Irons that use 900M soldering tips... and why I dislike them
I've seen people here ask and recommend various soldering stations. Unfortunately, most stations that get recommended are the Hakko 936 clone ones (or a version of that) with 900M series tips. Nothing wrong with that, but in my opinion, all of those perform about the same and if you are getting a station like that, don't spend a fortune on it. Rather, if you really are serious enough about getting a "proper" soldering station, you might as well spend just a little bit more and get something with T12 and T15 tips.
So why all of the dislike for 900M stations/tips? Let's take one apart and see...
Here's is your standard 900M iron handle. I put a 3 mm chisel tip on there:
All taken apart, showing the ceramic heating element:
https://www.badcaps.net/forum/attach...1&d=1431575036
And the mini PCB pulled from the handle:
https://www.badcaps.net/forum/attach...1&d=1431575036
https://www.badcaps.net/forum/attach...1&d=1431575036
Now, let's note something here: the thermocouple/temperature sensor is inside that thicker base which is holding the heating element to the PCB (under the spring).
But now let's see what happens when the tip is on the heating element:
Anyone see what's wrong with this picture? No, not yet?
Well, you have the tip on one end (left) of the heating element and the thermocouple/temp sensor all the way on the other end (right). So how exactly is the thermocouple going to pick up the temperature of the soldering tip? Short answer - it won't.
Rather, the way it works is that the thermocouple just keeps the temperature of the heating element to whatever temperature you set the station to. As the soldering tip sits over the heating element, it eventually equalizes to the heating element's temperature (if the iron is not being used, of course). But once you start soldering, that soldering tip will drop in temperature, whereas the temperature of the heating element won't change drastically. You leave the iron for a bit, and again the tip will get to the heating element's temperature.
So the result is poor thermal control. And that's why so many people crank these stations up to 300C just for leaded soldering, and much higher for lead-free.
With T12 and T15 tips, both the thermocouple and the heating element are embedded in the tip. This is why those tips have much more superior heat control (and why each T12/T15 tip costs around $10 a pop too). But IMO, that investment is worth every penny. You will be able to solder lead-free stuff even on as low as 260-280C temperature settings with those T12/T15 tips.
Anyways, I don't mean to steer anyone clear of stations that use the 900M tips. Rather, just trying to inform of what to expect from them. Obviously, if you can get it very cheap, go for it. They do have some benefits over regular/standard mains plug-in irons. But otherwise if you want a more serious station, just go for something that uses T12/T15 tips, even if it is a lower wattage than the offerings you may get from stations that use the 900M tips.
I haven't been following on what are the latest trends for these temperature-controlled soldering stations, but I know that Aoyue 2900 was one of the more inexpensive units a few years back. Circuit Specialists also sold a clone of that for about $60 last I checked. Another alternative is Hakko FX-951 - if you can find one that is genuine, of course (though, on that note, I will say that I have tested a "counterfeit" FX-951 station, and it still worked quite okay... just didn't have sleep function and soldering and built quality inside were low).
So why all of the dislike for 900M stations/tips? Let's take one apart and see...
Here's is your standard 900M iron handle. I put a 3 mm chisel tip on there:
All taken apart, showing the ceramic heating element:
https://www.badcaps.net/forum/attach...1&d=1431575036
And the mini PCB pulled from the handle:
https://www.badcaps.net/forum/attach...1&d=1431575036
https://www.badcaps.net/forum/attach...1&d=1431575036
Now, let's note something here: the thermocouple/temperature sensor is inside that thicker base which is holding the heating element to the PCB (under the spring).
But now let's see what happens when the tip is on the heating element:
Anyone see what's wrong with this picture? No, not yet?
Well, you have the tip on one end (left) of the heating element and the thermocouple/temp sensor all the way on the other end (right). So how exactly is the thermocouple going to pick up the temperature of the soldering tip? Short answer - it won't.
Rather, the way it works is that the thermocouple just keeps the temperature of the heating element to whatever temperature you set the station to. As the soldering tip sits over the heating element, it eventually equalizes to the heating element's temperature (if the iron is not being used, of course). But once you start soldering, that soldering tip will drop in temperature, whereas the temperature of the heating element won't change drastically. You leave the iron for a bit, and again the tip will get to the heating element's temperature.
So the result is poor thermal control. And that's why so many people crank these stations up to 300C just for leaded soldering, and much higher for lead-free.
With T12 and T15 tips, both the thermocouple and the heating element are embedded in the tip. This is why those tips have much more superior heat control (and why each T12/T15 tip costs around $10 a pop too). But IMO, that investment is worth every penny. You will be able to solder lead-free stuff even on as low as 260-280C temperature settings with those T12/T15 tips.
Anyways, I don't mean to steer anyone clear of stations that use the 900M tips. Rather, just trying to inform of what to expect from them. Obviously, if you can get it very cheap, go for it. They do have some benefits over regular/standard mains plug-in irons. But otherwise if you want a more serious station, just go for something that uses T12/T15 tips, even if it is a lower wattage than the offerings you may get from stations that use the 900M tips.
I haven't been following on what are the latest trends for these temperature-controlled soldering stations, but I know that Aoyue 2900 was one of the more inexpensive units a few years back. Circuit Specialists also sold a clone of that for about $60 last I checked. Another alternative is Hakko FX-951 - if you can find one that is genuine, of course (though, on that note, I will say that I have tested a "counterfeit" FX-951 station, and it still worked quite okay... just didn't have sleep function and soldering and built quality inside were low).
Attached Files
Comment