Need Help!- Can Bobcad be coaxed into making gcode for a 4 axis hot wire machine?

[seanreit]

Supposed you have two rectangles parallel to each other in bobcad that are parallel in the z plane say 10 inches apart in x. Lets give them 10 inches of Y and offset them in Y by two inches.

Can the gcode be written in such a way that on the left rectangle all Y movements will be written as an A movement and if the Right rectangle is half the size in Y as the left rectangle, all Y movements there will be done at half speed as the A movements on the left rectangle.

It would be very helpful to me if bobcad can write G code in such a way to run a 4 axis hot wire cutter, the current programs out there are not working for me in a way that I can get what I want. I can draw it in bobcad, but have not had any luck figuring out how to write the G code.

[tjones]

What version of Bobcad?

[stab]

I know that this is an old post but I am trying to figure out how to coax BobCad into running my 4 axis hotwire too. I have V23. Any help is appreciated.

[BurrMan]

One of the main things as a start is to be sure to use "contours" as the geometry selected. Do you have a sample file you would like to work with so we have a bases to start?

What do you need to know? Is there a machine make/model and post processor specific here?

[stab]

Thanks for the reply!

Yes I have several .DXF files of simple shapes that I made. I have a Gecko 540 interface. I seems to me that having the ability to create my own machine in BobCam would really simplify things but so far all I can find is adjustments to existing commercially available machines, none even close to my DIY 4 axis hotwire.

Where do I select "contours as geometry"?

[mcphill]

You turn 2D contiguous line geometry in to contours. The command "stitches" each of the line/arc/curve segments in to a single element that can be seleted, and the starting point and direction of cut is identified. You MUST HAVE contiguous geometry for this to work - "perfect" end-to-end connections of each element of the chain.

The "Contour" command is under "Other" in the top menu.

[BurrMan]

Originally Posted by stab Thanks for the reply! I seems to me that having the ability to create my own machine in BobCam would really simplify things but so far all I can find is adjustments to existing commercially available machines, none even close to my DIY 4 axis hotwire. "?

Well we can just start with a base machine and see if we can get code to work on your machine from there. If the DIY is to far off the mark, you may need to contact the post support dept for directions... Can we start with a default "Sodick" and see if the code can work? Please post a simple file and we can start to look at the feature and output from there...

[stab]

BurrMan, thanks again for the help!

This short code was supposed to be a 2"rad arc on one side and 3"rad arc on the other. As you can see I'm using the Sodick AQ325L per your advise. Within BobCad I'm unable to set the machine velocity, whenever I set it it automatically zeros.

also, BobCad uses XYUV and Mach3 uses XYZA, I cant help but think that I'll be running into problems with that. However, BobCad also has the option to use "4axis entities" but I read somewhere that some folks may have problems with that function.

I did get a file from BobCad (similar to the one below) to actually move the X and Y but Z and A did not (I assume it's the XYZA -vs- XYUV issue). There were alot of errors in the code so I just kept deleting lines that Mach didnt like until it would move. I believed it to be EDM functions that Mach didn't understand, i.e. power settings, cooling etc. maybe not though, unsure....

(MACHINE SODICK AQ325L )
(CREATED-MON. 05/31/2010 08:25AM )
TP 0.0000 (ENTER TAPER SIZE HEIGHT)
TN 0.0000 (ENTER TAPER OPPOSITE HEIGHT)
G26 RA0.000 (ENTER PROGRAM ROTATION ANGLE)
N0001 (MAIN PROGRAM)
N0002 G54 G90
N0003 G92 X1.75 Y0.
N0004 G29
N0005 T94
N0006 G01 X2. U1. V0.
N0007 X-2. U-1.
N0008 X2. U1.
N0009 X1.75 U0.
N0010 M02

[BurrMan]

Hey stab,
I would love to dig into this with you, but I've limited experience. If you would create a BobCad bbcd file, with some geometry and a feature added, then we can work from there. I need to start with a "this is what I want", then we can see if we can produce Mach 3 results from that. It would just be easier for me to start this way with something tangible, then we can pass back and forth...."How's this", and "no this other way" until we can get a result or determine we cant.....

Burr

[stab]

Ahh, OK.

to start I'm just trying to make a cone that I can cut into the foam. It will be 1 inch rad on side A/Z (U/V) and 2 inch rad on the other (X/Y). I am able to make this .bbcd file. What I need to do is figure out how to make the file in relation to my machine bed size (width 36"). I figure that I could shoot out 2 lines tangent and 180 degrees out from either side of the cone until it reaches 36". I will then drop a "circle between 2 points" at the end of it and that will be the actual machine movement to produce the cone I mentioned. However, I haven't been able to figure out how to drop those tangent lines.?.?

To simplify things and get BobCad talking to Mach in a langauge that they both understand I'll post a .bbcd file that's symmetrical I'll probably be a square with rounded corners.

This site doesnt seem to be OK with uploading .bbcd files. I haven't actually tried it but I was just looking at the allowable formats and it's not on the list.

Thanks Again!!

[BurrMan]

Stab, Right click your bbcd file and choose "send To-Compressed ZIp folder". This will create a zip file you can attach here...

Yeah, I need to start with a file to be able to get my head around what we are talking about. We'll take a couple baby steps then see if we can progress up.

[BurrMan]

Stab,
Also on the Code configuration note. Have you looked at or tried "Poppabears" 2 and 4 axis screens for Mach3? He specifically worked them to use the xyuv code I think. I can load code and gen toolpath in mach with BobCad wire code.....FYI.