Lulzbot 747 trouble keeping 210 temp

I have a taz 747 that I am trying to get to print well with the KM settings.

When setting the extruder temp to 210 the printer will heat up to that temp but as filament flows on the first layer it drops to 200 and doesnt really catch up.

Is the fan speed element on the output tab teh extruder fan?

I have set it to 200 from 255 I plan to continue ot set it lower but I want to make sure it is not the cooling fans for the filament.

PS it will hold temp fine with other slicers.

Is it possible you have range settings that adjust the fan speed or nozzle temp? If the gcode says go to a temp and the printer can’t hold it, that’s a printer problem. If the temp swings at different points with KM gcode and not with others, then there is another gcode command in there changing the temp. This is not a bug in KM, but a setting you are overriding somewhere.

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I clipped the filament as it was printing and as soon as it ran out it heated up again. I loaded more filament as it was pringint and it started to bog down again. So I actually think it is a flowrate / speed problem.

I have my KM speeds at below 60 which the printer should handle fine but it seems to be zooming pretty fast.

Is there some way that the KM speeds are being doubled or some multiplier?

For some reason the following code was commented out in my header file:
M92 E420 ;Set Axis Steps-per-unit
M301 P21.0 I1.78 D61.93 ;Set Hotend PID
M906 E960 ;TMC Motor Current

So now uncommented it looks much better.

I’m not a huge fan of putting firmware overrides in gcode headers. It’s so machine specific (two otherwise similar machines may require slightly different firmware settings). I think firmware should be tuned and set once. But if it’s working for you now, great.

Yea I am not experienced enough to have any kind of finesse in setting all this up. I am just poking this with a stick until it works.

With time I am sure all my prodding will come back to haunt me as I gain experience.