Canvas stretch - problem

[kazziu]

Hello.
I started making canvas prints and the first time i have landed a nice job almost immediately i have stumbled upon problems. The order consists of 100+ stretched canvases, size is 27x19 inches. The problem is the canvas material, after a week the canvases loosen and the material is far from tight, unnaceptable for the client. I hammer the pins/pegs in the corners for the finishing stretch and at first the material is so tight i could play a drum solo but after a week it's far from client ready. I use a polyester/pcv canvas material but the same thing occures when a use a more natural canvas material, i print on Latex. Do You have any ideas how can i improve the tightness so it could last?
Thanks.
Kazimierz.

 

[Dan360]

Do you take the canvas around to the back of the frame and staple it? We also use a line of glue on the inside edges before we fold up the frames and assemble.

What brand and thickness of canvas are you using?

 

[kazziu]

Yes we do staple it quite densely, we use Apex Premium Polyester canvas 240g, i try to figure out if its the canvas, our technique or is it the frames, i think it's the canvas but maybe someone has a different proposition?
Thanks.

 

[Dan360]

I would guess it's the canvas. If it's tight when it leaves your shop then it's stretching out over time, I would check to make sure the canvas is actually meant to be used in stretch frames.

The only thing I could think technique-wise is that maybe it's too tight or your corner brackets are slipping out somehow. Are you able to just re-hammer the corner brackets in and get the tightness back?

Maybe a picture of your frames and corners would help.

 

[AF]

Check if the bars are deflecting. Add a spreader if needed. Cotton / Flax canvas tends to stay tighter. Heavier weight canvas will stay tighter.

 

[#racewraps]

I would guess it's the canvas. If it's tight when it leaves your shop then it's stretching out over time, I would check to make sure the canvas is actually meant to be used in stretch frames.

The only thing I could think technique-wise is that maybe it's too tight or your corner brackets are slipping out somehow. Are you able to just re-hammer the corner brackets in and get the tightness back?

Maybe a picture of your frames and corners would help.

I totally agree with this, I'd think it's most likely the canvas. I've purchased a few different types to test out. None of which has become loose or floppy since mounted. Even have one about 9 years old that still looks great, not sure what it was printed on, had someone else do it years ago before I had the ability to do it myself. Might want to try spreader bars as well as someone else suggested.

I really like the Sihl Picasso Satin Canvas 17mil so far. Have some others i'd like to try as well.