I have this curly shaped intake design made out of bent plastic. the plastic is under specifications and the bending is legal, so this design is legal. The problem is I can’t get it to flatten. As you can see, there are a bunch of depressions and I really need to flatten it. so far the bending has been done by hand and with a heat gun or with a heat gun and a metal sort of shell. Anyone have any suggestions?
Find something metal that has the curvature of what you want. Suspend your flat sheet of ABS plastic on top of it with some sort of metal support. (Note how important it is that everything is METAL!!!) Heat up your ABS plastic in an oven so that you can see it soften and the middle of the sheet starts to droop. Quickly pull it out and let the plastic fall or use a vacuum to pull it down or anything like that. The ABS plastic will mold and solidify around whatever metal mold you were using.
Be careful of Robot rule 7
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If the inspectors think the polycarbonate has been melted or cast (the rule used to say molded), they may not allow the intake.
I think if we point out that we only heated (and thus melted) to aid in bending (as per rule 7) we should keep it legal, but we are very aware and cautious to not actually melt or cast it.
we have been flirting with this idea but it seems dangerously close to breaking the rules. We may still do this general thing but push/bend the plastic into the shape instead of letting it droop into the shape.