Temp. vs. wattage in soldering. Which do I need?

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For decades of service work I, along with most other bench techs, have used the Weller WTCPT soldering station.
I refuse to use anything else.

If you tried a Metcal you wouldn't touch the Weller again. I have 2 Wellers in the garage that I used to use religiously like you but after trying a Metcal the Wellers went to storage.

The Metcal heating element is also the temperature sensor and it is in the front end of the tip. The Weller heats from the rear and senses at the opposite end of the tip. It was a great advance in the '60s but there is MUCH better now.

IIRC my Weller took 30-45 seconds from a cold start. The Metcal is ready in 7.

A used Metcal is around the same price as a new WTCPT.

I can solder and desolder things with the Metcal that you wouldn't even try with the Weller because it doesn't have the power.

 
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If you tried a Metcal you wouldn't touch the Weller again. I have 2 Wellers in the garage that I used to use religiously like you but after trying a Metcal the Wellers went to storage.

The Metcal heating element is also the temperature sensor and it is in the front end of the tip. The Weller heats from the rear and senses at the opposite end of the tip. It was a great advance in the '60s but there is MUCH better now.

IIRC my Weller took 30-45 seconds from a cold start. The Metcal is ready in 7.

A used Metcal is around the same price as a new WTCPT.

I can solder and desolder things with the Metcal that you wouldn't even try with the Weller because it doesn't have the power.



All well and good.
However, it sounds like your a salesman for metcal......LOL!
I am not in such a rush to have to wait for a trivial 30 seconds for my Weller to heat.
What's the rush?
After using a WTCPT since the 1970's, I doubt I'd change, besides, my station is new, only 2 years use.
 
Now, my question is, does an iron with higher wattage but similar or even lower temperature melt solder faster in the same situation, all else being equal? I ask because I was thinking of getting a Goot px-201 iron, which has a max. current rating of 70W and mostly excellent reviews
Good universal professional soldering stations usually are 60-70 W (or a little bit more).
And yes - for example T12 station typically can work with lower temperatures than cheap ancient ones (hakko 900 type).
 
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Weller

Personally I haven't found a better soldering iron station than the Weller types.

I'd check the tip. What number is marked on the back side of the tip? 7? 8?

From what I know, most Weller iron tips are heated by induction, there isn't thermostatic action, other than what ths tip provides. A 7 tip heats to 700F etc. I've never had to use an 8 tip unless soldering lead free or high temp solder. If a 7 tip isn't cutting it, and an 8 still not enough, then the iron must be defective I guess.
 
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Personally I haven't found a better soldering iron station than the Weller types.

I'd check the tip. What number is marked on the back side of the tip? 7? 8?

From what I know, most Weller iron tips are heated by induction, there isn't thermostatic action, other than what ths tip provides. A 7 tip heats to 700F etc. I've never had to use an 8 tip unless soldering lead free or high temp solder. If a 7 tip isn't cutting it, and an 8 still not enough, then the iron must be defective I guess.


Weller stations like the WTCPT use tips surrounded by a heating element, not any induction..
Once the tip reaches the set temperature, (6-7-800 F) the magnetic properties of the tip change, causing an opening of the switch that powers the heating element. - this is due to the calibrated magnetic "slug" at the bottom end of the tip and stamped with the temp number (6/7/8)

This system is highly reliable, as these stations have been used on assembly lines for decades, as well as tech service benches.
I've used the WTCPT on my service bench for decades as well, of course, because of its reliability.
 
Yes I misunderstood how their thermostatic operation works

I have both types

Tiny short tips, and stamped slug in the end of the iron. Modern Weller.

Long tips stamped at the ends, same heating system, just the slug is on the tip and not the iron. Old Weller.

FWIW the RS stations use the same type of tip as the modern Weller, but a normal element, thermistor controlled.

Try as I might, I can't use the modern Weller for very long, and switch to the old Weller or RS in quick time. The only real problem with the old Weller is the 1" needlepoint tip doesnt heat well, and they're easily bent (usually helps in soldering anyway)
 
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The Goot PX-201 is rated at 70watts, the Weller rated at 25watts would have trouble melting a stick of butter.

I have an Antex 30 watt iron and it even solders heatsinks.
The solder melts instantaneously as soon as I touch it on the pad and iron.

The screw holding the bit in came loose once and that affected it a lot.
Bad/old bits can perform poorly.
Wrong type of solder also is bad.

I went through a couple of soldering stations quickly before I just opted for the cheap Antex iron.
Had it about 5 years now with no problems.
 
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Temp. vs. wattage in soldering. Which do I need?

Both plus enough mass to to transfer heat into the parts to be soldered.

A little teeny tiny needle tip will never solder a heatsink to a PCB no matter hot or how many watts.


The thing you need to undestand is....
There are different types of soldering irons and stations.
And, depending on the job, it would require a specific type of iron.
So, in order to be properly equipped, one must have several on hand.


Soldering directly to a steel radio or tube amp chassis would require a 100 watt iron with a sizable 1/4" or larger tip.
But soldering an IC on a pc board would only need a 25-35 watt station.
Larger components may need maybe 60 watts, and a larger tip.
Thus, a vari-temp iron would be the choice there.



There are no "one size fits all" irons.
 
I haven't read the thread but when I see the OP's question all that comes to mind is Metcal.

Once I got mine I stopped thinking about all of that stuff. Solder an 0201 part (which I did just last week to repair my laptop) and then solder a penny to a chassis, all without thinking about any settings, just change tip and go.
 
I haven't read the thread but when I see the OP's question all that comes to mind is Metcal.

Thermaltronics is similar to Metcal, I think both spun off from the same company originally. These are different and newer technologies. You should read about them if you are able.

Thermaltronics TMT-2000S-PM Soldering System w/SHP-PM 100-240VAC interchangeable for Metcal MFR-1110 - - Amazon.com

I think I have this one. While they say these "instantly" heat up, it takes a few seconds. It is pretty slick technology and works well.

Sorry have not heard of Goot.

I think its the temperature not the wattage, unless you have something big to solder, then its both plus size of tip (use a big one).
 
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Thermaltronics is similar to Metcal, I think both spun off from the same company originally. These are different and newer technologies. You should read about them if you are able.

Thermaltronics TMT-2000S-PM Soldering System w/SHP-PM 100-240VAC interchangeable for Metcal MFR-1110 - - Amazon.com

I think I have this one. While they say these "instantly" heat up, it takes a few seconds. It is pretty slick technology and works well.

Sorry have not heard of Goot.

I think its the temperature not the wattage, unless you have something big to solder, then its both plus size of tip (use a big one).
A small warning. I have found Thermaltronics tips are sold as cheaper alternatives, physically identical to Metcal and slot in OK, but are not accepted by my Metcal system which refuses to heat them. I just bought Metcal tips and moved on.

I have not used a proper Weller, but rather a slew of cheap soldering irons and stations before taking the plunge with a second hand Metcal. My goodness I'd never, ever, go back!

The near instant warm up is a time saver when changing tips (it's a ten second job to swap tips and be at working temperature again), what's fab is the instant heat delivery right at the tip. Even tiny smt tips can solder way above their size, whilst my 1/4" chisel solders really beefy material. It speeds up the soldering process, an absence of questionable joints, and presumably that suggests less stress being placed on components?
 
Temp. vs. wattage in soldering. Which do I need?

Both plus enough mass to to transfer heat into the parts to be soldered.

A little teeny tiny needle tip will never solder a heatsink to a PCB no matter hot or how many watts.

I'll say it again. Try a Metcal and you will not go back. I HAVE soldered a heatsink to a PC using a 'teensy' tip, specifically an STTC-126 like this

STTC Soldering Cartridge, Conical

That tip is excellent for clearing solder out of the holes in a PCB and if you ever tried on a motherboard with no thermal relief in the board, you would get it.

I used a tip like that to re-install a PEM on a broadcast VTR that had been pressed into a light gauge steel chassis but was carelessly popped out by another tech. When the older melts on the other side of the steel you know it's hot enough. At the time that was a $110,000 dollar machine so you really don't want to bung it up.

For either of those tasks a Weller would not have done the job. I would like to try a JBC iron as I have heard good things about them but you don't find used ones on eBay and I really don't want to drop $500 just to try one.

 
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