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Hello, any CNC guys out there who can help me with my curved truss slot. I am using Cut3D and VCarve Pro.. I have tried drawing the slot with the curved bottom, exporting it to a .STL and bringing it into Cut3D to generate GCode.. I have also tried importing it into VCarve Pro and I still have no toolpath that works the way I drew it.

I am making a hollow Cabronita with a one piece maple neck and a traditional curved single action truss rod.. Currently creating a jig to cut hole for head-stock access for adjustment. The drawing contains all of the info I used to create my slot. Creating all my other tool paths have gone smoothly and thought the curved slot would be a breeze. If anyone has any experience i would appreciate it..

Thanks
Costantino

I'm using different system (rhino and VisualMill) but in my case I use an engrave path in my CAM.
In my CAD program I extrude my truss rod curve sideways about .1 on each direction and then project a line to that surface. Back in CAM I program an engraving path to that projected line and my machine follows that curve perfectly in as many levels as I like.
Hope this makes sense...

That's going to be very tricky to do with those two software packages. If it's possible at all, you'll need to trick it into doing something it doesn't have the built in features to do.

The latest version of VCarve pro has the capability of importing one 3D model and doing a rastor cut of it. Possibly try making a model of rectangle slightly larger than your neck profile with the curved slot in it and then you could probably do it with either Cut3D or VCarve Pro 8.

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I made a solid model of the slot and brought it into VCarve . I get a results that are wider for some reason, with the tool-path wider than the .25 I made the slot? I have made curved surfaces, head-stock transitions, and body belly curved surfaces and it went ok. Drew it in MOi3D and exported in .STL, open it in Cut3D and generate tool-path, save as a file for VCarve to make it work with my body or neck.

If it doesn't have simple surfacing operations then the only way I see to do it will be the way you have imagined above. You'll have to take a LOT of measurements off the model and generate a LOT of too paths to get the resolution of the groove smooth...and considering the tool offset from the groove surface...that's a lot of work.

If the controller will accept the command....and if you know the start and endpoint of the arc AND the radius of the arc...you could insert the operation into the g-code. That would be tricky but it might be worth considering and you'll definitely learn something dinking about with this.

Whatever you end up doing....know that is going to cut the groove at the designed height and shape near the apex of the curve...and then go a little bit deeper...and have a slightly rounded bottom than designed as it gets near the ends. Something you might want to think about since you'll have to mate this with a corresponding strip above the rod in order to force the curve.

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StuMusic

Thanks . . . I though this would be a simple operation for Vectric.

I have a solution for the moment. I created the geometry that I wish to have at the bottom of the slot, and cut it out on its own from hard maple, same material as the neck. This way I can create a .75 deep flat bottom slot .25 wide. Then I can glue in the arched wedge.

The fluteplus gadget should make pretty easy work of that. It is free with a suggested donation as I recall. I know I was happy to pay it as I get really good use from it in Vcarve,
Mike

Oh man! that was it! Flute Plus gadget! Thanks a million for the info! I donated for the file also. Took 2 seconds

I have .75 at the beginning and .625 at the end of the curve! iI sat here for 2 days pulling my hair before I posted and asked for help..

Thanks for all the replies