Speed Control For SX3 ?

[cornbinder23]

There is one other thing I have been wondering about with the SX3s - it seems the head spindle bearings are different in some way to the X3s - if I was to jack up the speed, I'd be inclined to swap out the bearings. Anyone have a link with a procedure and/or P/Ns for this ?

Lewis

The lower spindle bearing# is 32907 which I found at EB Atmus, the upper bearing# is 32006, which i found on ebay, and the bearing that sits in the upper pulley housing is a 6006 IIRC

Do a search for spindle bearing replacements here in the benchtop section

JTCUSTOMS

[LewisCobb]

The lower spindle bearing# is 32907 which I found at EB Atmus, the upper bearing# is 32006, which i found on ebay, and the bearing that sits in the upper pulley housing is a 6006 IIRC

Do a search for spindle bearing replacements here in the benchtop section

JTCUSTOMS

Yes indeed, the search function is your friend. I used a different set of phrases this time and found a few detailed threads on this - but from what I found there's a general consensus that "if it ain't broke don't fix it" - still, I'd like to have this information for reference. I'm not sure it's a job for a rank beginner like myself, but I do have a few machinists I know that I can badger if needed.

I'm still plodding my way through all the links that this thread has revealed, but I'm starting to feel that the SX3 is the one to choose between the X3/SX3 - even if I do move to CNC it after a bit of time with it.

Thanks again for the assistance.

Lewis

[cornbinder23]

All in all it was not difficult at all, replacing the stock bearings made a big difference in surface finish, and spindle temperature was lowered as well
A great upgrade in my opinion

I personally did not like the look of the motor hanging off the side of the X3 head, the SX3 spindle motor is a nice and tidy looking machine (unlike the behemoth that sits atop my SX3 now) and the power output was great
I tried stalling the spindle with my hands at several different speeds and I couldnt, and you could hear and feel it compensating the rpm for the torque output

Good luck

JTCUSTOMS

[devers6]

This has been an exercise in frustration for me over the years I have owned my Grizzly SX3 - there have been many false starts for solutions to spindle and speed control. So the info that Al_The_Man provided earlier in this thread came as welcome news that perhaps using a different off-the-shelf driver would be a viable alternative.

I found an AMC B25A20AC drive on Ebay and bought it - should arrive in a week or so. In the meantime, I have begun to collect wiring information from the Grizzly docs. Here is a diagram showing the hookups to the current motor - I would be interested in any advice on how the AMC should be connected to replace it.

Looks like I will be the guinea pig on this - I have already reached out to Al_The_Man via PM, and he has given me some very helpful starting advice. I will log my results in this thread as I see what happens.

[Al_The_Man]

In the mean time you could look at one of the hall sensors with a meter or scope and turning the motor shaft, count how many time is goes high in one revolution, this will tell you the pole count. Just out of interest.
Disconnect the stator first.
Al.

[Crevice Reamer]

This has been an exercise in frustration for me over the years I have owned my Grizzly SX3 - there have been many false starts for solutions to spindle and speed control. So the info that Al_The_Man provided earlier in this thread came as welcome news that perhaps using a different off-the-shelf driver would be a viable alternative.

I found an AMC B25A20AC drive on Ebay and bought it - should arrive in a week or so. In the meantime, I have begun to collect wiring information from the Grizzly docs. Here is a diagram showing the hookups to the current motor - I would be interested in any advice on how the AMC should be connected to replace it.

Looks like I will be the guinea pig on this - I have already reached out to Al_The_Man via PM, and he has given me some very helpful starting advice. I will log my results in this thread as I see what happens.

Cool! Good luck!

CR.

[LewisCobb]

This has been an exercise in frustration for me over the years I have owned my Grizzly SX3 - there have been many false starts for solutions to spindle and speed control. So the info that Al_The_Man provided earlier in this thread came as welcome news that perhaps using a different off-the-shelf driver would be a viable alternative.

I found an AMC B25A20AC drive on Ebay and bought it - should arrive in a week or so. In the meantime, I have begun to collect wiring information from the Grizzly docs. Here is a diagram showing the hookups to the current motor - I would be interested in any advice on how the AMC should be connected to replace it.

Looks like I will be the guinea pig on this - I have already reached out to Al_The_Man via PM, and he has given me some very helpful starting advice. I will log my results in this thread as I see what happens.

Sounds great. I saw a couple of them on ebay as well, but figured I'd just hold off seeing as I don't even have the mill yet !

Please post all your findings in this thread as I am sure there are more than just the 2 of us that are interested in this.

Best Regards,

Lewis

[No1_sonuk]

Is it just on/off computer control you want? While it has digital inhibit, it looks to me like the speed control on that drive is a manual potentiometer input.

[Al_The_Man]

Is it just on/off computer control you want? While it has digital inhibit, it looks to me like the speed control on that drive is a manual potentiometer input.

They are principally servo controllers so they also accept any ±10vdc analogue controller signal.
If you want bi-direction control from a single ended source similar to VFD with FWD/REV then it may take a little outboard logic to achieve it.
I have been using these drives for around 20Yrs so I am fairly familiar with them albeit mostly in the servo usage.
As I also mentioned they are just as adept as DC brushed controllers, although there is also a DC brushed version.
I am willing to work with devers to try and make it work!.
Al.

[cornbinder23]

Is it just on/off computer control you want? While it has digital inhibit, it looks to me like the speed control on that drive is a manual potentiometer input.

This controller does not have a speed potentiometer speed changes are handled through button presses (cell type buttons), it would probably be alot easier to accomplish this if that were the case, IIRC there is someone here that has already accomplished this with the brushless controller for the SX2 as it uses a potentiometer to control speed changes

JTCUSTOMS

[Al_The_Man]

What or how is the primary intention to control the spindle? Variable or stepped? Manual, Mach, EMC, Kflop?
How is the speed control achieved now?
Al.

[LewisCobb]

They are principally servo controllers so they also accept any ±10vdc analogue controller signal.
If you want bi-direction control from a single ended source similar to VFD with FWD/REV then it may take a little outboard logic to achieve it.
I have been using these drives for around 20Yrs so I am fairly familiar with them albeit mostly in the servo usage.
As I also mentioned they are just as adept as DC brushed controllers, although there is also a DC brushed version.
I am willing to work with devers to try and make it work!.
Al.

Sorry for this very basic question but I am a newbie at all this stuff - is there any situation where you would want to run a mill spindle in reverse ?