Good article on thermoforming?

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MillenniumFalsehood
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Good article on thermoforming?

Post by MillenniumFalsehood »

I don't have a vacuforming machine yet. I haven't had a major need for one. Until now.

See, I want to create a clear window for my TIE Defender's new windscreen. I tried cutting the panes individually, which lasted till I go the first one done and realized that I was spending about an hour and a half for a single pane trying to get it cut right.

So I'm going to try this technique called thermoforming. I have a basic idea of how to do it, and I've done it before several times, but I don't know for sure if I'm doing it right. So I'd like to know if more knowledgeable folks than I have written an article on the subject.
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Post by TER-OR »

I've done it, it's tricky. Be prepared to waste a lot of plastic...

Wear heat-resistant gloves, too. Evenly heat the plastic, and pull evenly over the piece - which must be secure.
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Post by naoto »

Have you tried "plunge forming" (aka "heat-n-mash") a go? Used to do that to make canopies and various small plastic parts (e.g. wheel pants, cowl blisters, etc.) for "peanut-scale" (12"~13" wingspan) model aeroplanes. Somewhat crude method but works OK.

http://www.scale-models.co.uk/tutorials ... lding.html
http://paperinside.com/wp-content/tutor ... orming.pdf
http://www.foamflyer.info/canopy.pdf
http://www.ipmsstockholm.org/magazine/2 ... nopies.htm
http://forum.largescaleplanes.com/index ... opic=12319
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Re: Good article on thermoforming?

Post by Tankmodeler »

MillenniumFalsehood wrote:So I'm going to try this technique called thermoforming.
Unfortunately, the raised frames of the TIE fighter's windows aren't going to ever give you good results with thermoforming. The process simply won't handle the fact that the frame is higher than the window pane. You need a master that has a "posititve radius of curvature" everywhere on the form to have a hope of it ever coming out well. You can sand off the frames from the kit part, use it (reinforced) as a master for thermoforming and then add back the frames to the thermoformed windows or you can save yourself a lot of time and can shoot yourself in the head right away, because that's how frustrating it will probably end up being. :)

If'n I was you, I'd either spend the hours per pane or approach one of the casting people here on the site and ask if they will make you a moulding of the original in clear resin. Of course, this won't get you thinner panes.

For that you need a process that draws the plastic into the recesses of the corners of the window frames and for that you need to either push the plastic in (mash form) which will give very inconsistent results for something like the TIE windows, or suck the plastic into the recesses, via a true vacuum forming machine using a proper negative mould with vacuum holes to ensure a good pull.

The only other way to do it is to do what you're doing; cut them out & replace them by hand, one by one, with thinner pieces.

I'm sure the facial tic will celear up after a couple of years...

:)
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