Soldering iron temperature calibration - Page 1
Forum section: electronics / general

author: lpc32
author_rank: Frequent Contributor
timestamp: November 16, 2014, 06:07:53 pm
content: Should something like this be sufficient for temperature calibrating a soldering iron?I'm getting slightly inconsistent readings, maybe because it's difficult to touch the tip tightly.Would you expect to see at the tip exactly the set temperature, or just ballpark due to oxidation/no solder on tip?Do you need to calibrate at multiple temperature points, including the highest possible?

author: saturation
author_rank: Super Contributor
timestamp: November 16, 2014, 07:22:37 pm
content: https://www.eevblog.com/forum/chat/do-you-calibrate-your-soldering-station-if-not-or-if-so-why/30/https://www.eevblog.com/forum/chat/soldering-iron-calibration/msg89543/#msg89543

author: lpc32
author_rank: Frequent Contributor
timestamp: November 16, 2014, 10:38:54 pm
content: 3roomlab: Nice. But I'm not looking to retrofit stuff, just use an existing calibration option.saturation: Interesting. Still, not sure how to get consistent readings with this, and what temperatures to calibrate at.I'm unable to clean up some thruholes, including solder with paste-like behavior at times, so I thought it could be useful to remove one variable by having a known tip temperature.

author: dannyf
author_rank: Super Contributor
timestamp: November 16, 2014, 10:41:17 pm
content: QuoteWhat's sufficient is highly subjective: what's sufficient for you may not be sufficient for me and vice versa.However, I have used that set-up to get a sense of temperature and to help caliberate my own solder stations - not for precision but for ballpark figures.

author: saturation
author_rank: Super Contributor
timestamp: November 18, 2014, 12:45:56 pm
content: To summarize the links:You can use eutectic solder to spot check a specific temperature setting on your station; the melting point of such solder is very specific.The scale markings of your station will show its linear [ e.g. equally spaced labels] or not, if linear one data point is the same throughout, but follow your makes calibration instruction if existent.With a good tip thermocouple, you can always spot check the other points on the scale, starting from the eutectic solder point as a reference.The thermocouple should be immersed in liquid solder. The thermocouple sensors designed for testing soldering iron tips are sensitive and tiny, even the cheapo clone ones work very well, so its easier to immerse it that a bigger one.

author: lpc32
author_rank: Frequent Contributor
timestamp: November 18, 2014, 11:07:02 pm
content: Will a poor thermocouple like the photo above stand being immersed in solder? I think it was nominally rated up to 230C (nevermind the 125C heatshrink).It's the Hakko FX-888D. There are no calibration instructions other than describing how the interface works, and suggesting when to do it.As for using solder as reference, I randomly checked 63/37 at 190C or a bit less. It melted, but not easily.Quote from: dannyf on November 16, 2014, 10:41:17 pm.001C would be enough.

author: GEuser
author_rank: Frequent Contributor
timestamp: November 19, 2014, 03:06:15 am
content: Op , I use that in your post , I make a solder blob and stick it in it (around 3mm or so blob) .

author: Shock
author_rank: Super Contributor
timestamp: November 19, 2014, 04:17:32 am
content: A cheap option is to go for a fake hakko fg-100 $10, mine is shownin this thread here.These are designed (or at least a legit fg-100) to calibrate irons/stations and you will have no problem with solder on the tip. I expect you could also simulate thermal recovery situations. The thermocouples are reusable but considered a consumable. I got a few thrown in with mine, they are not expensive to order more.If you wanted bulletproof accuracy you could run a few tests to ensure you had confidence in the fg-100s measurement, mine was consistent but I did not attempt to calibrate it.Or if you have a few hundred dollars to throw at it. Then buy the real thing and have a consistent and hopefully calibrated unit.

author: lpc32
author_rank: Frequent Contributor
timestamp: November 20, 2014, 11:45:36 pm
content: Quote from: GEuser on November 19, 2014, 03:06:15 amSo despite being rated for 230C your thermocouple end can stand 400+? At what temperature did the heatshrink burn?Quote from: 3roomlab on November 19, 2014, 02:31:43 pmYou mean depending on the tip you get a different range of temperature readings using the same set of thermocouples?Quote from: Shock on November 19, 2014, 04:17:32 amI really don't get that pricing. A very simple device that costs more than the iron. Maybe one day I'll get that $10 copy, but even that seems redundant if a DMM is enough.

author: GEuser
author_rank: Frequent Contributor
timestamp: November 21, 2014, 05:38:52 am
content: Quote from: lpc32 on November 20, 2014, 11:45:36 pmLOL , both mine says 300c rated and I've used 2 and they still work (or seem too) after using them to set the iron at 350c , no burning anything either as a 3mm solder blob is just larger than the temp sensor blob , or maybe the solder blob is 2mm I do not get out a digital vernier gauge to measure it , its a guess .It does me for now ...