Thermister broke loose... fix???? am i crazy?

[dunginhawk]

Ok, so as a few folks on here that read often know, im new here i spent a lot of my day on chat with Guanu and JJ... Most helpful guys in the world, thank you.

So my day.

printed the peek shroud- didnt turn out great. somehow it was 4mm taller (im guessing scaled up somehow all around) than it should have been... so scrap that.
Went on to print the layer fan. Not sure if its the right size yet or not, but ill check... quality is still suspect.

Tried to print another peek shroud but the hot end thermister broke loose and smoked before i knew it. The grey plastic part (dont know what its called off the top of my head) started to deform and the nozzle was askew about 25 degrees.
I let it cool.

Back at it.... with the head upside down in a vice.. I heated the head back up, SLOWLY, just to the point of malleable plastic grey piece. I held it in place, as close to level as I can (its quite good) until the head cooled enough to hold it on its own.

I then let it finish cooling. removed by hand as much of the High temp RTV around and in the head as i can, refilled the cavities, and re-set the thermister inside the hole. I made sure i was VERY liberal with the RTV this time.

So now its curing... I wait...

SO my question to the board is..... What are the chances this has any chance of working again? And even if it works, any chance of it working well?
Reason i ask is, im considering buying another hot end, and asking the folks at seemecnc to overnight it tomorrow so i can have it friday.... If i wait for this to cure, i wont get that chance tomorrow.

Sorry for the long post, but im so excited to get to printing, and yet, set back after setback stops me.

[Captain Starfish]

You sound like you're already in a world of uncertainty regarding print quality.

A new hot-end from SeeMe isn't that expensive and would remove a whole bunch of unknowns, returning you to where the unknowns are those that others have encountered before and for which you might get assistance.

I'd be giving that PEEK block the boot at the very least. If it wasn't for the nightmare of epic self abuse that is trying to send anything via Australia Post I'd offer to send you one of my old ones (I've moved on to an E3D). There may be another member closer to you in a similar position.

[Earthbound]

When the RTV has cured, wrap the wide part of the hot end (where the resistors and thermistor are) with kapton tape to provide some protection for the thermistor. The RTV has almost no adhesive property once it is cured, so it doesn't take much force to dislodge the thermistor if only RTV is holding it in place.

A whole hot end is an option, but you really just need a new PEEK section which they sell separately. Buy a spare thermistor while you're at it. If your kit shipped before the changeover to acetal u-joints, you might consider upgrading to those as well. I just bought mine last month and I got the aluminum ones, which I am already wanting to change out.

[dunginhawk]

Good advice. I will wrap it. And try it.

With regards to quality. This was a brand new build and these were the first prints. Shouldn't quality be based on settings? Tuning the printer for heat , extrusion etc? If this happens to work then I'll have to dial in the quality. Of course I'll have to figure out how . Thanks

[nitewatchman]

I would second wrapping the hot end to capture the thermistor but you may find Silicon Tape to be a little more compliant and easy to handle. Even though I use a screw-in thermistor on the SeeMe hot end, I still wrap it for insulation.

[PrintableStudios]

Given the surgery you are going to have to perform, a threaded thermistor would be a good upgrade.

They are fairly simple to make if you have patience working with small parts. If not there are a few sources available around the web.

It just requires tapping the thermistor hole.