Heatbed for a Kossel XL

Hi everyone, I've been building a Kossel XL lately, and it's pretty much done =)

The last part for me is the heatbed, that I bought from over there.

This is my first time with a PCB heatbed, on my two previous printer I used round silicon patch.

I'm a little bit confused about the NTC mention on this all heatbed, what is it supposed to be used for ?

I was planning to use this 100k thermistor, but there is no hole into the aluminum heatbed... What would you do ? I saw a video of a guy gluing it with a silicon blob on the surface but i'm not sure that's the best idea...

Maybe I should secure the thermistor E3D style with a screw and drilling into it the aluminum ?

And last but not least, I've read that i'm supposed to use it upside down (isn't it going to heat more my electronic than the print ???) ... I was planning to either use glass or glass with Builtak on top of it.

This project is sometimes driving me crazy !

I don't have personal experience, but it looks like it already had the thermistor already installed, the NTC which should be 100k. If you already own it, measure the resistance. Not sure why anyone would suggest running it upside down, but I would insulate the bottom of it.

Hi, the thermistor is the surface mount component in the middle of the bed. You should see if you can find out exactly what thermistor it is, as to read it correctly you need to know what resistance it has for a range of given temperatures.

The advice to use it upside down was either from the days when people used to print directly onto PCB heaters or if you are going to place an aluminium heat spreader on top which would potentially short the heater circuit by touching the solder. Yes use insulation but whichever way up you install it remember most heat rises.

Edited 2 time(s). Last edit at 09/14/2017 06:02PM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions