One rumbling stepper

[CDRELXIV]

Hi all,
I've just about finished a large upgrade to my V2. 24V PSU, Duet electronics, dampeners on the tower steppers, my own belt tensioning arrangement, e3d V6 and so on. The Duet and or the stepper dampeners have done an amazing job bringing down the mechanical noise. By far the loudest component now is the little hot end fan on the e3D V6. That is one annoying fan.

I have one tower stepper that still makes much more noise than the other two, it did this before the upgrade as well. I have tried altering the belt tension and checking how the stepper is mounted, but it's still the odd one out. It doesn't sound like it's in any danger, just whine/rumbles when it moves fast. Any ideas what could cause that?

Here is my belt tensioning arrangement, I don't think it's a cause of the noise, I just wanted to share it because it's the one original part of my upgrade
[img]http://i64.tinypic.com/2e1d1t2.jpg[/img]

[DeltaCon]

NIce and simple tension mechanism. Have thought of this before but was never able to find the right vertical screws. Where did you find them?

[CDRELXIV]

eBay, via China, the usual

I used metric, M5 SS for the eyebolts running vertically, M3 for the horizontal "axle". M3.5 would have been the closest metric match for the imperial dimension bolt used in the original V2 idlers/bearing.

Here are the product links:

http://www.ebay.com.au/itm/252592783055 ... EBIDX%3AIT

http://www.ebay.com.au/itm/351608568394 ... EBIDX%3AIT

http://www.ebay.com.au/itm/351886740126 ... EBIDX%3AIT

http://www.ebay.com.au/itm/351886741280 ... EBIDX%3AIT

[Ravitch]

Have you tried swapping it out with another to see if it's an internal problem with that specific stepper?

[CDRELXIV]

No spares on hand It's not a big deal, just became more noticeable recently.

[Jimustanguitar]

I've got a machine with a Duet that has a "sticky" tower as well. In my case, I think that the issue is the belt idlers grabbing the sides of the belt and working like a bicycle brake on it... I designed the plastic pieces that hold the belt idler in place, and got a little over eager with the tolerance...

Anyway, all that to say, I'd make sure that your tensioners aren't holding the idler at an angle or causing the belt to contact the plastic bearing holder at all.

[CDRELXIV]

Thanks, I tried to make sure the idlers were parallel by moving each carriage up and down and making sure the belt stayed approximately in the centre of the idler. The wingnut tensioning was great for that because it let me lift one side of the idler by a tiny amount until it was right.

The noise is hard to isolate, maybe I'll take a look at the carriage bearings and see if one is a little off-shape.