9 replies to this topic

[DEMON]

Well, normal construction materials include pvc, metal and sometimes wood. But what if you made a gun (body, not innerds) out of plexyglass. The idea came to me when I saw this guy's web page. He made a bbmg, looky here: http://swanstrom.net...hoot/autobb.htm

[davidbowie]

Quite a few people have used lexan and plexiglass before, for things like magazine walls and other flat surfaces. It's pretty cool for magazines as you can see how many darts are inside. Outside of that, though, there isn't much advantage to using plexiglass as opposed to, say, PVC sheeting?

What exactly do you mean by making the "body, not innerds" out of plexiglass? I don't think anybody has ever bothered to make a seperate body and put internals inside like Nerf does.

[DEMON]

Sorry, I was thinking of something more like the bbmg. How easy is plexyglass to work with? Can you machiene it easily? I would like to get some, in fact there is a place where I can get scrap peices cheap. I just think it would make a good stock or housing once it is pollished.

[ShadowSniper]

I have a whole bunch of plexiglass I scrounged up. The material is pretty easy to work with as far as cutting, bending, forming go, but be carefull as it like to shatter and break really easily. Especially when thin. My advice is just get some PVC Sheet or maybe High Impact Polystyrene.

[Snazzy Q]

Plexiglass is NOT easy to machine. Another thing to remember is that it seizes on screws and is brittle, meaning that it is very difficult to use self-tapping screws. If you want to use plexiglass, drill slowly to avoid cracking. Also, cyanoacrylate (superglue) is perfect for bonding plexiglass.
A good place to get offcuts of plexi is a sign shop. Sign shops are great for scraps of plastic sheet.

[DEMON]

Plexyglass, (slap self on head), Sorry. I mean that super tough see through plastic.I think it is called poly something. Any way I am going to go to a factory and buy some off cuts sometime this week. I will get back to you guys.

[Snazzy Q]

Polycarbonate. AKA Lexan (trade name)
Great stuff, flexible and easy to work with.

[Zero Talent]

Quite a few people have used lexan and plexiglass before, for things like magazine walls and other flat surfaces. It's pretty cool for magazines as you can see how many darts are inside. Outside of that, though, there isn't much advantage to using plexiglass as opposed to, say, PVC sheeting?

What exactly do you mean by making the "body, not innerds" out of plexiglass? I don't think anybody has ever bothered to make a seperate body and put internals inside like Nerf does.

I have to disagree with the Snazzy one, but I guess "easy" and "hard" to machine are all relative. My opinion however, is that plexiglass is quite easy to machine, though like he said, it can be a fairly brittle material. I've always just treated it like a brittle Aluminum: Deburr with a light file, tap it for any machine screws (though cyanoacrylate won't assist fracture!), but try not to put it under too much tension. It does crack easily, like the liquid tilt capacitor I made 5 months back.

Using solid chunks of polycarbonate is certainly a good way of prototyping, especially for visual display, but I don't know if all our members here really want to have to try and scrounge or buy chunks of it, or have the machining skill to make something that won't eventually crack and leak. Sure, we could all custom machine everything for our blasters out of aluminum, too, but then I fear it would be all too professional. I was always a big fan of the $5 hardware store solution for its ingenious simplicity.

That's a pretty cool BB gun.

Edited by Zero Talent, 22 August 2006 - 12:44 PM.

[CaptainSlug]

"plexiglass" is not a material but a vaguely related set of clear plastics with varying properties.

Acrylic is so-so for machining and is picky about blade types, cutting speeds, and temperatures. It can be an annoying material to work with and requires a good deal of practical experience to machine if you want to avoid spitting, cracking, shattering, and melting. It doesn't hold up under load stresses very well and is too brittle to be used for anything related to nerf outside of valve housings.

Polyester (PETG) is a very very soft plastic and can be weirder to machine than PVC. It cuts so easily that most power tools will burn through it overzealously and therefore it can prove to be a challenging material to work with since it's almost as formable as wax when heated even slightly.

Polycarbonate is an extremely friendly and forgiving material to work with provided you don't get a cheap grade of it and you are working with the thickness suited to your application. it has a higher ceiling temperature of stability compared to other plastics, but proper blades and the application of cutting oil are still advised. Polycarbonate tools very similarly to aluminum under most circumstances and can hold a thread extremely well. It's also extremely durable while still being fairly affordable.

Check your local phone book for plastics shops or sign making shops and called around to a few to ask if they sell their off-cuts. Buying what you need as off-cuts will allow you to buy what you need for a few dollars per pound, which is often times more than 80% off wholesale prices.
Otherwise order from http://www.mcmaster.com or http://www.usplastics.com

[Snazzy Q]

Speaking of plastics, another nice material to work with is polyethylene. Polyethylene is the plastic used to make those nice white cutting boards. It is very easy to work with and is very strong.