Still a Drag?

I had a great weekend. I had to mow the grass but that is expected and still makes for a great weekend. For this Blog it was great because I got to put a lot of run time on the HB2. About six hours in total.

I even ran the Mayan calendar in a 7.75″ diameter on some Corian. I’ll post some pictures soon. The detail was excellent.

I think I may still have a little drag on the axis screws. It didn’t bother the CNC work this weekend. I have some spray bearing grease I will inject behind the Thrust bearings and see if the intermittent slight rubbing noise goes away.

If the grease doesn’t help, I already have a plan to put a “step” at each end of the screws and just remove the thrust bearings. That way the only thing the screw end can contact is the center race of the bearings.

That’s what I should have done in the first place. I did find out how easy it is (when you have a lathe) to modify the ends of the axis screws.

How I noticed what may be the rub is I changed my micro-stepping from quarter to eighth. I now run 8,000 steps per inch rather than 4000. That’s 0.000125 inches per step, way too fine than really useful . This was done not to increase accuracy but make the steppers run a lot more quite (but also a lot hotter).

Quarter stepping was still more accuracy (0.00025″) than I needed and it is supposed to provide more torque. The motors run cool. The noise however is more than 3 db higher and the twin Y’s were driving me crazy with their loud sound. Now I hear a sweet soft tune.

I had to bump up the stepper frequency in the software but that was no challenge for the computer I use to run MACH3.

All these things are minor tweaks, even the rubbing, but that’s part of what I like to do. It’s like writing computer code, the work is never complete. Always one more detail to add or I feel a need to “tweak” something.

Yes, I am having fun