When to sand newly filled canvas...

Howie

Wooden Canoe Maniac
I canvassed & filled an OT HW the other day. Try as I may I can never seem to get a glossy looking finish from the filler. I work for (seemingly) hours smoothing it down by hand (I quit when I no longer have fingerprints and start to bleed) but it just doesn't get as smooth as I think it should be. So I resort to sanding. When do you folks recommend that I start sanding? Too soon and I'll load up the paper too quickly; too late and the filler is too hard & it'll take forever. And sand wet or dry? And if sand-when-wet, then with water or paint thinner?
 
I canvassed & filled an OT HW the other day. Try as I may I can never seem to get a glossy looking finish from the filler. I work for (seemingly) hours smoothing it down by hand (I quit when I no longer have fingerprints and start to bleed) but it just doesn't get as smooth as I think it should be. So I resort to sanding. When do you folks recommend that I start sanding? Too soon and I'll load up the paper too quickly; too late and the filler is too hard & it'll take forever. And sand wet or dry? And if sand-when-wet, then with water or paint thinner?

Howie,

You need to let thje filler dry before you sand it. And you also need to try to avoid burnishing it. If you make it too smooth you will have paint adhesion problems later. There are lot's of posts on this site about both.

Put the boat in the rafters and come back to it in July.
 
A coat or two of oil-based primer (once the filler has cured out) works wonders! You'll sand most of it off but it sands much easier than finish enamel.
 
Stop being a masochist and buy yourself a pair of neoprene coat work gloves (for rubbing in the filler)... You can probably find a pair for less than 10 bucks. :)
 
I've got a bunch of them - and I use them too. First canvas mitts, then rubber gloves, then hands. But the gloves they just don't seem to work as well for me for the final smoothing passes. I think the problem is that you can't sense when they 'load up' with filler between the fingers... so just when you get a section as you like it a big load falls off and you gotta re-do it. That's when I switch to hands.
 
Put the filler on with a paint roller and then use rubber gloves for smoothing/pressing. Put several coats on.
Get it reasonably close and then walk away.
If you have blobs falling off then you have put to much on.
It's supposed to fill, not become a shell over the canvas.
 
Yeah... 2 things:
1) I used a roller to put the stuff on just once - and 2 weeks later I ended up with the worst wrinkles I bet any of you have ever seen. These wrinkles ran in both directions! - left to right & back to front. And I swear that the canvas was very tight before I started. The only thing I can think of that went wrong was that either the roller sucked up too much of the sand, or the cold snap/freezing weather for a few weeks after filling did me in. Either way I'm reluctant to do it again! It was so bad I had to recanvas the damn thing!
2) I remember reading a posting awhile back where the guy moaned that he hadn't paid much attention to the filled surface when he laid it on, but then had a hell of a lot of sanding to do once it hardened to prepare it for painting. So I go to pains to get a nice surface when it's pliable.
 
I use Rollin's filler too... Did you try asking him about it -- the wrinkles I mean? I had one canoe develop wrinkles along the keel line a couple days after filling. It was during hot humid summer weather. A couple days after that they disappeared... I also canvased a canoe in an unheated building during the cold winter months, it took a couple months to dry, and the canvas stayed tight the whole time
 
I have started using a squeegee to smooth the filler. the autobody type of plastic squeegee. It pushes the filler in and smooths it. I brush it on and work it in with the brush then I squeegee a section at a time.
 
Roll it on, rub it in. Go 3 times round the canoe. Lately I let the last coat dry 20 or 30 mins. and go over the canoe again with my palm and it smooths it out nicely.
 
Rollin & I had several conversations about the wrinkles. He insists the canvas wasn't tight enough. He's got the experience... so I guess I'm crazy for not agreeing with him... But I was there and I just don't believe it. I mean, to cause all the wrinkles I had the canvas had to have expanded by, I'd say, 1/4" to 1/2". What would cause that? It's like the mud caused the canvas fibers to relax. And after the wrinkles appeared the cold weather abated a bit, so I moved the canoe to soak up the sun. The heat caused the wrinkles to almost completely disappear - but they reappeared worse than ever a few hours later with the cold/freezing night. I'm still damn puzzled. If you do a search in the Forum on 'wrinkles' I think you can see the pics.

I have to give the squeegee some thought. I've got 2 more to do this summer. Maybe I'll give it a try.
 
I guess I'm crazy for not agreeing with him... But I was there and I just don't believe it. I mean, to cause all the wrinkles I had the canvas had to have expanded by, I'd say, 1/4" to 1/2". What would cause that?

Howie......

Rollin has built a few boats. When he says your canvas was too loose I would not question him...yes you are.
I have used his filler (and rolled it).
Wrinkles don't happen if the canvas is properly stretched. Take ownership of the fact that you did not get it right. Most folks simply have no idea how tight the canvas can be (should be) pulled.

Fitz explained it perfectly. Do what he said. He's done a few (quite a few) boats and I would say he's spot on...
And the squeegee...it makes sense, been meaning to try that some day, but what I do works fine so I probably won't.
 
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