Drilling plexiglass

[Paul W]

Just fitted my side windows and I found that a normal drill bit is fine, try and find a fairly blunt bit as it will cut slower and also take your time. A year ago I cracked one of my headlight covers - using a brand new bit.
Also once you start drilling keep the drill held solid as any movement other than towards the work will crack the plastic. A piece of wood behind the plastic helps and I also just used the weight of my drill as the pressure on the plastic.

[Jim c]

This may help.

A freind advised me to put a champfer on the leading edge of the drill bit, this stops it grabbing & pulling through the sheet.
He works in the plastics ind.
Jim C

[Pantera1889]

What is the trick for getting small light scratches out of Lexan? [img]/ubbthreads/images/graemlins/help.gif[/img]

[Mark Clapp]

I use products from Novus. They have three, No. 1 is a cleaner, No. 2 is a light scratch remover, and No. 3 is a deep scratch remover. Do a Google search for them and I'm sure you will find where to order them. I got some from a local plastics dealer.

[David Morton]

Meguiar’s Mirror Glaze Plastic Cleaner followed by Meguiars Clear Plastic Polish. I think it's available in the USA.

[LloydGT40]

Along the lines of cleaning up plexi. Has anybody thought about using the Protectant clear film on the windows
I was going to use it the headlight and fog light covers. I wonder if there would be too much distortion. It sure would eliminate scatches, lot cheaper and less time consuming to replace

LLoyd

[David Morton]

Hi Ron,
Very fine abrasive system with down to 6000 grit MicroMesh.
Kit includes anti static cleaner and instructions for Polycarbon windows. Sorry, I don't know the price of one of their kits as I was given one by one of the Engineers in BA. Instructions are very specific about never using a circular motion.
Details are :
Aircraft Window Restoral Kit JB6, made by Micro Surface Finishing Products Inc., 1217 West Third St.,Wilton, Iowa 52778 tEL (319)732 3240 Fax 732 3390.

[Kalun D]

Aircraft Spruce sells plexi drill bits in the small sizes you need for this job.

http://www.aircraftspruce.com/catalo...plexidrill.php

[Ryan]

This may be a tad off topic, but how do you bend plexi? For fabbing a head light cover of sort?

I was told use alcohol, light the sheet on fire, bend it as it gets hot and extinguish the flame?

This seemed ridiculous and painful.

Any idea's?

The other option I was told to do was heat it in an oven over a mold of some form and work it to the shape you want it as it cools?


Anyone have some tips on this one?


Thanks gents.

[Neal]

Anti-static spray helps keep the goobers off.

You can bend using a heat gun. The type used to strip paint is very effective.

[Jonathan S]

I have heard of the alcohol trick being used to separate the membrane in safety glass but I think you would end up with scorched Plexiglas using it to bend Plexiglas. On safety glass they score the glass on both sides and then use the burning alcohol to soften the flexible membrane so that the glass will separate.

[Ryan]

Ah ha. Thansk gents. So the alcohol trick reall only workks when cutting safety glass! Thanks. I'll give the heat gun trick a try, gota make some headlight covers. Take it easy now folks.

[Mike Dozier]

Another option is to let a pro make them...ie. Mark Clapp.

MikeD

[Howard Jones]

You can use a hair drier. Warm up whole piece in hot water at 100F-110F. Or put out in the sun on a hot day on top of something dark like the hood of a car. Then make the bends by heating the area to be bent locally with the hair drier. Hold it in place until it cools. You can use a electric fan to cool it.

You will need some CLEAN leather gloves or you will not be able to handle the hot lexan. They need to be clean or you will leave any dirt, grease, etc embedded in the lexan. This may take a helper.

You can then use a piece of pipe of the correct radius as a form to get the curve. Warm it up with the lexan piece to be bent to the same working temp.

If the radius is near the edge, like on a headlight cover, leave additional material beyond the curve to use for leverage. Then trim it after the part is the correct shape.

Work with some scrap first. Not really hard, just one of those things you have to learn by doing. Start with the small parts first, like headlight covers. The big things like the rear engine cover is quite a bit harder and more expensive to screw up. You will need to work up to things that size.

[Ryan]

Those are good tips!

I will have to do some testing. I have only one headlight cover and would like to try making the other. This is good information, gloves, excess for leverage, clean surfaces, and where to use the appropriate amount of heat.

Practice sounds key, a bit of skill too. I would like to make a rear cover of lexan instead of the glass on my rear deck lid. This would take some practice to get right.

Good stuff sir!

Thanks

[TC]

For drilling plexiglass (lexan), I have had a lot of luck with the drill bit shown in the pic, (assumining I uploaded correctly). I call it a step bit, but I am sure that is not the name of this type of bit. This bit is graduated sequentially from small size to next larger increment and is not a twist bit, so it does not grab lexan and crack it like often happens with twist bits. (read: twist bits grab the material much like the action from a threaded bolt).

For those of you who want to step up the size of your hole to accomodate a small o-ring around the screw as recommended by Hershel

"You also need a very small rubber O-ring that will fit under the screw head. This O-ring seals the hole and allows the plexi or lexan to expand or contract without cracking it"

this is the best way I have tried to increase the hole size. I am also looking at small sections of silicone tubing in order to cut small slices and make simple, correctly sized O-rings.

As always, practice on scraps, use 2 felt covered wood pieces under and to the sides of the hole and I like the idea of warming up lexan (sounds like a good idea, but havent tried it yet).

TC

[Crafty]

Here's some more tips on sharpening a drill for plexiglass, also some notes on expansion co-efficients and hole sizes....

Cee Bailey's Aircraft Plastics

And some purpose made drill bits

TAP PlasDrill Bits: TAP Plastics

And tips from their site

http://www.tapplastics.com/uploads/p...%20Plastic.pdf

ebay store that sells the drill bits

eBay Store - plexiglass: acrylic, plexiglass sheet, lexan


And screws (including powdercoated ones) along with rubber nuts can be found at Sport Bike Fairing Bolts from Bikebolts.com..... a package arrived today.