some bondtech upgrade questions

[p-trax]

I have read through the bondtech upgrade thread here, and could not find answers to my specific questions. I hope you guys can help?

I run a single extruder on my N2 dual. I had to purchase a dual extruder set up however.

Q1. Is there a way to disable the second thermo couple on the instrument so that i can remove it from the breakout board?
I have selected single extruder from with the settings menu on the unit, but it still expects the thermocouple to be connected.

Q2. I could not get the VREF to 0.5V, it was either .46V or .56V. I figured that running at just under was better than just over. Is this correct?

Q3. how tight should i screw in the adjuster screw for the filament gear? I havent run any thing through the machine yet (in terms of printing) but it appears to load OK. On that note, I did not need to swap the cables on the extruder motor, it turns in the correct direction.

Q4. has anyone removed the second stepper motor from the dual Bondtech to further reduce the mobile mass?

many thanks

[Vicky@Raise3D]

The forced second thermocouple temperature checking is inside motion board firmware. Only when you using the single-extruder motion board firmware, it will neglect the temperature feedback from the second themocouple. Or no matter you set extruder number as one or two on screen, the motion board firmware always needs to check the temperature of both.

[ABH]

Q1: Just replace the thermocouple with a small piece of wire (10 - 20 mm).

[jetdillo]

How hot should the Bondtech steppers get ? After a 3 to 4 hour print, mine are more than warm to the touch, but not too hot to handle.
I have the pots on the A4988 driver ICs turned down to 0.5V, which was recommended by the Bondtech install docs. I'm wondering if I need them maybe turned back up a bit ?

[Tinkerer]

Q2. I could not get the VREF to 0.5V, it was either .46V or .56V. I figured that running at just under was better than just over. Is this correct?
A: Right, under is better than over.
But: It is a bit tricky and may takes several attempts - but it is possible to get to the 0.5 Volts.

Q3. how tight should i screw in the adjuster screw for the filament gear? I havent run any thing through the machine yet (in terms of printing) but it appears to load OK. On that note, I did not need to swap the cables on the extruder motor, it turns in the correct direction.
A: Without any filament in the extruder, just turn the screw so that it starts to bind against the spring.
When filament is loaded, the spring will be under tension and okay.
I started with way too much force/preload of the spring and learned that this may leads to grinding of the extruder gears into the filament.

Regarding the temperature of the bondtech extruder stepper motors:
Yes, they are getting hot at least for a humans feeling.
I have measured around 55°C after a few hours of printing ABS with the N2 completely closed.
Nothing to worry about, I'd say?

[p-trax]

Thanks for the answers