1 Topic by NicoleJS (edited by NicoleJS 2021-08-25 04:20:21)

  • NicoleJS
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Topic: thermistor failure?

I'm still a total noob to 3D printing, but I've managed some good prints..all with pla.....so i figured I'd move on to abs....that's when it hit the fan!!
couldn't get it to stick to the bed...but that's ok, I went thru the forums, changed the bed temps....no better, so I got to tinkering, and discovered a few things...my bed was getting way too hot, but the pronterface was reporting it wasn't hot enough, yet...pulled out my trusty meat thermometer, and discovered the extreme discrepancies between reported and actual temps...so, the question is...how do thermistors fail....do they gradually get out of whack, before they give up the ghost, or is it a works or don't work thing?

afik, it was working correctly with pla...the bed seemed reasonable hot when I set it to 60C, and the prints stuck like glue...until they cooled down a bit, then they released...Sonneries Gratuites
but as soon as I tried to heat the bed to 110C, my troubles started...the thermistor refused to report anything higher than 80 some odd, and it varied...84 sometimes, 79 others...when the bed itself read 120 degrees....new thermistors on order, but until that time...any ideas, any hints...anybody else experienced anything similar?

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2 Reply by Tin Falcon

  • Tin Falcon
  • Tin Falcon
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Re: thermistor failure?

could just be wrong firmware settings.
Tin

Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura

3 Reply by wagnmkr

  • wagnmkr
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Re: thermistor failure?

In the machine's specs, what is the highest bed temp? Some I have seen don't go above 100c.

Also, have you used a separate thermometer to see what the actual temp is?

Just a newbie myself, but that would be where I would look first.

Tom

I was cut out to be rich ... but ... I was sewn up all wrong!
Wanhao Duplicator I3 Plus with glass bed, MK10 All Metal Hot End

4 Reply by Tin Falcon

  • Tin Falcon
  • Tin Falcon
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Re: thermistor failure?

About 6 months ago I tried printing  ngen on my  sd4  used recommended heat setting and the thing just kept shutting down ,turns out i was hitting max set temp. so just turned down the heat IIRC 10 degrees and it worked fine.
try a lower setting on a test print see what happens . Or like mentioned earlier  check your firmware settings.
But before you increase firmware temp limits make sure your hardware can safely do what you are asking it to.

You may also need to change the selected thermisistor in firmware . IIRC you modded a printer to ramps?

Tin

Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura