Where to get custom shaped plastics?

I'm working on the preliminary stages of designing my own case, and ultimately I am thinking of making the case out of a translucent black plastic.
The idea I am working with is using a plastic just translucent enough to let some light through, but not enough to actually see anything through. Then the interior of the case would be lit with cold cathodes or EL. So, without being able to see through the plastic, the result would be that the case would appear to glow a bit, but not enough to be a major distraction. When the computer is off, the case would just look like boring black plastic.
The problem is that I have a strong dislike of sharp, angular edges, want to fabricate the case to be a rounded box with no sharp edges, which just complicates the project. The way I am designing the case, it will pretty much be a box with all edges and corners rounded to a two inch radius. If I just had to worry about edges, it would be relatively easy to get a 4" pipe to use as the main part of a frame to bend the plastic on, but the corners are going to be the hardest part.
Does anyone know where I can have plastics shaped or manufactured to specification?

you can do it yourself, look around a bit for Captain Slugs posts, hes done it/knows hot to. Or just buy plastic hollow tube and make the edges with that

Read my chrome goat project, I've done a lot of writing on bending plastic... sounds a lot like what you are describing. You have to sift through a lot of RL drama and other useless crap though (sorry!). The link is in my signature.

Rounded edges would require either
A) Making a frame out of solid square rod and then running it through a router and a disc sander then adhering all the rails together with solvent
B) beveling and then hollowing out a considerably thick sheet of plastic (very expensive and involves expensive machining).
or
A) Vacuum-forming and heatwarping sheets into the shapes you want

All three require alot of practice working with plastics and a host of tools.

Does anyone know where I can have plastics shaped or manufactured to specification?

Click to expand...

You're looking at a small fortune in labor costs to have a professional do all of the work for you. Also the type of plastic you're desicribing is also not a standard tint and would involve a special order (also expensive). The alternative to special-ordered sheets would be to apply tinting film to the inside of clear sheets to produce the same effect with more control and a much lower material cost.

Why not build it out of acrylic or a similar material then get some tinting like you'd use on car windows and cut it out with a razor blade?

That was what Captain Slug was describing.

That was 20% reflective, 35% transmissive. Autozone has a full range of darkness.

Actually dyed tinted plastic, you don't get much say (opaque or tinted are your usual options), and its fairly expensive.

Rounded edges will be tough. I've never specifically asked, but Frank at clearpc.ca might be able to help you out.


navig

Hmmm... my backup idea has been to just get a v2100 series case and mod the hell out of it. If the custom case goes beyond about $100 more than a v2100, I will just go that route.
A single 48x96 sheet of acrylic would be expensive to have made, and expensive to have shipped to me, but would (hopefully) be enough assuming I don't make too many errors. Most likely, I would buy some clear acrylic to practice on if I do the work myself, which may be the only option depending on how much it costs.
Or I could just go with a v2100, although it will be kind of uncomfortable like the backseat of a volkswagen after I cram a phase change unit in, which is the whole reason behind making a custom case. Using the VapoLS dimensions as my baseline for space required, I would have some pretty interesting space issues to consider with the v2100, but hey, that hasn't stopped me before. Heh, I usually stop about halfway through when I realize how far over my head I really am...

Here's a nice roomy all acrylic case.

It's just the rounded edges that's going to make the project that much more difficult.

DIY vacuum forming....
http://www.halloweenfear.com/vacuumformintro.html

If he's looking for a certain price range then lots of rounded edges are just not going to happen. To make a frame with rounded edges you would need access to a mill and a router.

However, material costs could be reduce significantly by buying your plastic as off-cuts (scrap) from a local plastics shop. You can get everything you need materials wise for dollars per pound.
I would like to point out that you would still need a whole host of tools and the experience using them to accomplish this though.

I had thoughts of a way to do something a bit different that might look pretty good if you did it right. First you'd find some manufactured article that had the shape and curved edges you wanted in the edges and bottom. Maybe something like a 16 inch x 12 inch fish tank. Then you could saw out a ~5 inch strip down the 12 inch sides and round the bottom, and then put it back together again for a normalish case width. You could put it back together with a strip of brushed aluminum round the seam or something, that would look sharp. However, there's probably H shaped channel you can get hold of, that you could actually make the joint with and would look pretty good. If you didn't want the seam in the middle, and were okay with the look still, you could do something like take 1 1/2 inches off the side of your original container thing, and a 4 inch band out the middle, and have two seams, made under a decorative band or with the H channel. Anyhoo, quite a few possibilities for a case that's out of the ordinary there, the hard part is finding a good tote, fishtank or other container to do it with. Ah yes, the back, myself, I'd probably just make it from a regular case back panel...

regards,

Road Warrior

By rounded, it seems everyone is assuming that you mean large radius. As an option to think about...

Get an acrylic(or build it)case. Then sand the sharp edges into a rounded profile(just take the sharp edge off). Polish it up, or for a nice effect frost the WHOLE thing. There ya go. No see thru, and light will still come out.

Yeah, with a "smoked" colored acrylic or something, you could use 10mm thick sheets with a fillet at the corners, and carve the corners round and smooth and polish them vary carefully. Might be able to use flame polishing, which is basically using a blowtorch to melt the surface smooth. Wouldn't look so great on crystal clear acrylic because the joints would be too obvious, but with dark colored stuff, it wouldn't stick out so much.

That bring up a nothing idea. If you want a heavy tint with little or no effort you could simply use a sandwhich of several 1/8" tinted sheets and round the edges ad RoadWarrior just said. This would obviously make the case heavy, but you'd get the heavy tint effect on the sides. And it could easily be done to a stock acrylic case.

The reason why I would want the plastic to be translucent black all the way through instead of just tinted on one side is because I would be sending pieces off to get laser etched. The end result would be that the etched areas would appear to glow brighter than the surrounding plastic, which could result in a very nice effect if done right.
Machining the case would be the hard part, and most expensive for that matter, mostly because the design I am working on has all edges rounded to a five cm radius. The top and bottom won't necessarily have to be translucent, so if worse comes to worst, I could make the rounded corners out of another material. I'm going to have to talk to somebody about this, but I might be able to get two conveniently sized picture frames with rounded corners custom made to my specs, which would probably be the easiest and most cost effective solution...

HEAT , HEAT AND MORE HEAT!!!!....your talking about working with plexi glass, acrylic..blah blah. you need to check out car stereo supplies. try looking for metra fishman products (nice plexi bender/heater) or select products....you can do pretty much anything it takes a little practice but its fun. depending how thick of plexi you use will determine how hard it will be to work with. you can get smoked (black see through) and a bunch of other colors.https://selectproducts.com/html/frame2/frames2.htm hope this helps