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ron ll
10-06-2016, 01:27 PM
Any tricks? I have two pieces about 4' x 7' with a couple of cutouts. It is 10 oz. cloth over new marine plywood. It has been my experience in the past that the squeegee will tend to move the cloth. You can continue to squeegee it back until you finally get it where you want it, but it sure would be simpler if it stayed put in the first place. I'll lay it dry and spread epoxy over it. I suppose I could put a couple of staples at strategic corners as long as the staples were well sunk below the surface and then just epoxy over them. Is that a bad idea? Other ideas?

Ian McColgin
10-06-2016, 01:32 PM
Lots of people have different approaches depending on the exact application. My general go-to is to put down a thin layer of epoxy, let it start curing to get a bit sticky to hold the glass even on a vertical, lay (maybe with a roller's help to push it down) the cloth on and let that get close enough to cured that the glass won't move as I work more epoxy in to fill the weave.

Before it begins to tack, epoxy is a fantastic lubricant, as you're discovering.

Gib Etheridge
10-06-2016, 01:40 PM
It pays to seal the ply with epoxy first, otherwise displaced air in the grain will cause bubbling.

I think you're doing horizontal surfaces, yes? I use the Gougeon Bros. foam rollers. If you want to use the squeegee use it once the resin has been rolled on.

ron ll
10-06-2016, 01:52 PM
Yes, horizontal surfaces. I like the roller idea. You may be right about sealing it first. I'm starting to panic because it is getting harder to find two dry days in a row and this work area is difficult to tarp. So maybe combining sealing the plywood with Ian's suggestion of putting the cloth on a tacky surface is the way to go.

Gib Etheridge
10-06-2016, 01:58 PM
Should work OK. You'll get bubbles in the sticky coat, but you can squeegee them out as it approaches stickiness. Since I'm never fanatic about the weight I don't use a squeegee after saturating the glass. You can control resin thickness quite well with the roller, and you want to fill the weave anyway.

ron ll
10-06-2016, 02:03 PM
I think I'll dispense with the squeegee, the roller seems to make a lot more sense. But now it dawned on me that setting the cloth on a tacky surface is kind of like setting p-lam on contact cement, getting it in the right place at first might be a little tricky. So if I seal the plywood and let it cure before placing the cloth dry, do I have to deal with blush (West system)?

Ian McColgin
10-06-2016, 02:15 PM
In general, it's good to put a thin sealer coat on plywood and let that cure. Wash to remove blush and then light sand to give the next bit some tooth. This will solve your air bubbles issues.

How sticky you let it cure before you lay the glass on is context dependent. The flatter the surface the less the worry and as you get closer to working on a vertical surface, it gets easier to work top down and let gravity keep the piece hanging right.

I then don't fill the weave till the under coat is nearly cured and holding the glass firmly. Catch it before the cure and no blush problems. Or use a non-blushing epoxy. Personally for this coat I squeegee and roller very aggressivly to put as little epoxy in as fully wets the glass. When this cures the surface will have the weave's texture but the glass is against the wood surface. If you put it on thick, the glass just floats up a bit and it's much harder to get a smooth clean finish. Once that part's cured, wash, light sand, and epoxy filler coat.

G'luck

Gib Etheridge
10-06-2016, 02:17 PM
Supposedly not, if you glass it within 24 hours of sealing it, but I do anyway to be safe. That may be difficult for you though, because it will be hard to dry it once you've washed it this time of year.

If you have your glass dry-fitted and oversized you can roll it up, apply the sticky coat then carefully unroll it back into place. It is tricky though, and if the sticky resin soaks into the glass a little bit then hardens before you can wet it all out you'll get areas that don't wet out well.

I would do the extra work of tarping it well and applying heat from below during the entire process, which would be sealing it, squishing out the bubbles, letting it cure for a couple of days, washing and drying it, light sanding, then glassing and tipping out any bubbles that form until it gets sticky, then applying another coat of resin while still sticky. Using the squeegee to squish the bubbles refills some of the pin holes.

Canoez
10-06-2016, 02:59 PM
Supposedly not, if you glass it within 24 hours of sealing it, but I do anyway to be safe. That may be difficult for you though, because it will be hard to dry it once you've washed it this time of year.

If you have your glass dry-fitted and oversized you can roll it up, apply the sticky coat then carefully unroll it back into place. It is tricky though, and if the sticky resin soaks into the glass a little bit then hardens before you can wet it all out you'll get areas that don't wet out well.

I would do the extra work of tarping it well and applying heat from below during the entire process, which would be sealing it, squishing out the bubbles, letting it cure for a couple of days, washing and drying it, light sanding, then glassing and tipping out any bubbles that form until it gets sticky, then applying another coat of resin while still sticky. Using the squeegee to squish the bubbles refills some of the pin holes.

If you're going to "hot coat" the epoxy, you want it to set up just to the point where the first coat has cured that it will not come up on your gloved finger when you touch it. It should still be "green". This way you get a good chemical bond between the layers. I would hope you're using a "blush free" resin system anyway.

Ian McColgin
10-06-2016, 03:01 PM
Matching glass panels can be a pain. I overlap them and at the last chance of tack but still can pull away I slice down the middle of the overlap, peel off the upper strip, lift the remaining upper enough to peel off the lower strip, and put it all back down cut edge to cut edge. It's a little tricky but beats grinding off overlap.

ron ll
10-06-2016, 03:23 PM
Thanks all, this is very helpful. I've done it before a couple of times but at a better time of year and decks that were a little easier to access. Part of the problem with this is it is the roof of the pilot house and once I start spreading epoxy, most of the work will have to be done from a ladder without a lot to hang onto that isn't sticky. I plan on having a center overlap of about 8" or 10". I'm not too worried about the ridges visually and I can taper them out by sanding a bit anyway.

Since this picture, the edges have been trimmed flush and rounded over and seams have been taped. There will be a 1-1/2" bullnose trim over the edge of the glass.

http://i1171.photobucket.com/albums/r560/ron_ll/F4DD0A6A-9433-4672-8D6D-68869D8AD9F4_zpsouu0gv9b.jpg

Canoez
10-06-2016, 03:38 PM
rollers should work for you. Barring that, a thinner than average poly spreader and a delicate touch should work for you. Working from the stack out, the wet-out areas should help hold the cloth in place. The ladders? Man. That might be a trick. How much side deck is on her?

jackster
10-06-2016, 03:51 PM
This is what I would do...
lay cloth in place...
Carefully fold 1/2 back on top of other half (I would do this fore and aft)...
Roll on a layer of mixed resin on the bare, exposed ply, making sure it is as even as possible...
Let is sit for 5 minutes and add resin to dry spots...
CAREFULLY re-place the folded half. Resin should be wet enough to allow for some adjustment..
Smooth but do not saturate that half...
Fold dry half over wetish half and apply resin to remaining raw ply...
Fold the loose half back...
Adjust cloth and add more resin with the roller to fill the weave to all of the surface.
Roll slowly so as not to disturb the cloth too much.
This should take less than an hour, so you should have plenty of time with slow hardener..
Good luck... :)

ron ll
10-06-2016, 03:52 PM
rollers should work for you. Barring that, a thinner than average poly spreader and a delicate touch should work for you. Working from the stack out, the wet-out areas should help hold the cloth in place. The ladders? Man. That might be a trick. How much side deck is on her?

Just enough to keep me from falling over backwards. :D Actually, it is not that bad, it's a short ladder that I can tie to the grab rail. There is enough slope to it that I'm comfortable with it. If I open the pilot house windows that will give me something to hold onto.

Richard Smith
10-06-2016, 04:04 PM
In addition to the above, here are some ideas for your consideration:

Using heat, foam rollers, and a very flexible squeegee. (I make similar squeegees from gallon ice cream container covers.)
http://www.laughingloon.com/epoxy.html

Getting and keeping things in place:

Part 1
http://www.youtube.com/watch?v=WdaPecHY4VQ&list=PLzlN3A2DLgNz7vh_8Hur0N7ICHnt0Rt1n&sns=em

Part 2
http://www.youtube.com/watch?v=cf6eHN9htsY&list=PLzlN3A2DLgNz7vh_8Hur0N7ICHnt0Rt1n&sns=em

ron ll
10-06-2016, 04:48 PM
Thanks for the links. I noticed he was hand sanding the epoxy and sweeping the dust off without any mask at all. Not sure I get that.

Gib Etheridge
10-06-2016, 04:52 PM
This is what I would do...
lay cloth in place...
Carefully fold 1/2 back on top of other half (I would do this fore and aft)...
Roll on a layer of mixed resin on the bare, exposed ply, making sure it is as even as possible...
Let is sit for 5 minutes and add resin to dry spots...
CAREFULLY re-place the folded half. Resin should be wet enough to allow for some adjustment..
Smooth but do not saturate that half...
Fold dry half over wetish half and apply resin to remaining raw ply...
Fold the loose half back...
Adjust cloth and add more resin with the roller to fill the weave to all of the surface.
Roll slowly so as not to disturb the cloth too much.
This should take less than an hour, so you should have plenty of time with slow hardener..
Good luck... :)

Hey, I like that! Maybe a sealer coat first.

Canoez
10-06-2016, 04:59 PM
I'm a fond fan of the sealer coat. Particularly in a situation where you have little control over the ambient temperature. If the temperature of the surface that you're applying the epoxy to is falling as you apply the epoxy you're ok. If the temperature of the surface is rising (i.e. in the sun) you'll get a million bubbles from the off-gassing of the wood. So, if you can pre-seal the wood with epoxy before you apply the cloth, you'll avoid that issue for the most part. The added benefit is that it makes the surface smoother and you're less likely to snag the cloth.

Ron - will you be adding pigment to the resin?

ron ll
10-06-2016, 05:04 PM
I hadn't considered pigment. Should I? What's it's purpose?

Ian McColgin
10-06-2016, 05:06 PM
You'll need to paint it no matter what, but the advantage of pigmented epoxy is stronger clearer color on the final coat. If that matters, which with many paints it really does not.

WI-Tom
10-06-2016, 06:17 PM
This is an interesting thread--I glassed my hull this summer with my brother's help and didn't notice any trouble getting the cloth to stay in place at all. We laid the cloth on dry, then poured epoxy over it and used plastic squeegees to carefully draw the resin along the hull. (We did use rollers on later coats to fill the weave). Starting in the center beside the flat keel and carefully working our way outward and downward seemed to do the trick with no problems. One piece of glass for each side of the hull, and the keel glassed separately.

http://i1022.photobucket.com/albums/af343/WI-Tom/Boat%20pictures/Alaska%20build/DSCN2557.jpg (http://s1022.photobucket.com/user/WI-Tom/media/Boat%20pictures/Alaska%20build/DSCN2557.jpg.html)

Anyone have any thoughts on why some have trouble with this? It seemed pretty simple in practice, even on my fairly curvy hull, though 2 people (one mixing, one spreading) certainly made the job easier, as I didn't have slow hardener. On that flat coach roof it seems like it should be simple to put the cloth down dry.

We also did not pre-coat the hull, though we were careful about avoiding rising temps.

Tom

wizbang 13
10-06-2016, 06:56 PM
Switch from glass to dynel .

ron ll
10-06-2016, 07:43 PM
Switch from glass to dynel .

Too late, but why? The only advantage I saw was abrasion resistance. As I plan to keep this side of the boat up and away from really low bridges, I didn't see the point. :)

wizbang 13
10-06-2016, 07:49 PM
Dynel offers more than abrasion resistance. It will move a bit more than fg. It will be more forgiving to the cycles of movement wood in the future, which, jah willing, will be only shrinking .And of course there is not itching. You are y seek to make the deck waterproof, not to add strength , so why use fg?

PeterSibley
10-06-2016, 08:59 PM
On a surface like your cabin top I'd use a little masking tape over he edges ..... to hold things in place ,assuming you think the wind might kick up. Depending on whether you want a "textured "finish or dead smooth I'd consider a layer of peel ply . It gives an excellent surface finish that won't require sanding. http://www.clcboats.com/shoptips/epoxy_and_fiberglass/peel-ply-release-fabric.html

It cost a little, not much at all if you time is worth anything and you'd like to avoid sanding so you can paint sooner.

RFNK
10-07-2016, 05:40 AM
Outgassing is a real problem. I never glass in rising temperatures or on surfaces likely to have sunshine on them before the resin sets. But I think the pre-coat system is too laborious and uses too much resin. I find laying glass on horizontal surfaces and spreading with a squeegee or card is really straightforward. As soon as the resin is spread onto the glass, it grips the surface very well. Pools and big bubbles are easily fixed with a little ribbed roller. I haven't tried the foam rollers for glassing - I should, I guess.

I find vertical surfaces more challenging. While it's easier to achieve a nice thin saturating coat on the glass, the top edges can slump. Tape can work but for a hull that I've been procrastinating about for years that I'm going to sheathe soon, I'm going to try plastic staples. They wouldn't suit all situations but the ply hull I'm going to sheathe has 1/2 inch ply that is fairly soft, so I think it should work. The staples don't penetrate far.

Peel ply is really great stuff and well worth the expense. The finish it achieves is very even and a breeze to sand.

Yes, dynel is easier to use. It's dearer here than glass and useless for areas likely to suffer any impact but for areas other than decks and hulls, I think it's a really good option. It's much easier to get to adhere to tight curves and to squeeze into corners etc. I think for a cabin top, dynel's probably the best material to use.

Rick

Canoez
10-07-2016, 10:22 AM
Outgassing is a real problem. I never glass in rising temperatures or on surfaces likely to have sunshine on them before the resin sets. But I think the pre-coat system is too laborious and uses too much resin. I find laying glass on horizontal surfaces and spreading with a squeegee or card is really straightforward. As soon as the resin is spread onto the glass, it grips the surface very well. Pools and big bubbles are easily fixed with a little ribbed roller. I haven't tried the foam rollers for glassing - I should, I guess.

I find vertical surfaces more challenging. While it's easier to achieve a nice thin saturating coat on the glass, the top edges can slump. Tape can work but for a hull that I've been procrastinating about for years that I'm going to sheathe soon, I'm going to try plastic staples. They wouldn't suit all situations but the ply hull I'm going to sheathe has 1/2 inch ply that is fairly soft, so I think it should work. The staples don't penetrate far.

Peel ply is really great stuff and well worth the expense. The finish it achieves is very even and a breeze to sand.

Yes, dynel is easier to use. It's dearer here than glass and useless for areas likely to suffer any impact but for areas other than decks and hulls, I think it's a really good option. It's much easier to get to adhere to tight curves and to squeeze into corners etc. I think for a cabin top, dynel's probably the best material to use.

Rick

Rolling on the resin should avoid using too much resin for the pre-coat and it is fairly easy to do.

The thing I'd be worried about is too much excess cloth at the edges causing drips and the cloth to rise up at the edges as it saturates. You'd want a pretty good fit to what you're glassing or to trim as you go.

DeniseO30
10-07-2016, 11:22 AM
After personally glassing the inside of strip 5 canoes I have a bit of experience. the tacky coat is the best way to hold the glass fabric in place as one applies epoxy to fill the weave. A dry roller to press the fabric to the tacky coat under it helps allot too. We only did it when we could spend the time needed all a day and all night if needed.

ron ll
10-07-2016, 12:20 PM
After personally glassing the inside of strip 5 canoes I have a bit of experience. the tacky coat is the best way to hold the glass fabric in place as one applies epoxy to fill the weave. A dry roller to press the fabric to the tacky coat under it helps allot too. We only did it when we could spend the time needed all a day and all night if needed.

Thanks Denise. I can see why the tacky coat would help a lot on the inside of a canoe with a lot of vertical surface. As this surface is mostly flat and horizontal I'm not sure it is that critical but I may try it anyway, a lot depends on the weather and how much time I have for it. I'm convinced of the sealer coat, and the weather will dictate if I let that dry and wash blush, or apply glass while tacky. I'm pretty comfortable with this as I've done it before as well, but it is always good to see how others approach it.

Right now I'm dealing with just discovering this morning that my dinghy motor was stolen last night and the miserable creatures also destroyed the dinghy cover in the process. But compared to what people are dealing with with hurricane Matthew this morning, this is a very minor hiccup.

Yesac13
10-07-2016, 02:57 PM
Some people use composite staples to hold down the fiberglass... The composite staples can be left in with no problems - unlike steel staples that rust. The composite staples also can be sanded off if it happens to be proud.

I glassed an Annapolis Wherry Tandem I built - it uses fiberglass at the bottom and the inside bottom. I put on the cloth dry (plywood not coated) and poured epoxy over it then spread it around with a plastic block (larger than a credit card but similar). It did not move. But that said, this was indoor and you're working outdoor with winds. Another idea is thumb tacks. Stick a few to hold things down then remove as you go over them. By the time half of the fiberglass is wetted out, it should be difficult to move. One other thing that came to mind that I noticed many people use fast hardener. I used slow hardener so nothing really went tacky for at least half hour which helps - when it gets tacky then fiberglass cloth can stick to your hand as you move it away...

Sorry to hear about the outboard motor. I used one of these cylinder style locks over the screw-locking handles. Try getting these in the future or go electric with Torqueedo - very light, easy to take off when not in use. Outboard manfacturers really should include GPS tracking bits somewhere random (change it up time to time) - it doesn't cost much these days...

RFNK
10-07-2016, 08:25 PM
Thanks Denise. I can see why the tacky coat would help a lot on the inside of a canoe with a lot of vertical surface. As this surface is mostly flat and horizontal I'm not sure it is that critical but I may try it anyway, a lot depends on the weather and how much time I have for it. I'm convinced of the sealer coat, and the weather will dictate if I let that dry and wash blush, or apply glass while tacky. I'm pretty comfortable with this as I've done it before as well, but it is always good to see how others approach it.

Right now I'm dealing with just discovering this morning that my dinghy motor was stolen last night and the miserable creatures also destroyed the dinghy cover in the process. But compared to what people are dealing with with hurricane Matthew this morning, this is a very minor hiccup.

Just one tip, if you're intent on using a sealer coat due to outgassing, then I'd suggest letting it dry then sanding it before you glass. If you have an outgassing issue, then you'll still get it with glass on a wet coat. If your only reason to use the wet pre-coat is to stick the glass, then that's a different matter, of course.

By the way, if I was glassing the interior of a canoe, I'm sure I'd use the wet pre-coat and roller approach too.

Rick

bwd
10-07-2016, 10:34 PM
either know your substrate or seal first, then mist with 3M 77 spray glue. A very light coat is sufficient.
Apply cloth dry. Then wet out. This is how you can easily glass things like surfboards with channels in the bottom, sharp strakes, chines etc.
http://www.chemistrysurfboards.com/wp-content/uploads/2015/06/GT3A4401.jpg
1/16 or less radius, you can do 6oz glass this way.
Heavier glass, bigger radius. Naturally you can bend (and break) glass over a convex radius tighter than a concavity you can force it into.
Falling temps and know how much resin your substrate sucks up, or seal the substrate. Common sense.

jsjpd1
10-07-2016, 11:55 PM
The spray adhesive is a great tip.

PeterSibley
10-08-2016, 01:44 AM
As for sealing I have a habit of scraping then rubbing all my left over epoxy into the job as I finish, presealed effectively.

RFNK
10-08-2016, 03:35 AM
The spray adhesive is a great tip.

It certainly is a great tip if the spray glue is compatible with epoxy! I've never heard of this method - it could solve some pretty serious issues in my project.

Rick

RFNK
10-08-2016, 04:00 AM
This is informative:
http://www.boatdesign.net/forums/fiberglass-composite-boat-building/using-3m-super-77-a-42043-2.html

ron ll
10-11-2016, 08:43 PM
I laid the glass cloth today. It went well but certainly is not my favorite part of this whole process. I know this has been a drawn out project but I've been forced to work on it in between rains. But to the original question, I stumbled on a trick that worked well for me. There was a little breeze today so I spread out the cloth on the dry surface and used four old lead spline ducks to hold it down. This allowed me to move the cloth dry until it was relatively smooth. It was then easy to roll the epoxy into the cloth and move the weights as required. Following the advice here I had previously sealed the plywood with epoxy and let it cure. This morning I washed off the blush and lightly sanded it to knock off the zits and to give it a little tooth. Another sunny day tomorrow, I'll again wash blush, sand and add another coat of epoxy to fill the weave a bit. Then it will be ready for trim, paint and reinstallation of hardware.

Thanks all for the pointers, and I hope this thread is useful to others.

Rstafford
10-14-2016, 11:58 AM
Anything Ian says!!