Perspex question

Tim M · 15 June 2006, 00:22

I want to make a windscreen for the Osprey. What thickness Perspex should I use - is 3mm going to be a: thick enough for the job b: easy to bend to shape with a heat gun.

Also, I have seen windscreens with flexable black U shaped stuff that goes round to cover/protect the edge. What is this called?

Limey Linda · 15 June 2006, 02:20

This is not a simple project. Unless you know exactly what you are doing you will waste a lot of money. First; Perspex is not the ideal material as if it breaks it produces knife sharp edges, like glass. Polycarbonate is a better material but more difficult to form. My suggestion would be to use flat polycarb. or have it done professionaly. Polycarb. is also much stronger than Perspex( acrylic). Hope this helps.

bedajim · 15 June 2006, 07:07

Hi

I used 3 mm polycarbonate; you can get different shades/colours etc

If you want to shape it the best way is to put it in an oven at 2oo C for 2 minutes and then place it over a former and hold it in place until cool (use oven gloves and best done when your wife/mother is out) if it’s no quite as you want it you can warm it again.

Try one of the off cuts first around a wine bottle as all ovens are different

And leave the film on the polycarbonate it may lift a little around the edges but will be fine.

Kernow Buoy · 15 June 2006, 07:48

Tim
look for 'lexan' on ebay, couple of sellers there. 3mm should be fine I bought some 5mm and its too thick to bend easily, 3mm bends really easily even up to 90 degrees with a hot air gun, see if you can have a practice run first though, my demonstrator model is still in my shed!

Tim M · 15 June 2006, 10:26

Ebay is was my intended source; theres a guy selling A3 sheets for £8 and hes local. I'll give 3mm a go

Tim M · 15 June 2006, 10:34

Just bought a sheet - £12.02 with postage. There should be enough for a bit of practice first.

Does anyone know what the black plastic stuff I mentioned before is called?

John Kennett · 15 June 2006, 11:04

Imaginatively enough, it's sometimes known as screen trim!

Motorbike shops sell it, but they might not do the length you need.

John

Tim M · 15 June 2006, 12:03

Quote:

Originally Posted by John Kennett

Imaginatively enough, it's sometimes known as screen trim!

Motorbike shops sell it, but they might not do the length you need.

John

Exellent

daveh · 15 June 2006, 12:32

Tim if you muck it up then give me a ring and I'll get my plastics man to do it for you - he would have done the bending and drilled holes for about the same price!

Tim M · 15 June 2006, 12:34

Thanks Dave. Hopefully the bending shouldn't be toooo hard. I can just about drill a hole my self

BogMonster · 15 June 2006, 12:59

Interesting thread, thanks. I was thinking about doing much the same job myself and wondering how easy/difficult it was

I already have a screen on mine but with mid-winter temperatures not a lot above freezing at the moment, I could do with a bigger one as the wind chill at 30kt gives a bit of a nip in the air

Tim M · 15 June 2006, 13:35

I'll let you know how easy/hard it was once the polycarbinate arrives....

nugent · 15 June 2006, 14:24

cut blank
heat one side at time be patient no rush. i sat an old cloth round a cardboard tube , to pull it round, allow to cool on its own , force cool her it will be brittle on edge. yes even polycarb or lexan goes brittle on tight corners after forming, we work with it all day,
i can allways supply off cuts to fellow rib nobbers in west midlands,
ed

daveh · 15 June 2006, 14:25

Tim

Tape everything both sides before you drill, its very easy to crack!

Tim M · 15 June 2006, 14:27

Whats the best thing to cut it with?

nugent · 15 June 2006, 14:28

nice gentle work with blow torch will give you a nice flame polished edge, which in turn will remove that sharp edge,
mr manning

was miffed and chuffed with my result, dont know if thats good or bad

nugent · 15 June 2006, 14:30

Quote:

Originally Posted by daveh

Tim

Tape everything both sides before you drill, its very easy to crack!

poly carb will be fine it is not like perspex or plexiglass, nice and slow though as it glogs the drill up . circular saw or bandsaw jigsaw etc, jigsawing i recomend you run line of sellotape where cutting as it lubricates the blade whilst cutting through your material

jyasaki · 15 June 2006, 16:32

Edge molding or edge trim. You may be able to find it at auto detailers.

jky

Hightower · 15 June 2006, 20:07

Tim, if you muck it up, PM me. I have a limited supply of Makralon which is a type of Polycarb, we cold form 90 deg bends with a folder and it dosen't break. You can also drill without fear of cracking and is great for screens....Nothing fancy though, just clear stuff available and in 5 or 6mm.

stedj · 15 June 2006, 23:13

tim what size screen are u doing ,i was thinking of having a go at mine, u have a similare console to me . i was thinking of getting a stainless frame made so it could be wider ste dj