Advice for cutting acrylic sheet

[Hillbilly52]

Hi,

I'm having real problems machining acrylic sheet, i've been routing 3 & 4mm thick A4 acrylic sheet, and am really struggling to hold it down securely, whatever I do the sheet gets pulled up by the bit ( i've been using 3 and 4mm end mills), i've even tried using a vacuum table unsuccesfully. I'm doing shallow cuts less than 1.5 mm and slow feed rates.

Any suggestions would be appreciated as at the moment i'm wasting a lot of acrylic.

Cheers

Alan

[A_Camera]

Double sided tape is the solution but make sure it is removable. Also high spindle rpm so that the cutter is cutting and not digging and pushing forward, pulling the sheet up.

[Chaz]

Look at NYC CNC's superglue vid on Youtube. Im using that for alu and it works well.

[cropwell]

Single flute cutter (preferably an open architecture one), high rpm, compressed air to clear the chips and water spray to keep the cutter cool and stop clagnuts.

Double sided tape is the easiest hold down solution, and if you can cut a pocket in the sacrificial board to fit the acrylic in it stops it moving sideways.

[Toddy]

If i cut acrylic i use a straight single fluted bit,it seems to work well and throw chips out the groove better

[Ger21]

I cut 3mm acrylic with a 1.5mm single flute spiral, using double faced tape.

[magicniner]

I use single flute spiral EM with lots of air for cooling & chip removal, facing cuts give me parts which flame polish (Very carefully) to a good level of transparency.

[Hillbilly52]

Hi,

thanks for all your replies. I think i'll try a single flute cutter with my vacuum table, failing that i'll move on to the double sided tape and if that fails i'll crack out the superglue.

Many thanks for your suggestions, it's appreciated, i'll post how I get on.

Cheers.

[Robin Hewitt]

If you want to cut through acryllic then you want the cheap Chinese K40 laser. A 40W laser converts acrylic to vapour, it simply disappears at an amazing rate of cut. To glue acrylic you need chloroform. I bought a litre from Italy on eBay, it may not be so easy to get once we leave the European free trade thingy so get some while you can.

[A_Camera]

If you want to cut through acryllic then you want the cheap Chinese K40 laser. A 40W laser converts acrylic to vapour, it simply disappears at an amazing rate of cut. To glue acrylic you need chloroform. I bought a litre from Italy on eBay, it may not be so easy to get once we leave the European free trade thingy so get some while you can.

What are you using the chloroform for? Cooling? Isn't that very risky? Or are you using it outdoors? Even so... is it worth the risks?

[Robin Hewitt]

Chloroform dissolves acryllic for that perfect glue line. Everything else is but a poor sustitute.

[cropwell]

To glue acrylic you need chloroform. I bought a litre from Italy on eBay, it may not be so easy to get once we leave the European free trade thingy so get some while you can.

https://uk.rs-online.com/web/p/products/0144399/?grossPrice=Y&cm_mmc=UK-PLA-DS3A-_-google-_-PLA_UK_EN_Adhesives_And_Sealants_And_Tapes-_-Adhesives_And_Glues%7CAcrylic_Adhesives-_-PRODUCT+GROUP&matchtype=&gclid=EAIaIQobChMIy9TC4uHf3AIVwrDtCh135wJUEAQYAyAB EgL05PD_BwE&gclsrc=aw.ds

Methylene chloride can also be used to bond the stuff, but it will mar the surface if you use too much.

[Robin Hewitt]

Chloroform is trichloromethane. :very_drunk:

[cropwell]

Chloroform is trichloromethane. :very_drunk:

and Methylene Chloride is dichloromethane:very_drunk::very_drunk::02.47-tranquillity:

[Robin Hewitt]

...and a cheap cigar is still a smoke!

[magicniner]

...and a cheap cigar is still a smoke!

But I'd rather you than me ;-)

[magicniner]

...and a cheap cigar is still a smoke!

But I'd rather you than me ;-)

[Kitwn]

One fixing method I use for thin wood and acrylic is to firmly clamp the blank down as normal to a sacrificial base and start the cutting with a stand-alone drilling operation to create fixing holes between the parts to be cut. Where possible I also cut holes that are part of the pieces at this point. Fixing screws can then be used at many places within the sheet, not just clamps at the edges. The clamps can them be removed to allow cutting out to the edges of the piece if required.
Depending on what holes are part of the piece to be cut and what extra holes you can tolerate adding, this method can be used to avoid the need for holding tabs.

This works well but needs to be planned carefully and the fixing holes are best drawn on their own layer as part of the overall layout design.