Recommendation for a temperature-controlled iron


#1

Sorry this is a bit off-topic, but do you have a recommendation for a temperature-controlled iron?

I’ve been looking at irons a bit, and there are ones like Weller WE1010NA and Hakko FX888D-23BY that have a digital temperature control. However, some of the comments suggest that these are “open-loop” control, and don’t actually use feedback from a temperature sensor. How do I tell which soldering irons have “closed-loop” control?


Fab thinks board has short circuits, but it passes DRC
#2

You can strengthen pads significantly by putting a few via’s in them.
This is common practice for the mechanical pads for SMD connectors.
When soldering wires directly to pads it is a good idea to put them through a hole and solder them on “the other side”, or even put them through 2 holes, which give a quite usable stress relief for the solder joint.
(Glue the wire to the PCB?)

Have you cosidered drawing the zone outlines in a CAD package, save it as DXF and then import it in PCBnew?
(I’m not sure this works, but it might be a good idea if it works.)

Try the TS100 From Ali / Ebay.
This USD 50 Iron is probably better than the USD 300 Weller PU81 I bought a few years ago.
All Irons with adjustable temperature have a form of closed loop control. It is the only way to control the temperature.
2 important factors are the power of the Iron, and the speed with with it heats up (also reacts to temperature disturbances). The TS100 is quite good in both aspects.
For better Irons you need to go to JBC or such, but expect to pay then USD 500 or more.
The USD 50 TS100 seems to outperform most of the USD200 class Irons.
I also saw some youtube reviews where it was deliberately destroyed, overheated , tip filed down etc. It looks a quite robust Iron. Replacement tips are also quite reasonable in price, Only limit is that there are not very many different tips available for this Iron.


#3

Thanks! Do you find it works well for bench use? (Not just portable use.) Would this be a good power supply to use with it?

I guess I was mislead by this Amazon review, which claims the FX888D “DOES NOT have a sensor at the soldering tip/handle assembly.”


#4

I have not used the TS100 myself, because my Weller PU81 is “adequate”.
The power supply you selected is right at the limit of the TS100 spec.
I do not know how tight your buget is, but for a 24V power supply I would probably use an 80W or more just to have a bit of spare capacity.
For me, if i’d use it at home, the size of the power supply would not be very critical. I would probably use a 24V10A supply in a metal encasing, an old fashioned transformer +bridge +elco from the parts bin or add a small smps board to the raw internal output of my lab power supply to make 24V.
Lot’s of people seem to be happy running it from a 19V laptop brick.

About the sensor thing:
In a lot of (the cheaper) Irons the heating element itself has a PTC resistance which is measured by the control loop. In others there is a separate sensor just for measuring the temperature of the tip itself, which is more accurate than measuring the temperature of the heating element.

One of the reasons I like the TS100 so much is because the software and schematics are freely availabe.
It has an STM32 controller, if it is your thing, you can write custom software for it. I would not be surprised if there is already custom software available for a lot of small variants, for example to limit power consumption for an under powered 24V supply. I also like features such as the built in accellerometer, which can for example be used to turn down the temperature to save the tips after some time of not using it, or completely shutting off the heating element if you forgot to unplug it late in the evening.


#5

Definitely a misleading review by an uninformed user. No soldering iron has a sensor embedded in the tip of the tip. Using a conical tip that comes to a 0.8 mm point for example is never going to transfer as much heat as a chisel tip regardless of it’s temperature, there simply isn’t enough surface area. You need to use the correct tip for the job.


#6

We have some FX888’s at work. I don’t know anything about their internal design but I am satisfied with their overall performance.

Yes, choosing a suitable tip is important. And even a 50W or 60W iron is going to struggle with “heavy” soldering tasks. Just yesterday I was soldering the shield braid of some coax cables directly to the ground plane of a board. I grabbed a second FX888 from the work table next to mine and (with a bit of juggling) the solder wetted the shield braid and flowed nicely onto the ground plane.

The TS100 looks interesting. I suspect I would need a little practice to master the ergonomics of using it efficiently - the tip seems to be a long ways from the handle, so it will take some well-developed fine muscle skills (and no shakes) to get it onto fine-pitch parts.

Dale


#7

Yeah, that’s probably my biggest concern. It just looks like it would be awkward to use, and fine muscle skills are not something I have an abundance of, even with a standard soldering iron.


#8

Size is hard to judge from pictures.
The TS100 has a pretty thin handle which can easily make you mis-judge the size of the rest of the TS100.

Because the handle is so thin you can also easily make a thicker handle from a pice of plastic pipe or a hollowed out broom stick around it and move the grip position closer to the tip.


#9

I have an old Weller WSD80 controlled iron. It has worked well for me. I was even able to solder an 0402 resistor, and tin #16 wire. I have about a half dozen different size tips so I can get select a size appropriate to the task.

This iron is temperature controlled, the sensor is at / near the base of the tip. It is not in the tip. However any temperature loss between the sensor and the tip appears to be negligible.

Note, just a important as the iron is the solder used. To solder the 0402 I needed some 0.25 mm solder, but normally I use 0.8 mm no clean 67/37 solder.

The Weller might be overkill for the hobbyist but you couldn’t go wrong in my opinion.

The companies I’ve worked for have always used Weller, so I have no opinion on the Hakko.


#10

The FX888D is fantastic - it’s definitely not open loop, there’s a sensor. It’s just not in the very tip. Ironically, what I don’t much care for is the “D” part - I find the digital controls clunky. I wish I’d tracked down the no-longer-made FX888 with the analog control.

My previous one, a Chinese knock-off of an older Hakko, the Aoyue 936, was quite good but nowhere as good as the 888. I liked the analog control better, but it took way longer to recover temperature.


#11

Well I’m going to put in a vote for the Metcal PS-900.
In these irons the tip is also the temperature sensor - they use induction heating and sense the curie point of the tip to control the temperature.
This means the temperature is not adjustable - and thats a good thing! With the tip itself being the temperature sensing element, the iron is very responsive to heat loading and can ramp up the power quickly without overheating. Much safer for your silicon parts. This iron can safely and successfully solder a SOT-23 to a solid copper ground plane with no risk of thermal damage to the SOT-23. With most other irons to have to crank up the temp to store enough heat in the tip to do the job, which means a high thermal shock, and risk of over heating.

No I don’t own any shares in Metcal :grin:. I just love their irons - been using them for nearly 20 years, and nothing else comes close, in my opinion. And I’ve used quite a few over the last 40 years - from my original 25W Antex, to Weller and Hakko models of various shapes and sizes.


#12

I haven’t seen it mentioned, so I’ll mention it. My regular soldering station is the Weller WESD51. US Amazon link It is comparable to the Hakko FX888D, but the temperature setting is much more intuitive (just spin the knob) and the Weller ET series tips tend to be less expensive than the Hakko tips. (Or they were when I did a comparison check about a year ago.)


#13

What kind of budget do you have for your soldering iron?

Sometimes I see temperature controlled Irons on Ali / Ebay starting from USD20 and these might be fairly usable for a few years, replament tips could be a problem.
The TS100 with it’s USD 50 range will probably outshine most iron’s twice it’s price (But the price difference is a lot less if you have to buy a power supply) and what I’ve seen of it it looks like it will last many years.
The Irons TwoSpoons suggested with the induction heating probably start at around USD300.

For myself I would not buy an Iron without an adjustable temperature.
I often need a hot iron for burning of the lacquer of wire and turn the temperature down again for more “conventional” soldering.

I also prefer analog readout (potentiometer) over digital (buttons). A flip of the wrist is a lot faster than holding a button for some time and waiting untill the display overshoots, then adjust a bit back the other way, and a few degrees off is not important for a soldering iron.

If you do any rework / replacement, then having 2 irons to simultaneously melt both pads on a SMD resistor / capacitor can be very handy.


#14

Thanks so much for everyone’s advice!

I’ve decided to get the TS100, and hope the ergonomics work out.

I’d been hoping for something in the low USD100’s, so the TS100 plus power supply easily fits within that.

I just use Chip-Quik for that. (Though I will have two irons now if I need them, between the TS100 and my old non-temperature-controlled Weller WLC100.)


#15

I’d love to hear your thoughts on the TS100 after you’ve used it for a bit. I’ve been interested in it, but since my current iron still works the justification isn’t there. (Although I’m thinking of seeing about upgrading my local maker group’s soldering class irons from the crappy $15 pencil irons they currently use…)

FWIW, I didn’t suggest it only because I don’t have any experience with it.


#16

I’ve been using my TS100 for about a day so far. My overall impression is positive. I think it would be an excellent portable soldering iron. It’s good for bench use, too, but there are some compromises.

I like how quickly it heats up. (I’m using a 24V power supply.) I found that it went from room temperature to 340°C in about 9 seconds.

When it hasn’t been used for a little while, it reduces the temperature to 200°C. I found that it would heat back up to the set temperature in about the amount of time it took me to take the iron out of the stand and move it to my board, so I didn’t have to wait for it at all.

The ergonomics turned out not to be a problem. The tips that the TS100 uses are much longer than normal soldering iron tips. But the thing to keep in mind is that a normal soldering iron has a long metal section in between the plastic handle and the tip. In the TS100, the tip plugs directly into the plastic handle; there is no metal section in between. So the distance between the end of the tip and the place you hold the iron works out to be about the same, or slightly shorter.

Here is a picture that compares the TS100 to my old Weller WLC100:

I found it comfortable to use, and the different size and shape didn’t seem to be a problem.

The TS100 does not come with a stand, so I used a 35-year-old stand from Radio Shack that I had lying around. It worked, but since the TS-100 is so thin, it goes much deeper into the stand than a normal soldering iron. This made it slightly more awkward to take it out of the stand, and it also means there’s a danger of melting something accidentally, because the tip protrudes beyond the end of the stand.

The thing I dislike most about the TS100 is that it requires a separate grounding wire. This means that you have both a power cable and a grounding wire going to the iron, which is awkward. I used zip ties to attach the grounding wire to the power cable, to make it act more like a single cable. However, it still meant that the cable coming out of the iron was relatively heavy and cumbersome, especially compared to how small and light the iron itself is.

Overall, though, I found it pleasant to use, and a good upgrade over my WLC100.

The specific items I bought were: