"Just to provide a place for waste to go?"
yes.
"Just to provide a place for waste to go?"
yes.
When the hole absolutely must be perfect, as in an eye wear display, I use a router. I predrill an 1/8" or so small than route with a template. A forstner with a solid backing will work, doesnt leave as clean an edge.
Take a piece of scrap and try to bend it. Polycarbonate is very soft and you can actually bend it in a sheet metal brake to 90 degrees. Acrylic will shatter as soon as you try the slightest bend. Polycarbonate is also so soft you can take a curl on the edge with a sharp hand plane. Acrylic, you get little chips if anything
You can tap on the edge with something like a hammer, polycarb sounds dull, like it's soft. But that's more of an experience thing. Usually polycarb will have a better protective plastic or maybe paper on it (since it costs more). Often the protective coating will state that it's polycarb. Sometimes the factory edge will be cut with a sheer (something you can't do with plexiglass). Any glass shop should be able to tell you what you have.
Thanks guys.
I will go looking for some suitable polycarbonate so, as the stuff I have is brittle(ish).
I remember seeing perspex in school, would that be suitable alternative to polycarbonate for a crown guard?
Tom
Forstner bits work extremely well in both acrylic and polycarbonate, particularly in a drill press, though they might tend to leave a rough edge on breakout, even when using a clean backer block. This roughness can be easily cleaned up with a countersink or chamfer follower router bit. To avoid this rough edge, begin by drilling a tiny pilot hole though the workpiece; center the Forstner bit on the pilot hole and drill ~halfway through from both sides; this may leave a slight mismatch in bore centers if you're not careful.
"Anything seems possible when you don't know what you're doing."
So I took the 1-1/4" hole saw route. Put plywood above and below, with precut holes in the plywood above to guide the bits (really not necessary - this was in a drill press).
I went very slowly, with slow drill speed, and frequently removing debris (a bunch of which seemed melted, but the holes came out pretty clean).
Perhaps not the best approach, though I'm really not sure. But it did the task, and now I can paint and install the router table door.
- After I ask a stranger if I can pet their dog and they say yes, I like to respond, "I'll keep that in mind" and walk off
- It's above my pay grade. Mongo only pawn in game of life.