Mounting boards warping

Elliot Burg

Grumbler in Training
I've been displaying 16 x 20 photographs dry-mounted onto rigid boards called Eco Boards from Kool Tack. With that system, the photos are easy to mount and trim. There's no frame, mat or glass--nothing between the viewer and the image. On the back, I've epoxied D-rings, with West Six-10 epoxy, to which I've attached fishing line to hang the photos from picture molding at my show venue.

They look great ... except that the boards/photos have begun to bow slightly from the top. It's not the epoxy, which is highly stable, according to West. Does anyone have any idea as to what the problem may be, and how to fix it?

Eternally grateful,

Elliot Burg
Middlesex, Vermont

Jim Miller

SPFG, Supreme Picture Framing God
Explain more about what you mean by "bow slightly from the top". Can you post pictures?


SPFG, Supreme Picture Framing God
I'd call and talk to Len Lastuck at Frame Specialties about the issue. They are the manufacturer/distributors.


Daniel Smith

True Grumbler
You are putting pressure on the back that is not even. The weight of the mounted image pulls in the direction the image is hanging from.
Probably need to put a stiffener on the back between the hangars to keep the board stiff so it does not bow on you.


True Grumbler
I used Kooltak for photos because of the lower mounting temperature than tissue, and I always placed a 1/2" MDF board on top of the inverted work when I took it out of the press. That eliminated a lot of bowing.

However, I switched to LJ's Mountcore which is a denser foam core. Ideally I would use a Kooltak Mightycore if available,


SGF, Supreme Grumble Framer
A lot of substrates will bow when an image is blockmounted onto the front, even 10mm mediium density fibreboard if given a few years and bit of humidity. I have been told that as the adhesive cures it exerts an inward pull which eventually causes bowing.

One "fix" I have heard of but never tried is to mount something else of similar density like a bit of blank photographic paper on the back to offset the "pull" on the front.


Forum Support Team
Staff member
Mounting a similar material on the back has worked great for larger posters that were not going into a frame. With the information you have provided, I think that might work for this application. But I agree with others that a denser board would help.

And I would call Len about this problem. He is usually glad to discuss how his products are used, and he also listens well to his customers and has developed new products in the past to meet our needs. Not meaning to give him a commercial, but I have found him very receptive and helpful.