I2K Insulator Woes

[drofnas 15]

So for the past month I've been having a TON of under extrusion issues, to the point that I actually bought a new (mini) printer just so I could finish my current project.

I've tried replacing my bowden tube, teflon (DUPTEF, then TFM), nozzle (have Olson Block), spring replacement (based on korneels), steel coupler, and even went back to my original fan shroud (had laberns installed), but nothing seemed to work. Then finally on a whim I decided to remove the i2k insulator and put back on the spring and now I'm actually getting successful prints again. Right before I removed it I had tried pushing some filament through and noticed that my filament had stopped right around the teflon tube no matter how much force I used.

After waisting all this time and money, if anyone is having any under extrusion issues and has the i2k installed, please try removing it and see if that helps. When I removed mine it was a little sticky, like it melted a bit, I thought this was supposed to be more robust then the Teflon. I think I had "maybe" printed 150hrs (210C-230C) with my i2k installed before my issues had cropped up.

With that, I'd have to say pass on the i2k insulator and just get a couple Teflon (TFM) backups instead. (IMHO)

[neotko 1,417]

Just one question. Your ptfe had the 1mm bottom cut? I know that Swordriff cuts the ptfe coupler 1mm if it's for I2K use. Also it's weird the i2k could melt, that stuff can go 360C, or so, without problem.

[drofnas 15]

Just one question. Your ptfe had the 1mm bottom cut? I know that Swordriff cuts the ptfe coupler 1mm if it's for I2K use. Also it's weird the i2k could melt, that stuff can go 360C, or so, without problem.

 

Nope, I was using the original spring at first then switched over to the spring replacement (printed in ColorFabb XT):

https://www.youmagine.com/designs/um2-spring-replacement-for-i2k

I hadn't read anywhere to cut the ptfe coupler when I purchased the i2k a few months ago.

Maybe I got a bad batch, not sure... but it was the last thing in the path of the filament I could think to change/remove, so it "seemed" to be the root cause of my printing issues.

[neotko 1,417]

I really don't know but Carl told me by phone that the ptfe tfm coupler he sent me was 1mm shorter to be used with the i2k, also he told me that it will not work without it because of that.

[Dim3nsioneer 557]

A 1mm shorter TFT coupler allows for using the hotend spring with the original tension or the standard Korneel spacer. However, it should be possible to use even the spring with the standard size I2K (my UM2 is configured for now over half a year with an I2K and a DupTef - no issues so far).

@drofnas: You write that you use a spacer based on Korneel's design. Can you please comment on the differences?

[drofnas 15]

A 1mm shorter TFT coupler allows for using the hotend spring with the original tension or the standard Korneel spacer. However, it should be possible to use even the spring with the standard size I2K (my UM2 is configured for now over half a year with an I2K and a DupTef - no issues so far).

@drofnas: You write that you use a spacer based on Korneel's design. Can you please comment on the differences?

 

This one:

https://www.youmagine.com/designs/um2-spring-replacement-for-i2k

It's based on Korneels, just shorter in height to account for the i2k.