Carving 2D line drawings in plexiglass

[TurtleCove]

I've got a bunch of .dxf files of trim moulding, for chair rail, and profiles for going around my doors. 2D. And, I want to cut them into plexiglass, so I have a template.
I've attached an example image of what I'm talking about....not sure if it will come through....

I'm hoping there's a way to import one of these files into Designer, and then have it cut the outline into plexiglass, as a vector (not raster) graphic.

Questions:

If I buy the .dxf Importer, will it allow me to cut the .dxf file as a 2D vector graphic? Do I just select the outside line, and assign a bit to it ?

Which bit should I select?

What about the nooks and crannies around some of the humps, that is typical in mouldings ? The cutting bit won't be able to get into some of those, so am I just out of luck in that regard?

Is it imperative that I buy the .dxf importing software, or can I convert these .dxf files using some other utility, to some sort of vector graphic that Designer can import?

Any help is much appreciated.



61377

[mtylerfl]

Hi,

You can import the DXF vector files via the CarveWright DXF Importer.

If you are simply cutting out the shapes, you would use the standard 1/8" Cutting Bit*. Cutting plexiglass (the cheap stuff) may melt onto the bit and "glob up", so that is not recommended. Cast Acrylic is more suitable for cutting/carving and is OK for the machine.

If the sheet cast acrylic is less than 1/2" in thickness, you will need to use a carrier board jig. I wrote an article about using the Cut Path tool for thin material. It's pretty simple: ISSUE 12 September 2008 – Designer 1.131 New Feature Highlights (http://www.carvewright.com/assets/tips/CarveWrightTips_and_Tricks_Sept08.pdf)

Another approach is to manually assign a bit to an appropriate depth to cut through, with no holding tabs to remove after cutting. This requires figuring out a reliable method of holding down the material so it won't shift during machining. AL (Digitalwoodshop) does this frequently for his Fireman Tags. (search the forum for info...or Al may see this and comment.)

*For the tight nooks and crannies, you can purchase a 1/16" Cutting Bit. Al uses a technique that will slow down the feed/speed of that fragile bit, to reduce the chance of bit breakage. You'll read about that in some of his posts.

[mtylerfl]

Just to add...I am not clear whether you want to cut out the shapes, or just engrave an outline of the shapes onto the plastic.

For "engraving", assign a V-Bit (60 degree or 90 degree) at a shallow depth and it will cut nice, neat outlines into the plastic (again, it 'should' be cast acrylic).

[TurtleCove]

I'll be cutting material about 3/16" thick.
I'll plan on using sheets of cast acrylic, then, instead of plexiglass.

Are you suggesting even cast acrylic may break a 1/16" bit?...I thought that stuff would cut easily.
Can 1/16" bits be bought at my local Sears?
How about some online source, if not?
I assume DXF files are cut as vector graphics...and therefore will cut quickly....true?

In my browsing the web for cast acrylic, I'm finding "Cast acrylic plexiglass". Is that the same thing?

[gwhiz]

Are you suggesting even cast acrylic may break a 1/16" bit?...I thought that stuff would cut easily.

It cuts fine if you go shallow. I'd take three passes to cut 3/16 cast acrylic--there's a max depth spec in the manual, but I can't remember what it is at the moment. Too deep and you'll generate enough heat to melt even cast acrylic--once it melts, you're pretty much guaranteed to break a bit. Don't ask me how I know....;)

Well, OK, this is how I know...

http://forum.carvewright.com/showthread.php?16370-Problems-cutting-carving-Cast-Acrylic&highlight=cutting+cast+acrylic

[mtylerfl]

I'll be cutting material about 3/16" thick.
I'll plan on using sheets of cast acrylic, then, instead of plexiglass.

The CarveWright 1/16" Cutting Bit will be good for that...it is rated to cut through a max. of 1/4"-thick material


Are you suggesting even cast acrylic may break a 1/16" bit?...I thought that stuff would cut easily.

Note that I have not personally tried cutting cast acrylic with the 1/16" Cutting Bit, so...;)
But, I am like you, thinking it should cut through the 3/16" thick sheet of cast acrylic just fine, though. I mentioned Al's technique because he had some bit breakage issues and needed to slow down the feed/speed cutting out hundreds (if not thousands) of Fireman Tags. I don't think you'll have a problem, but there is only one way to find out! (follow the link gwiz provided...lots of good info there)


Can 1/16" bits be bought at my local Sears?
How about some online source, if not?

No, Sears does not carry the 1/16" Cutting Bit, but you can order it directly from CarveWright's Online Store.

http://store.carvewright.com/product.php?productid=18825&cat=291&page=1

There could be be other sources for it, but I don't know of any.


I assume DXF files are cut as vector graphics...and therefore will cut quickly....true?

True, when you have assigned a bit to the vector, of course.


In my browsing the web for cast acrylic, I'm finding "Cast acrylic plexiglass". Is that the same thing?

I believe so. I found this (maybe you've seen this already)...

Why use CAST Acrylic verses EXTRUDED Acrylic ?
• Continuous Service Temp: 180 F (Cast) vs. 160 F (Extruded)
• Formability Temp: 340 F to 380 F (Cast) vs 290 F to 320 F (Extruded)
• Cast acrylic has a higher molecular weight, therefore it will cut, drill and rout cleaner. As you machine cast acrylic, the shavings will flake off whereas the extruded acrylic shavings can gum up on the tool.
• Cast acrylic also offers better glue-joint effectiveness and performs better in laser cutting.

[TurtleCove]

Here's some more info, so maybe you carving pro's have a suggestion....

For these templates I'm cutting out...I can be flexible in the substraight I'm using. I don't have to use an acrylic. But, it does need to 'wear' better than wood. Is Cast Acrylic the cheapest substraight you can think of with these properties?:

Can be cut on the Compucarve, in the 1/8" - 3/16" thickness range.
Doesn't really wear, from handling.
Very stable, and flat.
Quite resistant to moisture.

[spalted]

I'm not sure how you intend to use the templates but would plastic laminate (Formica) work? It's thinner than you were looking for, but has all the other properties.

It routers very well, and you might be able to find scraps somewhere.

I'm not sure how to attach it to a sled though. Liquid hide glue maybe? It might release if you warmed it with a heat gun after cutting. But that's only a theory, unless it works.

[TurtleCove]

I might give that a try.
Double sided tape should work.
Or melted hot glue stick.

[bergerud]

I can only speak for cast acrylic. It is not cheap but it does machine well. Other acrylics (common extruded) melt when any serious machining it attempted. People have carved many different plastics. Anything that routes ok is probably ok with the CW. Test unknown plastics with a router first.

[TurtleCove]

I'm being quoted about $150 for an 8' x 4' sheet of 3/16" Cast Acrylic by a local supplier.
How's that sound?

[Alan Malmstrom]

This place has smaller sheets in all colors for about the same cost per foot: https://www.inventables.com/categories/materials/acrylic