TAP Files - Conversion to NC?

I brought another “engineer” on board. We get down to the generation of the file for the machine and I’m looking at a .tap. I told him I need .nc. He says he cannot put out nc. Ok great. So in his file he does not specify feedrate or spindle speed. My question is simple. Is this even worth attempting to put through Motion or did this guy just zing out into left field?

How do you create a machine specific file from a design without it being machine specific? How does your engineer create the “.tap” file?

.tap is one of the file extensions typically used for G-code — .nc is another.

It should work to load a .tap file into Carbide Motion and then send it to the machine — so long as a suitable post-processor was used to make it, and the feeds and speeds and so forth are appropriate to the machine.

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Man I have no idea. I gave him the STL. He used Artcam to do what needed to be done and then put out a file with a .tap extension. Looked it up and was surprised to see it was once upon a time used by the commmodore 64 lol! I had one of those back in the day. And then of course found it was an Artcam output. I told the guy from the beginning… I need an .nc file. Guess he missed that part. Well he missed other pieces as well such as proper orientation, missing border, bad thickness spec. Fired him. He was a bad engineer! He obviously didn’t listen to details.

However, that raised another issue in that the output and detail from ArtCam was much better than other applications we used. Perhaps we are doing something wrong in C2D. I’m not sure. These are very small and very detailed pieces. I’m running tapered cutters like the Amana HSS1304 for example. I have them all from 1/8 through 1/64 just in case we ran into a detail issue.

Hey Will, how’s it going? I’ll give it a shot. Was sort of afraid to do it because of another syntax error post that I read. And I’ll post the results up here.

CNC files are just typically asci text files. If you’ve had experience writing gcode it would be easy enough to add the M3 and spindle RPM along with feedrates for the different tools. You could edit them in notepad or download one of the nc backplotting programs. Something like this.
Predator CNC Editor software | Backplot G-Code | DNC | File Compare (predator-software.com)

I’m dating myself but I used to write ncode by hand 40 years ago before CAD/CAM. All I had was my pencil and a calculator. :slightly_smiling_face:

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You can check for syntax errors by connecting to the machine, going to the MDI (enable it in Options if need be) and sending $C (putting the machine into check mode) and then loading and sending the file — Grbl will process all the lines but not move the machine — send $C again to restore normal operation.

Open the file in a text editor. Is it G-code? If so, just rename it to .nc

.tap (tape), .ptp (paper tape punch), .min, .nc, .cam, .mpt, .mpf, .mac are all exensions for gcode.
Some machine controllers like a specific extension. Some don’t care as long as the format is correct.

If it’s gcode, and it simulates well & gives the detail you want, ask him to use a postprocessor that outputs spindle & feeds. Artcam had over 400 posts. One of them has to be close to what you need.
Perhaps one of these:


I recall that .tap files are generated in Mach 3. ArtCAM also generated them. I use Carveco (developed from ArtCAM) which can handle multiple filetypes but .tap is not listed. Nevertheless, I found this page link on the bottom of the page on Carveco’s site. which takes you here: Look under relief files.

FWIW, my understanding is that providing the .tap file was generated using a Carbide 3D post processor, you should be able to to change the filetype from .tap to .nc without issue, It will enable you to view, run and edit the g code as required. Using the free CAMotics app or NC Viewer you can view the files you obtain just by changing the filetype.


From the wiki — extensions which work in Carbide Motion:

  • .nc

Extensions which should work:

Proprietary extension for a specific case:

  • .egc (encrypted G-Code for encrypted files for Carbide Motion)

I tried to follow this link but it appears to be broken.

Fixed it.



But note that it now uses a .nc file extension

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Tyvm :slight_smile: Definitely appreciate your help.