Anyone any thoughts on cutting 6 to 8 mm perpex

Calahonda52

Have access to a load of post covid screens

You tube is full of crap, will need to use a skil saw with a guide, so maybe one with neg angle like for metal

Lumen

I think I've used something like this:

https://www.screwfix.ie/p/freud-f03fs10085-aluminium-plastic-circular-saw-blade-160mm-x-20mm-54t/804vx

because

Rake Angle: 0°

and

https://www.acrylite.co/resources/knowledge-base/article/what-types-of-circular-saw-blades-are-used-for-cutting-acrylic-sheet?category=equipment-materials-and-suppliers

says

Best results are achieved when the teeth have a clearance angle (top clearance) of 10 to 15 degrees. This minimizes contact between the teeth and the material - reducing friction and resulting in less melting. The proper rake or "hook" angle, 0 to 10 degrees positive, ensures the teeth do not strike the material too aggressively. Higher angles can lead to chipping due to poor blade stability and poor control of material feed rates.

The other "multimaterial" blades have much higher rake angles.

Technical stuff aside, when I've cut polycarbonate or acrylic with a hand saw I've used a saw with lots of teeth and sort of "flat" sides, if you know what I mean. Like, you can run your fingers along the side of the saw and it's smooth. That alu/plastic circular saw blade looks a bit like that.

FrancieBrady

https://www.boards.ie/discussion/2058379738/anyone-any-thoughts-on-cutting-6-to-8-mm-perpex

Have cut it with a fine toothed Diablo blade on a track saw, on a sacrificial sheet of insulation. Essential to have it firmly supported as any movement will encourage micro fractures along the edge. I have seen vids of using a blow torch on the edges to smooth the but never had a need to try it.

The Continental Op

If you have plenty then experiment. No point buying a negative angle blade if you find you don't need it?

I've cut small bits on a table saw with an ordinary blade. A mate who is a sign maker I think uses a negative angle blade. I would always tape both sides and because I was cutting small bits cut through some scrap wood above it. If you get the cut surfaces well sanded down with fine sandpaper you can polish the edges with a spinning chunk of round metal like a 13mm socket in an adaptor for a drill.

rob316

Bandsaw is the best job.

I've cut perspex with a track saw and fine tooth blade but found I had to keep stopping as the blade got too hot and you need to move the saw painfully slow to avoid cracking the sheet.

Calahonda52

Thanks to all of you, I have a neg angle saw in the shed, must look at the teeth

FrancieBrady

https://www.boards.ie/discussion/comment/122811484#Comment_122811484

At 6-8mm I haven't had that problem. I use just enough depth on the saw to cut through. Have never done a longer cut than 4ft mind you, heat might be a problem beyond that

Lumen

I also vaguely remember cutting perspex backwards to avoid chipping with a circular saw. Is that a thing?

So many bodges, not enough memory capacity.

Calahonda52

https://www.boards.ie/discussion/comment/122811530#Comment_122811530

Tried that on corrugated sheeting from a screw tube video with a TCT blade, stripped all the teeth off so might work with a HSS blade

The heat build up with the high speed seems to be the issue, might setup outdoors and water cool it

banie01

Its only after dawning on me how useful decommissioned COVID screens would be for building a decent enclosure for my 3D printer🤔

Now to hunt down some "rubbish".

Kimbot

https://www.boards.ie/discussion/comment/122811843#Comment_122811843

depending on your location I may have said rubbish for you ;)

banie01

https://www.boards.ie/discussion/comment/122811910#Comment_122811910

I'm in Limerick, but can certainly drive an hour or so to collect some rubbish ;)

Thanks for the offer btw

meercat

I’ve used a small dewalt battery angle grinder with a thin blade and no issues

monseiur

A Bosch T101A jig saw blade will cut perspex no bother.

GreeBo

Have you tried scoring both sides, supporting and then snapping, like plasterboard?

Dtoffee

I always used a jig saw with fine tooth blade and sellotape on the cut line to avoid splintering….. make sure the perpsex is cramped dowm well as the vibrations will ruin it. Then a quick rub with a sanding block to take the burr off the edges and peel off sellotape = job done.

Calahonda52

Thank for the ideas, ag and js suggestions are tough to get consistent results at scale: I want to make maybe 200 pretty identical pieces

The Continental Op

Would there be any point making a template and cutting out your identical pieces with a router?

CelticRambler

https://www.boards.ie/discussion/comment/122816145#Comment_122816145

200 ??? Are you building a geodesic dome? :D

Whatever the project, that number of (identical) pieces in a "temperamental" material sounds to me like the first genuine justification for buying a desktop laser cutter (of the xTool variety or similar) I've heard of in real life - if the pieces are small enough to fit in the machine. 20€ per piece at RRP (but I'm sure you can find a YouTuber offering a discount … )

Calahonda52

sheets are 1200 by 600 and I expect to be able to recover 2 by 600 by 550 from each so desktop laser not an option

Calahonda52

This is 10 mm, acquired y/day!

GreeBo

I think you should be able to score and snap them pretty easily, since they will naturally want to break across the shorter width anyway.

jippo nolan

a decent straight edge & new Stanley blade, use masking tape to mark cut line on both sides. Cut both sides and snap off supporting the edge.

Calahonda52

Found a Bosch T101A in a bunch of jigsaw blades I bought in Germany in 2011 during a clear out at the weekend.

It was marked plexiglass

At the lowest speed on the jigsaw cuts clean with no melting.

anything above 2 from 5 speed melts

https://www.sealtec.ie/bosch-t101a-special-for-acrylic-jigsaw-blades

Not cheap but a pack will go a long way with care

geographica

https://www.boards.ie/discussion/2058379738/anyone-any-thoughts-on-cutting-6-to-8-mm-perpex

Are you selling any?

Calahonda52

https://www.boards.ie/discussion/comment/122845572#Comment_122845572

Had not considered it, PM me with approx location and what you have in mind

XLR 8

An old long gone friend of mine used to have a strange set up for cutting perspex. The cuts were made from the top flat surface using the lenght of the saw. He had a kind of a jig set up to do it. He was a marine engineer and was always involved in some project or another .