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View Full Version : how too bend,form,cut lexan/plexiglass


TamiyaCowboy
2nd March 2006, 14:59
Vac Forming

this requires heating your sheet too around 260/280c depending on thickness for it too become rubberised. you can read and make your own Vac former at this link http://members.aol.com/GCGassaway/vacuform.htm

bending lexan/plexiglass is rather simple affair

To curve either of these two products
one must invest in a simple homeowners propane torch kit (generally around
$12.00 US). To bend lexan and plexiglass your piece should be clamped
firmly to a strong, stable surface that is preferably indoors. Once you
have clamped the piece begin to heat the panel along the line where you
intend to have it bend. DON'T put the torch too close for too long as it
will cause the plastics to get cloudy or even bubble up. You will know when
the plastic is ready to bend simply by applying pressure to the free end of
your work piece. Large pieces will require the help of a partner who can
apply even pressure along the entire length of the bend while you torch the
plastic keeping a uniform and consistant source of heat applied until you
have achieved the bend or shape your desire.These types of plastics are
also virtually indistructible but they are also a bit more costly. Wall
thicknesses on these products can go up to several inches thick. remember you need too be careful working with HOT and nearly MOLTEN plastics. please get adult supervision if at a young age.

Cutting lexan

Cutting / Drilling:
Tin Snips (Nice clean cuts). depending on thickness!!
Hack saw (don't cut too fast, or the plastic will melt).
"Utility" (or Hobby) Knife and a metal edged ruler.
Do NOT use a scroll saw due to small blade (it typically 'melts' it's way through the plastic). and can cause problems
Can be drilled (best if drilled by hand). i found hand drilling lexan more easy than hispeed drills these too also tend too melt through the plastic and not cut it. Shaping:
Heat.(Softens at about 290-340F or 143-171C)
Use a strip heater (or use a stove element with two heavy tiles to form a thin strip of heat, or your toaster). or heat torch,oven. remember hot plasics need careful hadling with heat proof gloves when i bend lexan. i will warm up the sheet. But the pipe or whatever you use must be clean. the lexan/plexi will take on any slight imperfection on the item used too form the bend. so be sure too use a item that will be use for bending your plastic only and nothing else.

glass is a almost perfect surface for forming over, bowls work well but will need to be thick glass too widthstand the vacum formed when forming in plastic, steel etc etc its a trail and error thing

hope this helps you guys with the crazy ideas for rigs


TC

lbreevesii
2nd March 2006, 18:05
acrylic is much the same.

fyi: there are special drill bits for plastics like plexi and acryl, the tips are ground differently so that they cut into the plastic rather than grind against it. Helps prevent overheating and the like.

For doing cuts in acryl to form shapes a nice fast way of getting it done is to whip out the ole' dremel and a cut off wheel. Use that to make your rough cut and sand from there to get the shape you want, as well as getting rid of any melted or hazed plastic left from dremeling.

fivecheebs
3rd March 2006, 08:44
Ive just got around to reading that link. Thats very cool, but its only for the dedicated. Lots of work to do for each piece of work you form.

Great resource though, It would be good for knocking out radiator shrouds, fan adapters, maybe even acrylic optical pods inspired by BadAssumption.

TamiyaCowboy
3rd March 2006, 11:16
yes cheebs you do realy have to be dedicated but

once you have you former up and running your fit too mould anything if size allows.

i also notice alot of guys using jars as a res for the cooling systems. i found up an old 125cl alloy spray gun jar (fullsize) so have my res sorted out. i will get my good friend greg too pull me a few testers first.

i also need too add:

when pulling / vac forming the plastic is stretched, so if you use a 4mm thick lexan/plexiglass your looking at a 2mm maybe even 3mm loss

TC