New acrylic project - need lots of help / advice

[Scott Amsler]

I want to make a 3" emblem out of acrylic, but having some problems conceptualizing it all. This would be a 3" round emblem. This is likely to be in 1/8" cast acrylic. I would like to have the CW cut the emblem out, if possible. Then I have questions about the shape manipulation.

Can the CW cut out cast acrylic pieces? How deep? I've read only to go 1/8" deep, but I've seen people talking about using 1/4".
The piece: I want to do a 3" round piece with a raised cross in the middle, and raised letters on top of the cross. So I was thinking about a round emblem about .04". The raised cross would be .08" total thickness, and the raised letters would be full thickness of the cast acrylic.
I have imported the cross image and the text, but I can't manipulate them to work in a step like manner.
Doesn't necessarily apply to THIS project, but if the max depth for acrylic is .1, how do you set the max depth for an imported object?

I might be able to upload an example of a project that I'm working on, if that would help.

[CarverJerry]

Scott, on the acrylic be sure it is "cast" and not extruded acrylic as it will gum up, melt and most likely snap your tool. Same goes with doing lithopanes when using acrylic plastic, only cast acrylic. Corian is another alternative for material. You will have to have someone else help you on the other questions as I'm not the best at that either.

[Nick68]

Hello Scott. I cut through .250 and .500 corian all the time. Set your max cut @ .125... Use a minimum of 4 tabs. Set Tab Height to 1/16. The machine will cut through .500 in one pass using the 1/8 cutting bit, but don't be suprised when the bit breaks or the flex shaft begines to vibrate/chatter.
There are other work arounds like; securing the acrylic to your jig using two sided tape. I use air craft apolstering tape that I got from my brother...He calls it 'sticky snot tape'. You say that you will be using 1/8(.125) stock. In prject desiner, set your board thickness to .135. And set your pattern depth to .135. As the machine carves out the pattern it will also cut it out too. If you are using .250 stock, set the board thickness to .260. You may have to add an extra .010 to these numbers, depends on how True your Z calibration is and wheather your jig base is ridged enough(I use only .750 mdf stock for my jig base along with the 4.5" rule and 2" side rails)...Set your feather at 1/8 or 1/4 so that the carving bit eases down into the acrylic. Set your bit optimization to best and when uploading to your card use either the best or optimum setting. Get a dust collection system. I use the DC-Insert. Even with a dust collection system, from time to time you should clean the Z and Y Idle Pulley Assemble. http://store.carvewright.com/product.php?productid=16175&cat=255&page=2 ...p.s. just cause you can move it with your fingers dosnt mean that it is free of gummy stuff. Learn how to clean this part regularly. Lots of Z and Y issues are atributed to the bearings when the real problem lies with the Idle Pulley.
Using .125(1/8) stock does not leave much room for layored detail(text over a pattern).
Using the add on software http://store.carvewright.com/product.php?productid=21143&cat=252&page=1 will allow you to over lay text.
Carving into corian/cast acrylic can produce some way cool results...there some draw backs too.

Nick68

[Scott Amsler]

58459

Here is an example of the file that I'm working on. It was based on .125" acrylic.

I may bump it up to .25". How do I set a max depth for patterns that I have imported (I have several custom images)?

How do I set up the tabs?

How do I merge the circle and the pattern so it is not carving out all that unnecessary material and straining the bit?

Thank you so much for your help, everyone :)

[Nick68]

You will have to build a rail sled. see attachment.
After writting a thousand word answer, I decided to load some pics and pm you.

[gwhiz]

Even with cast acrylic, you need to be careful with any cutouts. I broke two cutting bits because I set the max depth to deep. Do not cut any deeper than 1/8" at a time...even with cast acrylic you'll melt the plastic and end up with a broken bit. Acrylic is not Corian and you can't treat it the same way.

I haven't had any problem with carving cast acrylic, just with cutting it out.

[chebytrk]

Any recommendations on where to find good (or right type if there is such a thing) cast acrylic? Never tried it before so I want to make sure I get the right stuff.


Even with cast acrylic, you need to be careful with any cutouts. I broke two cutting bits because I set the max depth to deep. Do not cut any deeper than 1/8" at a time...even with cast acrylic you'll melt the plastic and end up with a broken bit. Acrylic is not Corian and you can't treat it the same way.

I haven't had any problem with carving cast acrylic, just with cutting it out.

[Nick68]

Two manufactures links to the meterials that I am some what familiary with. Call them up and they will point you to a second party that is licenced to work with this stuff.
http://www.lghausys.com/
http://www2.dupont.com/Corian_Global_Landing/en_US/index.html