Anyone got a suggestions for cutting 6-8mm thick perspex

[SeeO2]

Although not as accurate a multi tool is good for cutting most plastics due to the finer blades , speed control makes it even better imho

Maybe not for 200 pieces though.

 

[TimV]

All the above, plus: (1) in my experience it tends to become more brittle (and prone to cracking) with age, so be particularly careful as this is second-hand. (mind you, the stuff I discovered this on was much older than yours will be). (2) I have successfully profiled it on a milling machine but am not sure whether a router is OK as the cutting speed is faster - I would defer to others on this point, but suspect it's worth a try as long as you watch out for the heat (3) if you have rough edges then very judicious application of a heat gun will remove the sharpness, and make the edge clearer again, but don't overdo it as it will soften- perspex can be heat-formed very nicely. (4) in case you didn't know, you can stick pieces together with acetone.

 

[throbscottle]

The bits of acrylic I've cut have been with a hand saw and it worked very well. Cuts easily enough. I'd go for a hard point panel saw. My power tools are too cheap and basic to chance using for it - I'd probably just get partly melted shards!

 

[ajs]

Whenever I need to do this I use a scroll saw. 90% of the time that's with a 14tpi coping saw blade, moderate speed and the sheet pushed through at it's "natural" rate - that is, the speed where increasing the force applied does not materially increase the cutting speed. I find you don't need to worry unduly about melting, it hacks through the sheet quick enough to be a non issue.

The coping saw blade leaves a nice uniform ridged finish not unlike a milled effect. If that's not what I want I switch to a relatively coarse piercing saw blade which gives a silky smooth finish that needs the bare minimum of polishing to make crystal clear.

Using only hand tools my first stop would be a hacksaw if you can work around the frame. My concern with a panel saw is they're a lot coarser and potentially prone to chipping, although modern Perspex is slightly flexible and a lot tougher than it used to be.

 

[throbscottle]

Hacksaw is too cloggy. Needs courser teeth. 14tpi does it.

 

[johnb80]

There are two varieties of acrylic, cast and extruded. Cast Acrylic is more forgiving and less prone to cracking, extruded acrylic is more accurate but has a lot of inbuilt stresses.

The best way to cut Acrylic is with a laser cutter which doesn't have to cost a fortune and would be worthwhile for a large number of cuts. If you fancy taking a trip to Gainsborough, you can use mine.

 

[meccarroll]

I have a CNC with spindle and the rescommended bit on a CNC for perspex etc is a single flute up cut bit.

"Single flute" so the waste material clears quickly and does not rub against the perspex causing met.

"Up cut" again pulls the waste material out and away quickly helping keep the cut cooler and prolongs the life of the bit.

When you cut down the waste material is pushed down into the cut and can cause heat build up before it is cleared. Not too much of a problem with some materials but perspex needs extra care in this area.

I am not suggesting you buy a CNC to do the job but instead just thought the info might be interesting if you try using a router. You can make a sled for a router in which case the base of the router would not have to travel over the perspex and potentially scratch it. Also most routers have speed control which would be useful.

 

[meccarroll]

There are two varieties of acrylic, cast and extruded. Cast Acrylic is more forgiving and less prone to cracking, extruded acrylic is more accurate but has a lot of inbuilt stresses.

The best way to cut Acrylic is with a laser cutter which doesn't have to cost a fortune and would be worthwhile for a large number of cuts. If you fancy taking a trip to Gainsborough, you can use mine.

That is a generous offer!

 

[Inspector]

You could buy a plastic cutting blade for your table saw or perhaps a track saw. https://bandsawblades.co.uk/product-category/circular-saw-blades/plastic-circular-saw-blades/ They are a triple chip type so maybe a blade for sheet goods would be similar.

A long time ago I cut some up on the table saw for a boat and there was no problems. I can't remember what blade I used but I hand sanded the edges with a sanding block and then went over them with a cabinet scraper. Got the edges very smooth and clean. Now I would probably flame polish them.

Pete

 

[artie]

I had occasion to cut some 5mm perspex like stuff today.

And since I was using off cuts of which I have many I could afford to experiment.

Just used my general purpose wood blade which is far from new and the standard throat plate.

The cut was perfect, better than the photography.

The saw, not that it matters is a Metabo 254m

 

[Sideways]

You might well find that after a couple of dozen cuts, the blade has heated substantially and the cut quality goes to the dogs. Just a caution....