Maximum working temperature?  

Re: Maximum working temperature?

There are a few temperatures you need to consider and they will mostly depend on your ambient.

The electronics have to be considered but probably more important is the filament temperature. The filament needs to be cool enough to feed properly and in an enclosure you have the enclosure temp to take into account plus the heat from the extruder stepper heating up the spindle and drive pulley. If the drive pulley exceeds the GTT of the filament, then it will dig into the filament and your extrusion will become inconsistent.

Peter

Re: Maximum working temperature?

Since I have access to thermal imaging camera, I'm going to check filament temperature at extruder gear under my normal ambient conditions. This should give us some rough estimation.

What is max recommended operating temperature for PSU & RAMBO? I am aware that they can be mounted outside of enclosure, but that severly limits mobility of the device.

Re: Maximum working temperature?

With ambient temperature of 26.0'C, nozzle at 255'C (and heatbed at 100'C, which should be irrelevant), I have measured filament temperature inside extruder as 29.4'C at most. Even taking into account inaccuracy of this type of IR imaging, filament temperature in extruder should be non-issue.

Re: Maximum working temperature?

With ambient temperature of 26.0'C, nozzle at 255'C (and heatbed at 100'C, which should be irrelevant), I have measured filament temperature inside extruder as 29.4'C at most. Even taking into account inaccuracy of this type of IR imaging, filament temperature in extruder should be non-issue.

Is this after a few hours printing in high power mode?

Peter

Re: Maximum working temperature?

Is this after a few hours printing in high power mode?
No, this is beginning of a print in silent mode. Nozzle was, of course, at working temperature. You make a fair point, I will make another test at end of this print. Here is mid-print situation:

Ambient temperature is now 26.9'C. This is 1:20 of the print.

I was led to believe that high power mode changes only current supplied to steppers, they should have little impact on filament temperature. Why do you believe it will have an impact? I can of course make another test in high-power mode - i still have lots of things to print.

Also, do you have any data on allowed operating temperature of PSU & RAMBO?

Re: Maximum working temperature?

For me I did a 12 hour print with ABS, nozzle temp 250C heatbed 110C. My enclosure got to 46.5c sometimes hit 47c. The rambo Bix measured 60c. Didn't notice any issue. I did notice some pla filament I had on a spool droop

Re: Maximum working temperature?

Didn't notice any issue. I did notice some pla filament I had on a spool droop
It might be a good idea to mount filament outside of enclosure, or in separate (ventilated) box. I initially thought that keeping spools inside enclosure would be beneficial, as they should get de-moisturized for free.

Does your enclosure help significantly with ABS prints? I have some large (as in: near build area) ABS prints on queue and I'm thinking of building enclosure specifically for them.

Re: Maximum working temperature?

Humidity inside enclosure is only 15% when I start printing. I've never printed abs outside enclosure. But it did take me a while to find the right settings to get decent prints. I've not had any warpping so far I have printed some large piece

Re: Maximum working temperature?

As an update, this is after another 1:10 of print, tuned into in high-power mode:

Ambient temperature right now is 26.4'C

Re: Maximum working temperature?

I was led to believe that high power mode changes only current supplied to steppers, they should have little impact on filament temperature. Why do you believe it will have an impact?

The filament is driven by a stepper motor, which passes its generated heat through both its casing and spindle, the latter connects to a brass (or maybe steel - it used to be brass) filament drive pulley which is constantly in contact with the filament. The extruder motor current is about 450mA in "silent" mode and 500mA in "high-power"mode.

Peter

Re: Maximum working temperature?

The filament is driven by a stepper motor, which passes its generated heat through both its casing and spindle, the latter connects to a brass (or maybe steel - it used to be brass) filament drive pulley which is constantly in contact with the filament.
Fair enough. Here is thermal image of extruder after 1:30 of printing in high-power mode:

Re: Maximum working temperature?

So, assuming the FLIR is set OK, that's 20 degrees above ambient.

When running in an enclosure at 45 degrees, the extruder could be above GTT of PLA and some other plastics, so enclosure temp should not exceed 40 degrees.

And that is assuming the extruder motor is run at around 500mA which can be increased (in the MM upgrade) to 750mA (and the motors can get very hot).

Peter

Re: Maximum working temperature?

Well it does make sense to have optional airflow for printing PLA anyway, since you want to cool down your part. For ABS and PC this should be non-issue, right?

Re: Maximum working temperature?

Well it does make sense to have optional airflow for printing PLA anyway, since you want to cool down your part. For ABS and PC this should be non-issue, right?

Yeah, they are both GTT > 100 degrees so with the single extruder, should not be too much of an issue.

Peter

Re: Maximum working temperature?

For some info in my enclosure my temps are:
ABS Nozzle 250C, Bed 110C enclosure temp max about 47C
PLA Nozzle 205C, Bed 55C enclosure temp max about 37C