The Home Machinist!

Bill Shields wrote: ↑Tue Jun 20, 2023 10:20 pm Driving it with a vfd will most likely not help until the imbalance has been corrected

I'm talking new 3 phase motor with a VFD, the old motor goes to metal recyclers.

So what caused the vibration to appear? Being mechanical by nature, most vibration problems appear because something about the physical construction has changed. When a motor begins to vibrate, I think of bearings going bad, (generally noise) shaft being bent, or something about the rotor itself be...

leaving the wiring to the experts, a basic question begs to be asked: why did the motor / rotor suddenly need to be balanced? generally when something like that occurs (sudden need for balancing) -> it is a harbinger of bad things to come... As I mentioned at the start of this thread, the motor dev...

I don't have a PM932... but I note a couple things odd about your wiring and diagram. One, it appears in your drawing that either the AC 220V IN or the X Power Feed is reversed. In the picture terminals 15&16 are bonded together with a shorting strap. There is an insulating divider and then ter...

Does anyone here own a Precision Matthews PM 932 with motorized Z elevation and X power feed bench top mill that they purchased in and around 2017 - 2018 ? The short of it is mine developed a wicked vibration, which I traced to the motor, took the motor to motor repair shop #1 and in a brilliant mov...

Chief is right, it's- MACHINERY'S HANDBOOK - A Reference Book for the Mechanical Engineer, Draftsman,Toolmaker and Machinist. My 21st Edition doesn't have a ISBN number just a Library of Congress Catalog Number - 72-622276 I would check on eBay for copies, the content is pretty much the same in comp...

Are there any books to read that would be helpful, YouTube channels to watch and learn? YT content that I recommend - For entry level machining - mrpete222 He explains well, with good demo projects. I tend to like - Oxtool Stefan Gotteswinter Robrenz Joe Pie All four of them are very detail oriente...

McMaster has them - https://www.mcmaster.com/products/~/?s= ... ping+tubes

VelocityDuck wrote: ↑Mon May 15, 2023 2:01 pm What does the 3 or 4 denote?

I wouldn't think Jacobs because I didn't think there was a JT4.

This is what Jacobs lists for R8 shanks -
http://www.jacobschuck.com/arbor/54.html

The some import chuck adapters seem to drop the JT when they label the arbors.

The R8-3 and R8-4 are probably for drill chucks too.

I'll put first dibs on them, sent you pm.

Yep! Head of the screw is eccentric. And what I thought were threads in the nut were just scratches. So what you typically use these for? I have no idea what the previous owner was into. They're super low profile work holding wedges/ clamps, the eccentric head of the screw swings one of the hex fla...