Tool marks in acrylic

[andyb]

What is the best way to eliminate tool marks in acrylic besides decreasing the stepover? I have a customer that I cut a logo in acrylic for and they want me to eliminate the tool marks. What would be the best bit to use? The logo is about 14" in diameter. I'm also thinking about using a 1/16" ballnose for the final pass but the cut time will be several hours.

Any suggestions would be appreciated.

Andy B.

[Brady Watson]

Is this a 3D relief? If so, tooling geometry matters, as does cooling the bit. A cold gun, compressed air or rubbing alky will help.

If this is a 2D cut out, you can't totally eliminate it, but you can reduce it by using the right bit as well as make sure that your machine is tight with fresh pinions and reduce abrupt moves by lowering your VR slow corner speed down to 35 or 40.

-B

[andyb]

Thanks Brady.

[khaos]

You can polish the acrylic. I believe that NORVA plastics (http://www.norvaplastics.com/)has what you need to do it. I the clarity they get on the parts makes it look like ice.

I thought that I used a quick pass with propane torch to get a clearer look I dont remember if it was plexy, duralar, or acrylic now. :confused:

[Brady Watson]

Flame polishing is tricky for those who don't do it often, or those who need to polish colored acrylic. I like to use a 6" buffer and Novus 3-step Polish (http://www.novuspolish.com/). You'll sand and then wet sand the edges before buffing with the 3-step. It is easy, forgiving and gives great results.

-B

[bleeth]

You can also bring it to a fine polish with wet sandpaper. If you have ever done this and found it was long and tedious, next time use oil instead of water. What kind of oil? 10w-30!