getting the best edge on acrylic letters

[greenonionzz]

I am using a Gerber Sabre 4x8 router to make a set of acrylic letters and I am on a quest for the perfect letter edge. Is it unrealistic to think I can pull these suckers of the table with a smoother than smooth edge, or is there additional handwork needed to get that smooth edge? I am looking at making these from 1/2" acrylic.....Any tips/ advice/ tricks?

Please and Thank You

 

[miker]

never used a sabre cut, but on our icut you run multiple depth passes for cutting and then do a finishing pass with a minor offset. follow that up with flame polishing and you should be all set.

that, or purchase a diamond tipped bit and cut it like butter. =)

 

[TyrantDesigner]

Silicon carbide or diamond tip router bit that has a fine tooth to it will give a near smooth edge ... just run through slowly to avoid chipping. Then flame polish for glass like surface.

 

[Mosh]

Sandpaper and a torch....practice first! i can get a "glass" finish, but I f'ed up a few to get to that point.
Although I have never done small letters under 6" and it is mostly small plex blanks that I polish the edges on, but
it works great with some practice.

 

[nwsigns]

There are 2 factors you need to look at.

First is your hold down method, if the part is moving at all then your not going to get a good finish due to the chatter. I have a serious blower and the parts really stick to the table and for small letters I apply transfer tape and cut to that .

Second is your bit and feeds/ speeds - I use an Onsrud Super O, climb mill at 120" per minute at 24000 RPM to get small chips. Thats a 1/4" bit on 3/16" acrylic so adjust as needed.

Done right they come off the table ready to install and almost look like they were done on a laser. I may go through more bits to keep them sharp but its well worth the cost as compares to the time to hand finish edges.

 

[TyrantDesigner]

Sandpaper and a torch....practice first! i can get a "glass" finish, but I f'ed up a few to get to that point.
Although I have never done small letters under 6" and it is mostly small plex blanks that I polish the edges on, but
it works great with some practice.

good call, forgot sandpaper ... you can also drag a sharp knife along the edge too for refining.

 

[weaselboogie]

You could use a polish wheel, but the best would be a flame polish.

 

[digitalwoodshop]

The engraving guys over on Sawmill Creek went in twice buying flame polishers from China. Ones that convert water for a serious small hot flame. I got one in the first buy.

Lots of info posts there in 2 very long threads.

AL