Rhino - CNC problem

Attachment 268118
This is maybe more CNC/CAM setup problem than Rhino problem. If you know a better place to post this please chime in...
I am new to CAD and even newer to CAM (have limited experience with MeshCam so far). I am working up this guitar design with aspirations to CNC rout it ultimately.

Problem: As you can see, the deck ankle changes from zero to 2.3 degrees just ahead of the bridge.
The result is that a 3 axis CNC router is going to have trouble putting that negative angle in the neck and pickup pockets. It's only gonna give me vertical walls.
I can think of 2 solutions:
1) Go ahead and rout them vertical and then undercut them by hand. Yuck.
2) Do these 3 pockets as a separate CNC run after tilting the body to make that foredeck horizontal. This will require some careful consideration to make sure the depth of the neck pocket is precisely correct.

As a neophyte (soon embarking on CNC kit build) I am just wondering about the feasibility of the latter approach.
I still have an immense amount of work to do to get this CNC/guitar "factory" underway but this is the problem on my mind at the moment.

(I have been building guitars with hand tools for a while. This is a foray into new territory!)

Steve

Given the description and the one screen shot it is not totally understood since I am not a guitar builder. Pockets with under cut walls are a challenge. If the surfaces aren't critical hand cutting them might be fast. You might want to use a special shape cutter and manually program the tool path if the shape is simple. Better description and pictures would help a lot.

Quote:

---

Originally Posted by spincaster

Given the description and the one screen shot it is not totally understood since I am not a guitar builder. Pockets with under cut walls are a challenge. If the surfaces aren't critical hand cutting them might be fast. You might want to use a special shape cutter and manually program the tool path if the shape is simple. Better description and pictures would help a lot.

---

Thanks for your thoughts. Undercuts are an interesting problem indeed. A tapered bit of some kind would possibly do it as you suggested.
I think however I'm gonna take the easy way out and just make the pockets vertical. It's not elegant but it is workable.

Steve

Quote:

---

Originally Posted by s_tones

Attachment 268118
I still have an immense amount of work to do to get this CNC/guitar "factory" underway but this is the problem on my mind at the moment.
Steve

---

So if you are going to be pumping a lot out, I would make the angle jig to reset the deck in plane. The careful consideration wouldn't really be too hard. You would just reset the zero at that top deck, then the depths of the pockets will be the depth of the pockets... If that angled deck is actually a "curved surface", then you could be sure the top edge of the pocket is set correctly by grabbing that dim from Rhino, then passing that to the machine/pocket.....

Steve,
Try milling the pickup pockets straight. The slight variance in depth from front to back is neglible and can be absorbed by the mounting ring. (Think Led Paul, where the rings are thicker in front than back)
I'm assuming your design is for a bolt-on neck. A vertical wall would work here, too. The obtuse angle is then milled on the end face of the neck heel when the back radius is being cut to eliminate the gap. In other words, the very end of the heel won't be 90 to the fretboard.
If it's a glue-in, the fingerboard could feasibly be extended slightly over the end and cover it completely.

Hi.
Just a thought...you could connect the neck pocket with the neck pickup pocket as if it was a setneck guitar or like the rear trem routes in a start. the fingerboard (extended if necessary) and the pickup ring cover the gap.