Re: Vac pumps - was scarfing bottom flooring
> For plywood, I use a shopvac, the cheapest model they have is finethat
> (qsp is cheap and easy on the ears), it will pull down everything,
> except possibly an inch around the edge, so you need to plan for
> with a little overhang.Is there an online primer for home vac. bagging?
A list of simple instructions and equipment?
I have a shop vac and an automotive AC vacuum pump.
Charles
--- Inbolger@yahoogroups.com, "Roger Derby" <derbyrm@s...> wrote:
(qsp is cheap and easy on the ears), it will pull down everything,
except possibly an inch around the edge, so you need to plan for that
with a little overhang. Your first layer should have a few inches of
overhang so that you have a place for the caulk. Shopvacs need
approx 4 x 1/4" holes in whatever pipe you are using, placed outside
the bag, so a constant supply of flresh air is cooling the motor, at
all times. With this kind of pressure, you get very even results,
with just resin, no fillers, coat bothe sheets thoroughly, but not
heavily ytou can do as many layers as you like at once. This pump
will hold down flat or curved material, as long as the bend isn't
extreme, it's basicaly a contact pressure thing. You can also bag
fabric this way, and scarph joints. I have done 24x4 witht his.
You can of course also use various rotary vane systems, like milking
machine, refrigeration, printing vac pumps. These usualy team an
induction motor, and the pump mechanism. usualy one can find cheap
units if one looks for them, however OEM units can go up to 500+
dollars. They pull less air, though at higher pressures. These
pressures are necesary using non-epoxy glues like elmer's white, and
stuff like birdeye veneer. They genraly aren't all that useful for
wood epoxy building, where the panels a smooth, and any fabirc lams
tend to be single layer, or at least not require moving a lot of
resin around.
> What kind of pump(s) do you use for a 17 foot by 5 foot vacuumbagging job?
> Seriously.For plywood, I use a shopvac, the cheapest model they have is fine
>
(qsp is cheap and easy on the ears), it will pull down everything,
except possibly an inch around the edge, so you need to plan for that
with a little overhang. Your first layer should have a few inches of
overhang so that you have a place for the caulk. Shopvacs need
approx 4 x 1/4" holes in whatever pipe you are using, placed outside
the bag, so a constant supply of flresh air is cooling the motor, at
all times. With this kind of pressure, you get very even results,
with just resin, no fillers, coat bothe sheets thoroughly, but not
heavily ytou can do as many layers as you like at once. This pump
will hold down flat or curved material, as long as the bend isn't
extreme, it's basicaly a contact pressure thing. You can also bag
fabric this way, and scarph joints. I have done 24x4 witht his.
You can of course also use various rotary vane systems, like milking
machine, refrigeration, printing vac pumps. These usualy team an
induction motor, and the pump mechanism. usualy one can find cheap
units if one looks for them, however OEM units can go up to 500+
dollars. They pull less air, though at higher pressures. These
pressures are necesary using non-epoxy glues like elmer's white, and
stuff like birdeye veneer. They genraly aren't all that useful for
wood epoxy building, where the panels a smooth, and any fabirc lams
tend to be single layer, or at least not require moving a lot of
resin around.
> I've been trying to get set up, but so far I just haven't gottenthe whole
> rig to work at one time.gives a
>
> Stapling thru a scrap of the plastic strapping used by shippers
> better chance of getting hold of the staple with diagonal cutterswhen it's
> time to pull it out. (I'd hoped I could just grab the tape andpull, but
> the staples won.)least
>
> Roger
> derbyrm@s...
>http://derbyrm.mystarband.net
>
> ----- Original Message -----
> From: "proaconstrictor" <proaconstrictor@y...>
>
> > This doesn't sound like your method has anythign to do with actual
> > scarfing. You are just asking how to laminate the bottom?
> >
> > If you want to scarf it, try scarfing layer one, and leave at
> > 3" overhang running all around it, then vac bag the other twogood
> > layers. Nothing makes a joint like vac baggin. 1/4 inch is a
> > choice since you can cut scarph to finished dimensions with a71/4"
> > saw. Or you can grind them.is
> >
> > Not all luan uses waterproof glue, and some that does isn't
> > waterproof when soaked for a while, while real 1088 is. There are
> > also waterproofness issues with Dfir AC, such as voids, and
> > insuficient glue. I've been doing a fair bit of survey work this
> > year, and I'm finding a lot of depressing problems (the good news
> > they are just as likely in boats costing 100 bucks, as 100K).With
> > that in mind, I am redoubling efforts to seal edges, you needglass
> > wraping, and I've seen a lot of fasteners causing problems bylove
> > providing pathways for water. Which is really too bad since I
> > my staple gun.
What kind of pump(s) do you use for a 17 foot by 5 foot vacuum bagging job?
Seriously.
I've been trying to get set up, but so far I just haven't gotten the whole
rig to work at one time.
Stapling thru a scrap of the plastic strapping used by shippers gives a
better chance of getting hold of the staple with diagonal cutters when it's
time to pull it out. (I'd hoped I could just grab the tape and pull, but
the staples won.)
Roger
derbyrm@...
http://derbyrm.mystarband.net
Seriously.
I've been trying to get set up, but so far I just haven't gotten the whole
rig to work at one time.
Stapling thru a scrap of the plastic strapping used by shippers gives a
better chance of getting hold of the staple with diagonal cutters when it's
time to pull it out. (I'd hoped I could just grab the tape and pull, but
the staples won.)
Roger
derbyrm@...
http://derbyrm.mystarband.net
----- Original Message -----
From: "proaconstrictor" <proaconstrictor@...>
> This doesn't sound like your method has anythign to do with actual
> scarfing. You are just asking how to laminate the bottom?
>
> If you want to scarf it, try scarfing layer one, and leave at least
> 3" overhang running all around it, then vac bag the other two
> layers. Nothing makes a joint like vac baggin. 1/4 inch is a good
> choice since you can cut scarph to finished dimensions with a 71/4"
> saw. Or you can grind them.
>
> Not all luan uses waterproof glue, and some that does isn't
> waterproof when soaked for a while, while real 1088 is. There are
> also waterproofness issues with Dfir AC, such as voids, and
> insuficient glue. I've been doing a fair bit of survey work this
> year, and I'm finding a lot of depressing problems (the good news is
> they are just as likely in boats costing 100 bucks, as 100K). With
> that in mind, I am redoubling efforts to seal edges, you need glass
> wraping, and I've seen a lot of fasteners causing problems by
> providing pathways for water. Which is really too bad since I love
> my staple gun.
How old? I do have some old interior stuff that delaminates if it's foggy
out, but I bought it over 40 years ago.
I have the impression that the industry switched about 20 years ago, but ...
who knows about any individual factory. There are a lot of different
companies making plywood. If you got the overrun from an order produced for
a furniture factory ...
For boats, I wouldn't use anything that didn't have "exterior" stamped on
it. If you're still doubtful, some put a scrap in the dishwasher for
multiple cycles.
Roger
derbyrm@...
http://derbyrm.mystarband.net
out, but I bought it over 40 years ago.
I have the impression that the industry switched about 20 years ago, but ...
who knows about any individual factory. There are a lot of different
companies making plywood. If you got the overrun from an order produced for
a furniture factory ...
For boats, I wouldn't use anything that didn't have "exterior" stamped on
it. If you're still doubtful, some put a scrap in the dishwasher for
multiple cycles.
Roger
derbyrm@...
http://derbyrm.mystarband.net
----- Original Message -----
From: <lincolnr@...>
To: <bolger@yahoogroups.com>
Sent: Monday, October 06, 2003 10:34 PM
Subject: [bolger] Re: scarfing bottom flooring
>
> I wish you would speak to some of my sheets of plywood and an old boat I
> used to won. They haven't heard.
> Roger Derby wrote:
> >I've been given the impression that all plywood uses "exterior" grade
glue
> >anymore, so it shouldn't delaminate, particularly if you seal the outside
> >with epoxy. Soak the edges real well.
> snip
>
This doesn't sound like your method has anythign to do with actual
scarfing. You are just asking how to laminate the bottom?
If you want to scarf it, try scarfing layer one, and leave at least
3" overhang running all around it, then vac bag the other two
layers. Nothing makes a joint like vac baggin. 1/4 inch is a good
choice since you can cut scarph to finished dimensions with a 71/4"
saw. Or you can grind them.
Not all luan uses waterproof glue, and some that does isn't
waterproof when soaked for a while, while real 1088 is. There are
also waterproofness issues with Dfir AC, such as voids, and
insuficient glue. I've been doing a fair bit of survey work this
year, and I'm finding a lot of depressing problems (the good news is
they are just as likely in boats costing 100 bucks, as 100K). With
that in mind, I am redoubling efforts to seal edges, you need glass
wraping, and I've seen a lot of fasteners causing problems by
providing pathways for water. Which is really too bad since I love
my staple gun.
scarfing. You are just asking how to laminate the bottom?
If you want to scarf it, try scarfing layer one, and leave at least
3" overhang running all around it, then vac bag the other two
layers. Nothing makes a joint like vac baggin. 1/4 inch is a good
choice since you can cut scarph to finished dimensions with a 71/4"
saw. Or you can grind them.
Not all luan uses waterproof glue, and some that does isn't
waterproof when soaked for a while, while real 1088 is. There are
also waterproofness issues with Dfir AC, such as voids, and
insuficient glue. I've been doing a fair bit of survey work this
year, and I'm finding a lot of depressing problems (the good news is
they are just as likely in boats costing 100 bucks, as 100K). With
that in mind, I am redoubling efforts to seal edges, you need glass
wraping, and I've seen a lot of fasteners causing problems by
providing pathways for water. Which is really too bad since I love
my staple gun.
If there's much rocker to the bottom, one would need a VERY strong building
frame, well anchored to a thick concrete floor, together with some eyebolts
anchored to the concrete for the come-a-long(s) which you'll need to get the
ends down. The sheer clamps would also have to be strong, as would the
deck, because the strain in the hull will persist long after the epoxy sets.
Roger
derbyrm@...
http://derbyrm.mystarband.net
frame, well anchored to a thick concrete floor, together with some eyebolts
anchored to the concrete for the come-a-long(s) which you'll need to get the
ends down. The sheer clamps would also have to be strong, as would the
deck, because the strain in the hull will persist long after the epoxy sets.
Roger
derbyrm@...
http://derbyrm.mystarband.net
----- Original Message -----
From: "Peter Lenihan" <lestat@...>
> --- Inbolger@yahoogroups.com, Mi'ki <mike78612003@y...> wrote:
> > for a 3/4 inch flooring on the boat (I need five feet wide and 17
> feet long) I plan on putting 1/4 ply over a mold form and then take
> epoxy and two more of 1/4 ply sheets on top and using heavy sand bags
> until cured.
>
> I'm not too sure I follow this but it sounds like it would be a whole
> lot quicker/cheaper to just use straight 3/4" ply to begin with and
> scarf them to the desired length........it can even be bought in 5'
> widths :-)
> Then again,who am I to spoil someones fun!
>
> Sincerely,
>
> Peter Lenihan
--- Inbolger@yahoogroups.com, Mi'ki <mike78612003@y...> wrote:
epoxy and two more of 1/4 ply sheets on top and using heavy sand bags
until cured.
the floor gets wet and just how heavy should the sheets of ply be
torqued together
I'm not too sure I follow this but it sounds like it would be a whole
lot quicker/cheaper to just use straight 3/4" ply to begin with and
scarf them to the desired length........it can even be bought in 5'
widths :-)
Then again,who am I to spoil someones fun!
Sincerely,
Peter Lenihan
> for a 3/4 inch flooring on the boat (I need five feet wide and 17feet long) I plan on putting 1/4 ply over a mold form and then take
epoxy and two more of 1/4 ply sheets on top and using heavy sand bags
until cured.
>is the glue that holds the three ply wood together going to hold if
> (not using the expensive marine grade plywood) On regular ply a/c
the floor gets wet and just how heavy should the sheets of ply be
torqued together
I'm not too sure I follow this but it sounds like it would be a whole
lot quicker/cheaper to just use straight 3/4" ply to begin with and
scarf them to the desired length........it can even be bought in 5'
widths :-)
Then again,who am I to spoil someones fun!
Sincerely,
Peter Lenihan
>
> [Non-text portions of this message have been removed]
I've been given the impression that all plywood uses "exterior" grade glue
anymore, so it shouldn't delaminate, particularly if you seal the outside
with epoxy. Soak the edges real well.
Epoxy doesn't need clamping pressure for the bond, but you do need to apply
enough pressure to ensure that there are no voids. What's that old line?
"It's not the glue in the joint that holds it together, it's the stuff that
squeezes out the edges." Too much pressure will starve the joint of epoxy
and make it weaker.
Typically one puts the thickened epoxy on with a notched trowel. I use
"wood flour" for a thickener for bonding. It's thixotropic so you don't
have to have any other additives. (Be sure to mix the resin and hardener
thoroughly before adding the thickener.)
Dry wall screws or pneumatic staples seem to be popular for laminating. On
the dinghy, the designer called for pan head SS sheet metal screws. The dry
wall screws are easiest to get out.
In a couple of places on the dinghy, the epoxy bonded a screw in too tight
and I had to heat the screw to get it out. I used a propane torch, but you
need a wet rag handy to snuff out any fires you start. There's probably a
better way to apply the heat.
Roger
derbyrm@...
http://derbyrm.mystarband.net
anymore, so it shouldn't delaminate, particularly if you seal the outside
with epoxy. Soak the edges real well.
Epoxy doesn't need clamping pressure for the bond, but you do need to apply
enough pressure to ensure that there are no voids. What's that old line?
"It's not the glue in the joint that holds it together, it's the stuff that
squeezes out the edges." Too much pressure will starve the joint of epoxy
and make it weaker.
Typically one puts the thickened epoxy on with a notched trowel. I use
"wood flour" for a thickener for bonding. It's thixotropic so you don't
have to have any other additives. (Be sure to mix the resin and hardener
thoroughly before adding the thickener.)
Dry wall screws or pneumatic staples seem to be popular for laminating. On
the dinghy, the designer called for pan head SS sheet metal screws. The dry
wall screws are easiest to get out.
In a couple of places on the dinghy, the epoxy bonded a screw in too tight
and I had to heat the screw to get it out. I used a propane torch, but you
need a wet rag handy to snuff out any fires you start. There's probably a
better way to apply the heat.
Roger
derbyrm@...
http://derbyrm.mystarband.net
----- Original Message -----
From: "Mi'ki" <mike78612003@...>
> for a 3/4 inch flooring on the boat (I need five feet wide and 17 feet
long) I plan on putting 1/4 ply over a mold form and then take epoxy and
two more of 1/4 ply sheets on top and using heavy sand bags until cured.
>
> (not using the expensive marine grade plywood) On regular ply a/c is the
glue that holds the three ply wood together going to hold if the floor gets
wet and just how heavy should the sheets of ply be torqued together
I would think that you might want to screw each layer down until it is
cured and then fill the hole that the screw leave after they are
removed. I don't think sand bagging it will give you enough even
prssure all across the gluing surface.
Do you plan on staggering your joints of the 1/4" layers? At the
minimun I would stagger the joints by 2'.
Corbin
Draco the Red
Captain of the Small boats
Owner/builder Auray Brick
cured and then fill the hole that the screw leave after they are
removed. I don't think sand bagging it will give you enough even
prssure all across the gluing surface.
Do you plan on staggering your joints of the 1/4" layers? At the
minimun I would stagger the joints by 2'.
Corbin
Draco the Red
Captain of the Small boats
Owner/builder Auray Brick
--- Inbolger@yahoogroups.com, Mi'ki <mike78612003@y...> wrote:
> for a 3/4 inch flooring on the boat (I need five feet wide and 17
feet long) I plan on putting 1/4 ply over a mold form and then take
epoxy and two more of 1/4 ply sheets on top and using heavy sand bags
until cured.
>
> (not using the expensive marine grade plywood) On regular ply a/c is
the glue that holds the three ply wood together going to hold if the
floor gets wet and just how heavy should the sheets of ply be torqued
together
>
>
> ---------------------------------
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> The New Yahoo! Shopping - with improved product search
>
> [Non-text portions of this message have been removed]
for a 3/4 inch flooring on the boat (I need five feet wide and 17 feet long) I plan on putting 1/4 ply over a mold form and then take epoxy and two more of 1/4 ply sheets on top and using heavy sand bags until cured.
(not using the expensive marine grade plywood) On regular ply a/c is the glue that holds the three ply wood together going to hold if the floor gets wet and just how heavy should the sheets of ply be torqued together
---------------------------------
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
[Non-text portions of this message have been removed]
(not using the expensive marine grade plywood) On regular ply a/c is the glue that holds the three ply wood together going to hold if the floor gets wet and just how heavy should the sheets of ply be torqued together
---------------------------------
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
[Non-text portions of this message have been removed]