CNC cutting fuses

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crash_out
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CNC cutting fuses

Post by crash_out »

I finally got my CNC machine together. Wings are no problem.

I'm wanting to move on and do fuse peices, and am having a lot of trouble. I started off drawing out the profiles for bulkheads in TCad 14. Wasn't hard, even though I've never used CAD before in my life.

I've tried to use both Profscan and Cadworks with little to no success to convert the images to DAT. I've had more success saving the images as DXF's and importing them directly to GMFC. Sometimes only part of the image will translate. In any event, if I can get the entire image to get in there, I have to use the radial alignment command to equal out the number of steps. This usually adds several cut lines to the image, and none seem to line up properly. The problem is the lines really screw up the part taper, and throws the tower movements outside my allowable range.

Any help would be appreciated, I'm stuck.
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o1moregil
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Post by o1moregil »

I use cadworks, what I do is I import the dxf drawing into cadworks and then manualy trace over it using the drawing tool in cadworks, then I delete the dxf drawing , that leaves the drawing that I just made, then It can be cleanly converted to a dat file, its a pita because you are drawing it twice.

trying to convert a dxf drawing directly into a dat leaves some nasty lines in cadworks,
hopefully Dave fixes or makes a dfx to dat converter that works, the converters that Iv tried havent work. Let see some pics of your CNC
ptsullivan
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Post by ptsullivan »

I have had luck copy out the curves you want to cut into an new cad file and
then joining them into a single closed curve. Then I save it as a .dxf
and GMFC reads it in nicely. I am using GMFC Pro 3.0

-Pete
crash_out
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Post by crash_out »

Here's a few. A few more are in my folder in the gallery.

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Image
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crash_out
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Post by crash_out »

I guess the big killer question is how do you equal out the njumber of steps so GMFC will accept it? I can get images to transfer to DAT. One being a simple half circle, and the other being different, does Cadworks automatically even out the number of points and align them properly? I can get the DAT files into the software, but when I try to use radial alignment to equal points, it goes all crazy.

Here's what I'm basically trying to cut...
Image
Image
ptsullivan
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Post by ptsullivan »

The 3.0 pro version has this feature. It allows you to sequentially pair points from "root" to "tip" and
then it equalizes the number of points in between.
It can be a bit fiddlely but most of the time it works out reasonably.
I think you can try 3.0 pro for free to see if it works, you just can't cut.
THend
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Post by THend »

Use 3.0, cut to file.

Open file.

Strip out data points for new .dat file.

Try new .dat file on older version of GMFC...

Might work..[;)]
crash_out
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Post by crash_out »

I'm using the latest version, 3.0.85 pro.

I tried to watch the tutorials on Gilles site, but for some reason they don't open...
THend
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Post by THend »

Geez.... he has the pro version!!
crash_out
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Post by crash_out »

I played with the software some more, and followed the help file on how to set the zero point and try to align segments...I think the big problem is the drawings I am using have an insane amount of points...The front firewall part is fine-only has about 30 or so points....the rear campopy section has about 1400...I have no idea how to eliminate. I've redrawn the image everyway I know how and it still comes up with well over 1000 points.
ptsullivan
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Post by ptsullivan »

Yeah, that is tough. Depending on how the CAD tool generates the DXF it can cause
trouble. I know that GMFC only wants basic polylines in the DXF. It will ignore
most other entities. I think that includes arcs and splines. I know that in rhino
you can set the arc to polyline granularity when exporting DXF and you can get the
number of points down that way.

The GMFC software is not well documented for english. It can be a bit anoying.
the only thing worse than someting not making sense is it not making sense
and the only explanation you can get is in french.
crash_out
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Post by crash_out »

True..

Just for kicks, I redrew the two parts above to have the same number of points. Used Profscan to convert them, and GMFC loaded them up fine. Then proceeded to tell me that there was a different nmumber of points. I tried to sync up sections, and managed to do that, but still get told there are a different number of points...argh.
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