Shaping Polystyrene?

[ChevronX]

Shaping Polystyrene?

I am going to start working on my case design again.

And I think I know where I can get enough Polystyrene from.

How would I go about moulding it into the shape I want?

My understanding of Polystyrene is that it flicks off in large chunks. Although I know it is used by people to make moulds etc. I am wondering how can I tame this tameless material?

Thanks alot.

ChevronX

[LostBoyNZ]

I'm creating a case out of polystyrene at the moment and it's actually surprisingly easy to shape, if very messy.

You can cut it with a saw or a knife, but it tends to come off very rough and sometimes in small chunks. I used directions online to make a hot wire http://www.terragenesis.co.uk/infopages/page171.html and that slices through polystyrene like butter. As soon as you turn it off, it's instantly cool too.

Once you've got basic shapes cut, I've been using a handheld sander / grater to shape it, then sand paper to perfect the shape. It works really well, and you don't get any chunks at all.

Remember to wear a mask and such though, as breathing that stuff in is really nasty. You can also get glue especially made for sticking polystyrene to itself or other materials at most hardware stores, it works by very slightly melting some of the polystyrene.

Hopefully some of that helps, my main problem is getting straight lines / cuts.

[crazybillybob]

The trick to getting a straight line in styrene is get a metal straight edge (ruler, yard stick, etc) then use a utility knife to cut the styrene, but don't try an cut through it all at once, make multiple light passes till your through.

You can also cut Styrene with a jig saw or a scroll saw, the best results come from a blade that has a high tooth per inch count (the type used in cutting metals). If your getting flaking an jagged edges, your doing one or more of the following:
Trying to cut too deep (normally utility knife issue)
Your cutting too fast (normally saw issue)
Your blade is too course (saw)
Your blade is dull (all cutting devices)

As for the styrene glue, your average models are made from styrene... So you can use normal model glue to hold things together. As with all plastic glues it causes both pieces to melt a little this forms a strong bond between the two.

It's best to work with Styrene in layers, build one layer of details on another for R2SRV (http://www.thebestcasescenario.com/forum/showthread.php?t=1092) his body has 2 Layers each .02" thick held together with contact cement. This allows impact to flex each layer with out tearing, but allows it to be more ridged overall then a single thick layer can be.


Styrene is also called HIPS (High impact polystyrene) and is a thermoplastic, this means that it's shaped with heat. You can use a heat gun to heat it up and form it into shape or you can go extreme and build a Vacuum table to form parts with it. For some information on Vac tables and the associated items you can check out this site Ralis's Vacuum Form table (http://www.halloweenfear.com/vacuumformintro.html)and read trough this forum thread from Boddaker's UAL 737 build over on Gruntville (http://www.gruntville.com/phpBB2/viewtopic.php?t=15519&postdays=0&postorder=asc&start=80) (some of the pics are missing but the dialog is where the details are!)

Hope this helps you out with you plastic problems!




Your Friendly neighborhood Redneck
CrazyBillyBob

[ChevronX]

Awesome. Many thanks.

[Eclecticos]

You could build yourself a Hot Wire foam cutter.
Here is a guide for building one. Here (http://www.techlib.com/hobby/hotwire_foam_cutter.htm)

http://img227.imageshack.us/img227/675/hotwir5cd1.jpg

There is another guide Here (http://club.cycom.co.uk/hotwire/Hot_wire_cutter_for_polystyrene_foam.html) , Here (http://www.instructables.com/id/Hot-wire-foam-cutter/) <=-

http://img300.imageshack.us/img300/9296/hotwirehc6.jpg

[Eclecticos]

The trick to getting a straight line in styrene is get a metal straight edge (ruler, yard stick, etc) then use a utility knife to cut the styrene, but don't try an cut through it all at once, make multiple light passes till your through.

You can also cut Styrene with a jig saw or a scroll saw, the best results come from a blade that has a high tooth per inch count (the type used in cutting metals). If your getting flaking an jagged edges, your doing one or more of the following:
Trying to cut too deep (normally utility knife issue)
Your cutting too fast (normally saw issue)
Your blade is too course (saw)
Your blade is dull (all cutting devices)

As for the styrene glue, your average models are made from styrene... So you can use normal model glue to hold things together. As with all plastic glues it causes both pieces to melt a little this forms a strong bond between the two.

It's best to work with Styrene in layers, build one layer of details on another for R2SRV (http://www.thebestcasescenario.com/forum/showthread.php?t=1092) his body has 2 Layers each .02" thick held together with contact cement. This allows impact to flex each layer with out tearing, but allows it to be more ridged overall then a single thick layer can be.


Styrene is also called HIPS (High impact polystyrene) and is a thermoplastic, this means that it's shaped with heat. You can use a heat gun to heat it up and form it into shape or you can go extreme and build a Vacuum table to form parts with it. For some information on Vac tables and the associated items you can check out this site Ralis's Vacuum Form table (http://www.halloweenfear.com/vacuumformintro.html)and read trough this forum thread from Boddaker's UAL 737 build over on Gruntville (http://www.gruntville.com/phpBB2/viewtopic.php?t=15519&postdays=0&postorder=asc&start=80) (some of the pics are missing but the dialog is where the details are!)

Lots of good information. +Rep
There is also a Working with Styrene tutorial
in the Tips, Tricks, and Tutorials Section. Here (http://www.thebestcasescenario.com/forum/showthread.php?t=8585)