Straightening foam board?
- Thread starter con244
- Start date
I painted foam board quite wet once, and it warped. When I painted the other side, it warped back straight =). So if you got "regular" warping try to carefully apply moist to the opposite side (water makes the paper shrink).
If that does not work, do like wood craftsmen do: look at your piece of material and visualize what could me made of that shape...
If that does not work, do like wood craftsmen do: look at your piece of material and visualize what could me made of that shape...
con244
Senior Member
Ooooh, so the plane is in there I've just got to remove the bits around it 
. The sheets were up against the wall so they may have gotten more exposed on one side than the other. I will try turning them maybe that will even them out. Foam board is quite expensive over here in Australia almost $11 a sheet.
Thanks guys,
Con
. The sheets were up against the wall so they may have gotten more exposed on one side than the other. I will try turning them maybe that will even them out. Foam board is quite expensive over here in Australia almost $11 a sheet.Thanks guys,
Con
If it's nearly trash already . . .
option 1: Several of the models have folded shapes with long edges. If you're careful, you can use the folds to pull the sheet back into shape. align the bow along the long straight folds, with the convex side pointing outward. To make the turn, it'll have to be straight along the fold. watch for warping down the length and alignment of edges beyond he folded areas -- you might have to scrap it anyways.
Also, If you're using Adam's foamboard (Which from your locale you're probably not, but others here do) *any* moisture on untreated paper will cause the sheet to separate from the foam. Here in middle Georgia the humidity alone is enough sometimes.
Which leads to option 2: strip the board. The naked foam is very compliant and will likely flatten on it's own with the paper removed. The stripped foam is about 4-4.5mm, and has about 1/2 the weight. It can be laminated for strength or shape with *WATER BASED* polycrylic (really like minwax's polycrylic , paint on, press & hold flat and give it 6-8hrs to cure), and can be recovered by packing tape, or coated w/ polycrylic and painted.
Now several of the methods in the swappables rely on the paper, so a stripped & tapped board might work for a particular swappable -- might not -- but this is only a *SMALL* subset of plans that can make a sheet of foamboard fly!
option 1: Several of the models have folded shapes with long edges. If you're careful, you can use the folds to pull the sheet back into shape. align the bow along the long straight folds, with the convex side pointing outward. To make the turn, it'll have to be straight along the fold. watch for warping down the length and alignment of edges beyond he folded areas -- you might have to scrap it anyways.
Also, If you're using Adam's foamboard (Which from your locale you're probably not, but others here do) *any* moisture on untreated paper will cause the sheet to separate from the foam. Here in middle Georgia the humidity alone is enough sometimes.
Which leads to option 2: strip the board. The naked foam is very compliant and will likely flatten on it's own with the paper removed. The stripped foam is about 4-4.5mm, and has about 1/2 the weight. It can be laminated for strength or shape with *WATER BASED* polycrylic (really like minwax's polycrylic , paint on, press & hold flat and give it 6-8hrs to cure), and can be recovered by packing tape, or coated w/ polycrylic and painted.
Now several of the methods in the swappables rely on the paper, so a stripped & tapped board might work for a particular swappable -- might not -- but this is only a *SMALL* subset of plans that can make a sheet of foamboard fly!
"Bent" as in something bent them? Are they mangled? Squished? Or are they simply warped?
How bad? Often if you just reverse their position for a day or two, maybe with some weight on them, they will straighten out. How many sheets are we talking? If only a couple, you can always buy new sheets for large pieces like wings, and use the warped ones for pieces that have structure like the fuselage or power pod. Those A and B folds tend to straighten foam out as well.
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rcspaceflight
creator of virtual planes
At least with Dollar Tree foam board, it is the paper that warps, not the foam. I started removing the paper and replacing it with packing tape, it's not as rigid, but can handle more abuse that way.
If you can easily peel off the paper, that might be a way to salvage it. Or re-wet the paper and fold it flat some how. I see other people have better suggestions that I.
If you can easily peel off the paper, that might be a way to salvage it. Or re-wet the paper and fold it flat some how. I see other people have better suggestions that I.
con244
Senior Member
Thanks for your suggestions Dan and others. Don't know what brand this foam board is. I do know that removing the paper is a nightmare and generally leaves the foam in very poor condition. I did turn the board around over night and it has straightened some. I think the moisture in the air on one side and nothing on the wall side of the board may have caused the problem so I've just got to remember that the board has to be exposed to the air evenly before a build. I always paint the finished model so it is not a problem after the build.
Con
Con
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Charlie123
Junior Member
I have the same problem, but how do I straighten the foam board that's already put together in a build like the FT nutball/flyer? Anyone got some ideas? Thanks.
aiidanwings
Senior Member
Just flip it over for a couple of days. It will straighten on it's own. Mild warping of the board will not cause any real problems for most parts because most of the building techniques force the board flat.
I can concur with the method of using hot something. For our foamboard here in Australia, I used a handheld steam cleaner gun, such as the one sold in Kmart. Definitely test on a scrap piece first so you can experiment and fine tune your method. Hope this helps.
Pieliker96
Elite member
The main thing is to not store it vertically if possible, this prevents a good bit of the warping.
To de-warp the foam and keep it that way, I put them so the warping directions counteract (like )()()()()()( ) on my bedroom floor. My laser cutter's base is a solid 3/4" sheet of MDF, which I use to apply even pressure onto the top sheet. Anything reasonably flat and heavy will do.
To de-warp the foam and keep it that way, I put them so the warping directions counteract (like )()()()()()( ) on my bedroom floor. My laser cutter's base is a solid 3/4" sheet of MDF, which I use to apply even pressure onto the top sheet. Anything reasonably flat and heavy will do.
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