Does anyone know if it is possible to hotwire polyurethane foam? Will it produce dangerous vapors? Set on fire? I have a friend who has an odd block of polyurethane foam… wanted to do some hotwiring… thought it would be an easy way to cut a straight line for a stringer. please advise
i am not sure but i wouldn’t try it
You can hotwire EPS because it’s a thermo-plastic material (heat melts it). Polyurethane is a thermo-set material: trying to hot-wire it will not melt it but burn it. And burning polyurethane means cyanurate gas in the atmosphere… Very, very dangerous…
Balsa is right.
Check out this link and use your best judgement.
“That kind of foam- unless it’s heavily fireproofed, I believe emits deadly cyanide gas when burned (a longtime problem with airline cushions). Yes. OSHA burn tests of the same foam found http://hammernews.com/smoky.jpg in the basement of the club produced toulene diisocyanate, acetone, acrylonitrile, - all poisonous or corrosive (to flesh) solvents.”
You could use a jigsaw with a straight edge to cut it in half for the stringer. Or a table saw or band saw if you have access to one big enough.
But if you want to cut the profile you could use one of those cable saws. I’m not sure of the exact name for them, but they are basically a cable with an abrasive coating. You need two people to saw it back and forth. They use them to cut down high branches on trees.
Yes, in the olden days we cut the blanks for the stringer with a hot wire. I did mine in the sanding room streching the wire from one end of the room to the other. Had a mechanism that let the wire slice through at its own rate. Don’t breath the fumes.