Stepper Power to Resolution Ratio

I want to get a new set of better steppers at some point but I want to be able to use them to full potential even if I never push it there.

If you dont want to change PSU voltage or stepper drivers you may want to source low inductance steppers. But IMO if you want a serious upgrade you need to consider higher voltage systems. This will most likely require different drivers. The current motors will have a new life with stronger drive chain.

I plan on building a new machine for a friend of mine out of all my old parts. So ill probably source new steppers and controller/power. So im going to begin my research soon for what i still need to order for him and the costs involved, plus the cost for me for my new upgrades,and if i can even handle setting it up.

The typical Nema23 140/270 oz motors we use are of higher inductance (mH-number)
Higher mH => higher voltage required to push them into their optimum power/speed range.

The math is:
mH squared * 32 = voltage

So for a 5,6mH stepper:
5,6SQ * 32 = 75VDC

so i would need to pump in more voltage than the current system can handle. (electronics are my weak point, im looking to improve though.)

In all honesty I love your humor. :heart_eyes:
Do you have a parts list for the demon controller?

You are confident with 4000mm/min and 200mm in accl. at the moment - this is with 24VDC.
That is your baseline.
This combination provide you x-torque

If you double the voltage you get the same x-torque but now at 8000mm/min.

Choosing a bigger stepper (270oz instead of 140oz for instance) you now get y-torque, but no change in speed (4000)

To get both torque and speed you would want higher voltage which may quickly require different stepper drivers.

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I know I keep asking but I have less than no idea. Can I put in a better power supply? Or would going with the demon give me better results?
I would like to do 1/4 stepping with more power.

Depend on the hardware.

If Xcontroller is your Status Quo then a Demon is all practical terms equal.
If SQ is ghield a Demon will be a world of difference.
If you go with a Super Demon (say 48V PSU and Leadshine DM556’s) there is a 2nd world of difference…

If you were to go Demon or SuperDemon the power available will bend your ACME if motion is stalled :wink:

My “Demon” consist of 5 items only, one Arduino UNO and 4 external drivers, that is technically all you need. (not counting PSU and the mechanics)

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I must have misunderstood you. But still enjoyed a good laugh. I’m not looking to make acme pretzels but I do want to push some limits.
I have the old gshield and an Xcontroller.
What do I still need?
Main components list:

· (4) TB6600 drives (Approx. $15 each)

· (1) Arduino Uno Rev 3 (Approx. $30)

· 24 VDC 16 amp Power Supply (I used the Inventables power supply)?

· (1) Adafruit Proto Screw Shield (Approx. $15)?

· (5) 12 Position Barrier Strips W/ Jumpers (Approx. $12)

· (3) 0.47uF Capacitors for Limit Switch Noise Filter

· Lots of 18 awg stranded (22 awg will probably work for the signal only connections)

· 2 lengths of 12-14 awg stranded for main power to the drivers

· Wire Duct or Some Form Of Wire Management

· 24 VDC Fans or 12 VDC W/ a Step Down Transformer

And will this setup work with either motor?

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The entire top? Or I can reuse the uno?

Awesome. Any suggestions to source these parts from? (Yes I’m being lazy, and in middle of work. :shushing_face:)
Source is fine. Links are better. :kissing_heart:


Aideepen Proto Screw Shield Assembled Terminal Point Prototype Expansion Board Opening Source Reset Button PCB Bareboard D13 Universal LED for Arduino

MYSWEETY TB6600 4A 9-42V Stepper Motor Driver CNC Controller, Stepper Motor Driver Nema tb6600 Single Axes Hybrid Stepper Motor For CNC

5 Pcs Dual Row 12 Position Screw Terminal Strip 600V 15A + 400V 15A 12 Postions Pre Insulated Terminal Barrier Strip Red /Black 10 Pcs

E-Projects B-0002-D08 Radial Electrolytic Capacitor, 47uF, 50V, 105 C (Pack of 5)

DIYhz green 20PCS 2P 2 Pin Screw Terminal Block Connector 5mm Pitch for Arduino 8A 250V HZ126

@PhilJohnson these ok? I’m not that good with this stuff.

Anything else I should have on hand? I have the old power supply and the old arduino.

No, it’s:

sqrt(inductance in mH) * 32 = optimal voltage

The stock NEMA23s are 2.2 mH, which results in 47.46V optimal voltage. So the stock 24V equates to about half which means, in theory assuming linearity, you’re only getting half of the ideal torque.

The popular 269 oz-in motors are 5.4 mH, resulting in an ideal ~74V operation.

The other option floated around most are 270 oz-in that are 3.6 mH which results in ~61V.

In all honesty, if you want to get better performance- a MX3660 (MX4660 if you want to run a 4th Axis) and dropping GRBL for either LinuxCNC/MachineKit. And if you want to get real fancy PathPilot.

With the MX3660, run it @ 48V and configure the Y Axis driver to 4.05A peak. That’s more than enough to drive dual stepper Ys. As for microstepping I’ve ran up to 1/16 with rack & pinion and lead screws with zero ill effects. As side from running quieter.

The big takeaway is the cheaper drivers are exactly that unfortunately. The TD6600 I was running a couple years back were thermally cutting out. It was doing it at such a random rate it was hard to figure out what/where the issue was. All of those drivers had huge ■■■ heatsinks (which I added) and 120mm fans on them. Once I switch away from the ‘budget’ drivers the now machine sings. Less harmonics more grunt. Quality drivers are the key.

Also VFDs are an awesome upgrade. Watercooled if you can pull it off. (random sidenote)

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basically you need a higher voltage to overcome the magnetic field/back EMF from the stepper to get it to move. That’s why the inductance comes into play as to calculating the optimal drive voltage.

Did you buy this one:

That’s the 269 oz-in that I bought based on your link back last year and it’s listed as 5.4 mH.

Holding torque or rotational torque? Holding won’t be degraded. It’s the rotational that would be.

This is a good site to understand this:

Ok so ideal for yours are 70VDC. Still way higher than the 24VDC the stock uses.

Anyone? GET YOUR CAN OF WORMS HERE!!! For a limited times only, get your can of worms and we’ll even throw in an opener!
But please continue :drooling_face: I’m learning a ton :heart_eyes:.

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