[Solved] Hooking up the power resistor & thermistor - how to?

Finally got back to my Prusa RepRap (inc Wade's geared extruder) build today…
Can I clarify some things to do with connecting the power resistor & thermistor into the hot end?

Here's what I have:
I have silcone adhesive sealant and also some heat sink compound
Sealant
Data sheet

The tech data sheet for the silicone says Thermal conductivity : 0.20 W/mK (I don’t understand that).


I bought a set of hook up wires, from reprapworld inc wires for the thermistor
Set of wires

note for the thermistor this includes 2 sets of wires , each set has a 2 pin connector at one end & a red & a black wire at the other end, 4 wires in total.

I also bought 2 heater wires , one red , one black
heater wire

I wasn’t 100% sure if these were for the power resistor approach or for the nichrome wire approach. I got a pair anyway.

I have a roll of Kapton tape.

(Electronics is RAMPS 1.4/Arduino).


I can think of two ways to keep the power resistor in place with what I have:
use the silicone on its own (if I'm advised it has the thermal conductivity)
use heat sink compound , but seal the ends of the power resistor with a little silicone sealant

Q1: does the silicone adhesive have the needed themal conductivity?
Q2: is one of the above two approaches better?

the wiki says:
"Insulate the join with heat-shrink sleeving."
wiki for geared extruder nozzle

A google search indicates max temp for heat shrink of appro 135 deg C , below the approx 200C the hot end reaches.
Q3 So is the wiki right to say use heat shrink? should I be using kapton tape to insulate instead?

Q4 Am I right in that the heater wires are used to hook the power resistor to the electronics?

Looking a the wiki , I expected one end of the thermistor to go to one pinout on the elctrocnics via the red wire, likewise the other end via the black wire.
Q5: so any idea why I have two sets of thermistor hook up wires (4 wires in total) in the kit?

Q6: again, for electrically insulating the thermistor , is kapton preferred over heat shrink sleeving?

Any other tips along the way welcome!

Thanks in advance.

Mike

Edit: I figured out the answer to Q5. One of the leads is for a heated bed (my inital build is minus a heated bed).

Edited 7 time(s). Last edit at 12/19/2011 02:15AM by 3D2B.

I glue in both the thermistor and resistor with heat resistant silicone and nothing else, I then solder the wires to both and run them back to the board.

I don't bother with Kapton, I use heat proof heatshrink over the soldered wires

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Experimenting in 3D in New Zealand

Thanks NelsonRap. The puzzler over the two thermistor wires had me stopped, but I figured that out.
There's a few different ways to go. I wasnt sure about soldering, the wiki said use bootlace ferrules instead, but obviously it's worked ok for you so gives me another option.
I can move forward on this bit now.

Mike

Well the heatshrink is just to stop shorting across the wires, bootlace ferrules would do the same I just like having them soldered to stop them coming apart

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Experimenting in 3D in New Zealand