inside glassing
inside glassing
A couple questions about glassing the inside. Is it best to precoat before putting down the cloth? Also how many coats if I precoat. I'm not really worried about a non skid finish but am looking to keep the weight down. If I precoat will it take 3 coats cover all the weave? I am putting down one layer of 6 oz cloth. I am really only looking to have a good solid canoe that I am going use and abuse at times. Once again any opinions are greatly appreciated.
I've only done 2 strip canoes, just glassed the second canoe on the inside 3 days ago.
I used 4oz cloth. I started in the center at the football and worked my way out and up. Takes aliitle more patience than doing the bottom. The only difference in precoating or not is, (in my opinion) without precoating you will have to move alittle slower to give the epoxy time to soak into the wood. By slower I mean "dragging" the brush slower over the cloth to allow the epoxy to flow through the glass plus soak into the wood. I did two "conservative" coats and had a good coating with the non skid finished. (plus I haven't varnished yet) You may see that you may want a third coat with the 6oz cloth.
When I do it again I believe I will do it the same way. (no precoat)
Maybe some of the Veteran Canoe builders will "chime-in".......
I used 4oz cloth. I started in the center at the football and worked my way out and up. Takes aliitle more patience than doing the bottom. The only difference in precoating or not is, (in my opinion) without precoating you will have to move alittle slower to give the epoxy time to soak into the wood. By slower I mean "dragging" the brush slower over the cloth to allow the epoxy to flow through the glass plus soak into the wood. I did two "conservative" coats and had a good coating with the non skid finished. (plus I haven't varnished yet) You may see that you may want a third coat with the 6oz cloth.
When I do it again I believe I will do it the same way. (no precoat)
Maybe some of the Veteran Canoe builders will "chime-in".......
Precoating buys you a bit of time in the glass wetout stage because you don't need to apply as much epoxy. If your epoxy cures quickly, it can help keep things under control. But once you've got the glass on, you'll have used the same amount of epoxy whether you did it in one shot, or precoated first.
How many coats it then takes to fill the weave depends on the type of epoxy you use. I prefer very thin stuff that soaks in easily for the wetout, and thicker epoxy to fill the weave. I've tried many of the System 3 variants, and still like clear coat (thin and slow) for wetout and SB-112 (fast and thick) to fill the weave. It takes only 1 or 2 coats to fill the weave (of 6 oz cloth), but would probably take at least 4 or 5 if I used the clear coat for that. Silvertip would probably take 2 or 3 coats.
How many coats it then takes to fill the weave depends on the type of epoxy you use. I prefer very thin stuff that soaks in easily for the wetout, and thicker epoxy to fill the weave. I've tried many of the System 3 variants, and still like clear coat (thin and slow) for wetout and SB-112 (fast and thick) to fill the weave. It takes only 1 or 2 coats to fill the weave (of 6 oz cloth), but would probably take at least 4 or 5 if I used the clear coat for that. Silvertip would probably take 2 or 3 coats.
Alan
Using west system I skip the precoat and just do the layup as normal and squeegee the excess to ensure the cloth lies tight to the hull. You need to keep an eye on it for bubbles as it will likely outgas for some time afterward. simply use a squeegee to burst them. The fill coat is quick and easy with the squeegee and brush as necessary for the ends. If you stop at this point you can quickly scuff it up for varnish after a few weeks and you are good to go and will have a textured finish. If you want the cloth completely covered like the outside then brush on one coat more.
A word of caution, if you are doing this in really warm weather keep an eye on your times as the epoxy will set up quicker.
A word of caution, if you are doing this in really warm weather keep an eye on your times as the epoxy will set up quicker.
Also have another question. I've got the canoe setting on 2 cradles slung with carpet. do I need to worry about the shape? It seems to change the amount of rocker depending on where they're at. Will it still be as flimsy when the inside is coated? I'm thinking the trim will set the shape but not sure. First canoe and all.
I think if you move your cradles closer together it should help. I just finished the inside of my canoe an hour ago. No precoat for me, I did on the outside but never again. We did 2 full layers of 6 oz on the inside at the same time, simple. I use a 7 inch hotdog roller, an aluminum fiberglass trim roller and1 inch foam brushes for tipping. Even the stems are pretty simple with these tools. Matthew
Well I glassed the inside last night. Didn't go very well. Took some measurements and adjusted the cradles as needed, that part went okay. but I got some wrinkles in the fabric and one spot that set up with the cloth being starved. The wrinkles aren't really wrinkles just high spots where the cloth got pushed up but isn't starved for epoxy. Not sure how to fix that. Not real sure how to fix fix the other spot either. The epoxy set up before i could get soaked into the cloth. I think I got a lot of sanding to do.
Put your center form back in until your ready to glass. I put a strap to hold the hull against the form.
Sand around as much as you can, then take it out and finish sanding at the end.
What happens if you don't, you will stress the glass that you've put on the outside, and this will show in time !
Once you've glassed the inside put a spreader stick across the center shearline. Put a small piece of plastic so the stick does'nt bond to the hull. I'd leave this in until full cure, at least a week.
Precoating is your option. Alan is right on the money !
Good luck
Jim
Sand around as much as you can, then take it out and finish sanding at the end.
What happens if you don't, you will stress the glass that you've put on the outside, and this will show in time !
Once you've glassed the inside put a spreader stick across the center shearline. Put a small piece of plastic so the stick does'nt bond to the hull. I'd leave this in until full cure, at least a week.
Precoating is your option. Alan is right on the money !
Good luck
Jim
Keep your paddle wet and your seat dry!