Setting up for a curved cut

Thanks for allowing me to join this group. I just purchased a 48x30 CNC for hobby work. I do a lot of work with wine barrel staves and wanted to do something with the new CNC. One of the items I build is crib boards by hand. My question is that is there program that I can use to follow the curve of the stave. I have looked but being new I seem to be googling blindly as I am not yet aware of what I should be looking for.


Hi @JKexperience, welcome to the platform. Maybe you can find something you need in this video on YT.

@JKexperience I will add to @GeorgeV welcome to the group.

It’s a good video that George linked to. The only thing missing is how he made the 3D model of the stave that he carved into. I saw in the comments that he intends to do another video on how to do that. To use the “project onto 3D model” aspect of the tool path, you first have to create the 3D model.

You will need that information to help you decide on the CAD/CAM software that you will need for your intended projects.

Alot of the work I do is with Wine Barrels, so I did end up following the person. I feel there is always something new to learn. But you are correct Qwilki he never does show how he got that 3D image on the screen. You also have the other curve of the stave that runs the opposite direction. Something in my head tells me that there must be some sort of zeroing sensor you could mount to the actual end of the router and be able to set that to a distance. Maybe someone out there smarter than me can build one and market it.

This reminded me of a post awhile back.

There are two general ways that I see to solve the problem of carving on these compound, maybe irregular curves.

The first way would be to create a 3D model and project onto 3D model but how to create the model? You could use a laser scanner, not exactly cheap but getting more affordable all the time or try photogrammetry software like Meshroom, free and open source, which creates a model from a bunch of photos that you take.

The other way would be called ‘auto leveling’ or ‘surface mapping’ where a program probes the work piece in a grid pattern and then adjusts the G-code based on the curved surface that was mapped out in the probing step. This short video shows the surface mapping in Estlcam which is not free. I think that cncjs also has this feature. I have also found OpenCNCPilot that has this feature.

In order to do the auto leveling/surface mapping method you will need some kind of probe. A regular low cost probe can be used but you have to make the surface of the object electrically conductive. I’ve seen tin foil used for this then one wire of the probe circuit is connected to the tin foil and the other to the bit. There are also more expensive probes called 3D touch probes which don’t require the surface to be conductive because they basically have internal switches that activate by pressure or movement on the end of the probe.

That’s what I think I know about what you are trying to achieve. I hope that it at least you won’t be googling blindly now.