Plexiglass & 3D

[Davo]

I've seen great 3d work in plexiglass, is it cut via the same methods as wood?

Such as a roughing pass + finishing?

or is it all just done with 1 detail bit?

http://forum.vectric.com/download/file.php?id=17157&mode=view

[scottp55]

Lot's more info on Vectric site.
http://forum.vectric.com/search.php?keywords=3d+plexi&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search
Also here.
http://www.talkshopbot.com/forum/showthread.php?t=18228&highlight=plexi

[Xray]

I pretty much treat plexi same as wood, exception of course that you must subtract model properties and usually flip [mirror] the subject.

With thicker plexi I do use roughing, some I do not. The one you posted looks like it wouldn't need roughing. I use a .125 tapered ballnose for nearly everything I do, low RPM's to minimize any melting issues.
Plexi 3D can be very challenging but very rewarding when you meet with success. I think .5 plexi is optimum, have used as thick as 1.25" and have used 3/8" at the other extreme, though there is 0 room for error using material that thin.

[Davo]

I noticed your edges are perfect, I seem to run into an issue when I setup the model the finishing pass wants to leave a rough outer edge around the model in the preview, I set it up using a boundary around the model.

Whats the ips you run?

[Davo]

heres the issue its showing with my edges, the bit seems to gouge out the sides no matter what I do, and its not uniform at all.

Pulled the clipart over, did the vector boundary, subtracted, threw the finishing path, this is the result.

http://i59.tinypic.com/123rzbk.png

[bleeth]

Try redoing the artwork with a much higher resolution. Make your model either the same size as the object or only a little bigger.

[Davo]

still the same issue.

Using the vector art 3d models


http://i62.tinypic.com/2zjb5p5.png

[Xray]

Might need to play with the boundary vector offset setting in 3d toolpaths tab for better edge results. There will by defualt always be some edge tearout in 3d models, all you can do is minimize it. Some models are more prone to this than others, increasing resolution as stated can also help. This effect though it is there is not noticed so much in wood or other materials, but is very noticeable with plexi.
I have found that feed speed is not much of a factor in 3d, with all of the z movements it will only go so fast no matter what setting you use, so just put in whatever your max is.

[Brady Watson]

Did you create a 'zero plane' in Aspire? If you don't you'll get ragged edges on any 3D incised or negative model. Put it at the top of the tree above your component.

I second the idea of cleaning up the boundary vector as well. The less nodes you have, the better.

-B

[Davo]

I just tried the zero plane - fixed the issue.

I have never used the zero plane - should I use it all the time?

[Brady Watson]

I just tried the zero plane - fixed the issue.

I have never used the zero plane - should I use it all the time?


No, you only need to add the zero plane when you work in the negative. Positive reliefs do not require this.

-B