An Electronic Lead Screw controller using a Teensy 4.1

[WobblyHand]

It actually wasn't working that well - it would occasionally crash. It crashes on all kernels > 5.15.0-37 to the best of my knowledge, just the frequency. A week ago, I got forced into an update that bumped up my kernel, and I have been having troubles ever since. So I tried to install everything in a virtual machine. I have yet to actually get things to work there. I need access to USB in the VM and that is where the issue is. Even compiled a cli based teensy loader, but it appears it is not even connecting to usb at all.

 

[AlanB]

VM's and USB is not the best of combinations. I had good luck with Windoze 8.1 but that wasn't recent and Teensy 2. I did something with a 3.something as well that seemed to work. But nothing recent. I did the Pico work from a Raspberry Pi. That seemed to be well supported.

 

[WobblyHand]

Looking into the Teensy loader, it seems that they really exercise the USB in multiple ways. I don't know if a vm supports this level of "thrashing" and mode changing. I see the vm dropping the connection and lsusb no longer detecting the device. Seems that I am beating a dead horse on this but it annoys the daylights out of me that it only seems to show up on my machine. And it's more annoying that the onset was seemingly OS software related.

 

[WobblyHand]

Working on the above, makes my head hurt.

Decided to design the motor mount plate. Will make it out of a piece of 1x4x5 A36. It will be good and sturdy. I have about 24 inches of the A36. Here is an isometric view with the motor.

I have to change the hole to the left of the motor to allow the motor cables to get through! Made a mistake! Was so happy with the design, then thought - hmm, I wonder how big the cable connectors are? Think the easiest thing to do is to make a slot all the way to the edge. Nuts, back to the drawing board... This should be better!

I made the slot wide enough to allow both cables to stack vertically, which should give me the maximum X displacement for tightening the belt.

Now I have to go back and fix up my technical drawings. The downside of FreeCAD is they have not solved the topological naming problem. This means changes to the model can cause renaming of faces and edges - the same faces and edges used in the technical drawing package. So a bunch of dimensions got hosed. The price we pay for a "free" drawing package. Doesn't take too long to fix things, but is a bit of a pain.

My first two belts came in today. They are the 3M384 motor drive belts.

I better hurry up and make the motor mount! And I better figure out how to hog out the cast iron base of the lathe, so there's a place for the motor to fit...

 

[AlanB]

Looking good there.

I've heard there are a couple of issues with FreeCAD. I hope they can come up with a resolution soon. OpenSCAD is great for 3D printing, but it doesn't really support CNC machining properly.

 

[WobblyHand]

Looking good there.

I've heard there are a couple of issues with FreeCAD. I hope they can come up with a resolution soon. OpenSCAD is great for 3D printing, but it doesn't really support CNC machining properly.

It's a bit buggy, but I do have to say that it does work, mostly. Of course, as a new 3dcad user, I still have a lot to learn yet. I made some bad choices in the model and am slowly correcting them. I should have drawn everything in a simple local coordinate system and then translated it to the true location. But I didn't. So I'm fixing that as I go along. Basically, new user modeling issues. I'll figure it out.

 

[AlanB]

When I look at my early OpenSCAD files it's pretty bad. Many things to learn and improve.

 

[WobblyHand]

Yesterday, hacked off a piece of A36 and started whittling it down to size. Got a ways to go. Need to remove 5mm from the thickness. That takes time on a small mill. Really need to get a carbide roughing mill to improve the removal rate. Need to remember to mix up some more AnchorLube. The regular cutting oil smokes too much and wrecks my sleep. Forgot that, used the normal Tap Magic and had a bad apnea night. So I am dragging today. Hope tomorrow is a bit better.

 

[WobblyHand]

Finally milled this piece to size. Here it is while I am pondering what to do next.

Fly cut the face. Lots of blue chips. Cleaned up everything for the picture. You all don't need to see a big mess, do you?

Those four slots in the drawing are through 20mm of steel. Will have to drill them, else my end mills will get beat up. I will put in the U-slot last, after I do the pocket on the back side. Put instructions on the drawing to remind me of that... I'll get it set up tonight and have at it in the morning.

 

[AlanB]

Does it need to be steel?