ajm

Any ideas where I can get:

1) a scoring tool for cutting acrylic (plexiglass)
2) drill bits for drilling acrylic (metal bits are too aggressive)

Screwfix is useless at the moment, the site is always closed due to volume of orders!

I am lead to believe plexiglass will score and break like glass, although you need to score it deeply apparently!

I only need to make straight cuts and drill holes up to 5mm

cheers!

beemerboy

ajm, make yourself a trepanning drill. 5mm holes should be ok using a hss drillbit.
use slow speed to avoid melting.

not sure about cutting. how thick is the stuff. think you can score it, freeze it, then snap it.

you'll have to experiment a bit.

good luck

Dazza

ajm

Thanks BB,

Its 7mm thick and I need a fairly good edge as its being bonded into a box shape.

mj

a jigsaw on slow speed with a metal blade will do it,steady hand required!

as for drilling, I have used wood type drill bits before, the ones that have the little point at the tip.

Scooby-Doo

If you use wood or steel bits with a slow drill speed you will crack or chip the acrylic as the bit will tend to drag in when it takes hold. Use the fastest speed available with very low pressure applied to the drill and take regular breaks when the bit gets warm Make sure the acrylic is firmly supported around the hole to stop any flex occuring. This also applies when using the jigsaw and purchase a blade with as many teeth as possible. Remember if you don't have the original plastic cover on the acrylic the jigsaw will scratch the acrylic to bits as you run it along.

How are you bonding it and if you need advice let me know.

David

If you are in the London area and need it cut and drilled let me know.

Jap2Scrap

Acrylic is a nightmare to be honest. Half the time a normal drill bit will break out leaving something looking like a bullet-hole and it's awful to cut. Can't you use polycarbonate instead? Looks the same, weighs the same but free cuts with a wood saw and drills as easy as pie.

ajm

cheers guys

I am bonding it with a purpose acrylic adhesive. Its not a high load/stress application, its to make a drip tray for a large wet/dry sump filter I am making for an aquarium.

I could use polycarbonate I suppose, its just that I have the acrylic ready to hand (cheaply aquired )

The tray will comprise of a box about 30" x 12" x 3" with the base drilled like a sieve! Water will come in the top via a tank connector and pour out the holes at the base dripping all over the bio media below, so although tolerances won't have to be super precise it will need to be water tight, and I will need to drill probably a couple of hundred holes without cracking the base!

Jap2Scrap

How thick is it? The Acrylic I mean, not the idea

ajm

7mm (as per previous post above! )

Jap2Scrap

D'oh!

Well that's gonna take some doing to be honest. In my previous job something that occasionally came up was making new doors for CNC machines. We used to use polycarb 'cos it's easy to handle but there was an occasion where our buyer bought in Acrylic because it was going cheap. That was 8mm thick, so similar, and we had a nightmare trying to cut it square, in any plane, and drill it for hinges, handles, etc. We tried every saw we had, from chopsaw, woodsaw, jigsaw to handsaws and nothing would cut without clogging. This would force the cut off the straight line and on the lean so it was out in 2 planes! I think we finally rough cut it oversize then machined the edges on the mill running a large end mill on very low speed and feed. Not the sort of thing you'll have knocking around in your garage.

As for drilling the holes, it can be done with an hss steel bit, on very slow speeds, but I wouldn't fancy your chances of doing 200 holes without a f*ck-up. Masking tape over the hole position, both sides, helps but nothing is gonna stop it breaking out if the swarf hangs-up in the drill. Start with a tiny hole (less than 2mm) then do the 5 mm hole. Don't do progressively larger holes up to 5mm as the bit will ****** worse if it's only tring to remove a small amount.

Good luck with it, I seem to remember the buyer getting a right b*ll*cking for getting it for us

ajm

I'm not looking forward to this now!

How about these to drill?

http://www.machinemart.co.uk/product.asp?p=060230212

And for the cutting, rought cut then trim with a router and one of these:

http://www.tooled-up.com/Product.asp?PID=31137

Scooby-Doo

Hi,

If you want to send me a drawing I can give you a quote for the whole thing to be made for you. We also have in stock virtually every thickness acrylic you may wish for and in various different colours.

David

ajm

Thanks, I'll give it a try first and if it goes pear shaped I may be in touch!

The bloke who is building the main tank for me (in acrylic) has also offered to do it, he has a CNC laser saw worth a million quid apparently which gives perfect edges!

The biggest acrylic tank he has done was 40ft!

I have spent too much on this project already so I'll give it a go myself first!!!

Jap2Scrap

Cool as F**k

Just be patient and use a regular hss drill.. those cone things are pants, only any good for rough holes in sheet metal IMO.. A router might be too fast to trim too, clogging is your worry as the acrylic melts into the clearance rake of the cutter..

unclebuck

Is this some cat torturing device?

ajm

Given that it is a filter for my aquarium I should think not.... however, with some lateral thinking, who knows!