>
> Mark
>
>
> On Dec 12, 2009, at 5:13 AM, Bill Howard wrote:
>
> > My personal experience with 5mm luan reminded me of Dynamite
> > Payson's comment in one of his Instant Boat books, that he would as
> > soon build a boat with shredded wheat.
> >
> > The luan available here tends to delaminate on the way home from
> > Lowes.
> >
> >>
>
I just saw some pretty good looking 5.2mm Luan at Lowes here @ Delta
Park, Portland Oregon. The tag claims Type 1 exterior glue - that's
that waterproof stuff, not just moisture resistant as seen previously.
Mark
Park, Portland Oregon. The tag claims Type 1 exterior glue - that's
that waterproof stuff, not just moisture resistant as seen previously.
Mark
On Dec 12, 2009, at 5:13 AM, Bill Howard wrote:
> My personal experience with 5mm luan reminded me of Dynamite
> Payson's comment in one of his Instant Boat books, that he would as
> soon build a boat with shredded wheat.
>
> The luan available here tends to delaminate on the way home from
> Lowes.
>
>>
Speaking of Shop Vacs I had a Doctor at my shop who is a Respiratory
Specialist and he told me in no uncertain terms to vent the thing outside
with another hose before I caused my death. News to me--his expamples of why
were rather appalling.
Specialist and he told me in no uncertain terms to vent the thing outside
with another hose before I caused my death. News to me--his expamples of why
were rather appalling.
----- Original Message -----
From: "Harry James" <welshman@...>
To: <bolger@yahoogroups.com>
Sent: Saturday, December 12, 2009 3:11 PM
Subject: Re: [bolger] Re: as 29/39 scantlings
> Anywhere in the system to allow continuous airflow through the shopvac.
>
> HJ
>
> Patrick Crockett wrote:
>> A leak in the hose right before the vacuum or at the other end letting
>> air into the bag?
>>
>> Patrick
>>
>> Harry James wrote:
>>
>>> They need air flow for cooling, make sure there is an air leak to insure
>>> cooling.
>>>
>>> HJ
>>>
>>>
>>
>>
>>
>> ------------------------------------
>>
>> 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
>>
>>
>>
>>
>>
>
>
> ------------------------------------
>
> 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
>
>
>
Anywhere in the system to allow continuous airflow through the shopvac.
HJ
Patrick Crockett wrote:
HJ
Patrick Crockett wrote:
> A leak in the hose right before the vacuum or at the other end letting
> air into the bag?
>
> Patrick
>
> Harry James wrote:
>
>> They need air flow for cooling, make sure there is an air leak to insure
>> cooling.
>>
>> HJ
>>
>>
>
>
>
> ------------------------------------
>
> 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
>
>
>
>
>
Right where the hose goes into the shop vac.
On Sat, Dec 12, 2009 at 2:54 PM, Patrick Crockett<pcrockett@...>wrote:A leak in the hose right before the vacuum or at the other end letting
air into the bag?
Patrick
Harry James wrote:
> They need air flow for cooling, make sure there is an air leak to insure
> cooling.
>
> HJ
>------------------------------------
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
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A leak in the hose right before the vacuum or at the other end letting
air into the bag?
Patrick
Harry James wrote:
air into the bag?
Patrick
Harry James wrote:
> They need air flow for cooling, make sure there is an air leak to insure
> cooling.
>
> HJ
>
On Fri, Dec 11, 2009 at 4:07 PM, eric14850 <eric14850@...> wrote:
sheets. (plus a 1 1/2" shoe, laminated on later, again from 1/2"
sheets.) Others will have their own opinions, but I was extremely
satisfied and happy with the ease and economy of this technique:
I built a central strong back rib, cut to the 'keel' curve shown on
the plans. The boat bottom being roughly 6 or 7 feet wide, the
plywood runs long ways across the boat, with joints alternated and
staggered 2 feet.
http://hallman.org/webcam/
Using an 10 inch drywall taping knife, I mixed enough epoxy (you get a
feel for it, about a quart +/1) and spread it liberally on the contact
surfaces, both sides, allowing enough extra to accommodate the fact
that some 'soaks' into the wood in the first 15 minutes. I then
flipped the one piece so wet to wet glue, and nailed the pieces
together.
I found it important to use those silicon bronze ring shank nails, 1d
#14 by 7/8". The ring shanks make them tighten up and hold, and the
silicon bronze allow them to be smoothed and worked with the belt
sander. Space them close enough to ensure zero voids, that was
roughly 8 inches on center. Add some more for the 'problem' spots.
Hammer nailing on floppy wood can be a challenge due to 'hammer head
bounce', but this is efficiently solved by holding a 'backing hammer'
underneath (I used a short handled 3lb maul).
The staggered 2 foot joints between the plywood layers did an
excellent job of smoothing out the bend of the curve. In a way, this
almost amounted to a type of butted scarf joint.
I considered using vacuum, but found the nailed method easier because
it allowed me to do the lamination layup just a piece at a time, which
was well suited for the 'spend an hour in the shop after work'
sequence of home building I favor. Also, I didn't see an easy way of
building the vacuum membrane around the curve of the strong back.
Other people have chosen to use a full strong back table, but I found
that just using the central strong back beam to work good enough. It
saved a lot of work (building and demolishing the table) and I was
able to adequately control the twist problem by using some
strategically placed 1" posts here and there. On a hull plate 1 inch
thick by 31 feet long and 7 feet wide, the whole thing remains floppy
until the sides are attached anyway. So some built in twist during the
layup is not really much worry, it all comes out later during the side
fit alignment anyway.
>The Topaz Spyder I built has a 1 inch bottom laminated from 1/2"
>
>
> I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences?
sheets. (plus a 1 1/2" shoe, laminated on later, again from 1/2"
sheets.) Others will have their own opinions, but I was extremely
satisfied and happy with the ease and economy of this technique:
I built a central strong back rib, cut to the 'keel' curve shown on
the plans. The boat bottom being roughly 6 or 7 feet wide, the
plywood runs long ways across the boat, with joints alternated and
staggered 2 feet.
http://hallman.org/webcam/
Using an 10 inch drywall taping knife, I mixed enough epoxy (you get a
feel for it, about a quart +/1) and spread it liberally on the contact
surfaces, both sides, allowing enough extra to accommodate the fact
that some 'soaks' into the wood in the first 15 minutes. I then
flipped the one piece so wet to wet glue, and nailed the pieces
together.
I found it important to use those silicon bronze ring shank nails, 1d
#14 by 7/8". The ring shanks make them tighten up and hold, and the
silicon bronze allow them to be smoothed and worked with the belt
sander. Space them close enough to ensure zero voids, that was
roughly 8 inches on center. Add some more for the 'problem' spots.
Hammer nailing on floppy wood can be a challenge due to 'hammer head
bounce', but this is efficiently solved by holding a 'backing hammer'
underneath (I used a short handled 3lb maul).
The staggered 2 foot joints between the plywood layers did an
excellent job of smoothing out the bend of the curve. In a way, this
almost amounted to a type of butted scarf joint.
I considered using vacuum, but found the nailed method easier because
it allowed me to do the lamination layup just a piece at a time, which
was well suited for the 'spend an hour in the shop after work'
sequence of home building I favor. Also, I didn't see an easy way of
building the vacuum membrane around the curve of the strong back.
Other people have chosen to use a full strong back table, but I found
that just using the central strong back beam to work good enough. It
saved a lot of work (building and demolishing the table) and I was
able to adequately control the twist problem by using some
strategically placed 1" posts here and there. On a hull plate 1 inch
thick by 31 feet long and 7 feet wide, the whole thing remains floppy
until the sides are attached anyway. So some built in twist during the
layup is not really much worry, it all comes out later during the side
fit alignment anyway.
My Elver, not a Bolger boat, a beutiful boat though it is has big box
plywood on the bottom and deck. I spent enough in extra glass and
plywood trying to protect cheap plywood that I may well have been
dollars ahead to use marine. Now I worry that such a handsome boat
won't last. I would say unless you just can't afford marine ply buy
it. Of course this is where somebody jumps in and says how their boat
is really old and its made of door panel's . Doug
Bill Howard wrote:
plywood on the bottom and deck. I spent enough in extra glass and
plywood trying to protect cheap plywood that I may well have been
dollars ahead to use marine. Now I worry that such a handsome boat
won't last. I would say unless you just can't afford marine ply buy
it. Of course this is where somebody jumps in and says how their boat
is really old and its made of door panel's . Doug
Bill Howard wrote:
>
>
> My personal experience with 5mm luan reminded me of Dynamite Payson's
> comment in one of his Instant Boat books, that he would as soon build
> a boat with shredded wheat.
>
>
> The luan available here tends to delaminate on the way home from Lowes.
>
> If you can't find good 1/4 inch ACX plywood, consider opening your
> piggy bank and buying 6 mm marine plywood. Yes, I know it costs about
> eight times as much as luan.
>
> Bill Howard
> Nellysford VA
> On Dec 11, 2009, at 7:07 PM, eric14850 wrote:
>
>>
>>
>> I'd be interested in hearing your technique for gluing full sheets of
>> plywood together and avoiding voids on hull sides or bottom.
>> Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a
>> bit of 1/2". My first attempt was unsatisfactory (voids). Next
>> attempt I used cement blocks covering nearly the entire surface which
>> worked.
>> Eric
>>
>> --- Inbolger@yahoogroups.com<mailto:bolger%40yahoogroups.com>,
>> "loosemoosefilmworks" <loosemoosefilmworks@...> wrote:
>> >
>> >
>> >
>> > The Loose Moose version of the AS39 (How I have always hated the
>> AS39 moniker) we built was 15mm (5/8") sides and deck with a triple
>> fifteen MM bottom.
>> >
>> > Bulkheads were all 15mm.
>> >
>> > All of the exterior was sheathed in two layers of 10 OZ cloth and
>> extra 10 oz tape was used at the chines
>> >
>> > If I was going to build it again I'd do the sides in two layers of
>> 10MM (3/8") which would have been handy on sveral level and make it
>> easier to build as well...
>> >
>> >
>> > Hope that helps
>> >
>> > Bob
>> >
>> >http://boatbits.blogspot.com/<http://boatbits.blogspot.com/>
>> >http://fishingundersail.blogspot.com/
>> <http://fishingundersail.blogspot.com/>
>> >http://islandgourmand.blogspot.com/
>> <http://islandgourmand.blogspot.com/>
>> >
>>
>
>
My personal experience with 5mm luan reminded me of Dynamite Payson's comment in one of his Instant Boat books, that he would as soon build a boat with shredded wheat.
The luan available here tends to delaminate on the way home from Lowes.
If you can't find good 1/4 inch ACX plywood, consider opening your piggy bank and buying 6 mm marine plywood. Yes, I know it costs about eight times as much as luan.
Bill Howard
Nellysford VA
On Dec 11, 2009, at 7:07 PM, eric14850 wrote:I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt I used cement blocks covering nearly the entire surface which worked.
Eric
--- Inbolger@yahoogroups. com, "loosemoosefilmwork s" <loosemoosefilmwork s@...> wrote:
>
>
>
> The Loose Moose version of the AS39 (How I have always hated the AS39 moniker) we built was 15mm (5/8") sides and deck with a triple fifteen MM bottom.
>
> Bulkheads were all 15mm.
>
> All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
>
> If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
>
>
> Hope that helps
>
> Bob
>
>http://boatbits. blogspot. com/
>http://fishingunder sail.blogspot. com/
>http://islandgourma nd.blogspot. com/
>
Here is a link to some articles on home vacuum stuff, if you scroll down
there are some articles on very cheap home made vacuum pumps.
http://www.belljar.net/articles.htm
HJ
Paul Hardy wrote:
there are some articles on very cheap home made vacuum pumps.
http://www.belljar.net/articles.htm
HJ
Paul Hardy wrote:
>
>
> The best way to glue two sheets of plywood flat on flat is by using a
> vacuum bagging system. A simple one can be set up using a shop vac and
> poly sheeting fastened around it. When I get to putting the bottom on
> Superbrick that is what I will be doing. Using a water trap between
> the vacuum and the bag will prevent having epoxy ruin the shop vac,
> though I recommend having at least one spare vacuum available as they
> don’t really like running for long periods and may crap out on you
> before the epoxy sets.
>
> Paul H
>
> I'd be interested in hearing your technique for gluing full sheets of
> plywood together and avoiding voids on hull sides or bottom.
> Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a
> bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt
> I used cement blocks covering nearly the entire surface which worked.
> Eric
>
>
>
>
They need air flow for cooling, make sure there is an air leak to insure
cooling.
HJ
Paul Hardy wrote:
cooling.
HJ
Paul Hardy wrote:
>
>
> The best way to glue two sheets of plywood flat on flat is by using a
> vacuum bagging system. A simple one can be set up using a shop vac and
> poly sheeting fastened around it. When I get to putting the bottom on
> Superbrick that is what I will be doing. Using a water trap between
> the vacuum and the bag will prevent having epoxy ruin the shop vac,
> though I recommend having at least one spare vacuum available as they
> don’t really like running for long periods and may crap out on you
> before the epoxy sets.
>
> Pa
>
>
Eric,
One more comment. If you can only get 3 psi of pressure differential that gives 432 pounds of pressure for every square foot. That could be equivalent to a lot of cinder blocks.
Sincerely,
Gene T.
On 11 Dec, 2009, at 7:07 PM, eric14850 wrote:
I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt I used cement blocks covering nearly the entire surface which worked.
Eric
--- In bolger@yahoogroups. com, "loosemoosefilmwork s" <loosemoosefilmwork s@...> wrote:
>
>
>
> The Loose Moose version of the AS39 (How I have always hated the AS39 moniker) we built was 15mm (5/8") sides and deck with a triple fifteen MM bottom.
>
> Bulkheads were all 15mm.
>
> All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
>
> If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
>
>
> Hope that helps
>
> Bob
>
> http://boatbits. blogspot. com/
> http://fishingunder sail.blogspot. com/
> http://islandgourma nd.blogspot. com/
>
Eric,
I'm working on a Micro Navigator. Bolger says that the bottom can be 1/4 or doubled to 1/2 or trippled to 3/4. Knowing that more is better, I went with 3 thicknesses of 1/4 inch ply. I vacuum bagged the second and third layers one panel at a time, 4 panels to a layer as per the plans. I offset each panel from the lower layer's seam so there won't be any weak areas. I ordered mastic tape sealant and used some thick plastic sheet we had laying around. I coated each surface to be mated with streight epoxy so it could soak in then using a notched trowel I applied epoxy thickened with milled glass and fumed silica. I used one or 2 shop vacs (in series) depending on possible leakage to insure sufficient vacuum. I have had to cut the hull for the rudder and found good coverage there and along the edges where I trimmed the plywood to shape. It requires mixing a low of epoxy for the thick filler so a slow epoxy is a necessity. I'd let things run for about 18 hours for each panel. I placed some thick carpet and old rope under the plastic to give good air flow to the vacuum. I also added some weights when I had doubts about a panel. Didn't do that to much.
I also built a Single Handed Schooner. I doubled the bottom on that, 2 x 3/8 MDO plywood. That one I used short Bronze boat nails in an array. Much less satisfying. Some broke through to the inside of the boat. If I do it again I definitely vacuum bag, even using my simple techniques.
Sincerely,
Gene T.
On 11 Dec, 2009, at 7:07 PM, eric14850 wrote:
I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt I used cement blocks covering nearly the entire surface which worked.
Eric
--- In bolger@yahoogroups. com, "loosemoosefilmwork s" <loosemoosefilmwork s@...> wrote:
>
>
>
> The Loose Moose version of the AS39 (How I have always hated the AS39 moniker) we built was 15mm (5/8") sides and deck with a triple fifteen MM bottom.
>
> Bulkheads were all 15mm.
>
> All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
>
> If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
>
>
> Hope that helps
>
> Bob
>
> http://boatbits. blogspot. com/
> http://fishingunder sail.blogspot. com/
> http://islandgourma nd.blogspot. com/
>
The best way to glue two sheets of plywood flat on flat is by using a vacuum bagging system. A simple one can be set up using a shop vac and poly sheeting fastened around it. When I get to putting the bottom on Superbrick that is what I will be doing. Using a water trap between the vacuum and thebag will prevent having epoxy ruin the shop vac, though I recommend having at least one spare vacuum available as they don’t really like running for long periods and may crap out on you before the epoxy sets.
Paul H
I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt I used cement blocks covering nearly the entire surface which worked.
Eric
I'd be interested in hearing your technique for gluing full sheets of plywood together and avoiding voids on hull sides or bottom. Experiences? Did you thicken the epoxy? I had 1/4" luan and needed a bit of 1/2". My first attempt was unsatisfactory (voids). Next attempt I used cement blocks covering nearly the entire surface which worked.
Eric
Eric
--- Inbolger@yahoogroups.com, "loosemoosefilmworks" <loosemoosefilmworks@...> wrote:
>
>
>
> The Loose Moose version of the AS39 (How I have always hated the AS39 moniker) we built was 15mm (5/8") sides and deck with a triple fifteen MM bottom.
>
> Bulkheads were all 15mm.
>
> All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
>
> If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
>
>
> Hope that helps
>
> Bob
>
>http://boatbits.blogspot.com/
>http://fishingundersail.blogspot.com/
>http://islandgourmand.blogspot.com/
>
The Loose Moose version of the AS39 (How I have always hated the AS39 moniker) we built was 15mm (5/8") sides and deck with a triple fifteen MM bottom.
Bulkheads were all 15mm.
All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
Hope that helps
Bob
http://boatbits.blogspot.com/
http://fishingundersail.blogspot.com/
http://islandgourmand.blogspot.com/
Bulkheads were all 15mm.
All of the exterior was sheathed in two layers of 10 OZ cloth and extra 10 oz tape was used at the chines
If I was going to build it again I'd do the sides in two layers of 10MM (3/8") which would have been handy on sveral level and make it easier to build as well...
Hope that helps
Bob
http://boatbits.blogspot.com/
http://fishingundersail.blogspot.com/
http://islandgourmand.blogspot.com/
can you tell me where you got that info?
--- Inbolger@yahoogroups.com, "Peter" <peterlenihan@...> wrote:
>
> 1/2" plywood throughout and doubled on the bottom at least for the AS-29.It may be a triple bottom on the AS-39,if not quadriple.
>
>
> Sincerely,
>
> Peter Lenihan
>
> --- Inbolger@yahoogroups.com, "w" <wdjdom@> wrote:
> >
> > does anyone know what the scantlings are for the bolger as29 and 39?
> >
>
1/2" plywood throughout and doubled on the bottom at least for the AS-29.It may be a triple bottom on the AS-39,if not quadriple.
Sincerely,
Peter Lenihan
Sincerely,
Peter Lenihan
--- Inbolger@yahoogroups.com, "w" <wdjdom@...> wrote:
>
> does anyone know what the scantlings are for the bolger as29 and 39?
>
does anyone know what the scantlings are for the bolger as29 and 39?