GAK, otherwise know as Scotch Adhesive Putty.
I occasionally use 6" x 6" canvas covered boards for my paintings. They're only about 1/4" thick and quite light, so I had to come up with a way to keep them from moving around while I painted.
When I started using this stuff years ago, GAK was a brand name. Now, I can't find the original GAK, but this SCOTCH Adhesive Putty is basically the same stuff.
You can find this in the office/school supply areas of stores like Target or WalMart as well as in office supply stores like Staples or Office Max. It's usually less than $4 for a package like this one.
This is one of my current works in progress being held firmly in place by Scotch Adhesive Putty.
"Rusty '59"
~a work in progress
6" x 6" x 1/4"
acrylic on canvas board
In this picture, you can see my easel set-up. I use my smaller easels for these small canvases. This one is a standing model but I've also used this idea with my table top easel.
I placed a piece of 2" x 2" wood in the easel's channel along with a 16" x 20" piece of canvas board (1/4" wide) just behind it. The wood raises the small canvas's height so the easel's front lip won't get in my way while I paint. The canvas backed board gives me a solid place to stick the GAK backed small canvas to.
In this photo you can see the old piece of 2" x 2" wood laying in the channel of the small easel that elevates my canvases above the easel's front lip.
You can also see the thin 16" x 20" canvas covered board just behind the wood that provides the solid backing to GAK the small canvases to.
Here you can see how I've stuck 4 clumps of GAK (Scotch adhesive putty) on the corners of the canvas panel.
When the canvas is turned around and pressed gently against the 16" x 20" back panel, the GAK temporarily adheres to the backing, providing a completely stable painting surface for as long as I need it to.
This side view shows the mini canvas temporarily adhered to the stable backing so it will stay still while I paint.
I originally started using GAK instead of tape to hang Christmas cards around the house many years ago.
Then I discovered it was great for holding up my reference photos while I painted.
These days I mostly use my laptop for my reference photos, but I will sometimes print a black and white value image of my reference photo and GAK keeps that paper image in place nicely.
It's completely removable and reusable. It comes off cleanly with no residue left behind.
Thought I'd share this simple, inexpensive idea for keeping our little canvases still while we play with paint.
Happy Painting!