Acrylic cutting and carving

Hello

I am new to the cnc router scene, just built my machine and love it. I did a practice run and it came out not bad. But what I really want to do is acrylic carving and cutting. I am totally lost as to what bit or bits to get to use on such a task. Any recommendations or suggestions are totally appreciative.

Well I have a piece of 1/4" acrylic that I am excited to try carving/cut on.

So if I understand correctly, a “STRAIGHT 2 FLUTE BIT” is the bit to use, right? I have a Dewalt611 router, what speed should I set it on?

I was under the impression from youtube video’s and from a FB group I am in that a v carve bit or a diamond drag bit is the way to go.

Best Acrylic cutting bit is single flute up-cut bit, lowest RPM on Dewalt, shallow depth and fast feed rate. I can ruffly say 0.03 to 0.05 depth, 70 ipm. Think about this way. You don’t want to generate heat on cutting surface and you want to leave the cut surface fast. It will start melting otherwise.

1 Like

Is this the correct one?

No must be Single Flute up-cut. It comes with starter kit also.

I’ve been using an 1/8’, one-flute, up-cut at 0.100" DOC, 38 IPM.with the Makita at 3.5 on the speed dial.

just skip to cast acrylic so much easier

cast acrylic ?

If you really want the best results, http://www.toolstoday.com sell cutting tools specifically designed for cutting plastic, acrylics and polycarbonate.

2 Likes

I think he assumed that you were using extruded acrylic, which is what’s available at home stores. That is difficult to machine.

I cut acrylic as a CNC machinist for a plastics manufacturer and a single flute upcut like previously mentioned always gave the best cut. We used Onsrud 65 series carbide single up. I just got some very cheap Onsrud 40 series High Speed Steel versions of the same bit to test. The 1/4" is about $8 compared to $40 for 65 series.

Remember that RPM is your enemy on plastics as it will start to melt. If you can smell the acrylic you are cutting at too high of an RPM. Obviously rigidity of the X carve will limit how fast you can push your tool but if the tool is spinning in the same area for too long it is going to heat up and melt which clogs up the flute and re welds cut material into the cut path.

2 Likes

There are two types of acrylic. Extruded is melted pellets of acrylic that are rolled out between rollers to make a sheet and cast is melted pellets of plastic that are melted into a giant flat mold of sorts to form a sheet.

Cast acrylic has fewer internal stresses and no real grain to the polymers. This allows it to machine with better results and consistancy between the length and width of the sheet. However cast acrylic is about 25% more expensive and is a more specialized product.

ty i just checked them out, i will be shopping very soon

1 Like

Thank you sir, these settings worked perfect on 0.219 thick acrylic sheet for two router bases.

I second @DavidWestley. The Amana bits sold by Tools Today kick A$$. I cut a lot of acrylic and have yet to have an issue.