CTS Soldering Temperature

[Beebe]

I'm wondering if anyone here follows the CTS Pot "Soldering Condition" spec:

Maximum of 250C for 5 seconds.

My 25W Hakko Dash N454 iron temp spec is 450C.

Is CTS giving that spec for the component temperature or recommended iron settings?

Anyone ever measure the temp of the pot while soldering?

I'm guessing most of you will say a 40W iron is fine for general guitar work, or say just don't leave it on there for too long. I'm sure that's true, but does anyone know if holding an iron set to 250C on the back of the pot for 5 sec is sufficient to get a good hot joint?

Edit: The CTS spec is probably for the tabs and not the case. So I'll ask the question for the tabs as well: Does 250C for less than 5 seconds work well?

 

[Kevin Wolfe]

The idea behind the hotter iron theory is that you can get it done faster. Never measured the temp myself and I’ve never hurt a pot that I could tell.

 

[SixStringSlinger]

I've never harmed a pot in any way I can tell (made a mess with the solder, though), with either a 25W or 40W iron. But I did start with a 25W and was concerned about how long it'd have to stay on a pot to heat it up enough, so I went with a 40W because even though it's hotter, that heat has less time to spread to where you don't want it. Now the process is quicker, cleaner and less nerve-wracking.

Again, I never did harm a pot with the 25W. But I don't know how much of that has been down to luck.

 

[Beebe]

Same here.... that I know of. I also have the inexpensive 40W stewmac iron with a fat tip, and I like working with it.

I guess the spec is just to relieve them of liability.

I used to work on miniature surface mount components where I had to look up the temp specs of each device and set my iron accordingly, or they would fry in an instant. It would be nice if CTS gave a realistic spec.

 

[NoTeleBob]

Hot and fast to solder to the pot case. Use a chisel tip.

You can use less heat on the tabs. But if it's a standard 1" CTS pot, I don't see any issues with the 40W and "just enough time" to make the connection. Those are durable. Use more caution on something like a Bourns mini - and especially the ones with the DPDT push pull.

 

[dsutton24]

It's component temperature.

A soldering iron isn't a very efficient heat transfer device. The case of the pot also radiates as it heats. I doubt you could ever get anywhere near 450C by just applying the iron to the pot. Then of course, the pot cools pretty quickly after the heat is removed.

Anyway, I'm the guy who will tell you that you are unlikely to damage a pot with a 25w iron.

There was a thread years ago where the OP tried to deliberately ruin a pot with a soldering iron. It took a looooong time, and some pretty brutal coercion to do it. That's not to say that you can't ruin a pot with a soldering iron, but it does take a lot of determination to do it.

 

[Kevin Wolfe]

Same here.... that I know of. I also have the inexpensive 40W stewmac iron with a fat tip, and I like working with it.

I guess the spec is just to relieve them of liability.

I used to work on miniature surface mount components where I had to look up the temp specs of each device and set my iron accordingly, or they would fry in an instant. It would be nice if CTS gave a realistic spec.

Yeah, that’s it right there. I know from work experience that in the aerospace and avionics industries you would have certified technicians who would have to comply with engineering standards sorta like a welder following AWS specs.

 

[jvin248]

.

You may have a 40w iron but due to contaminants at the soldering iron tip you are just warming the parts. Or you have the technique where you melt the solder+flux at the tip and let the solder heat the wires as it flows into them for a solid connection -- only need a 15w iron to do that.

Back of the pot case you can scuff/sand, heat a little drop of solder there to pool, then put the pre-tinned wires to it, use a little more solder at the iron tip and soak all together with minimal heat -- with a 15w iron from Harbor Freight.

The 'big hot iron' recommendation is just to cut through the contaminants and technique hurdles.


Surface mount components are more tricky and need a proper solder station with heat control and sometimes microscopes to work on accurately. Typical guitar stuff gets done by cowboys every day.




.

 

[Greg70]

I've found that brushing a tiny bit of flux on the joint makes faster wetting which allows for a faster solder connection and less time to heat things up.

 

[old wrench]

This chart below will give you a good idea of the melting temperature of various types of solder -

Soldering Temperature Chart

I've got a Hakko station and I run it pretty hot for pots - higher heat means I can spend less time heating the case of the pot up - it works for me.

Just making sure that the workpiece and the wire are both very clean makes a huge difference in how easy and how well the soldering job goes

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