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Topic: Temperature probe offset

Is there a place to adjust an offset for my temperature probes?

My heated bed seems to consistently be about 10 degrees celius hotter then what the probe is telling the software. Or so says my ir thermometer.

SD2 w/ mods: Rumba controller, ATX PSU, SD pro case, glass bed, with more to come...

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Re: Temperature probe offset

With the solidoodle, it's VERY IMPORTANT not to think that the temperature reading it's giving you is accurate.

It's in fact 20 to 30 degrees hotter at the nozzle than the software reports !!


This is important, because if you throw down "230C" as your target temp, you will be running very hot, and possibly melt your nozzle insulator. 



So I usually print 190-200C, with a first layer 5 degrees above that.  200C only for my crappy filament that doesnt work unless I push the temp limit. 190C is fine for the rest of my filaments.

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Re: Temperature probe offset

Okay, sounds good. Thanks Tomek.
Looks like I'll just manually tweak the temps then to compensate.

Noob question here: Do you do the same for the heated bed? (I.E. - Print the first layer at 90C and then dial it back to 80C for the rest of the print.) So I'd essentially be tweaking the temp for both extruder head & bed for the first layer.

SD2 w/ mods: Rumba controller, ATX PSU, SD pro case, glass bed, with more to come...

4 (edited by Tomek 2012-11-26 04:39:07)

Re: Temperature probe offset

To be honest, I'm not sure about the heat bed.   I believe it is not the case for the heat bed.



The bed I tend to run at 90C, but go as high as 100C when I have a print that I want to stick extra.  I'm going to start using the bed at 80C, though, because quite a few of my recent prints have sticked *too much.*


To answer your other question, in principle I used to do the heated bed at 5 degrees higher temperature for the first layer, but I don't bother with that anymore. The biggest thing for solving my early sticking problems was to make sure the z-home is set fairly close to the nozzle, and that the bed is well leveled (the bed needs to be well leveled in order to keep the z-home close to the nozzle. If it's not, then parts of the bed will be scraping to the nozzle and other parts won't be.) That initial "squash" on the first layer helps everything stick very well. So does using a brim when the object has a particularly thin brim.


Those temperatures are within the ranges other places have described for heated-bed temperatures. So, I think bed temperatures are fairly accurate.