Stepper motor noise question SOLVED

So, my machine quit moving in X, stepper emitting a high pitched squeal.

Since I had a spare motor I slapped it in.

No movement and same squeal, bummer.

Swapped board connectors, Y right with X. Noise went away, steppers operated. Swapped connectors to proper connectors, powered on SO3, no noise, operation ok.

Began air cut test after homing etc, after about a minute and a half X stepper began to squeal and stopped moving. Y and Z movement ok.

Question: is this an issue with the board? Or?

2/13/19. After days of troubleshooting the cause was, ahem, corrosion on the male pins on the Molex connector mounted on the SO3 board. This caused intermittent faults with whatever motor connector I swapped.
I know, corrosion, what…how…huh? Wish I’d taken a picture before I cleaned ‘em up.

I was thinking it was a driver problem but kept coming back to SMT packages don’t typically fail intermittently. They work or don’t work, in my limited experience anyway.

SO, STEPPER PROBLEMS? CHECK ALL YOUR MOLEX CONNECTORS FIRST. Kinda like making sure the tool is plugged in before you start replacing parts. Duh :roll_eyes:


If there isn’t a wiring extension involved, then yes. If you have a wiring extension it can cause this problem as well.

Wiring is as provided with my XL upgrade. It’s been running fine for the 2 years (?) since the upgrade.

I’m now aircutting a different file. It took longer but same problem after 21 minutes.

1 Like

Usually if the problem arises after a period of usage it’s the wiring extension losing continuity when bent in a certain way.

Contact us at and we’ll do our best to help.

1 Like

Hmmmm, loss of continuity, seriously?

Google, here I come.

Maybe because of constant flexing as X traverses back and forth, stresses the wiring somehow? Had the Molex connector on X fail a few months ago. Will revisit the solder repair. Maybe replace the wiring with some nice flexible silicon jacketed wire.

The molex connectors being used really aren’t intended for this application… the wiring will be susceptible to breaking at the solder joints (and within about an inch of them)


Most likely. I’ll be rewireing, no solder joints in the bendy bits.


I like the idea of rewiring with silicone jacketed stuff. The connectors in the drag chains never felt right to me, and I recently had some issues with the drag chain catching on the x axis. I wonder if I can and afford to go with smaller drag chain with no connectors and silicone jacket.

In anticipation of possible future upgrades I’m going with a Larger drag chain,
40.55" Black Cable Wire Carrier Drag Chain Nested 18mm x 50mm
Will be adding a tray on top of the X extrusion to accommodate the extra width.

Disclaimer: I am not an electrical engineer
This looks to be good wire for our application? Looks like it’s only available in bulk 100’ or 500’

1 Like

Not a good option. It’s not shielded.

The community has notes on wiring at: and you should be able to get something suitable by the foot at your local home center or hardware store.

1 Like

I don’t understand your reference to shielding. The original cable is 4 conductors in a grey jacket, no shielding I can see. I’d guess the black wire is the ground/“shield” wire referred to in the Wiki? Certainly the leads from the steppers with the Molex connectors are not shielded.

When I think of shielded wire I think TV coax.

This is what I’ll be using, just waiting for 2 more colors.

While I wait for new wiring I’ve cut out the soldered connections and re-soldered. Still have a non motivated but singing X stepper motor. :rage: NUTS!

EDIT: I just swapped X and Y connectors, now the Y motor is singing and not moving. Seems like a board problem to me.

Oh. I didn’t realize that the wiring extensions we’re using don’t have shielding — I came across the shielded wire linked from the wiki and assumed that that was what was being used.

They make a shielded version. Can’t find link again on my phone. Will update link later. The idea is that they are rated for constant flexing. On the order of millions of cycles. I don’t think Home Depot had anything like that.

@Griff Sounds like you might have had a driver go on you. Ugh… frustrating!
I wish they’d make the drivers replaceable. Maybe an opportunity to upgrade to discreet drivers, bigger motors and a beefier PSU?

@neilferreri. Sounds interesting but haven’t a clue as to how to go about that sort of complex upgrade.
Pretty spendy I bet.

I can get a new C3D board for 135.

I hear CNC xPro v4 is a nice board for $149. Has onboard steppers plus breakout for external stepper drivers later on.

But anything other than the C3D controller isn’t going to be completely plug’n play.

I knew I wanted to eventually upgrade, so when I blew my board was hard to justify getting the C3D board when I wanted to get something down the road anyhow. It will cost more, a little or a lot depending on the road you go, and getting back up and running will take some time too.

I ended up using this for 9 foot extensions on all my stepper and switch cables:

Reasonably priced, and a length that didn’t require storing a whole spool… Shielded wire does tend to be quite a bit more expensive than unshielded, and a lot more stiff.


Researching this option. I’m considering powering it from the same 24 volt power supply I use for my brushless Makita. Bad idea?

What the hell…trigger pulled on @DanStory and @mikep suggestions.

Guess I’ll start noodling how to remote the controller, power supply etc.