Soldering Discussion: At what temperature do you solder switches?

Curious to see what temperature people use. I have a feeling that a lot depends on your solder, your iron, your tip and your exact method. But what temperature do you usually solder at?

I’ve soldered for the past two years at 550F which is about 287C. I use 63/37 solder for easier melting, which allows a slightly lower temperature.

I noticed this on the recent spec sheet for KTT switches:

In the case of using soldering iron, soldering conditions shall be 280℃max

And then I found this on Cherry’s website:

We recommend stations that offer certain features, including, among other things, that the temperature can be regulated by setting the desired value on the soldering station. The required temperature is between 350 and 390 degrees Celsius. It is also ideal if the tip of the soldering iron can be replaced and ESD protection is integrated.

So, what temp do you use?

Also, feel free to let us know what tools or solder you prefer.

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365° C for Sn63/Pb37 22 gauge for me. Wait… that seems off now that I type it. I’ll have to check next time I fire it up!

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Ha. That’s how I checked too. Also I use .8mm which I think is 21 gauge.

This is the solder I use currently:

Kester 24-6337-8800 50 Activated Rosin Cored Wire Solder Roll, 245 No-Clean, 63/37 Alloy, 0.031" Diameter Amazon.com

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For a fresh build (PCB never soldered on & using my prefered solder) I usually set the iron between 300C & 320C, then use the same solder as you @pixelpusher ( Kester 24-6337-8800 50 Activated Rosin Cored Wire Solder Roll, 245 No-Clean, 63/37 Alloy, 0.031" Diameter). Although that can vary wildly depending on the situation. I’ll go much higher heat, like 360C to 380C when doing drag soldering, although you have the buffer of a big glob of flux doing that. Or around the same temp if reworking something with lead free solder. I think what you saw on the KTT website is a combo of two things, them using some of the newer plastic blends which probably have less heat resistance than the usual PA66 nylon used for bottom housings & them covering their butts from someone making a stink if they end up melting the bottom housing a little because of that. In practice what Cherry stated is more true to what you’d really want to do if you have decent soldering technique. IME it’s pretty damn hard to even melt PC with heat transference through the pins. Even if you’re at 400C you’d have to hold the iron on the pin for a good 10 seconds if not more to have that happen.

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I crank up my iron to 350C (I use unleaded solder).
I use a big flat or round end tip to have a good thermal mass.
The combination of temperature and thermal mass allow me to not stay in contact of the switch pin very long (around 2 seconds). Any switch will stay cool after the operation and I can solder a whole board in minutes.

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Hmm. Maybe I am running hot…

I have been soldering at 745F (~400C) for a while now. I also use Kester 24-6337-8800 50 Activated Rosin Cored Wire Solder Roll, 245 No-Clean, 63/37 Alloy, 0.031" Diameter Amazon.com

I don’t think I have any issues. I have never lifted or burnt a trace, but I like that pace that this temp allows.

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I set this temperature once on my cheap Ali express soldering iron about 5 or more years ago when I got into this hobby and haven’t checked it or thought to change it… :joy: always just waited for the little beep that lets me know it’s ready to go.

making me wonder if I should experiment a bit more. Swapping workspaces right now, hoping to get back to building soon and I just scored a $100 credit from dorp keyboard club but most of their stuff is hotswap.

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As long as you’re quick with each joint there really isn’t anything wrong with soldering a little hot. Although 400C is a bit high for leaded solder, maybe give 380C a try. You should still be able to keep the same pace you’re used to from 400C at that & stay within the “recommended” temps. On the other hand it if that’s what you’ve been doing all along it is kind of a “if it’s not broke don’t fix it” type thing.

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I’ve kept mine at 350C and it seems to be a pretty good working temperature.

I’m sure if my soldering was production critical I’d learn the right settings and adjust temperature ranges and such. So far that’s not been necessary.

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Always used to use Kester 44 or 245 in the .8mm leaded varieties back when I did keeb work, and still use them nowadays since I’ve got the spools. Funny enough almost never used an iron with an actual readout on it for PCB work because my $24 Weller clone had a better tip and I couldn’t be bothered to buy new tips for my Hakko. Allegedly the iron went from 150C to 540C, so with the dial mostly in the middle I might have been around 340C-360C.

Haven’t soldered a keeb in a hot minute, nowadays it’s mostly devboards, brushless ESCs, and motors. On my SI012 I’ll go 320C-340C for tht components, 360C for 18ga-16ga wire in connectors, or even 400C for 14ga wires on big copper pours.

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Nice to see you’re still hanging around here, sir.

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I’ve just kept my Hakko FX-888D at the 650°F / 343-ish°C it came with and use thin gauge 63/37 Kester leaded/rosin core. Works well. I use a magnifying headlamp and a light touch with two taps and a two count rest between. I wouldn’t mind a thicker gauge for switches vs. thin for THT components, but I don’t need another roll of solder around at this point.

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Yep, pop in every once in a bit to see what’s cooking. Not done much with keebs in a hot minute other than get Vial working on Budget96 awhile back. I’ve thought about getting back to messing with KMK after doing some actual learning of Python over the summer, but haven’t really had the time with nerf stuff.

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I use a TS101 with a bevel tip and have had great results with Kester 24-6337-0027 63/37 leaded solder flowing nicely and rosin not spitting too much at 335 C.

For lead-free (Kester 83-7068-1402) I dial it up to 375 C. This all come from Kester’s own data sheets, so I trust them as they’d know best :wink:

Process Considerations

Solder iron tip temperatures are most commonly between 315 to 343 °C (600 to 650 °F) for leaded alloys and 371 to 400 °C (700 to 750 °F) for lead-free alloys. Heat both the land area and component lead to be soldered with the iron tip prior to applying the solder wire to land area or component lead. Do not apply the wire directly to the soldering iron tip; doing so will shorten the life of the soldering tip.

Whether you choose to use regular or lead-free solder, ALWAYS make sure that you have a fan or fume extractor going because it’s the flux that is in the fumes that are harmful, and not lead.

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With my HAKKO FX-888D, T18-DL2 tip and Sn60/Pb40 wire I normally set temperature at only 250C without any issue.
It seems like mine is a much lower temperature than yours… :sweat_smile:

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That’s close to what I run but much lower than most. I use the same iron with a T18 tip.

I used to solder at higher temps but the I started playing around a few years ago to dial in a temperature that worked for my setup and my solder that would be fast but also as gentle as possible.

I started at around 350c (650F) and lowered the iron temp a few notches at a time. Landed on 287c or 550F as a temp where the solder melted instantly and the joint could be flowed in about 2 seconds.

I definitely desolder at a higher temperature than soldering. I want everything as hot as possible when I squeeze the suction trigger on my FR-300.

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I do 350C for 63/37 No Clean Kester solder. No splatter or anything messy if you work close to the joint with no sudden movements. Also on a Hakko FX888D

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From your last link, interesting, I hadn’t realized:

The 63/37 alloy is Eutectic meaning it melts and solidifies at the same temperature. This drastically reduces the likelihood of a cold solder joint since the range between solid and liquid is virtually non-existent.

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I also solder at 350 without any issues or mess. You know how you get into a rhythm when soldering? I find that having a hotter iron is more accommodating of that groove.

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Hakko FX-951 for soldering, FR-301 for desoldering, FA-400 fan. 700F (~370C) in both cases - like @sarvopari, I like to get into the flow, and find that the higher temps just make it easier for me to get there.

Kester no-clean 63/37 is my jam - 0.031" gauge for switches, 0.02" gauge for smaller things (USB ports, LEDs, the occasional SMD component, etc.) I use chisel tips in both cases, but I’ll use a slightly smaller one for the 0.02" gauge.

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