<div class='quotetop'>QUOTE(RacerMachX @ Dec 8 2006, 06:02 AM) [snapback]1373807[/snapback]</div>
When you have the time, could you give more details on how you made the lens?
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The lenses are made by vacuum-forming a piece of 1/8th inch thick acrylic. The vac-forming rig looks like this:
It's essentially just a casting of the eye area of the helmet cut out and built into a fitted box. The box is airtight and has a fitting to connect the shop vac to it (not visible in the picture, it's on the opposite side of the box).
To make a pull from this mold I heat the piece of acrylic in a toaster oven until it becomes flexible enough to form. I still haven't perfected the time and temperature needed to make this work, so I end up wasting a lot of acrylic when it starts to bubble and melt.
Just before the acrylic starts to bubble, I remove it from the oven and drape it over the eye holes in the mold. Then I turn the on the shop vac which pulls the air out from under the lenses and draws the acrylic into the eye holes. This way I have a pair of convex bubble lenses that fit perfectly into the eye holes of the helmet.
Everything about this is dangerous. The acrylic lets off all sorts of nasty chemical gasses when it heats up, it's very hot when it comes out of the oven, and it leaves a smell that guarantees that the oven will be useless for anything else you could want to use it for. In short, don't try this at home.
In other news, I've added the chrome coat using Mirrachrome and it looks pretty okay:
I'm definitely having second thoughts about painting over this. Oh well.