1 Topic by Heartlander

  • Heartlander
  • Heartlander
  • Member
  • Offline
  • From: Kent from Kansas City
  • Registered: 2013-06-23
  • Posts: 904

Topic: Epoxied my thermistor

Every time I fiddle with the hot end, the thermistor wants to come out. So, I once again reset it, snugged the retainer screw, checked the circuit, then put a drop of JB Weld High Temp epoxy over the thermistor. I let is cure for 24 hours, then slowly warmed/cooled/ warmed/cooled/ heated the hot end.

Works like a charm. Checked the indicated temp against two digital temp probes, its right on.

Robox printer, HICTOP (Prusa i3 variant) Model 3DP17 printer, ELEK 2.5W laser engraver, AutoDesk 123D Design, Windows 10

Heartlander's Website

2 Reply by AZERATE

  • AZERATE
  • AZERATE
  • PRINTiT
  • Offline
  • From: Chicago
  • Registered: 2013-11-28
  • Posts: 2,077

Re: Epoxied my thermistor

This is entirely unnecessary.
I considered doing this with my v5 a couple years ago, but I found I was doing sometging wrong securing the thermistor...trial and error proved this. The v6, if properly assembled, should never slip or be inaccurate like you mentioned. After 2 v5, 2 Volcanos, 2 v6, 1 Lite6, and about 2 dozen others I've personally assembled for other users, I haven't had issues requiring JB Weld even with the v5 blocks.

If it works for you, great! But I'm afraid you may report that you need a new heating block, nozzle, and thermistor once one of the three die. Beware of permanent upgrades, my friend smile

Printit Mason and Printit Horizon printers
Multiple SD2s- Bulldog XL, E3D v5/v6/Lite6, Volcano, Hobb Goblin, Titan, .9 motor, Lawsy carriages, direct Y drive, fishing line...the list goes on
Filawinder and Filastruder #1870.....worth every penny!

3 Reply by Heartlander

  • Heartlander
  • Heartlander
  • Member
  • Offline
  • From: Kent from Kansas City
  • Registered: 2013-06-23
  • Posts: 904

Re: Epoxied my thermistor

Yeah, I know. Realize, I was typing that with one hand while preparing to throw my printer out the window with the other.

I also found that it SEEMS the epoxy causes the heat to build up around the thermistor, resulting in an higher than actual reading, i.e. the filament won't melt and you'll start having filament spills between the drive gear and hot end. SO, if anyone SHOULD do this, check your actual temp at the nole with a digital meat thermometer (get as much physical contact as you can to get a good reading) and adjust your firmware accordingly.

I do think,as you and others have said, the current thermistor mounting method is... less than optimum. Better than Kapton, sure. but still kinda bush league. Now, epoxy may be bush too but it's a lot less hassle if e'er you go getting handy with the hot end. Hopefully the next gen hot end will have a better arrangement. This is no thermistor for old men (sorry, Tarantino).

Robox printer, HICTOP (Prusa i3 variant) Model 3DP17 printer, ELEK 2.5W laser engraver, AutoDesk 123D Design, Windows 10

Heartlander's Website

4 Reply by jagowilson (edited by jagowilson 2016-01-20 19:04:29)

  • jagowilson
  • PRINTiT
  • Offline
  • Registered: 2014-09-14
  • Posts: 1,701

Re: Epoxied my thermistor

For the record, I've been using the same thermistor for about six months and haven't even had to re-tighten the bolt. Did you properly strain relieve the wires? E3D provides a nice diagram on how to do this, if I recall correctly. A zip tie between the thermistor and heater cartridge wires is usually enough to prevent any strain on the thermistor. When you perform the thermal tightening step of the E3D, I recommend cranking the thermistor bolt a bit, to get it extra tight. With the right configuration and no strain on the wires, the thermistor will stay wired in indefinitely.

Also, don't forget the washer. Without the washer it definitely won't stay secure.

5 Reply by elmoret

  • elmoret
  • Filastruder
  • Offline
  • Registered: 2012-10-11
  • Posts: 6,048

Re: Epoxied my thermistor

Seconding this. I've run on the same thermistor on my v6 for around 1000 prints over a year and a half. Haven't touched the thermistor after initial install.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

6 Reply by wardjr

  • wardjr
  • wardjr
  • Moderator
  • Offline
  • From: Minnesota
  • Registered: 2013-06-10
  • Posts: 5,624

Re: Epoxied my thermistor

elmoret wrote:

Seconding this. I've run on the same thermistor on my v6 for around 1000 prints over a year and a half. Haven't touched the thermistor after initial install.

I will take this even further,  even with the V5's that just had Kapton tape holding them in place.  I still have my original V5 from close to 3 years ago that I just re-purposed on my Workbench.  I have never touched the thermistor and it still works perfectly.  It easily has well over 1000 prints on it.  I like the setup on the V6's and haven't had a single failure of a thermistor on any of those either.  I find it to be a simple install with little room for error.

Printit Industries Model 8.10 fully enclosed CoreXY, Chamber heat
3-SD3's & a Workbench all fully enclosed, RH-Slic3r Win7pro, E3D V6, Volcano & Cyclops Hot End
SSR/500W AC Heated Glass Bed, Linear bearings on SS rods. Direct Drive Y-axis, BulldogXL
Thanks to all for your contributions

wardjr's Website

7 Reply by Heartlander

  • Heartlander
  • Heartlander
  • Member
  • Offline
  • From: Kent from Kansas City
  • Registered: 2013-06-23
  • Posts: 904

Re: Epoxied my thermistor

Yup, I always strain relieve and dress up my wiring. THe problem only comes in when I am man handling the hot end, taking off a nozzle, etc. And, yes, I do use the washer.

Robox printer, HICTOP (Prusa i3 variant) Model 3DP17 printer, ELEK 2.5W laser engraver, AutoDesk 123D Design, Windows 10

Heartlander's Website