CNC Upgrade and Fretboard program

[phavriluk]

Oh boy can't wait to see how your fretboard comes out

I'm in awe of this!

[Diane Kauffmds]

Well sports fans, this bad girl is truly finished! Much like my second guitar that I named Delilah (the bad girl), this cnc has truly tried my patience. I finally got the new limit switches working by jumpering out each axis pair. They're much better switches, but they're 2 wire and my board takes 3 wire switches. I could get 1 to work in each axis, but when I plugged in a 4th, none of them worked. But, they're working as intended in all axis now. I've wrapped wires and inserted them into the slots as much as possible to corral them.

I ended up installing a 16mm ballscrew. That's quite an upgrade from the 8mm lead screw that I had originally installed. I bought and installed a 16mm ballscrew for the z-axis, but the stage was too narrow, and I couldn't properly anchor it to the guide rods. I started to buy a different model, but decided not to. While my design on the z-axis isn't pretty, it's damn accurate and solid. So for now, it stays.

The wood is gone and I cut metal plates in its place and replaced each end with 2080 t-slot extrusion. The thing weighs a ton now. I installed what I call "table guides", which are 1" aluminum angle, meant to ensure the table stays straight no matter what I'm cutting. But, that 16mm ballscrew isn't going to allow the table to deflect at all.

I'm still using "sliders" which are 1/8" thick aluminum angle wrapping around the sides to under the table. Under the table, it rides on another angle, attached to the frame. Both surfaces have heavy duty UHMW tape, which they slide, so there's no friction. But, I upgraded from 3/4" angle to 1" for the table itself and 1 1/2" for under it. My husband, both German Shepards, and I, can all stand on it and there won't be any movement or deflection.

I upgraded the motor for the Y-axis to the same high torque nema 23 I'm using on the z-axis. The x-axis still has the nema 17, which easily handles it.

I had to slow down the maximum speed for the Y-axis. Apparently Nema 23 motors (except for closed loop) are limited to 1000 rpm. Nema 17 motors can run as fast as 2000rpm. This wasn't an issue until I installed the ballscrew. In order for the table to move, it takes a lot higher rpm's. So, where I could run the old table, with the small lead screw at 80ipm (or maybe faster), the motor gets unhappy at anything above 60 ipm. So, I've Programmed it so the table can't move faster than 50ipm. I'm in no big hurry and I don't make fretboards and necks for resale. I never run the cnc programs more than 20ipm, and mostly I stick with 14ipm. So, it doesn't bother me.

So, here she is in all her glory. I have 11.5" of active cutting across the x-axis, 6 inches of z-axis movement, and my big goal was to have a cutting area of 22" long on the y-axis. I have 24" of cutting length, right on the money. The entire cnc unit is 16" wide x 31" long.

The table is solid aluminum t-slot, with a spoilboard screwed to the slots. I top it with another spoilboard. As far as table accuracy, it is off by 1/2mm from dead center. I can live with it.

She's obviously homegrown and not a sleek name brand cnc. But, she'll do everything I need very accurately and quietly. She still sounds like R2D2 when she's cutting.

[Kevin Sjostrand]

That is a purty beast!

[Diane Kauffmds]

Well, I keep changing things slightly as I think of them. I took out the guide rods from under the table. The table rides on 2 aluminum angles, each with UHMW tape, so there's no friction. I added side table guides, made of aluminum angle. I've experimented with smaller pieces on each side and it works brilliantly. I'll replace those pieces with 1" angle today, which will run the length of the cnc, today when it arrives.

The biggest addition is the new computer system, dedicated to the cnc. It's now totally autonomous.

I found a mini pc, which is runs windows 11 pro. I've paired it with a mini Bluetooth keyboard and 7" monitor. All I'm putting on it is the cnc grbl software, and I'll keep gcode files that I reuse, like fretboards and bridges. I'll use my laptop to design things in Fusion360, then use VCARVE to generate the codes. I can transfer the gcode files to the CNC via Bluetooth. It works perfectly.

Now it can run from across the shop without a bunch of wires to trip over.