Deception In Soldering Iron Ratings

[MrAl]

Hi again,

Yes too much deception and nobody does anything about it.

The reason i went to a controlled iron is because of two main factors:
1. The iron temperature can be turned down but not off, so it heats up really fast when needed again. No more leaving the iron on for hours just to use it for a few minutes or so.
2. The controlled iron has the ability to heat up fast. I can start to solder within maybe 20 seconds. With all my other irons it takes at least 90 seconds or more, and this makes a big difference when you have to repeatedly repair little things like clip leads. I would hate when a clip lead alligator clip would break off because that meant to fix it i had to heat up the iron again, which meant waiting for that to heat up, and then only to solder that one little clip back onto the wire.

Another point was that i wanted a hot air tool as well to do some unsoldering and other odd jobs, and possibly solder or unsolder some surface mount parts. The hot air guns alone were almost as much as the entire station was, so i went with the station and got a fast heating iron with the hot air tool, so it worked out pretty well.

The hot air tool is good for other odd jobs too such as gluing something together using hot glue. The glue gun takes a while to heat up, even when i only have to glue one little thing with it that should take a couple seconds. Using the heat gun i can melt a small slice of a glue stick and glue something within about 30 seconds to 1 minute or even less.
It also works for welding some plastics. The other day i had a drop cloth made of plastic that had a rip in it and that did not like to be glued with any regular glue, so i pulled out the hot air tool and literally welded the rip back together. Took about 1 minute or so. I tried glue but that didnt hold.

 

[Rich D.]

Great idea! I regularly use hot glue because in most cases it works better for my stuff than anything else (I very much dislike CA glue). Bummer though that it takes forever to heat up just for a little dab. Never thought about using my hot-air gun which gets hot enough to melt solder within 30 seconds. Thanks MrAl, you just saved me a lot of time!

 

[DerStrom8]

I have two irons I use regularly:

A 15W (rated) pencil type Radio Shack special (I don't use this one quite as often)
A temp-controlled Weller (never measured the wattage).

Thing about soldering irons is that bigger =/= better. A 60W may not be better than a 40W, in a lot of cases 40W is MUCH too large. My 15W pencil type served me well for many years and works great for small components. The Weller is best for larger components, heat sink tabs, and lead-free solder (ick).

 

[Tony Stewart]

WHen I needed to do a bunch of heavy wire soldering, I used my little propane torch to heat the 30W iron tip to speed up the process.

 

[MrAl]

Great idea! I regularly use hot glue because in most cases it works better for my stuff than anything else (I very much dislike CA glue). Bummer though that it takes forever to heat up just for a little dab. Never thought about using my hot-air gun which gets hot enough to melt solder within 30 seconds. Thanks MrAl, you just saved me a lot of time!

Hi,

You are welcome, just be careful not to ignite anything that could catch fire like cardboard. The melting temperature of regular hot glue is given online so i looked it up before doing this, but i dont remember what it was now...have to look it up again.
It is lower than wood or cardboard, thankfully

 

[MrAl]

I have two irons I use regularly:

A 15W (rated) pencil type Radio Shack special (I don't use this one quite as often)
A temp-controlled Weller (never measured the wattage).

Thing about soldering irons is that bigger =/= better. A 60W may not be better than a 40W, in a lot of cases 40W is MUCH too large. My 15W pencil type served me well for many years and works great for small components. The Weller is best for larger components, heat sink tabs, and lead-free solder (ick).

Hi again,

I guess the way i figured it was that if you have a 40 watt temperature controlled iron and a 60 watt temperature controlled iron, you could use the 60 watt for anything you could use the 40 watt for, as long as you turn the temperature down perhaps and use the appropriate size tip (these kinds have a host of tip sizes and shapes). So for me i would be very happy with a 100 watt model.
I once considered getting a 450 watt model

 

[MrAl]

WHen I needed to do a bunch of heavy wire soldering, I used my little propane torch to heat the 30W iron tip to speed up the process.

Hi Tony,

That certainly sounds like a good idea. I could imagine using the hot air gun too.
I hate waiting for irons to heat up mostly because i usually just have to solder something small that takes like 3 seconds to actually solder. If the iron takes 2 minutes to heat up, it seems like forever.

 

[DerStrom8]

Hi again,

I guess the way i figured it was that if you have a 40 watt temperature controlled iron and a 60 watt temperature controlled iron, you could use the 60 watt for anything you could use the 40 watt for, as long as you turn the temperature down perhaps and use the appropriate size tip (these kinds have a host of tip sizes and shapes). So for me i would be very happy with a 100 watt model.
I once considered getting a 450 watt model

This, of course, is assuming you can turn the temperature down. I guess I just assumed we were talking about pencil types.

 

[Tony Stewart]

The 450 watt models run at the same temperature but massive , intended for soldering stained glass.

 

[KeepItSimpleStupid]

While we're discussing soldering irons, I used a resistance soldering station (tweezers) at work. It's just super-great for doing pins. e.g. a BNC pin. No solder where it isn't supposed to go and it holds the pin. It also had a wire stripping attachment. Really nice for Teflon insulation.

It's always nice to have a Butane soldering iron. It's great for big stuff and can heat shrink tubing. I don't have a heat gun at home.

 

[DerStrom8]

While we're discussing soldering irons, I used a resistance soldering station (tweezers) at work. It's just super-great for doing pins. e.g. a BNC pin. No solder where it isn't supposed to go and it holds the pin. It also had a wire stripping attachment. Really nice for Teflon insulation.

Hmm, never heard of that. Picture please?

 

[KeepItSimpleStupid]

https://www.americanbeautytools.com/ under resistance soldering. You hold the part between the tweezers and push the foot pedal, so your passing a current through the part.

I found that using stainless welding rods for the tips worked well for me. I filed them so they would meet flat.

 

[Tony Stewart]

My favorite soldering iron was the METCAL RF type which use surface temperature sensing material.
I remember at COMDEX in '98 using one for the first time and they had a challenge to remove as many SOIC chips in 10 seconds. I didn't win the contest, but I removed 22 parts .

 

[MrAl]

Hi,

Some interesting stuff coming out here.

Yes Tony, the 450 watt would require a lot more heat conduction away from the joint in order to reduce the tip temperature by say 10 degrees C, while a low power iron needs much less conduction away from the tip to reduce the temperature by that much. So i would be able to solder 12 gauge wires no problem

Matt:
They also make desoldering tweezers, a bit larger, where BOTH tips of the tool get hot and at the same time you can grab the part because of the tweezers action. These are a bit larger than regular tweezers though so maybe for larger parts.
I meant to get one some day but never got around to it, i ended up getting a soldering station instead with hot air tool.
BTW you can also reduce the power of the iron using a small variac. Some of the small ones are much cheaper than the big variacs too. I have used a variac to reduce the power of my soldering gun.

Maybe also interesting is i was able to solder car parts outside by using a small 200 watt 12v to 120vac inverter, with non sine wave output (just the pulsing pattern) using my lower rated 100 watt soldering gun. It was cold outside that day though so it wasnt that easy to solder anyway, but it works, and works better in normal weather. I suspect a small inverter would have no problem with a regular 40 watt iron.

 

[Tony Stewart]

Yes the leaded glass soldering is like 0 guage and takes seconds per joint with hundreds per small glass frame, has high mass and a much bigger tip to stabilize solder temp. He applied heat correctly first and let the solder flow towards the heat.

When I told my buddy John Edwards who ran his Stained Glass business in Winnipeg for decades that the NASA soldering manual taught to techs at Bristol Aerospace where I worked in the 70's was thicker than a phone book, he couldn't believe it. But then I could't imagine him or even me trying to de-solder/solder the center wire in 50 pin circular miniature connector.

What I discovered in wire soldering recently is even with clean parts, brushing on a special active flux paste can really speed up and make more reliable connections to Alum-Clad PCB's for LEDs with tiny pads where the boards is a big heatsink.

 

[Jayson Wallker]

Hello there,


QUESTION #1:
You are shown two temperature controlled soldering irons, one is 60 watt and one is 40 watt. The 60 watt iron is slightly more expensive than the 40 watt iron, but not much more. Which one do you purchase?

QUESTION #2:
You are shown two temperature controlled soldering irons, one is 60 watt and one is 50 watt. The 60 watt iron is slightly more expensive than the 50 watt iron, but not much more. Which one do you purchase?

QUESTION #3:
You are shown two temperature controlled soldering irons, one is 60 watt and the other one is either 40 or 50 watt. The 60 watt looks a little cheaper in quality but not too much cheaper. Which one do you purchase?


If you answered "The 60 watt iron" to either question above, you probably paid too much for that iron because guess what, they are all about 40 watts !!

In various ad's on the web we see 60 watt irons that are the exact same model as the 50 watt irons, yet they are both really only 40 watts. This means they cant solder as well as a real 60 watt iron for somewhat larger metal joints.

First we see the 60 watt rating, which appears in ads for companies that dont seem to care about what they say about their product as long as it sounds good. Then we see the 50 watt rating, where the company is a little more responsible about their rating because they take their rating directly from the heating element which is stamped "50 watts, 24 volts". So we cant blame the companies that advertise 50 watts.

Measuring the DC resistance, we see that the "50 watt 24 volt" element resistance really measures 16 ohms. The power delivered to a 16 ohm resistance with 24 volts DC is:
P=24^2/16=36 watts.

So the elements are not even up to 40 watts yet !

The way it looks is every time the product changes hands the receiver tacks on another 10 watts, so that by the time the ad gets posted it's up to 60 watts in some cases.

That's quite deceptive because we purchase items based on what we need, and sometimes we need the higher power iron but we dont get that, when if we knew the actual rating we would get one that really fit the job.

You'll note that many soldering stations use AC not DC, but that only makes matters worse if there is any inductance because that can only lower the wattage not increase it.

One manufacturer that was contacted actually said that the "60 watts" came form the "input power to the station". But that's not accurate either because the input power with only the iron running is not anywhere near 60 watts. It's also very unlikely that a small control board and transformer would consume 20 watts of power when powering a 60 watt device on full power.
When informed about this, they simply state that you can return the entire station for a refund.

Please note that this doesnt mean that the irons dont work at all, they do, but they wont be as high powered as expected. For example, i had no trouble soldering a #24 gauge (AWG) copper wire end to a 10 turn Bourns potentiometer terminal, which is about 1/8 inch wide and about 1/8 inch long and thin metal. Didnt try #12 AWG wire yet though.

If you have any comments that would be nice to hear, or if you have any experience with these irons. The elements themselves are often advertised as "50 watts 24 volts DC".

A stupid question. What if you were to increase the voltage by 50%? That should increase the wattage/ heat accordingly, if you're willing to sacrifice some reliability and durability of simple soldering iron.

Oh wow, maybe I learnt new thing! Then can I use US version simple low watt devices here with 220V by using just a series suitable diode? Wow we get more power than US! But won't the elements/devices overheated/burnt due to over/double power dissipation?

 

[Jayson Wallker]

Sorry for going back to basic thing, but If element ( iron coil? ) is 110V 25W then if used 220V and a diode to remove one half cycles, then won't it produce same 25W?

You'd be much better off if you used a 1:2 stepdown transformer to obtain 110v, which is within tolerance of the 105-125v North American MAINS voltage standard.

 

[MrAl]

A stupid question. What if you were to increase the voltage by 50%? That should increase the wattage/ heat accordingly, if you're willing to sacrifice some reliability and durability of simple soldering iron.

Hello,

If you increase the voltage by 50 percent then the power goes up by 2.25, so instead of say 40 watts the element would be dissipating 90 watts, which would burn out the element. Elements made for 40 watts can not go much above that or they burn out.

 

[audioguru]

Why do you need to provide more power in a soldering iron? Then it gets too hot and burns the rosin instead of melting it. My soldering iron has automatic temperature control so if its tip gets a little too cool when soldering something that is huge then it automatically turns up the power so that the temperature is correct, then it automatically reduces the power when it is resting.

Automatic temperature control is not the same as using a simple light dimmer circuit like many soldering irons have to adjust the temperature then you fiddle with the power yourself and never have the correct temperature.

 

[MrAl]

Why do you need to provide more power in a soldering iron? Then it gets too hot and burns the rosin instead of melting it. My soldering iron has automatic temperature control so if its tip gets a little too cool when soldering something that is huge then it automatically turns up the power so that the temperature is correct, then it automatically reduces the power when it is resting.

Automatic temperature control is not the same as using a simple light dimmer circuit like many soldering irons have to adjust the temperature then you fiddle with the power yourself and never have the correct temperature.

Hi,

If you really want to know why we might want more power in the soldering iron, try soldering a 4 inch diameter copper sewer pipe with a 35 watt pencil soldering iron. In fact, try soldering a 1/2 inch diameter copper tubing pipe with same iron. Doesnt work. Check out Amazon where you might find a 350 watt soldering iron, which begs the question, what is that for if we only need 35 watts for every application. Sure, wires are thinner, but there are thicker wires too. I once had to solder #6 gauge wire (AWG). I think i did #4 once too and needed a blow torch to do that (battery terminal). Yes it gets hot but if the metal is thick the metal itself does not get as hot, it takes time to heat it up, in the mean time you're applying the solder before it gets too hot, if it ever does.