Lutherie - Guitar Building Tools

One of the main purposes of building my MPCNC was to make tools, fixtures and jigs for lutherie (guitar building). A friend of mine is a guitar builder in Fairfax, VA and I hang out in his shop when my schedule allows it. I have noticed that while lutherie requires specific tools, many of them are either expensive or poorly made.

So, an ongoing project of mine is to build tools for guitar building and when possible, make them better than the commercially available tools. I will post pictures and details in this thread as I make progress on the various tools I’m making with my MPCNC.

My first project is a side bending form for a tenor sized ukulele. I decided to start small to conserve material and time, but the same process would be used for a full size acoustic guitar.

I’m using a compression bit to cut 3/4" plywood pieces. These pieces will be stacked to create a ~6 inch thick form that is the same shape as half of the ukulele body. I’ve cut a couple of these already with a 1/8 inch compression bit, but I’m going to hold off on the remaining six pieces until the 1/4 inch bit arrives that I ordered today.

Here are some pictures of my progress thus far:

The STL file is attached - be aware that I didn’t care about thickness since I just extracted the outline in Estlcam. Also, I changed the file extension to .txt, change it back to .stl before opening it.

ukulele_outline_stl.txt (363 KB)

Probably better in the future to just zip the attachments so people don’t have to change the filename. Not that it’s difficult, but there are less computer savvy people out there. :slight_smile:

Would this scale directly to a soprano, concert or baritone size? Or would the curves need to be restructured for different sized instruments?

*I should clarify that I didn’t design the shape of this ukulele, I found it online and modified the model in an existing sketchup file and exported an STL:

Regarding the possibility of using it for different size ukuleles, the short answer is that I probably would just find plans for the particular scale length of ukulele that I’m building.

The size and shape of the box of a lute is not strictly important. You can actually find ukuleles that have square boxes or pineapple shaped boxes. So, yes it is theoretically possible to do what you’re asking. You could probably even build a shorter or longer scale length ukulele without adjusting the size of the box at all, even if it might look silly. Gibson generally uses the same 24.75" scale length for all of their guitars, regardless of the box size.

I hope that is somewhat helpful. Here’s a link that explains scale lengths for guitars:

Thanks for the feedback, I will upload zip files in the future instead of changing the extension.