# Refitting a Grizzly G9972Z (Yangzhou Super Machine Tool Co CQ6128)



## ohland (Nov 13, 2018)

Things finally slowed down, my dog sprained her left "wrist", and we are waiting for a new oil furnace to be installed. I had to strip down the 11x26 lathe down to the bed so the furnace installers can get to the furnace....

There are a few bothersome things. About ten of the oil ball fittings have failed with the ball dropping down a little or entirely gone. The gearbox leaks badly, holding a fill for maybe two days before dropping out of the port (but still enough to make a mess). Dislike the 150 RPM slowest speed (extreme thread cutting, anyone?). So over the next few months, I intend to refit this G9972Z so it works better.

Plenty of mods. I like the retracting toolpost for threading. DC motor retrofit. Reverse tumbler. Just got to get there. Then I can get to my SIEG X3....


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## Mitch Alsup (Nov 13, 2018)

A device::





And fixing it:





There is another guy who built his own version of this 4:1 reduction but I can't find it right now.

This device allows you to run the lathe at full speed, or at reduced speed with a small reconfiguration.
I have been contemplating making one to be able to run my lathe lower than 70 RPM.


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## ohland (Nov 13, 2018)

I have seen where folks used a planetary gear reducer, it seems compact compared to the belts and pulleys in there now.

Just saw "lift up" or "flip up" thread tool. ChiefRex96 on YouTube. Now this is darned near genius.


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## coffmajt (Nov 13, 2018)

On my mill I replaced most of the ball oilers with zerk fittings and use a Bridgeport style oil injector to lubricate.  Much better getting oil where it needs to go == Jack


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## ohland (Nov 13, 2018)

Pull Gear speed reducer, 7:1, the G9972Z would turn at @ 21 RPM... wow...


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## Mitch Alsup (Nov 13, 2018)

I found the series; start with #1::


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## ohland (Nov 13, 2018)

coffmajt said:


> On my mill I replaced most of the ball oilers with zerk fittings and use a Bridgeport style oil injector to lubricate.  Much better getting oil where it needs to go == Jack



How to pull the press fit oilers? They are brass, and I think it would be like pulling a stuck case out of a die. Tap with a thread forming tap (no chips) and use a bolt, a washer and a 3/8 socket (most any size over bolt diameter would do) to pull it up...


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## ohland (Nov 13, 2018)

I could live with a max 500 RPM, so a fixed speed reducer would do...


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## Bi11Hudson (Nov 14, 2018)

While not the exact answer you're looking for, I built one for a Grizzly 1550, a 9X20 machine from Taiwan. It was several years ago, but might apply or be modified to your application. Try looking at:  
http://www.hudsontelcom.com/9X20Gear.html  and see if you could use the idea. Granted, it was for a much smaller machine, but you might be able to make it work. Depends on your spindle size and what size gears you can lay your hands on. There is no milling as such, everything was done with the lathe.

Conceded, it was to slow down a too high speed machine. If you have back gears already, it should slow the spindle to a crawl. Good, if that's what you need. A waste of time otherwise.

Bill Hudson​


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## ohland (Nov 14, 2018)

Bi11Hudson said:


> I built one for a Grizzly 1550, a 9X20 http://www.hudsontelcom.com/9X20Gear.html  and see if you could use the idea.



Been looking at the speed reducers on flea buy. A right angle reducer could be used with a vertically mounted motor, with the shaft pointing down into the reducer, and the output shaft would be about the same relative orientation as the original motor shaft.


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## ohland (Nov 14, 2018)

Parts list (Bummer, no edit for the initial post). By knowing the sizes, I can source most of this in other places...

Things that need to be replaced:
(10 ?) PLUBE001M - BALL OILER 6MM PRESS-IN 1.25 ea (P9972Z0108 BALL OILER)
(2) PCAP40M - CAP SCREW M8-1.25 X 35 (attaches saddle to apron) 1.00 ea
(1) DOWEL PIN 5 X 22 (P9972Z0315 LEADSCREW SHEAR PIN) my shear pin resembles brass... 2.20 ea
(1) PRP05M ROLL PIN 5 X 30 (fastens SHIFT HUB onto shifting fork shaft) 1.00 ea

Optional:
P9972Z0810 THREADED STUD M10-1.5 X 35 (fastens headstock down onto bed)
PN02M HEX NUT M10-1.5


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## mattthemuppet2 (Nov 14, 2018)

I really wouldn't go with a fixed speed reducer that limits your top speed to 500rpm, as that will limit you if you want to turn smaller diameter work or softer materials. A variable speed motor (DC or 3ph with VFD) is a much better option. That way you can get your low low speeds but keep your top end.


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## ohland (Nov 14, 2018)

Too much tool porn on flea buy. Many different Variable Speed Drives

Baah. DC motors it is...  90V Armature? I have 110v 20A, no desire to run 220 right now... Lots of red chinese stuff... 3/4 HP enough? The 11x26 has a YL8024 1HP 750W AC motor right now...


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## mattthemuppet2 (Nov 15, 2018)

the 3/4hp Consew motors have a big following and they're not that expensive - $100 or thereabouts.


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## ohland (Nov 15, 2018)

CSM100x and CSM300x are 115v.
CSMx000 have synchronizer for needle positioning, the CSMx001 do not. Though I do not know what that is...

FESM550 3/4hp 550w Speed : 0-3600 RPM
CSM-1000 Brushless Servo Motor 3/4HP 0-3600 RPM
http://www.consew.com/View/Consew-Model-CSM1000

CSM-3001 Brushless Servo Motor   1HP 750w


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## ohland (Nov 15, 2018)

Ho Hsing  http://www.hohsing.com/index.php/en/

I read of the G60, but the current site does not seem to have DC servos...

Dry hole, all models listed as 220v.

Oh my, sailmaking machines...


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## ohland (Nov 15, 2018)

Enduro Pro SM650-1
http://www.endurosaves.com/enduro-pro-sm650-1.php

Non-Positioner Servo Motor

110V            
Single Phase         
Cycles: 50/60           
Watts: 0-800
Torque: 0-2.4 Foot Pounds
Variable Speed to 5000 RPM
The Enduro™ Pro SM650-1 Servo Motor is designed to meet almost all basic medium duty requirements of various industry/commercial sewing machines. It utilizes extremely powerful rare-earth *Neodymium* permanent magnets. The motor produces almost no noise, saves energy (60-80%) and is brushless, speed adjustable and durable. It provides a high starting torque even at low speed or from a complete stop.

  By using a modern technologically advanced microprocessor, Hall sensor and Pulse-Width Modulation technology, the Enduro™ Pro SM650-1 can be set to rotate at different maximum speeds, in either normal or reverse directions, and can start with different accelerating speeds. It will stop automatically with any interruption such as in-line voltage, electrical surge, radio frequency interference or overloading. It is fully protected by the software and will give error messages indicating which problem is encountered. It even works well in environments with an unstable electrical power supply.

You are right about sensorless brushless motors and low startup torque. The "equivalent" to a brushed DC is a brushless DC with hall sensors. However these are manufactured overseas (typically) and the watts shown are the watts the motor consumes, not the actual output watts, which makes it very difficult to spec out.  (ex: I have a local with a 2.something KW spindle, my 1hp bridgeport cuts much faster, and better)  Don't buy anything you can't get a power curve from the manufacturer for.


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