Nozzle not getting hot enough

I've been printing for days now with not much success due to ABS.
I tried bed heating up to 90-100 with nearly perfect results.
However, today when i was printing, i tried to take some measurements of the extruder and my hand got in the way while it was moving from right to left. It caused slight gear jump over the belt so i had to stop the build
After cleaning up the platform and getting ready for another take, i notice that hot end does not get hot enough.

Steppers work fine, fan works, bed works, nozzle temp is reading fine.
Nozzle temp is climbing very slow now, 1 degree per second VS 3-5 before.
Stops approximately at 169, stays there for few seconds and starts to drop 10-20 degrees down.

LCD Display shows Heating...ady.
Normally it would just say Heating.......

Then it starts to raise again slowly but did make it up to the 225
Print starts. Temp starts to drop. below 190 by now.
Then it starts to heat up again to 225.

Any ideas why that may be ?
Could that be power supply issues not being strong enough to give power both to the bed and nozzle heat ?
I have not done anything with firmware the last new days. I updated it once few days back so LCD from reprapdiscount wont have any issues.



Keep in mind that each block in the temp log is 30 seconds long.

I tried:
Restart the printer.
Power off and cool down for a few.
Re-uploaded firmware again in case it got corrupted.

 

After letting the printer to cool down for longer, with fresh firmware and restarting the printer it does seem to work.
Still i'd like to know what was the problem.
Is it the power supply overheated or the board ? I ask about the board because i can feel the heat it makes thru the case.

Hopefully this topic would answer questions both for me and those who would run into similar problem in the future.

Here is nozzle temp log after all the trouble:

 

Cooling fan on where ?
If i turn it on, it struggle to heat up, plus for ABS its a no-no

 

Blowing on the ramps/arduino board. Coulda been your polyfuse overheating so the thought was you keep that cool and it won't get too hot and trip.

 

Its stopped heating up again after i successfully printed small object for about 20 minutes.
Do you think blowing on the board would help ? Its those 2 yellow things set apart from each other ?
How cold do they need to be to reset ?

Thanks

 

Yes the two yellow things. I'm not certain the amp draw of the heater but it's a mfr500 so it's probably rated at 5A@25C. As temp increases the amp rating drops off so if it gets hot enough it'll trip. There should be a reasonably buffer but it's hard to say. If you seperate your poly switches it'll help dissipate heat.

 

They are separated as shown in the assembly video by robo 3d
I think what really happened is my wires went bad.
I took the nozzle off the hub and it started to heat up. I noticed this change couple of times so thats a clear indication to me that wires at the nozzle are the problem. I see some of the pinched, perhaps from the above described incident.

 

Found it !!!!!
Wire was not soldered strong enough, it broke loose off the resistor wire

Fixed and works

 

Nice!

 

What is nozzle max temperature it can get before it melts ?
How hot can it get before firmware trips to shut it off ?

I wonder caz ABS printing required 330 and up. I want to speed the print up but not sure if the nozzle can handle it.

 

The default firmware has a max temp of 235 degrees celsius. The stock hot-end cannot withstand much higher than that.

 

That blows.
Good to know about the 235.
Thanks.

Can all meta E3D go hotter ? How much hotter ?

 

Yes the E3D can go hotter. I v have my firmware set for a max of 330. Not sure what the E3D's max is. More of an issue with the heater resistor than the metal bits as I believe the limit is a function of the heater resistor. It just can't get to 500 Celsius, for example. The metal, I believe, could go there without issue.


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LOL 500 is not where i want to be, but 350 would be nice for speedy ABS print

 

Without replacing the thermistor you can't really go above 290 or so

 

its not a good idea to use solder on connections near the hot end.

metal ferrules or metal crimps would be better choice for longevity and reliability

 

Doesn't PLA and ABS have their own max temps where the material will start burning?

330 sounds extreme unless you need to do really rapid printing. I've heard that Makerbot suffers from this problem where they have to run hotter to compensate for the speed to melt the material faster. But this could cause issues with the material burning.


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But thats how it was attached. Its not close enough to the tip to melt and disconnect, its nearly 3 cm away.

 

CURA interface says 230 is recommended for ABS and 210 for PLA.

I get good results printing with ABS at 230 both very slow and fast speeds. It doesnt help to prevent curling but print layers are not separating unless i go very fast