Soldering irons and their tips come in a wide range of formats and styles, with the (originally Hakko) T12 being one of the more interesting offerings. This is because of how it integrates not only the tip and heating element, but also a thermocouple and everything else in a self-contained package. In a recent video [Big Clive] decided to not only poke at one of these T12 tips, but also do a teardown.
These elements have three bands, corresponding to the power supply along with a contact for the built-in thermocouple. After a quick trip to the Vise of Knowledge, [Clive] allows us a glimpse at the mangled remnants of a T12, which provides a pretty good overview of how these tips are put together.
Perhaps unsurprisingly, most of the length is a hollow tube through which the wires from the three contacts run. These power the ceramic heating element, as well as provide the soldering iron handle access to the thermocouple that’s placed near the actual tip.
With a simple diagram [Clive] explains how these T12 elements are then used to regulate the temperature, which isn’t too distinct from the average soldering iron with ceramic heating element, but it’s still nice to have it all integrated rather than having to try to carefully not damage the ceramic heater while swapping tips with the average soldering iron.
Clive is a great creator. Fantastic to seem him featured here
If you are the kind person that generally damages heating elements during a soldering iron element swap, then I don’t think soldering is for you…
In 40 years I have only had to swap one heating element in a soldering iron (in a Weller that had 30 years on the “clock”), so I don’t think the T12 tips actually solved a problem. What they did was create a market for themselves creating over-priced tips (and waste more resources than necessary).
The problem they solve, is the poor thermal coupling between the ceramic element and the tip which you get with all soldering irons with removable tips and fixed heaters. Also, it places the temperature sensor very close to the tip of the iron.
Pretty much every high-end soldering iron nowadays has tips with heating elements integrated. Even Weller does that, although I would hardly call Weller high-end nowadays. This means you can put a lot of power into a small tip very quickly. My JBC heats up in a couple of seconds, and even a small tip can be used to solder on large ground planes.
A thermocouple has a resistance of nearly zero, which is why they can place it in series with the heating element. Turn off the heater, sense the voltage, turn the heater back on. Very clever!
They also heat up a lot quicker. That allows the soldering iron to reduce temperature when you put it in the holder, which extends the tip life significantly. They heat back up to the set temperature in a few seconds when you pick the iron back up.
Try using one, im absolutely a convert, I do automotive electronic repair, so one second i may be using the iron to heat the heatsink on some surface mounted power IC requiring a nice wide heavy tip to aid its removal, in seconds i can swap it out for another tip, again in seconds its back up to temp and I have a fine fine tip for soldering the legs on the replacement IC .
I had a cheap “Aoyue” unit that uses the same temperature measurement scheme, and the ring contacts had to be pristinely clean for it to work. Every fscking day the damned thing would throw an error and I had to remove the tip, clean, reinsert. Cleaning the terminals inside the handle, using contact cleaner, alcohol, whatever, never worked.
I finally terminated it with extreme prejudice and went back to my good old Weller.
I don’t know what magic sauce Hakko uses to make the millivolt temperature measurement reliable (if any), but that experience has dissuaded me from ever trying this kind of iron again.
Not to say Weller is immune to this… Their RT tips are just as bad. I’ll stick with my clutch of ET tips, thankyouverymuch. But I do miss the PT type tips, with the Curie-effect sensor.
ET tips for me. My Magnum irons also use the ET style tips…(Magnum is a South African brand of soldering irons, SMD stations, etc…). Oldest one is now going for 24 years with no element swap, and I have a decent supply of tips (the tips are actually EW, but it is the same ET measurement scheme that Weller uses).
Hehe… the first time I used a Weller (with PT tips) was while installing radios in city busses in Joburg. Never heard of Magnum. Maybe they didn’t exist back then — I left the country and have not been back since ’83.
Started around the early 90’s, producing mostly for manufacturing line use (solid metal case, memory keys to quickly update settings and lock them down, etc…typical use for a manual-solder production line). They were however so robust, that it didn’t take long before you saw them in almost every workshop you walked into. This lead to the smaller models mostly meant for electronics workbench use. Bought my first model 2002 in 2000…never looked back. All spares always available, but the only parts I always buy is tips. Located in Marlboro if you can still remember Jhb layout… :-)
I started off as student in SABC radio in ’90 (Auckland Park), which was a Weller house then. By 1995?…Magnums all over…workshops and labs.
That’s weird. I have a ts-100 that uses similar tips and I’ve never once had an issue with it. And I use it professionally.
Yup. The TS100 was good, and the Pinecil is great. IronOS does a fantastic job.
just loosen the locking ring and give the tip a twiddle while powered up almost always works for me.
You used a cheap and nasty device and decided that it must be the technology that is flawed, not the implementation? Ok then.
I use this soldering iron with a USB-C battery and I never want another! Heats up extremely fast, gives off a lot of heat and I dont need a power outlet. Also changing tips is easy to switch between thick power plugs and SMD, all with the same cheap device.
Pinecil along with a 65W PD power bank, a compact 3Dp case (with cable, iron stand, brass wool, solder, wick, flux, & tips), and finally an Engineer SS-03.
Oh, and a thumbscrew on the Pinecil for toolless tip changing.