Construction techniques for thick clear plastic?

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At a surplus supply store in my area is a stack of a couple hundred plastic cut-offs. They're clear, about 3/8 in thick, 4, 5, or 6" by 18". They're called "plastic" w/out any indication of specific material, but generally they're fairly stiff but not extremely hard.

My question is, what sort of adhesive might allow me to make the "box" (sans the "lid") out of this stuff? I mean, I could use brackets and little bolts to make a box, but presuming I can cut it cleanly, what is a good adhesive for this kind of stuff? Also, let's say that I want to keep the cutting to a minimum.

Does acetone have any potential?

Jay
 
Hi jaylgordon. I am just working from memory but if the clear plastic is "perspex" you may find it difficult to bond them. I dimly recall reading somewhere that chloroform was one of the few products that was effective......But please check that out before investing in any.

EDIT: just done some "Googling". It IS chloroform and it melts the perspex and on joining two pieces leaves an invisible joint apparently.

Again from memory there are techniques for drilling this stuff. The usual wood drill "bits" need to be modified with a file to reduce chiping and fracturing of the material if you drill holes. There are some guys on this forum who do superb work and they will be better able to fill you in on the precise modifications needed. Slow, blunt drill bits are the way to go apparently!!!!

Edit: there is a site with an article on drilling this stuff. try www.mmsonline.com There will be a useful piece in their articles section. "Drilling perspex" in Google will deliver a few useful sites.

I like the idea. Keep us up to speed on your work.

Good luck, Jonathan
 
Thanks for the tips and information.

In my enthusiasm, I didn't even stop to read, er, the print on the paper masking. What I've got are 1/2" thick little sheets of Chemcast (http://www.chemcastacrylics.com/). From the information given, they should be very workable and cementable. A lucky find, except the weird dimensions (well, they are cut-off scraps, not full sheets).

Given the odd dimensions (around 5"x18"), I will probably start by building some narrow "square tube" enclosures for a small tube project. Then, it also seems feasible to use the sheets as the "walls" of an enclosure with different material for base and top.

It's just super-clear stuff, so it's not as cool in some regards as, say, purple tinted 1/2 cast acrylic sheets might be, but for a few dollars a piece, I don't care too much. Plus, they do have nice optical properties-- a little bit of light on one edge sets the opposite edge aglow. So there might be something to play with there, given that I'm building with tubes.

In any "case" (boo!!!), pre-built enclosures are EXPENSIVE.

I will keep this thread updated if at all possible.
 
Ok, I've started to work with this Chemcast stuff, and I need to post pictures. It is VERY easy to work with. I've got a couple parts mounted no problem. It soft enough to drill with conventional bits (slowly-- you can feel the bit cut through), and also soft enough that it doesn't seem to stand any danger of shattering or flaking.

Because it's about 1/2 thick, it'll be necessary to sink holes with Forstner bits for some components mounting.

I highly recommend trying this stuff out. Only thing is that, with the clear stuff at least, you have to want that see-through look.
 
If it's like perspex (acrylic?), you may be able to flame-polish it. File and sand an edge until it's smooth, then run a blowtorch flame over it. (Acetylene torch is good, propane should work) You could try this on a scrap piece.

If you want to hide the innards of the box, frost one side of the panel with something like steel wool, rubbing it in small circles.
 
Some update on workability of this material-- standard drill bits don't work especially well at sizes over 1/8 or so. The leading edge tears into the material too hard. I found that, for countersinking a flat-head screw, e.g., I could prep the hole with (a) a standard drill bit for the pilot hole, and then (b) a masonry bit and a little cone-shaped dremmel (sp?) type bit to grind in a more conical indentation.

I found some pages on working with acrylic, and they recommend grinding the leading edge of your drill bits to dull them and reshaping the point to be more "pointy" (a more acute angle, I guess to be technical)-- but I'd rather just use masonry bits instead of "re-purposing" my good wood bits. I suppose for lots of drilling, though, these tips are worthwhile:

http://www.plasticsmag.com/features.asp?fIssue=Sep/Oct-01
 
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