Want to replace a stepper motor, how powerful can I get before needing a stepper driver?

Hardware Installation
#1

Machine:Chinese Blue and White 600x900

Board: Laser Board

Firmware: Not entirely sure? Whatever the default is

I want to upgrade my X-Axis stepper motor to something with more torque as it randomly locks up and ruins my engrave as well as the material. The head and belt tension seems SUPER sensitive that even a light breeze or slight touch locks my current one up briefly, even when nothing seems to happen. It doesn’t grind the belt (indicating a loose belt), it makes a weird noise and stops working, and when it resumes it will be in a different location because the program continues to run in the background if that makes sense creating a layer shift. And tightening the belt makes it happen WAY more frequently, so I try and find a balance where it only happens occasionally.

The one I have right now is this one: https://core-electronics.com.au/stepper-motor-68-oz-in-400-steps-rev.html
It’s 1.7 amps, but I’m wondering what my limit on upgrading it is until I have to install an external driver? I bought a driver when I bought the laserboard, but it seems like a big job to install that and I’m wondering if maybe I can upgrade it to a 2 or 2.1amp motor and it might still be able to run without a driver? I feel like 3 amps may be over the line…
I’m looking at this motor in particular right now:
https://www.ebay.com.au/itm/High-Torque-Nema-17-Stepper-Motor-65Ncm-92oz-in-2-1A-DIY-CNC-3D-Printer-Extruder/171823945769?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
But I have also been looking at some Nema 23 3amp stepper motors (though I imagine I’d need a stepper driver for that)

I guess my question is, how many amps can I add until I need to upgrade to the external driver?

I’m not sure if it’s related, but I have a powered Z-axis motor that was there before the laserboard and it still works, but every time I use it and RELEASE the button to go up or down, it disconnects the laser from my laptop for a split seconds as if the power cut out briefly or something. To re-iterate, if I move the bed up, I press the button and it moves up fine and normal. As soon as I LET GO of the button, my laptop makes the noise of a disconnecting USB device and the head of the laser re-homes like it has been reset.

I hope that all made sense, I’d appreciate any help!

Regards,
Soren

#2

My first question is, have you increased the amp output on the config file? When I got mine it was set to .4a. I have lots of missed steps and stalling. I increased mine to 1.5a, and it has worked great ever since.

Ray

#3

Just an FYI the LaserBoard is capped at 1.2A.

#4

thanks for the info, I may change mine in the future if I get the card out again

#5

What would you change?

#6

From 1.5a to 1.2a on both motors

#7

So basically you are saying I have a 1.7A stepper motor, but it is only running at .4 amps? And is that capped at 1.2A per motor, or for the whole system?

#8

I have not! Great tip, I didn’t realise it was being capped in the software! I’ll try that out now

#9

Capped at 1.2A per driver.

#10