making nice cuts in styrene etc?

[steveo3002]

im struggling to make neat cuts in thicker stuff , if it takes a few passes with the blade then im not getting a usuable edge and have to sand it flat

any tools i should be using , i have good scalpel blades etc but theyre not man enough to cut in one pass , dremel wheel melts it

just want a neat off the shelf cut

[Skii]

With styrene I tend not to cut all the way through - just score a straight line with a blade and then bend.

[steveo3002]

well yeah ive done that too , but then the snapped edge isnt mint

[E31Shrew]

I used to don some oven gloves and heat up a hacksaw blade

[perdu]

on thick plasticard I slice several cuts down the same line using my steel rule and my favourite Swann Morton craft knife.

And after the first cut or so I reverse the blade so that it cuts a furrow, backwards with the unedged side of the blade. This slices better than trying to cut with the edge because it cuts off spiral "swarfs" (useful for springs too)

I tend to allow a small margin too, and rub the cut off plastic on a sheet of wet'n'dry paper to flatten

To make very straight edges you might like to try holding the blade at a slight angle so the one side is cutting a vertical slot and the other part of the cut is chamfered

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a picture is supposed to tell the story better

isnt' really helping is it

[dr_gn]

I asked a similar question on Britmodeller yesterday: I want consistent cuts of a given angle and length rather than through a specific thickness. Someone recommended the "Chopper II" (put that in Google images if you dare). Basically a guillotine. The problem you'll always have is that a blade stiff enough to cut through a significant thickness of styrene will be fairly thick, and that coupled with the rake of the blade will always give some kind of distortion to the cut face. If you use a razor saw you'll get a rough edge by default.

If it's critical, I'd rough cut it then sandwich it between two steel blocks and sand or plane it to that face. If you need multiple bits, sandwich several together and finish them simultaneously.