Question about a couple of perceived differences between my two UM2 machines

[chrisw 70]

One of my systems is 1.5 years old, the other is .5. The settings and hardware are all the same to the best of my knowledge, but they act different from each other in a couple of ways.

Both systems use: Robert feeder, Olsson Block with .6 nozzle, GR5's 35W heater, and the Ultitop cover/door.

Difference #1: The newer UM2 shows approx 10C less nozzle temp in the control panel to get the same results from the same materials. This 10C difference has been the same for the stock heaters and the upgrades. It's not a big deal, but if it's possible to make them read the same it'd be nice.

Difference #2: The feeder motor on the newer machine seems to "chirp" or skip a step as soon as there's any strain being put on it. However the feeder motor on my older machine seems to chug right along, pushing filament through stronger, only skipping a step if I'm pushing it hard. Could there be anything making these two feeder motors behave differently?

These aren't really issues, because both systems are providing great print results. Just a couple questions I've been wondering about for a while.

[Labern 774]

The PT100's can be very different from one to another. This is the reason why it has been improved in the UM2+

If I remember correctly, Gr5 test's his before he sends them out. So either social a UM2+ sensors or 2 tested ones from Gr5 may help with consistency.

Not sure about the feeder. Maybe bowden tube? Alignment issue with heater block?

[cloakfiend 995]

I had similar issues, although i noticed minor upgrades on my current um2 to the older one i had, like a white bit in the feeder to guide the filament a touch better, a nozzle guard also (which irritated me) and i also got a spare hotend kit( bonus!) , which i needed when i broke my pt100 heat sensor. After replacing it with an offical stock replacement, i noticed my temps also change, it may have been the ob, but who knows. The feeder clicked like my old one, i read before about the diamond grips gripping better if the were positioned a certain way.

Edited February 20, 2016 by Guest

[chrisw 70]

Thanks @Labern. The Pt100 could definitely explain the 10C heat reading differences. I have a spare here, so I'll try mixing and matching to see if I have a similar pair. If not then I'll go to GR5

Regarding the feeder, maybe the bowden tubes are different. I'll try swapping those and see if the chirps follow the same tube to it's new home.

[chrisw 70]

 

@Cloakfiend : Thanks for the reply. I don't think I've ever seen a white bit in the feeder tube. I'll see if I can locate a description of that around here somewhere

[neotko 1,417]

Quick idea, maybe one of the ultimakers has a newer firmware? Latest firmware on um2 did change the amps to the feeder motor. That can change the force.

[ultiarjan 1,223]

Quick idea, maybe one of the ultimakers has a newer firmware? Latest firmware on um2 did change the amps to the feeder motor. That can change the force.

 

And if you use simplify3d as a slicer in the default UM2 setting the start G-code will change the motor current, which can also cause a difference.

Think the default is 1250 atm, S3D sets it to 1400, probably fine as long as you are not living in the hotter parts of the world where the extra heat from the feeder motor will be enough to be past onto the filament, causing melting/grinding.