"Unbending" baseplates?

[jdarlack]

I recently was able to purchase 35lbs of mixed Lego, and included in that haul were the baseplates (and almost the complete inventory) from the Islanders' "Enchanted Island" set (6278/6292).



The raised baseplate (above left) is in near perfect condition, but the other 'flat' baseplate (above right) is bent a bit so that the crease at the bend is slightly discolored (as bent plastic tends to do), and it does not lay flat, but it is not cracked. I noticed that this flat baseplate is of a softer, slightly more 'rubbery' green plastic than my other baseplates or the the raised baseplate that comes with the set.

Does anyone have any suggestions for making a slightly bent baseplate lay flat? I figured that this was likely a common problem with baseplates, and any hints may be helpful to others as well as myself.

[Ye Olde Republic]

You can risk making the pressure crease worse by simply bending it back. That's up to you. However, I believe that this piece has probably been in it's bent position for some time, judging by the age of the set and the fact that it's not just naturally wanting to return to it's flat nature, I'd recommend putting some heavy items on it for some time and let it relax naturally. I little bit of heat from your oven might help too. Bake element, low heat and keep an eye on it!

[Bruce N H]

Mmm, baked baseplates.

[davee123]

little bit of heat from your oven might help too. Bake element, low heat and keep an eye on it!

I recall watching someone boiling LEGO bricks in water which started to deform the bricks? So I'm guessing that it's somewhere in the 150F-200F degree ballpark where you might get the plastic to a point where you can bend it back in place? The temperature that they use in the injection molding process is supposedly about 450F, but that's probably well beyond the melting point of the material.

I think my approach (assuming it's a slight bend) would be to place it flatly between two rigid surfaces (blocks of wood or something) and then raise the heat gradually, until it stays flat on its own.

DaveE

[architect]

All you need to do is run hot tap water over the opposite side of the bend. This will cause the baseplate to flatten.

Ben

[davee123]

All you need to do is run hot tap water over the opposite side of the bend. This will cause the baseplate to flatten.

Huh! I've never tried that before. That's the concave side of the bend or the convex side?

DaveE

[Memsochet]

All you need to do is run hot tap water over the opposite side of the bend. This will cause the baseplate to flatten.

Huh! I've never tried that before. That's the concave side of the bend or the convex side?

DaveE

It would be the convex sides, since that's the side that's bent "outward".

[jdarlack]

All you need to do is run hot tap water over the opposite side of the bend. This will cause the baseplate to flatten.

Cool. We just got a new hot water heater, so I'll be able to get it nice and hot. . . . but not too hot.

[Ye Olde Republic]

Ah-ha!! I knew heat was the answer.

[kor]

Now this is some valuable info here! I often but large misc. lots on ebay and I've always wondered how to fix the warped baseplate. Now I know....