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Extruder heating up then cooling down

Posted: Thu Dec 22, 2016 4:51 am
by Niallbg
I have put together my geeetech prusa i3 a pro and have just started testing the preliminarys before trying my 1st print.

My heat bed heats up fine but my extruder will not heat up above 22-27 degrees.
I've made sure the wires were secure, and when trying to use repetier host to heat up the extruder if i push the wire in for a few seconds although they are very secure heating begins and goes up slightly above my settings (if i set to 210 it peaks at 217) but then all heating stops and the extruder starts to cool and again if i push in again heating begins ect.

I can only assume that my wires are no making contact although they are secured and pushed all the way in before tightening.


Any help would be welcomed

Thank you

Niall

Re: Extruder heating up then cooling down

Posted: Thu Dec 22, 2016 4:10 pm
by Cup
Sounds like the cable has no a good contact to the connector.
The heating cable of extruder should have been tightened to the connector before heating it up,shouldn't it?
You mean you just push it in and not tighten it?

Re: Extruder heating up then cooling down

Posted: Thu Dec 22, 2016 7:04 pm
by Niallbg
The cable is tightened, but unless i push on the tightened cable( only for 2 seconds which is done up very tight) the extruder wont heat up.

When i look at one of the cables the wire does appear to be slightly recessed but I'm talking 100th of a mm.

Will try to make a better connection with the wire and board, just wonder if I was missing something else or was it this obvious especially as it was heating up then cooling down.

Thank you for your help.

Re: Extruder heating up then cooling down

Posted: Fri Dec 23, 2016 10:43 am
by William
and how is your printer now?

Re: Extruder heating up then cooling down

Posted: Fri Dec 23, 2016 8:14 pm
by Niallbg
I haven't had a chance to go near the printer yet with two children and Christmas imminent.

I will try and make the change tonight and update.

Re: Extruder heating up then cooling down

Posted: Sat Dec 24, 2016 6:38 am
by Niallbg
Pulled back the outer covering and now extrude heats up and stays hot.

Just waiting for some replacement Z axis rods as originals weren't straight.

Re: Extruder heating up then cooling down

Posted: Tue Dec 27, 2016 4:37 am
by dukeatlan
Hi,
I have the same problem but my extruder comes to an temperature of 140 degrees but after it reached it the temperature is sinking again...

I hope you can help me.

Re: Extruder heating up then cooling down

Posted: Tue Dec 27, 2016 6:20 am
by Niallbg
Did you set the maximum to 140?
Is you voltage switch on the right setting on the control box? (assuming you have the aluminum pro)
On the extruder heating cables you can pull the outer cover back to expose more of the wire befor you tighten it up.

Re: Extruder heating up then cooling down

Posted: Tue Dec 27, 2016 8:02 pm
by dukeatlan
Hi,

I sat the temperature to 195 degrees and the wires are secured correctly.
The LED which shows that it powers the the extruder is allways active and also if the temerature goes down it still lights up.

Re: Extruder heating up then cooling down

Posted: Tue Dec 27, 2016 9:03 pm
by Niallbg
The issue I had with heating up and then heating down again was due to not enough wire being exposed. I had about 3mm exposed.