Steppers for Converting Sieg X2 to CNC?

[Cret]

I wish I knew more about the maths of this stuff currently but it'll come in due course I'm sure.

In the meantime though, I think I spotted something of a bargain that might be perfect for what I need for the X2 to get started, with 3 options I'm pondering on. Yes I was going to try on the dirt cheap with the steppers I've got but these kits are cheaper than I thought, and viglink sent me a few £ earlier today that helps so I'm thinking it may be best to just get a kit with all the bits needed from the outset.

I found this first kit for £110 inc 3x 270oz steppers, driver board, and PSU delivered.
The 270oz steppers should be ok from what I've seen but I'm not hugely keen on the single combined driver board & how good it'd be. Plus I don't know if 270 is enough for my Z axis. I do have an air ram fitted so I'm guessing so but still....
�Free SHIP】 3 Axis Nema23 Stepper Motor 270oz in 3A 4LEADS 3Axis Board CNC | eBay

So more realistically there are these two:

3x 435oz steppers, 3x driver boards, breakout board & 2x PSUs - $299
�Germany SHIP】3 Axis NEMA 23 Stepper Motor 435oz in Single Shaft 4LEADS CNC | eBay

3x 425oz steppers, 3x drivers, breakout board & psu - $319
�Promotion】3 Axis NEMA 23 Stepper Motor 425oz in 112mm 3A Driver DM542A CNC | eBay

Wanted to do it cheap (in my nature) but these kits look great value and I'm thinking I should bite the bullet here.
What I'm curious about is why the kit with the higher power steppers (435 over 425oz) is cheaper and includes 2x PSUs instead of a single one in the dearer kit. Have I missed something?!

Appreciate comments on these - they look just the ticket and am VERY tempted, but don't want to be rash. Not too rash anyway...

[Jonathan]

I wish I knew more about the maths of this stuff currently but it'll come in due course I'm sure.

Have you spotted Irving's spreadsheet, here? If you want the maths, then there's I post I made about it a few years ago here.

In the meantime though, I think I spotted something of a bargain that might be perfect for what I need for the X2 to get started, with 3 options I'm pondering on. Yes I was going to try on the dirt cheap with the steppers I've got but these kits are cheaper than I thought, and viglink sent me a few £ earlier today that helps so I'm thinking it may be best to just get a kit with all the bits needed from the outset.

Keep an eye on the inductance of the motors you're looking at - one of them is pretty reasonable. These motors from CNC4You have good specifications (I've measured them) and a good price, but I strongly advise you to try using Irving's spreadsheet (or my script here, with a few tweaks) to get a better estimate of what size motors you require. The slides and leadscrews on an X2 will exhibit quite a lot of friction (compared to linear guides and ballscrews), so if comparing with other milling machine conversions bear in mind that you'll need bigger motors (to get the same feedrate) if you decide not to use ballscrews.

[irving2008]

I wish I knew more about the maths of this stuff currently but it'll come in due course I'm sure.

In the meantime though, I think I spotted something of a bargain that might be perfect for what I need for the X2 to get started, with 3 options I'm pondering on. Yes I was going to try on the dirt cheap with the steppers I've got but these kits are cheaper than I thought, and viglink sent me a few £ earlier today that helps so I'm thinking it may be best to just get a kit with all the bits needed from the outset.

I found this first kit for £110 inc 3x 270oz steppers, driver board, and PSU delivered.
The 270oz steppers should be ok from what I've seen but I'm not hugely keen on the single combined driver board & how good it'd be. Plus I don't know if 270 is enough for my Z axis. I do have an air ram fitted so I'm guessing so but still....
�Free SHIP】 3 Axis Nema23 Stepper Motor 270oz in 3A 4LEADS 3Axis Board CNC | eBay

So more realistically there are these two:

3x 435oz steppers, 3x driver boards, breakout board & 2x PSUs - $299
�Germany SHIP】3 Axis NEMA 23 Stepper Motor 435oz in Single Shaft 4LEADS CNC | eBay

3x 425oz steppers, 3x drivers, breakout board & psu - $319
�Promotion】3 Axis NEMA 23 Stepper Motor 425oz in 112mm 3A Driver DM542A CNC | eBay

Wanted to do it cheap (in my nature) but these kits look great value and I'm thinking I should bite the bullet here.
What I'm curious about is why the kit with the higher power steppers (435 over 425oz) is cheaper and includes 2x PSUs instead of a single one in the dearer kit. Have I missed something?!

Appreciate comments on these - they look just the ticket and am VERY tempted, but don't want to be rash. Not too rash anyway...

Don't touch last one, 9mH motors are not great, needs to run on 80v+ drivers.
First one is poor, single board and only 24v

Second one is best of bunch, uses reasonable steppers @3.8mH, but these ideally want 4.2A and the drives only give 3A RMS, 4.2A peak. Also PSU is only 36v. Not sure how you use 2 psu across 3 drives; you can parallel up PSUs, but not generally a good idea.

[Cret]

On another note - looks like someone already started doing 3D printer produced stepper mounts:
Stepper Motor Mount Nema23 for Homemade CNC Router | eBay

So will see if I can find design files somewhere....

[Jonathan]

On another note - looks like someone already started doing 3D printer produced stepper mounts:
Stepper Motor Mount Nema23 for Homemade CNC Router | eBay

So will see if I can find design files somewhere....

Flimsy. You have a milling machine - use it.