Centroid Community CNC Support Forum

A bit of a 6 month update: The motor is still going strong. Working perfectly. Been machining a ton and having the more power makes such a difference. I’ve figured I can push it even a bit more than I was. A 3/8” 3ft carbide end mill doing 7k rpm with a 2.25mm stepover and 19mm doc at 1500mm/min fee...

That looks great! Nicely done!

Which encoder did you use? I’ve ordered one of the cheap omron knockoffs, but I’m a bit concerned that it won’t work with my 7k spindle.

It’s possible that if all the motors aren’t enabled the new motor on the rotary axis is giving a fault since it isn’t enabled and on. When you jog it independently it enables and is fine, but if you start on a different axis maybe it isn’t enabled and throwing a fault? Not positive that’s it, but ju...

I have been pretty busy in my small amount of freetime making parts on the 728 conversion. I am really feeling ready to graduate to a "real" VMC, but have zero space to do it so far. We are shopping for a house at the moment, but that is a crazy other story. I have a bit off work right now...

Hey Jerry, I am enjoying the new motor. It is night and day from the old one. I would say that as long as you aren't pushing the new spindle much faster than the 4250 rpm rated stock the stock bearings are probably fine. I ran them for a bit, but on longer ops at slightly higher RPMs they were getti...

Another little update, put on the bigger motor, changed the spindle bearings, and it's working beautifully. Been pushing the rapids and have gotten very happy with it all.

Another option is to add a G0 to the end of the program that puts the tool to the proper location at the end of the previous part. I'll do this when I have to probe a part on the mill. Makes sense to do it at the beginning of the program for the lathe I'd think unless you do a cutoff beforehand (whi...

For sure! It is a 3450 nameplate RPM motor. It is inverter rated, I am running it at like 78hz to get that 7k rpm. It has a 1.62 ratio pulley on it, so when the spindle is at 7k the motor is only spinning 4350 rpm, so not too much over the nameplate. When I bought it the ebay ad said it was rated fo...

I just got back home this past Saturday and I was excited to dive into the spindle motor upgrade. I had seached eBay for quite a bit while I was away for work and ended up with a used like new marathon 2hp motor and an FM50 2hp single phase VFD. Thankfully I got quite lucky with the motor and the pu...

Richard, I own the 728VT but have not see the 833 in person. I have seen some videos of a conversion to that as well. I would say that the 833 is the better choice if you think you might be doing anything but aluminum. The 728 does have a slightly faster max spindle speed, which is handy for small t...