G9972Z DRO and Brushless VFD mods

[Road_Clam]

So been very busy the past 4 weeks with my 11x29 lathe. Lots of cool upgrades going on ! First is the Little Machine Shop magnetic DRO kit. After much research I opted to buy the LMS "universal" kit so I could custom configure the whole system. You get a 40" long scale and you cut it to length(s) as required. Glad I did this as opposed to trying to fit "pre cut" scales to my lathe.

Digital Position Readout, 3-Axis Bluetooth Universal 5515

DRO Packages 5515 Fits milling machines with less than 32" total X-, Y-, and Z-axis travel; Displays on any Android tablet with Bluetooth capability; ...

littlemachineshop.com

Took a LOT of trial and error mock-ups and fitment considerations but in the end I got everything to fit very nicely on my 9972Z's cross slide. The biggest problem is the "X" axis cross slide gib adj screws are on the same side as you need to mount the scale, and I needed to maintain access to the screws. I ended up completely removing the saddle and drilled and tapped M4 holes in my benchtop mill as it just seemed easier and more precise with locations.







The "Z" axis was much easier mounting the scale but mounting the sensor was more of a PIA as far as complex brackets. The most important suggestion I can make for guys wanting to do a DRO mod is give yourself plenty of adjustment options by machining slots in your brackets ! Here's some pics of the Z axis





I added stainless woven braid sleeve over the existing sensor cables to help minimize any risk of wear. Used some shrink tube to help cinch the ends.



The bluetooth DRO is nice as you can use any tablet.




Next up is the Brushless VFD conversion. Finally got tired of belt swaps. There really isnt a bolt in kit for the 11x29 so I had to get real creative. This has been a LOT of work, (still not finished yet) but got all the mechanics finished. Getting all the belt center to center dimensions just right was a PIA but again after a weeks worth of trial and error mock-ups I got all the pulleys aligned and I can still swap belt pulley configurations if needed. The OEM Grizzly motor is 1hp and the new brushless motor is 1500W (2 hp) so this should be a huge improvement in speeds and torque. Here's the universal kit I purchased :

2 hp 110V AC Industrial Servo Motor Controller Driver Universal ShopSmith Sheave | eBay

One A type single V belt Sheave Pulley. 3.05" and fit our servo motor. from inferior induction motors to modern design servo motors. A complete servo motor as seen in images. One 1,500 watt (2 HP) servo motor.

www.ebay.com

Had to fab a motor adaptor plate out of 1/2" aluminum plate





I bought a second motor pulley from Grizzly and modified the pulley to fit the brushless shaft. I had to machine a adapter sleeve, fab a special "stepped woodruff key" , and I had to increase the pulley's counterbore depth so I could attach the shaft nut.





After a week's worth of screwing around with belts alignment's I got it right and the system works excellent.



So the last phase of the build is to neatly contain all the electrical switches and speed controller in one box. Not sure how i'm going to do this but I will update as I make progress.

 

[markba633csi]

I would try to get a schematic diagram for the controller from the vendor. If they go out of business and you smoke the board are you going to be dead in the water? I wonder just how durable the controller is. Unfortunately these import brushless controllers don't seem to have a great track record from what I have seen.

Fortunately, there is a guy who can fix systems like that- his name is Pete at:
www.olduhfguy.com

 

[The Custom Crafter]

Next up is the Brushless VFD conversion.
So the last phase of the build is to neatly contain all the electrical switches and speed controller in one box. Not sure how i'm going to do this but I will update as I make progress.

Rich.
Your work is outstanding.
We would love to have the measurements for the plate so that other G9972z owners can do this build.
Optionally we would consider buying them from you and making a kit for this lathe. That or listing your kit on our site.
We of course have replacement main boards in stock and can ship out immediately if it fails.
As for the schematic: Contact me and I will provide information on what taps are available for control of the motor.
By the way, my main lathe just failed. When I contacted the dealer and the manufacturer, no parts were in country.
Looking at the motor, it was brushed. Why waste any time on that. I installed this 2 hp motor. It was much easier than your install. The video is too large to upload on this site so see

The performance improvement is awesome.
I am doing the electrical conversion right now and should have a video by Sunday night.
It will show how to build it into the existing control box using the emergency stop, the chuck key guard and a instant stop to energize reverse. Maybe a few fixed rpm features as well.
Thank you.
Dan

https://www.ServoMotorKit.com

 

[Eddyde]

The video is too large to upload on this site so search YouTube withe this sentence

Bolton B290VG Lathe Motor Repair Upgrade 2 HP Servo BLDC

You don't have to upload a video here, just copy paste the URL in your post and a link will appear:

 

[The Custom Crafter]

Done

 

[Road_Clam]

Rich.
Your work is outstanding.
We would love to have the measurements for the plate so that other G9972z owners can do this build.
Optionally we would consider buying them from you and making a kit for this lathe. That or listing your kit on our site.
We of course have replacement main boards in stock and can ship out immediately if it fails.
As for the schematic: Contact me and I will provide information on what taps are available for control of the motor.
By the way, my main lathe just failed. When I contacted the dealer and the manufacturer, no parts were in country.
Looking at the motor, it was brushed. Why waste any time on that. I installed this 2 hp motor. It was much easier than your install. The video is too large to upload on this site so see

The performance improvement is awesome.
I am doing the electrical conversion right now and should have a video by Sunday night.
It will show how to build it into the existing control box using the emergency stop, the chuck key guard and a instant stop to energize reverse. Maybe a few fixed rpm features as well.
Thank you.
Dan

https://www.ServoMotorKit.com

Dan, thanks for the positive comments. I'd be happy to work with you to help construct a G9972Z bolt in "kit" .

FYI if I'm not mistaken the more popular G0602 10x22 lathe uses the identical drive configuration so the kits would work with both lathes.

 

[The Custom Crafter]

Hi Rich.
I actually work best with the part in hand versus a draft or a software file.
Also, every build so far that wanted low speed for threading has not needed the additional pulleys. They set it on the mid range
and it does everything they need. To use just one pulley/sheave will require moving the motor forward to align with the best mid range sheave.
You will know which one is best in a month or so. The bracket you made would likely suit both styles
Thanks
Dan

 

[Road_Clam]

So the next phase is configuring the VFD controller components . I bought a universal 6x9 ABS junction box to allow some additional space for wiring, and to provide added mounting options. Really had no idea how i was going to mount the components initially. So after a lot of thought and mock-up trials i came up with a good configuration that allows easy access to the adjustable speed pot switch, and the controller programming buttons. I also have unobstructed door opening access to the lathe pulleys and change gears. Last step will be adding the E stop switch , and the digital tach display on the front of the 6x9 junction box

 

[Road_Clam]

So we have a finished lathe ! Ended up buying a small 120v to 12v DC 3a output switch converter to supply DC voltage for my DRO unit, and my Digital Tach display . Both required about 1.5a each . The bonus is that I acquired 120V "switched" power from inside the VFD controller. I ran that into the junction box and fed power to the 120V to 12V switch unit. Some simple velcro attatches the unit to the side of the box.





From the 120v / 12V switch I ran 12v DC power to a terminal junction and from there fed 12v DC to the DRO unit and the digital tach. ( Note that the DRO unit uses small magnets to mount nicely to any steel surface)




Overall i'm really happy with the clean install of all the components. I'm not gonna lie this was a HUGE amount of work and forethought but in the end I got a WAY more powerfull lathe, a DRO and a tach setup all with only one 120V plug required.

 

[Road_Clam]

Here's a few pics of how I mounted the Tach sensor . I machined a .500" dia counterbore in the pulley and JB welded the magnet into the counterbore.



Then basically built a bracket system that uses the belt guard bolting bracket as a mounting point