Delta SKR 1.4 with TMC2209s, extruder is intermittent running Marlin 2.0.9.3

[rmhorwitz]

I recently got this Delta system up and running. I noticed that some of the linear printed lines were intermittently missing. My extruder is mechanically sound , so no substantial drag except for the smart filament detector which sometimes triggers a blocked filament error. I placed a wrench on the extruder motor shaft and allowed it to turn while monitoring the torque by keeping a very light load on the wrench. During the episodes of no filament extruding, I noticed that the servo motor went limp, as if power was removed momentarily. I swapped out the TMC2209 driver, No change. I increased the current of the servo in configuration. adv to 2000:

if AXIS_IS_TMC(E0)

#define E0_CURRENT      2000
#define E0_MICROSTEPS    16
#define E0_RSENSE         0.11
#define E0_CHAIN_POS     -1
//#define E0_INTERPOLATE true

The only other thing I can think of is:

define DELTA_SEGMENTS_PER_SECOND 200

This didn't yield any improvement. At this point, it is obviously a bug in the Marlin Software and I am open to any suggestions to resolve it.

Any help is greatly appreciated,

Rick

[radek8]

Try to increase the value

define HOLD_MULTIPLIER

or ban it Sets reduction the current during inactive time

[rmhorwitz]

Thank you. I looked at my Pronterface log and noticed a couple entries stating E driver over temperature warnings ( 2000mA) I lowered the current down to 1.6 A. Per your recommendation I attempted to comment out the #define HOLD_MULTIPLIER, but the compiler complained so I raised it from .5 to 1. Sadly, I still have the same problem.

[radek8]

The 1.6A current on the extruder comes to me a lot. I use 700mA and I have no problems. In discussions, I have often seen recommendations for TMC2208 and 2209, to switch the stealthChop mode to spreadCycle for the extruder. // #define STEALTHCHOP_E or via terminal M569 S0 E

[rmhorwitz]

Thank you again. I am currently printing and I entered that change on the fly, but I am still getting the tell tale "Thunk!" from the extruder motor when it restarts turning.

[radek8]

define HOLD_MULTIPLIER

This choice has its meaning. When the motor is not moving, it reduces the current flowing into the motor. A lower current is enough to maintain the position and the motor, together with the TMC controls, does not heat up as much

[radek8]

Thunk???

[radek8]

Can't TMC2209 overheat? 2A is the maximum for him with very good cooling

I would try to swap TMC. If another driver will behave the same.

[rmhorwitz]

Yeah, I thought the device might overheat too, so I reduced it down to 1600, but the same issue. BTW- "Thunk!" is the sound the servo makes when it turns back on. I think I am going to reduce the current down to 700 and see what happens.

[rmhorwitz]

Oh Wow! I read back M906 and it had the old values 2000. I must have forgot to save them from the last reset. I set them down to 1200 and it appears to work!!!! Redak7- you are a genius!!! Thank you so much!!!!!