Bending plexiglass headlight cover

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trevair
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Bending plexiglass headlight cover

Post by trevair »

Anyone know how to bend plexiglass perspex i bought this new off andover norton but tonight is first time ive offered it up the top the cornerz fit flush but in the middle its the thickness of the persprpex outside water would just seep down the back
May even think of drilling in middle to pull it in but knowing my luck it will crack
Clive603
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Re: Bending plexiglass headlight cover

Post by Clive603 »

Gentle heating does the deed. I've bent perspex with a wide nozzle on my old Black & Decker hot air paint stripper. Low setting I think but probably 20 - 30 years back so memory may be failing. Kept it moving and arranged things so the piece I was bending settled under gravity.

Not sure that I'd care to play with a headlamp cover.

Have you asked Andover Norton if they have any ideas? Or perhaps they will put you in touch with the original supplier.

That said my perspex one fits fine but that came from Nortons after I broke the original glass one. So much older but I'd have expected it to be made off the same former. Can't see any fiscal logic for there ever being more than one former out there.

Clive
trevair
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Re: Bending plexiglass headlight cover

Post by trevair »

thanks clive
will ring norton this morning, still got the original glass one but teres a stone chip in it which autoglass may do something with and a crack at top right hand corner although when the foam is fitted it doesent show so it might be going back on
thanks again for everybody's help on this project
trev
Clive603
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Re: Bending plexiglass headlight cover

Post by Clive603 »

Thinking about this the cover being proud of the seal in the middle indicates that it is slightly over bent.

As you have an original glass cover the bend could be roughly checked against the glass one by laying it against both outside and inside. If the perspex cover is clear of the glass one in the middle when laid on the outside it would pretty much confirm that it is over bent having a slightly too small radius. In theory sufficiently warming the perspex cover whilst it sits on top of the glass cover will let it sag so its inside curve radius matches the outside curve of the glass one. Obviously the radius of the resulting curve will now be a little too large so there will now be gaps at the outside edge rather than the middle when it is offered up to the fairing. If my visualisation is correct the residual gap at the edges should be rather less than the original gap in the middle so the fixing screws will nestle it down nicely onto the seal.

Although I managed to get neat bends by letting heated perspex sag around a curved edge back in the day it was for a simple "half inch (ish)" radius 90° bends between two flats so the working area was much more localised. I suspect it was a third time lucky job too!

A Google search turns up several references and YouTubes to bending perspex which may of may not be useful.

Clive
racecomp
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Re: Bending plexiglass headlight cover

Post by racecomp »

I’ve made lots of plexus and polycarbonate screens.

This is a vacuum formed bubble it makes two screens.
I made this for the works RCW588 after the fire the corner got a tad hot, so I made a new one.
4FF9AE81-C405-4A84-99D7-16760097BC4C.jpeg
Plexus is very tricky, it absorbs water and needs to held at elevated temperature to remove the moisture trapped inside or it will micro bubble and go molly when it becomes soft enough to bend.
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racecomp
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Re: Bending plexiglass headlight cover

Post by racecomp »

racecomp wrote: Thu Jun 09, 2022 12:24 pm I’ve made lots of plexus and polycarbonate screens.

This is a vacuum formed bubble it makes two screens.
I made this for the works RCW588 after the fire the corner got a tad hot, so I made a new one. 4FF9AE81-C405-4A84-99D7-16760097BC4C.jpeg

Plexus is very tricky, it absorbs water and needs to held at elevated temperature to remove the moisture trapped inside or it will micro bubble and go milky when it becomes soft enough to bend.
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