Shopbot to G-Code or DXF

[andrewm]

Is there any way to convert Shopbot code into G-code for other systems or better yet into something like a DXF file that can be imported back into a CAD program.

I have a number of cut files that were all developed in Parts Wizard and now need to be able to share them with some companies that have other systems. We have spent a lot of time tweeking the files to get them to cut right so I would hate to have to redraw them all in my CAD program. Any ideas?

[paco]

Try FC command; you need to select .SBP file type... this "Reverse engineer" SBP file to G-Code or to DXF file type... BUT, this will "convert" the toolpath...
Is this help?!

[Brady Watson]

Andrew,
Depending on the complexity of the toolpath, Yes. I have back-plotted an SBP using Rhino and some preliminary work in WordPad. Using the Replace function (don't use Notepad for this...too slow), replace all of the "M3," with nothing and delete all other commands. From that point you can pull the points into Rhino and plot them. It is a hit or miss method, but it works more times than not. If the toolpath is done in multiple Z-passes, then you should delete all Z values, and all redundant lines of code (IE 1st pass 1/4" deep...next pass .5" deep...There will be several layers of redundant data depending on material depth...Understand?) This takes a bit of concentration, but it can be done.

2D profile files work very well. 3D files are somewhat difficult to do, but not impossible. You will also need to know what cutter was used to run the toolpath, because your resulting plots will be offset by 1/2 the diameter of the cutter.

OK...here we go. A lot of people wished for this...dreamed of this...and generally are stuck how to do it.

Here is a toolpathed vector in PW.

5091.jpg

As described above, delete all M3 commands, J3 commands and MS commands from your SBP file. Also delete Z-commands. This may be a bit tricky if you had multiple Z-depths in your tool stepdown...You should be left with just X and Y data. Add the codes at the beginning and end of the file like shown in this pic. Save the file as a .txt and open up Rhino.

5092.jpg

Under the tools command choose "Read from File"

5093.jpg

Like magic Rhino will read in the points and connect them with a polyline in the order they are drawn. It's kinda neat because it looks animated when it does it.

The resulting geometry
5094.jpg is pretty good...although you can see a deviation at the bottom right where it didn't go where we wanted it to. You can edit this in Rhino. Keep in mind that it is offset from the origninal vector in PartWizard by 1/2 the diameter of the cutter. Therefore you can used the offset command in Rhino to get it back to original size.

Happy backplotting


-Brady

[paco]

Is'nt Brady a GREAT thinker and sharer?! I wish I could find a automotive mechanics friend to solve some of my car problems like that!!! Not that I have much and that I can't solve 'em but it do take me some times to figure...
Thanks Brady!

[Brady Watson]

Just a side note, someone sent me an e-mail stating that it didn't work in Rhino v3. There may be a difference in command names. It works in v2 for this example. I'm sure you can figure out how to get it to work in v3.

You can plot multiple layers or Z stepdowns by adding the ending and begining code where the tool steps down...Like this:


8.676,8.333,-0.375
8.663,8.337,-0.375
8.650,8.339,-0.375
8.637,8.339,-0.375
7.949,8.339,-0.375
Enter
Invert
PolylineThroughPt
!SelAll
Points
7.949,8.339,-0.750
7.941,8.346,-0.750
7.940,8.347,-0.750
7.853,8.409,-0.750
7.807,8.442,-0.750
7.761,8.472,-0.750
7.715,8.502,-0.750
7.668,8.531,-0.750......

It will give you a layered polyline spaced the distance of your Z step-down.

Hope that helps...I'll post a 3D version when I get time.

-Brady

[gerald_d]

Some old threads, using "Vector" and more:
one
two
three

[John A (Unregistered Guest)]

or
four:
http://www.talkshopbot.com/forum/mes...html#POST11483

[andrewm]

Thanks for the ideas. I don't have Rhino but use 3D Studio Max. It doesn't have this function. Is it possible to do it as an ASCII DXF? I have an import for that.

How complex is the DXF format? I could write a simple translater if I had the syntax to create simple polylines. All I need is simple 2D, but I need it accurate. Anyone know the DXF format?

[srwtlc]

Andrew,

If you want, I could backplot them for you with Vector.

Scott

[mikejohn]

Anyone out there a Visual basic man?
I can take a .spb file, use notebook to make .scr file, which opens in AutoCad using the script command.
This can then be saved as .dxf or .dwg or altered at will.
Doing it manually takes time, I think a visual basic routine, with a bit of tweaking, would work.