How well does PMMA mill?

[magomago]

I'm kind of curious 🙂 I _may_ have access to a machine shop and I want to mill a simple part using PMMA (really simple - just a block with a triangle cut in the long axis through part of it and . This place doesn't do injection molding or really deal with plastics, so they 99% of the time work with metals.

But I'm curious if PMMA mills well. I'm getting some google results that imply it can be milled (mainly papers that mention it), but I guess anything can be milled...but whether or not it can appear nice and ultimately smooth is the issue 😉 I want PMMA cause its lighter, but I'm sure I could find a place around here to donate 99% Alumimum if that is the only option.

TY 🙂

 

[PlasmaBomb]

They used to make hard PMMA contact lenses using lathes. As it is plastic you can buff and polish it after it has been cut if the finish isn't high enough.

 

[wwswimming]

http://pslc.ws/mactest/pmma.htm

wow. lots of uses, including the windows around hockey rinks.

i got a tour of a contact lens factory in West Marin once. they had a CNC lathe
hidden away among all the fancy restaurants. it machined real well.

opposite end of the spectrum from high nickel content steels, in terms of
machine-ability.

 

[dkozloski]

A woodworking router does a good job if the cutting tools are sharp. If it gets warm evertything goes to the worms.

 

[CycloWizard]

It largely depends on the exact PMMA you're talking about. If the molecular weight is high enough, you can probably machine it without too much trouble. If it's lower, then you'll run into more problems because it will be less stiff and will tend to soften at lower temperatures.

 

[insect9]

I still make PMMA contact lenses on a lathe on an almost daily basis. Works fairly well.