www.ultimatehandyman.co.uk

I was using my tablesaw today to cut a sheet of 4mm acrylic/perspex. Nothing to worry about I thought, seen plenty of YouTube videos doing it this way.

Anyway, cuts done and I'm setting up to cut something else when all of a sudden the blade insert plate comes flying off and lands on the floor on front of the saw. Lucky for me it didn't catch the blade as I would have been in it's path.

Switched the saw off and tried to understand what had just happened ... I mean the insert plate launching itself ????

When I inspected the bade housing I found what looked like a pebble of balled up acrylic. What had happened was the waste from the acrylic sheet had fused together and was probably lodged between the blade and housing. It got caught by the fast moving blade traved up, hit the insert plate and kicked it off.

Never, ever would have expected that. Just shows you, you can never take a tablesaw for granted.

Crikey, you live and learn. I have cut acrylic in the past and have never given it a thought until your post.

DWD

it could only fuse by heat and that wont be on cutting unless the blade is extremely blunt i wonder iff it collected near the blade and friction warmed it up and vibration or other action forced a blob onto the blade ??
but well done for sharing

The blade is a bosch 80 tooth and has only done < 10m of cuts. But I think you are right Al, the 'ribbon' of waste probably fell into the blade housing and whizzed around getting hot.

Thanks for the heads up & glad you're OK.

I've cut quite long lengths of perspex on my table saw without incident. It's an Evolution which has a lower blade speed than most saws - maybe this helped reduce heat build up. I used a fairly new standard Evolution multi material blade.

perhaps ptfe spray or 6/12mm ply on the top clamped on or double sided taped on fully surrounding the blade to fully support the cut and giving you the confidence not to need extra underpant on every cut

https://www.toolstation.com/ptfe-spray/p63929

I have come across melting plastic before fortunately without any incidents, using a jigsaw to cut through twin wall polycarbonate sheeting, had to slow the speed right down to stop it getting soft.

I remember watching a guy cutting or rather trying to cut perspex with a jigsaw. He went all the way through it and when finished it was still in one piece as it had melted and fused behind the blade. Profanity and giggles followed.