Warped Foam Core and Bad Advice

Automaton25

Grumbler in Training
Joined
Mar 16, 2020
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Location
Colorado
Hello Everyone,

I have a 48"x32" pushpin map that was dry mounted to 1/8" foam core. The company that did this said it would be fine for a pushpin map but it has bowed and is rather flimsy. The company gave me a second piece of foam core with helped but it is still bowed when in the frame. Further reading indicates that this should have been mounted on gator board and that they are not the same thing, despite the company assuring me the foam core would work. Is there any way to fix this? They have ruined a very expensive print.

Cheers,
Andrew
 
Mounting something to the back of foamcore can often fix the warp.
Also, the foamcore could be mounted to Gatorboard.
 
How deep is the frame? Is there room to add more material to the back? It is pretty hard to answer if we don't have all the information
 
How deep is the frame? Is there room to add more material to the back? It is pretty hard to answer if we don't have all the information

There is just over 1/4" in depth. Would a 1/8" piece of gatorboard be enough to keep it flat? What about durability of the foam core, I've read it will deteriorate in a couple years.
 
Hope you have thick skin because you may take a beating on this one. I don't know any framers anywhere that would put a map of this size on 1/8" foam board let alone any foam board. The only way I can see any framer doing this would be due to cost restriction from a client. The framer wants the work and says sure I can mount it for less and this is the outcome.
1/4" foam board, never. 1/4" gator board, absolute minimum. 3/8" gator, better. 1/2" gator, best.
Or you got someone that just did not know what they are doing.
I would adhesive your 1/8" panel to the thickest gator board your frame rabbet will take.
Good luck and hope it works out.
 
Hope you have thick skin because you may take a beating on this one. I don't know any framers anywhere that would put a map of this size on 1/8" foam board let alone any foam board. The only way I can see any framer doing this would be due to cost restriction from a client. The framer wants the work and says sure I can mount it for less and this is the outcome.
1/4" foam board, never. 1/4" gator board, absolute minimum. 3/8" gator, better. 1/2" gator, best.
Or you got someone that just did not know what they are doing.
I would adhesive your 1/8" panel to the thickest gator board your frame rabbet will take.
Good luck and hope it works out.
I was told it would be fine. It's very clearly not have why I'm here.

So your suggestion would be tob how a piece of gatorboard, unfortunately I only have 1/8 to play with. Is that going to be enough to do much? Should I be looking at a different product? Maybe some sort of wood backing/support?

No restrictions were placed on the frame shop and they were told it was a pushpin map prior to any work being done.
 
I suspect they chose foam board because the customer wanted to push pins into it, why it should have been 1/8" thick isn't clear.

Have another sheet of paper as similar as possible to the map mounted in the same way as the map to the back. That could balance out the tension on the opposite sides of the board.

In general whatever you do to one side of a board must be done to the other if it needs to remain flat. This will be true for almost any type of substrate that can flex from tension including gator-foam.
 
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I suspect they chose foam board because the customer wanted to push pins into it, why it should have been 1/8" thick isn't clear.

Have another sheet of paper as similar as possible to the map mounted in the same way as the map to the back. That could balance out the tension on the opposite sides of the board.

In general whatever you do to one side of a board must be done to the other if it needs to remain flat. This will be true for almost any type of substrate that can flex from tension including gator-foam.

Any idea why this wouldn't have been done initially? Just a low quality frame shop? They do restoration will all I figured they would provide quality work. They weren't the cheapest quote either.
 
Foam board, in any thickness, will not hold up well to repeated pin sticks that are near others. It is not very dense, and some versions have so many air bubbles that they will have trouble holding a push pin. Gator is probably a better choice.

But, probably the easy option is to adhere 1/8 inch gator or even another sheet of foam board that has been counter mounted with a similar paper.

Foam board has a certain amount of memory and has a tendency to return to its bowed state if not restrained.

If you are the customer, unless you have moved away, I think you should return to the shop that did the work and ask them to fix it. Most framers will be happy to repair something that isn't performing as expected.

It may be that a less-experienced framer misunderstood the mounting instructions or somebody reached for the wrong material. Presumably, it looked fine leaving the store. I know that I would jump to fix something like that.

I can't speak for others, but I would not charge anything for this even if it cost time and materials. And I would be very upset to learn that a customer was unhappy but did not tell me about it and give me a chance to correct it.

If the map is replaceable at a reasonable cost, it might be best to start fresh rather than try to repair this. It runs the risk of expending more resources without permanently solving the problem.
 
Foam board, in any thickness, will not hold up well to repeated pin sticks that are near others. It is not very dense, and some versions have so many air bubbles that they will have trouble holding a push pin. Gator is probably a better choice.

But, probably the easy option is to adhere 1/8 inch gator or even another sheet of foam board that has been counter mounted with a similar paper.

Foam board has a certain amount of memory and has a tendency to return to its bowed state if not restrained.

If you are the customer, unless you have moved away, I think you should return to the shop that did the work and ask them to fix it. Most framers will be happy to repair something that isn't performing as expected.

It may be that a less-experienced framer misunderstood the mounting instructions or somebody reached for the wrong material. Presumably, it looked fine leaving the store. I know that I would jump to fix something like that.

I can't speak for others, but I would not charge anything for this even if it cost time and materials. And I would be very upset to learn that a customer was unhappy but did not tell me about it and give me a chance to correct it.

If the map is replaceable at a reasonable cost, it might be best to start fresh rather than try to repair this. It runs the risk of expending more resources without permanently solving the problem.

I have taken it back twice now, they cut it to the wrong size the first time. I was told it would flatten when installed in the frame and it did a little. They have new a second piece of identical foam core and doubled it up (without adhesive) and it helped some but it still has a noticeable warp in the frame. It left the shop bowed, they says it was normal.
 
Oh wow. I think I would cut my losses at this point. I think they are too worried about the pennies to see what they are doing to their dollars.

I would at least call another shop and explain the problem. I think if you warn them or make an appointment in advance most of us would be happy to take a look and give you a second opinion.

It is really difficult to be more helpful without actually seeing it.
 
Can you post some pictures? Just to get a general idea and give you some more specific tips.
I don’t know if you have any other framers around who might be willing to take a look and give you options.

I think, just reading this, you would need a deeper frame so it can be mounted onto something more rigid. Maybe wood cross bars might help with the bowing.

It almost sounds like the frame itself might be too tight. So many possibilities, hard to judge without actually seeing it in person.
 
Ylva is right. We need to know more to be helpful. A closeup of one of the back corners, and a shot of the front and back.

I had not thought about cross bracing. There are some other possibilities, too.
 
If you still have room for another 1/8" of FC then you can mount the current piece to 1/8" Luan plywood. That should stiffen it up. You could then use spots of hot glue to glue the plywood to the frame to make it a continuous piece.

You could do this yourself by rolling white glue onto the plywood and weighting the map flat till it dries.
 
Well, that is pretty smart, framah, and likely to work better than any of my suggestions. All the better since it is a user-friendly solution.
 
Doesn't happen often but, every once in a while the brain cells all fire at once.
 
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