Print Head Can't Get to Temp after Head / Temp Sensor Replacement

[taberhsmith 0]

Hi,

Well I just replaced the extruder head and the temp sensor. I put it all back together and tried to print a test, but the print head only seems to get to 155C and then just stops. I'm pretty sure the heater is good because I used it to melt the ABS out of my old head.

Since I didn't really have any instructions on re-assembling this thing, I have a few questions...

- Are you supposed to use any thermal grease around the heater or just shove it in the head as far as it will go?

- How far is the temp sensor supposed to go in? If you push it in as far as it will go, then the wire is pretty far in. It didn't seem like my last one was like this. Any thermal grease on this piece?

Any thoughts on what might be causing the temperature to not get hot enough?

Are there assembly disassembly instructions for the head assembly anywhere?

Thanks!

T

 

[DidierKlein 729]

Hi,

You can have more information on how to disassemble the print head here:

http://support.3dverkstan.se/article/25-removing-the-ultimaker-2-nozzle

There's a video too:

 

And you can download the assembly manual here:

https://github.com/Ultimaker/Ultimaker2/blob/master/um2%20assembly%20manual%20V1.1%20_english.pdf

You don't need thermal grease for this. Check in the manual if you assembled it correctly?

Maybe the temp sensor isn't wired correctly?

 

[gr5 2,172]

You don't need silver grease but it definitely helps. Make sure it is rated for at least 300C.

Be very careful - if the temp sensor says 155C and you are asking for a higher temp it will pump more and more power into the heater and it can melt everything in the head (when it gets up to around 300C). So just because it *says* 155C it is likely pushing it's way to 300C if you leave it on like that for a whole minute.

 

[gr5 2,172]

put a drop of water on the head. You should be able to see tiny furious (in their tiny way) boiling bubbles at around 110C.

 

[gr5 2,172]

Also push filament against the outside of nozzle when it is at "155C". It should not melt at all. If it melts then cut power fast as it is over 200C and maybe heading for 300C.

 

[taberhsmith 0]

Thank you for all the information.

I took the unit apart and pushed the temp sensor (which is new) in all the way and put it back together and the problem seemed to get worse, it's now maxing out around 115C.

I tried feeding the filament through and it wouldn't go, so I guess that means that the temperature really is only 115C.

So, now the question is do I need to replace the heater or is there something that I can do to solve this?

Thanks,

Taber