[cornbinder23]

Now I know I could probably go through the forum and find this info but if any one wants to chime in
What would be the ideal combination?
VFD , 1HP 1720 rpm 3ph
VFD , 1HP 3450 rpm 3ph
any other options?

I want to be able to control my spindle through Mach
My plan was to buy the SX3 just for the better motor, but these other set-ups
would negate the extra cost.
I already have the motors listed above and a VFD from automation direct would be a much cheaper solution
Also how much does the stock motor weigh? are these a little overkill?

[SCzEngrgGroup]

Now I know I could probably go through the forum and find this info but if any one wants to chime in
What would be the ideal combination?
VFD , 1HP 1720 rpm 3ph
VFD , 1HP 3450 rpm 3ph
any other options?

I want to be able to control my spindle through Mach
My plan was to buy the SX3 just for the better motor, but these other set-ups
would negate the extra cost.
I already have the motors listed above and a VFD from automation direct would be a much cheaper solution
Also how much does the stock motor weigh? are these a little overkill?

What kills productivity on these little machines is the ridiculously low stock spindle speed. I'd definitely go for anything that gets the RPMs up, preferably to at least 6K, if not more. You may have to do some work on the spindle bearings to get it to work well at that speed, as the stock ones are often VERY poorly fitted. But, you'd have a FAR more useful machine in the end.

Regards,
Ray L.

[cornbinder23]

these 3 PH motors are alot larger if I remember right from the last time I was at grizzly, than the stock one.
I went with CR's recommendation on the 906Oz nema 34 with the G540
will it still be sufficient for the added size of the three phase motors?

I am hoping these will work as I got them in trade for some custom SS handrails on a friends boat, they were for another project he had,that he never got around to finishing so I got em 2 Baldor 3ph 1hp brand new still wrapped in the factory stretch wrap 1-1725rpm 1-3450rpm

[Quazar]

these 3 PH motors are alot larger if I remember right from the last time I was at grizzly, than the stock one.
I went with CR's recommendation on the 906Oz nema 34 with the G540
will it still be sufficient for the added size of the three phase motors?

I am hoping these will work as I got them in trade for some custom SS handrails on a friends boat, they were for another project he had,that he never got around to finishing so I got em 2 Baldor 3ph 1hp brand new still wrapped in the factory stretch wrap 1-1725rpm 1-3450rpm

The stock motor in a SX3 is rated for 3600 RPM. The timing belt roughly divides this by 2 (it is actually 22:45 if I counted correctly) which results in the 1750 RPM top spindle speed. My plan is to replace the 22 groove pulley on the motor with another 45 groove pulley which will give me a top spindle speed of 3600 RPM (1:1).

As for power, the Grizzly manual claims 1HP. The motor that came in my SX3 is rated at 1KW, which should be about 1.34HP. Assuming the motor is capable of delivering on its plate rating, and that the driver board is capable of driving it close to capacity, I think this should be sufficient for my needs.

That just leaves spindle speed control. I'm working on a board that intercepts the signal from the BLDC motor driver to the front panel controls & tacho. It will monitor the speed relative to the requested speed and adjust by faking button presses. It will also correct the tacho display so that it shows the adjusted (actual) spindle RPM.

If it all goes well, the board will just be an Arduino, which is commonly available for as little as $20. If I can get it going, I'll share the code and wiring diagram for others to enjoy.

Cheers,
- Dean

[cornbinder23]

If I go with either of these larger 3ph motors will I have to counterweight the head or will kelings 906oz stepper on the G540 be sufficient. I know the stepper gets de-tuned w/ the G540 ,but these are too easy not to use, they have just been gathering dust for a month or two now
any one out there with any personal experience with these set-ups
where would be a good place to source the spindle bearings
I will be doing the mill teardown this month and would like to do it all at once
Before the mill goes into its enclosure

[Quazar]

If I go with either of these larger 3ph motors will I have to counterweight the head or will kelings 906oz stepper on the G540 be sufficient. I know the stepper gets de-tuned w/ the G540 ,but these are too easy not to use, they have just been gathering dust for a month or two now
any one out there with any personal experience with these set-ups
where would be a good place to source the spindle bearings
I will be doing the mill teardown this month and would like to do it all at once
Before the mill goes into its enclosure

Just to be clear - you have the X3 and not the SX3, right? I'm converting an SX3, but I'll share my plans in case they are of some limited use to you.

I'm also using the 906oz stepper & G540, and I'm getting the "CreviceReamer" Z pulley option from CNCfusion. I plan to use a gas strut to help offset the head's weight, though that will limit my Z travel a bit.

As for motor weight, my SX3 motor weighs about 12 lbs, but I'm not sure how much an X3 motor weighs. How much do your replacement motors weigh?

As for bearings, I'm looking for a source too. I'm using this thread as a guide.

Cheers,
- Dean

[Crevice Reamer]

....I'm also using the 906oz stepper & G540, and I'm getting the "CreviceReamer" Z pulley option from CNCfusion. I plan to use a gas strut to help offset the head's weight, though that will limit my Z travel a bit.Cheers,
- Dean

Hi Dean.

You should not need any gas strut--The X3 head is heavier than SX3 and Jeff Davis is getting 250 IPM without strut with CR option.

You can make the SX3 head even lighter by removing the quill drive casting and parts.

CR.

[Quazar]

You should not need any gas strut--The X3 head is heavier than SX3 and Jeff Davis is getting 250 IPM without strut with CR option.

I had already installed it from when the machine was non-CNC to reduce operator (me) fatigue. It made a noticeable difference.

Once the CNC conversion is complete, I'll try running it both ways to see if there is a difference. It is easy enough to pop on and off as needed.

You can make the SX3 head even lighter by removing the quill drive casting and parts.

Yep - I've currently got all the quill drive extras removed. The head is stripped down pretty light at this point.

Cheers,
- Dean