Beveled edge on Acrylic

[Matt McCoy]

Hey gang: I'm looking into shaping the edge of intricate-cut acrylic 1/8" with a slight bevel and I am leaning towards using a buffing wheel.

1) What type of wheel is suggested?

2) What compound would you use?

3) Any other thoughts?

Thanks!

[Kev Williams]

From my experience, with a buffing wheel you'll get a rounded edge rather than 'beveled'. If you can't actually cut the plastic with tool machine (which will bevel-cut by default), would a 1" belt sander work? That, THEN the buffing wheel...

[Matt McCoy]

From my experience, with a buffing wheel you'll get a rounded edge rather than 'beveled'. If you can't actually cut the plastic with tool machine (which will bevel-cut by default), would a 1" belt sander work? That, THEN the buffing wheel...

Hey Kev -- thanks. I can do that. What grit would you recommend?

[Kev Williams]

as fine as you can find, it won't take much to sand the edge, and you want easy-to-buff sanding marks...

In fact, if using a new belt I'd go as far as finding some steel or stainless that you can sand down to wear off the sharp edges of the grit.

And here's an idea for after the initial beveling, if you have an old dead belt- turn it around, and compound the cloth side- That might make a great buffer!
-I've done this with worn out scotchbrite/sandpaper flapper wheels, works great to 'primary' buff, makes final buffing easier!

[Ian Johnson]

You could experiment with cutting the outline, then dropping the table to put the dot out of focus and running the outline again. You could get some alignment issues if you have a cheap chinese laser with a wobbly Z axis, but if you only stop when the Z rods have made full rotations it should be OK.

[Paul Phillips]

Matt, not sure what kind of shape and detail you are shooting for, i think a belt would be too course, you need to go very fine to get a nice polish, i use a CNC or bench mounted router to bevel the edge, then i use a dual action sander down to 600 grit, then buff on a soft wheel with plastic buffing compound for a perfect finish. Tap Plastics sells the wheels and compound but many plastics distributors do also.

[Matt McCoy]

as fine as you can find, it won't take much to sand the edge, and you want easy-to-buff sanding marks...

In fact, if using a new belt I'd go as far as finding some steel or stainless that you can sand down to wear off the sharp edges of the grit.

And here's an idea for after the initial beveling, if you have an old dead belt- turn it around, and compound the cloth side- That might make a great buffer!
-I've done this with worn out scotchbrite/sandpaper flapper wheels, works great to 'primary' buff, makes final buffing easier!

You are the MacGyver of lasers. I'm going to give that a try.

[Matt McCoy]

Matt, not sure what kind of shape and detail you are shooting for, i think a belt would be too course, you need to go very fine to get a nice polish, i use a CNC or bench mounted router to bevel the edge, then i use a dual action sander down to 600 grit, then buff on a soft wheel with plastic buffing compound for a perfect finish. Tap Plastics sells the wheels and compound but many plastics distributors do also.

Thanks Paul -- big help.

[Keith Colson]

This thread gives you a couple of good options for sharp bevels.
http://www.sawmillcreek.org/showthre...egrees-Fixture

Ian's method of defocusing the laser is a really easy way of doing it but can be a little inconsistent with where on the bed you do it. If this works for you then its by far the quickest.

Cheers
Keith

[Clark Pace]

This thread gives you a couple of good options for sharp bevels.
http://www.sawmillcreek.org/showthre...egrees-Fixture

Ian's method of defocusing the laser is a really easy way of doing it but can be a little inconsistent with where on the bed you do it. If this works for you then its by far the quickest.

Cheers
Keith

Another way would be to setup a jig using a router bit with an 1/8 or 1/16 round bevel. But you would not get a gloss finish.

[Braden Todd]

I have a shaper that works well. The edges aren't polished when the piece comes off, but some Novus 4 and a little buffing will clean them up well. Make sure you have a sharp cutter to avoid any deep marks. Or just flame polish the edges after cutting.

Also, if you want to go the sander route id suggest using a glass belt sander. They run through water to prevent your edges from burning/overheating and have tables to set angles. The belts also come as fine as youd like them to, my old 600 grit belt doesn't move much material but after a quick buffing my edges are like a mirror!

Good luck

[Kev Williams]

Hey gang: I'm looking into shaping the edge of intricate-cut acrylic

--I took this to mean Matt's doing something more complex than 3 or 4 straight edges, maybe some round edges, inside corners, etc...
For that reason I didn't mention "beveler", which is by far the best method FOR straight edges!

[Matt McCoy]

--I took this to mean Matt's doing something more complex than 3 or 4 straight edges, maybe some round edges, inside corners, etc...
For that reason I didn't mention "beveler", which is by far the best method FOR straight edges!

That's exactly right Kev. Thanks for the pic.

[Matt McCoy]

I appreciate all the great tips. I'll let you know how they work out.