Does guerilla glue work in a vac bag? Im assuming no, because i think it reacts with air, but i have been wrong before. Dave
yeah it does dave, i have used it to glue 3mm mdf to my eps rocker beds wothout trouble to give them a durable skin(using the bag of course).However if you are planning on using it for boards, i would have a talk to paul cannon about it before you do it, as he has done some experimenting with this in the past as i understand it and can give you an idea as to the results.
It works, but it is problematic.
I only use it to attach nose/tail blocks. Skins and rails all get the epoxy resin treatment.
I’ve heard stories about it delamming on skins, and since it foams, any difference in application thickness makes a big difference in finished thickness. In my own experience, I wound up with lumpy rails because the it foamed up between the layers of balsa and got really thick in some sections.
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Does guerilla glue work in a vac bag? Im assuming no, because i think it reacts with air, but i have been wrong before. Dave
Davel,
What are you trying to do with it? The problem with GG glue is that it expands 3-4 times its layup volume. So if you are to do skins with it for instance, putting it on 1lb or less foam, all might look well on the skin side. Underneath the skin, however, the foam will have been violated by the expanding GG glue causing a structurally compromised board.
GG glue is a good product, but you need a path for the expanding glue to escape. While under vacuum you can’t accomplish this easily. Let us know what you are trying to pul off and maybe we can help you better.
<span style="font-weight:bold">dont use it stay whith epoxy
for otay compsands are not built in a mould
huie
@compsand.com
I should have specified, my mistake.
I am looking to use for a combo of Balsa/cork rails. I have already vacced down the skins with epoxy (went super smooth) but now working on building up the rails.
To the epoxy users (shwuz etc) - I would think you thicken up the epoxy with cabo/micro ballons or some sort, tape the rails in place, wrap in release, toss in the bag?
Right now im building them up with gorrila glue, and alot of tape, so i have decided there has to be a easier way.
Thanks for the responses, im going to post some pics up when they are done (6’6" and 6"2" fish)
Unfortunatly, my “water proof” camera was not so waterproof in jersey 2 weeks ago, so build pics right now are a no go.
Dave
the best glue for that work is titebond they do a water proof one
huie
@compsand.com
GG can have it’s place in compsands, but it’s troublesome.
It’s very useful for repairs…
As Huie says, stick with epoxy (ha ha punny)
-GG is moisture curing, so you can control the foaming with how much moisture it is exposed to.
Vac bag = not much moisture from the atmosphere, only what is integral in the materials you are using.
This attribute can be used to you advantage if you’re creative
-Never use GG without some form of clamping, eg vac bag, G-clamps, etc. The expanding can be quite strong - i’d be very scared using it for rails!
Yes to cabosil (collodial silica) in lam epoxy - works great for rails
Hope this helps man
The problem with GG glue is that it expands 3-4 times its layup volume.
True, if you use it straight out of the bottle. Not true otherwise.
it reacts with water more than it does with air
we used to use it all the time gluing uo blanks and skins
the problem is with the uncontrolled expansion more than anything else
Benny did more experimenting with this stuff in the early days than anyone else
check the archives
you’ve got to go thin
always thought if you could get the stuff as a thin film or impregnated i cloth than you could cut apply and then activate with water. Then you might solve the uneven expansion issue
You could probably build your own with one of those 2 foot wide industrial wax paper rolls a and a good wide squeegie and an airtight wrapper. Still yet they could just as well make these in a factory.
The one thing that needs air that’s way better than PU glue as far as user friendly handling is “Roo Glue”. CMP turned me on to that years ago for glung up stringers to foam blanks he even colored it with food dye so he would know the densities.
The air problems were more with elmers when gluing up sheets into blanks than anything else from what I remember. Right Shwuz? But those were the cave man days before everyone got into hotwiring… Used to be foam planks, elmers and a bunch of books in the living room somewhere.
the rail build up is the bane of compsands.
it’s probably too late, but consider preserving your offcuts for next time.
even this set up is tricky and is best done with 2 sets of hands and a lot
of preparation.
ps. cork is banned from my shop…it’s a nightmare at each step in the process.
Good memory, oneula! Yeah, Elmer’s resulted in the only delam one of my boards has ever suffered. Caveman days, indeed.
I don’t even thicken up my rail epoxy with cabosil. I just brush it on straight as mixed. I figure the balsa strips are flat, so they shouldn’t need any bulk between layers, just a thin and even layer of adhesive. Any excess squeezes out between the strips, and I’m left with the minimum necessary to stick them together. I would think that having thicker layers of epoxy would make the rails even harder to shape out. God knows we don’t need that!
But yeah, cut rail strips to shape, brush on epoxy, tape to blank, wrap with release film, throw in vac bag.
hey guys its time to throw out that amature way of building rails
you will have to go back to wooden boatbuilding to do this in the correct maner.
huie
@compsand.com
Hey Dave,
I use ResinX for veneering bamboo in the bag. It’s thick and really tacky so I wet up the blank and veneer, position the veneer with alignment marks hopefully getting it right the first time becasue it doesn’t want to come off real easily. That being the case I don’t use any tape at all - just slide it into the bag and pull vac. Take it out in about and hour and start lamming.
~Brian
sorry didn’t see that part about balsa cork rails.
it that’s the case I’d stay away from epoxy cause you’ll have problems finishing the rails later because of the hard and soft layers.
you need to make sure the layers will cut and sand off around the same density otherwise you’re gonna get ridges.
that’s why I think alot of us have migrated to full band wood or high density foam rails cause it’s much easier to turn and fine finish the rails.
for that combo I would follow huie’s advice and go with waterproof titebond 3 in a bag.
there’s also some industrial binders contruction guys use for doing floors and walls that’ll work too. but the glue line should cut under a sureform or screen the same as the substrate or you will get uneveness. I think that why the hollow guys use GG or titlebond for the rails. Then again they use tack nails as well to hold their strip and feather method pieces i place.
if you don’t want to use a bag.
slice up an inner tube and use that as your clamp.
wrap it around tightly and tie it off.
hope this helps
I use fast PU for the first rail to foam bond, then super glue from then on.
Quote:
I should have specified, my mistake.I am looking to use for a combo of Balsa/cork rails. I have already vacced down the skins with epoxy (went super smooth) but now working on building up the rails.
To the epoxy users (shwuz etc) - I would think you thicken up the epoxy with cabo/micro ballons or some sort, tape the rails in place, wrap in release, toss in the bag?
Right now im building them up with gorrila glue, and alot of tape, so i have decided there has to be a easier way.
Thanks for the responses, im going to post some pics up when they are done (6’6" and 6"2" fish)
Unfortunatly, my “water proof” camera was not so waterproof in jersey 2 weeks ago, so build pics right now are a no go.
Dave
Next build try doing the rails first prior to the skins. It looks way cleaner. There are many ways to do this but the simple explanation is to template the board outline and have perpendicular rails, finish the bottom all the way or 90% complete. Tape, clamp, vac,(however you can manage this) wood or cork rails on. Finish bottom all the way with your wood rails flush and matching the bottom only. Vacuum bottom skin on then finish the deck and rails and then do the top skin. When you get more proficient you can do the bottom skin and the rails in the same vac pull and and then continue as described above.
good to know your rail builds are done in the amature way.
huie
@compsand.com
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good to know your rail builds are done in the amature way.huie @compsand.com
It is how RF did um in 1984. I don’t want to discourage an up and comer in the compsand community the best way to do it. Limited resources and equipment dictate the answer.
Hey DaveL, go to compsand.com, those guys have all the answers there.
I am curious why people still come to sways for compsand advice? When someone asks compsand question should they automatically be routed to your site??? Kind of like “check the archives” response??
1984 jez this is the 21 century
thanks for the plug
yes you can get good advice @co</span><span style="font-weight:bold">mpsand.com
huie
@compsand.com