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Topic: Extruder Safety Issue

My last hot end cooked itself when I was running my Solidoodle 2.

I think my melt down occurred because the extruder always goes past the 195 default temperature when it is warming up.  This is due to the fact that the temperature Ramp Rate is too high, and because the Start Temp is too high!

It always seems to reach about 202 degrees C when I start printing. 

To try to fix it, I set the "set extruder temp" custom G Code to 190 in Slicer.  I also set the first layer temperature to 190 in Slicer. I even set the default extruder temperature in Repetier to 190.

No matter what settings I change, my extruder always ramps up to a target of 195, and then glides past it to about 202 C.

Is this mysterious 195 C starting temperature embedded in the Solidoodles Firmware?????????

Where the heck is the warm up temperature ramp rate located too???????

I think this is a safty issue if Solidoodles are being shiped with this "unchangable" (via software GUI) ramp rate and default temp set the way they are.  I think the max hot end temperature is like 210 C, right? Thats way too close for comfort since I'm always reaching 202 +/-2 degrees C....

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Re: Extruder Safety Issue

1.) it's not a safety issue, there's no danger to your health by it running at 195C, so your title is misleading.
2.) nothing is hard coded. You're missing a setting, probably in your slicer of choice.

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Re: Extruder Safety Issue

Oh-and there's no ramp rate - why do you want one?

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Re: Extruder Safety Issue

Search around here for PID Autotune and see if that helps the overshoot.  The 195 temp may be in the start gcode.

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Re: Extruder Safety Issue

Thanks Ian!

6 (edited by danny 2013-05-02 11:23:39)

Re: Extruder Safety Issue

what print software are you using?

weirdly I find that if I use repetier host then the hot end heats up and stays where it's meant to be with no overshoot.

if I use printerface then overshoot is easily visible on the graph for monitoring the temperature. also if my hot end is set to be near the top limit I can find that it overshoots mid print and messes up the print as the printer wants to be reset before if would carry on printing.


(obviously that's weird because it's not controlled directly from the printing software pid vs bangbang)

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Re: Extruder Safety Issue

elmoret wrote:

2.) nothing is hard coded. You're missing a setting, probably in your slicer of choice.

I'm having a weird issue.  I have everything that I can find set to print with the extruder at 195 (including the start G-Code).  Whenever I start a job, it runs the G Code, sets the temp to 195, then when it starts printing the first layer, the temp setpoint in Manual Control goes to 200.  Any thoughts on what might be changing the temp?

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Re: Extruder Safety Issue

Not to jack the thread, but I have a related issue.  On my SD3 I'm running RH and Slicer.  Haven't used any other program to slice with yet...  Anyway, all of my Slicer settings are set to raise my extruder's temp to 195.  Also, my manual setting is set to 195 and I have verified in  the Gcode that the temp is set to 195, but when I click run my temp set point at the bottom of the screen, for the extruder is changed to 200.  The printer will not begin printing until it reaches that point. 

Also, I have noticed that my extruder temp does over shoot by 2 degrees, at the most.

It hasn't caused any problems, its not the big of an issue with me.  Just wondering why my set point is being changed.  Any ideas?

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Re: Extruder Safety Issue

Are you sure the settings in slicer are at 195... slicer likes to revert settings if you don't reselect them before saving, or check you start gcode may have an additional temp code in there.

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Re: Extruder Safety Issue

Agreed,
Slic3r does forget changes that you make sometimes. At least the version provided from solidoodle website seems to do that, I'm not sure about later versions.

-It does this both while moving from tab to tab, and also when you restart the program.
-It seems to do this sometimes no matter how many times you click save too.
-Sometimes I have noticed that you can use the up/down arrow keys to change variables, and then they "stick".