Grizzly 4 3/4” Power Rotary table c/w DRO

[Jmccrack]

Hey guys need a little help. This is a new item for Grizzly. It looks interesting. It says it has a 4a drive motor. I cannot find what size stepper motor that is. Does anyone have any experience with this unit or one like it?
Sherline has one that looks close and it is a #23 framestepper motor. I know it is not big but just to index it does not have to be. I thought I might remove the stepper motor and controller and adapt it to my larger rotary table. Thoughts,suggestions?

 

[bmac2]

Hi Jmccrack.

If this is the one it’s a nice looking little unit.

I think there talking about the motor being rated 4 amps, and that makes sense. Looking at the picture it looks like the stepper is a little less than half the size of the table so that would make it a NEMA 23 (56mm / 2.2in.) with a rotary encoder stuck on it’s bum.

 

[Jmccrack]

You bet that’s the one. The brochure says the table is capable of handling 100+ lbs. If that is the case the stepper motor must be able to turn that weight. I just ordered it so we will see. The only problem I have is I cannot find any reviews on the unit. So I guess “you pay your money and you takes your chances”.

 

[Jmccrack]

These stepper motors must have a lot of torque.

 

[Jmccrack]

Hey guys I got the unit today. It is all that was advertised. Workmanship is not bad. The table is flat to the mill bed in the .0002” range. The #23 Nima stepper motor has more torque than I imagined. More than enough to mill with a 1/2” endmill. I am definitely going to put my 6” 3 jaw on it along with a nice size pallet. I am pretty sure the rigidity will bethere.

 

[Wizard69]

Turning 100 pounds should be easy considering the worm gear reduction.

 

[Jmccrack]

You bet. I just took it all apart to drill the table. To my surprise it has bearings thruout. 4” thrust bearing. And center shaft bearings.

 

[Jmccrack]

Well here it is. I took it apart to make sure it was clean inside and it was pretty good. I drilled and tapped the table for a pallet. And I mounted a 6” 3 jaw directly to the table. I had to drill thru a 3 jaw from the top side and it worked well. It’s back together now. No backlash that I can detect.

 

[Wizard69]

Looks nice! Thanks for the picture.

 

[Jmccrack]

So here it is. I mounted a 6” 3 jaw on the 4” table. Runs on the horizontal within .002” . The controller is dead easy to use. I have taken a 90 deg square cut than ran a dial along both faces and it was bang on. I think this might be fun to use.

 

[AzBob]

Jmccrack,
I am considering that same stepper drive rotary table from Grizzly. How is it working out for you to date? Any idea as to the positional accuracy? As you and others have said, it appears to be a fairly robust and well made. Any feedback would be helpful. Not much out there in the way of reviews for this item.


T1191—4-3/8" Power Rotary Table with DRO Control

 

[e.picler]

Hi guys!
I think that motor is not Step motor given that regular Step motors does not have an encoder.
To my knowledge it is a Step Servo motor also known as Hybrid motor or Easy Servo. Compared to Step motor, the Step Servo is more accurate (does not loose steps), has more torque and is more salient and smother movement. It requires a special specific driver, regular step motor drive does not work.

Edi

 

[Jmccrack]

I am away right now. When I get back I will run a series of tests on it and report the results. I know when I did the 90° cuts then ran the dial indicator on them it was dead on.

 

[AzBob]

Jmccrack,
When you are running your series of tests, If you would, please check the runout on the MT2 tapered center bore. Thank you.
Bob

 

[AzBob]

Jmccrack,
Never mind. Looks like you would have to remove the 3 jaw chuck to do the MT2 bore runout check.

 

[Jmccrack]

No problem. I did that right after I got it before I dissaem

 

[Jmccrack]

Sorry about that. I did check the runout on the taper before I disassembled it. It was less than .0002” run out

 

[AzBob]

Thanks for the info Jmccrack! .0002" is pretty good.

Just checked the MT2 bore on my manual 6” rotary table. It has .0004” runout.

 

[Jmccrack]

I like the ability to machine with it. I set it on speed 1 and can machine quite nicely

 

[tjwal]

Hi guys!
I think that motor is not Step motor given that regular Step motors does not have an encoder.
To my knowledge it is a Step Servo motor also known as Hybrid motor or Easy Servo. Compared to Step motor, the Step Servo is more accurate (does not loose steps), has more torque and is more salient and smother movement. It requires a special specific driver, regular step motor drive does not work.

Edi

The parts manual lists it as as having 2N-m (284 oz-in) torque. It doesn’t show the encoder at all. From what I found it is a stepper with a 1000 lines/rev encoder. It can be run as a stepper with a normal stepper driver or with a special driver it operates more like a servo and you get the advantages you list.