I recently lost two figures to unfortunate plastic warping. I like to work with dyes, and I'm always patient with it - I can get good results if I'm careful. Low heat and constant vigilance while the plastic heats up is key. But two of the figures I recently worked on had some very small pieces which floated in the dye solution. Typically I heat the dye/water/acetone mixture in a pot, on very low heat - gas burner kept on lowest setting - so parts can warm up gradually. The pieces that stay submersed heat evenly and don't warp. Soft plastics take the dye fairly quickly, so I can usually do those pieces in 15 minutes or so. The harder plastics - less porous, I mean - have to sit, sometimes for hours, until they start to take the dye. It's worth it when it works! But this is the first time I've had pieces that float. Normally after stirring the pieces for about an hour I can be sure that they've heated evenly, cover the pot and walk away, checking on it every 30 minutes or so. This last time it didn't work - the first time I checked back the pieces had warped, because they floated. Any suggestions on how to avoid this in the future? Also, related: has anyone had any luck heating warped pieces and getting them to correct the warping? Getting back to their original shape, as it were? Or should I just assume the pieces are trash and toss them in the recycling?