Stepper motors loose torque as speed increases therefore they have a maximum speed at which they will run, exceed this speed and they will stall. Not all, but most stepper driver circuits do not or cannot compensate for what is termed “mid-band resonance”, a phenomenon from which all steppers will suffer as a result of their basic design and operating principal. It is this resonance that causes a stepper to stall prematurely thus reducing it’s maximum available speed.
If like me you use steppers then with this simple little device you could possibly double the reliable rapids (G0 moves) on your machine.

I recently spent an hour or so reading and re-reading this thread on the zone http://www.cnczone.com/forums/stepper_m ... er-23.html and although convinced I just had to prove it to myself. Guess what, in my trial, it easily doubled the feed rate before my stepper stalled. This device has been patented so it’s only suitable for personal use but it is so easy to make you really just have to try it.

My test dampener is pretty quiet in operation - it has been made from HDPE and the rollers are from brass (there is a cover which fits over the front to stop the rollers escaping but this is not shown in the photo).

There is little point in going into the details of its operation here (even if I fully understood them) because it is fully described on the Zone - it perhaps looks similar to a flywheel but if it doesn’t rattle then it doesn’t work.
Physics sometimes reveals itself in strange and mysterious ways.

Tweakie. Attached files

 

Good fine,Tweakie. I'll try to make one and see how it works. I just have to see how I'll mount it on a single shaft motor. I've read in the thread that they drill the motor but I'm not sure yet how to do it correctly.

 

Yoram,

Some have been mounted on the coupling. Possible perhaps ?

Tweakie.

 

You know what they say :- " If it ain't broke, don't fix it ".

Tweakie.

 

For anyone who hasn't seen these before, this is what I had on my last machine (before having an auto-damping controller):

http://solsylva.com/cnc/dampers.shtml

They work marvelously. My machine wouldn't go more than about 50ipm without them, but hit 150ipm with them. They only cost a few dollars to make.

 

The problem is you need the shaft to extend from the end too and my motors don't have the rear extended shaft.