I did some horse trading for this 6 inch Vertex super spacer, about $80 in materials, and a couple hours labor But it was missing something....I still had to turn the handle and I couldn't hook it to the computer. But.....I can fix that.
With the handle removed, it looks like that is a perfect place to put a pulley.
So, make a little box to house the belt and mount the NEMA 23 Stepper.
Finishing the cover
The finished housing, motor side. It just clamps onto the Vertex housing.
And in position
The belt installed, 2:1 reduction
With the cover installed. I did not want to modify the Vertex at all so I left the shaft intact. The original handle will still fit with the motor on.
So I made a cover that just screws into the housing.
It still allows vertical or horizontal operation by rotating the motor housing around the mount.
It worked perfectly....well almost :tired:
The thrust ''bearing'' on the outboard end of the worm shaft was a wave washer rubbing on cast iron. Not the best system, and it started seizing on me. It needs a real thrust bearing but a 15 x 21 x 4 mm thrust bearing proved to be nonexistent. No problem.....Just because ‘’they’’ don’t make a 15 x 21 x 4 mm thrust bearing, doesn’t mean that one can’t be made. All it takes is two grade 8 washers, a bronze washer, and some 2mm bearing balls. Ok the grade 8 washers ain’t bearing steel, but close enough for this application. A little operation under load will work harden the surface and they’ll last quite a while.
A little surgery on the parts and instant (almost) thrust bearings.
Loading the bearings
The cam housing with the the thrust bearing in the new pocket.
The worm shaft and cam housing with the new thrust bearings.
Running in the new thrust bearings. Over tighten a bit, run for awhile, rinse repeat until I'm happy with the way it feels. Then adjust to the proper preload.
And the finished product
3.6 million steps per revolution or 10,000 steps per degree. Adjustable to zero backlash. A little more time to install the new stepper driver in the cabinet, then a few program modifications and the new 4th axis is alive.
After a few mods to a Grizzly tailstock it's set up.
The first test cut !
This is what the screen looks like. The Z and R(otary) axis are turned off on this pic.