I am trying to setup the heated bed for my printer. I am having a few issues. Once wired up I set it to heat to 40C as a test. I monitored the temperature with repetier-host and also an infra-red thermometer. The infra-red thermometer showed the temperature on the top of the bed hit near 50C while the beds thermistor eventually got to 40C. The infra-red probe showed the temperature slowly drop to 45C and stabilised there, all the while the electronics insisted that the temperature was 40C. When I set the temperature to 45C the infra-red probe showed a jump to 55C(ish) and a drop to 50C then stabilised. It seems that the temperature is reading off by 5C. I brought this (eBay) thermistor and am using Marlin's thermistor table 1 (on Megatronics 2.0). Am I missing something? https://reprap.org/forum/read.php?1,231262,231262#msg-231262 Mon, 05 Oct 2026 20:03:29 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,231262,232795#msg-232795 https://reprap.org/forum/read.php?1,231262,232795#msg-232795 -------------------------------------------------------
> Found out part of my issue, my multimeter is so
> far out of calibration it is a bin job!
>
> I used a higher quality multimeter to read the
> resistances and I am nearly spot on. Thanks for
> the blog post, kept me going thinking that it can
> be done :)

No problem.
>
> Now I just need to sort out the nichrome wire
> burning through the kapton tape. I was thinking
> fire cementing it into place?
Sounds like you have some of the "fake", or lower temp kaput on tape, as I know others use in chrome directly under laptop.

However, fire cement (exhaust putty) should do the trick if you can get it to stick to the bed surface.(I'm assuming you're still talking about the bed).]]> CraigRK General Mon, 05 Aug 2013 02:17:21 -0400 https://reprap.org/forum/read.php?1,231262,232704#msg-232704 https://reprap.org/forum/read.php?1,231262,232704#msg-232704
I used a higher quality multimeter to read the resistances and I am nearly spot on. Thanks for the blog post, kept me going thinking that it can be done :)

Now I just need to sort out the nichrome wire burning through the kapton tape. I was thinking fire cementing it into place?]]> smartroad General Sun, 04 Aug 2013 18:02:49 -0400 https://reprap.org/forum/read.php?1,231262,232152#msg-232152 https://reprap.org/forum/read.php?1,231262,232152#msg-232152
I however struggled the same as you and decided to build my own table experimentally. I was able to tee fore Aldo customise the table with closer values near the key temperature points, meaning that I could get more stable temperatures more quickly. I wrote about it on my blog http://blogger.kritzinger.net/2012/04/recalculating-thermistor-tables-more.html

Good luck,
Craig]]> CraigRK General Fri, 02 Aug 2013 14:44:39 -0400 https://reprap.org/forum/read.php?1,231262,232137#msg-232137 https://reprap.org/forum/read.php?1,231262,232137#msg-232137
I am at a total loss and have run out of ideas. is there anyone who can help me, please?]]> smartroad General Fri, 02 Aug 2013 13:46:45 -0400 https://reprap.org/forum/read.php?1,231262,231810#msg-231810 https://reprap.org/forum/read.php?1,231262,231810#msg-231810
The Huxley's bed sensor reports it at 60C but the new sensor is reporting 55C (see attached). Would it be something to do with the thermistor table?]]> smartroad General Thu, 01 Aug 2013 13:17:27 -0400 https://reprap.org/forum/read.php?1,231262,231262#msg-231262 https://reprap.org/forum/read.php?1,231262,231262#msg-231262
The infra-red probe showed the temperature slowly drop to 45C and stabilised there, all the while the electronics insisted that the temperature was 40C. When I set the temperature to 45C the infra-red probe showed a jump to 55C(ish) and a drop to 50C then stabilised. It seems that the temperature is reading off by 5C.

I brought this (eBay) thermistor and am using Marlin's thermistor table 1 (on Megatronics 2.0).

Am I missing something?]]> smartroad General Tue, 30 Jul 2013 16:57:18 -0400