Adding Thermocouples to Tips

[dhiltonp]

I've built 3 tips with thermocouples hard-soldered/brazed to the end (670C melting point): https://youtu.be/oAAN9YCJlkc

I've got a miniware D24, a generic B2 tip and a Hakko T15-D2.

Here's my "logging" the thermal performance of the B2 under 2.14.1 and 2.12b. I knew 2.14.1 was better thermally, but I didn't realize by how much!

2.12b: https://www.youtube.com/watch?v=03S4dfgHxQY
2.14.1: https://www.youtube.com/watch?v=HL8qnq7Hi8Y

I haven't done any dynamic tests yet. I have run all 3 tips with both firmwares.

The Hakko tip seems to be very accurate and responsive with both firmwares. This may be because it's a fat tip?

2.14.1 is much better for the B2 and D24. The achieved temperature much closer to the set temperature - I'm reading 5-10C over for the D24 and 10-15C under for the B2?. With 2.12b the D24 is ~30C under temp and the B2 is ~40C under temp!

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My logging hardware isn't complete - I've got to put in isolation because ground loops are an issue. So far I've just unplugged the laptop, but that won't work when I'm also collecting logs from the Pinecil!

[dhiltonp]

I re-tested with 2.14.1 with the 3 tips. The B2 is 5C over, the D24 and D2 are reading about 20C over. Thermal lag on the D24 and D2 is about 2s, the B2 is about 5 seconds.

I did touch the D24 to some solder and found it worked well - the temp almost instantly dropped to the set point, and when touching the iron to a thermal mass wattage/temp compensation is definitely present but can be improved - the tip temp was reading 20-30C low.

Roughly speaking, our temp correction code is linear with wattage but should be exponential.

[dhiltonp]

Hmmm - there is no way that the wattage correction code alone is responsible for that much drop, I'd expect to see a maybe 2-5*C correction at idle. There have been too many updates to the temp code to pin the changes on any one factor.

[dhiltonp]

21e3bab or a3f037f or 27bf2a1 or 627c491?

[Firebie]

I re-tested with 2.14.1 with the 3 tips. The B2 is 5C over, the D24 and D2 are reading about 20C over.
This can be related to different calibration offset 'systemSettings.CalibrationOffset' - for different original (miniware) tips I have tested - it varies from 650 to 950.

[discip]

@dhiltonp
I think this issue fits better in the discussions section.
So maybe you could transfer it there and close it here? 😊