what temp should my soldering iron be to not melt the board

[ttango]

I have melted the LED pad on two pedals trying to suck out solder. I have never had this problem before. any suggestions? Literally melted the hole shut.

 

[Betty Wont]

It depends on your tip, solder, and technique. I personally run mine at 375c with kester 63/37 1mm with rosin activated flux.

 

[peccary]

It shouldn't take more than three or four seconds to complete a joint. If it's taking longer than that, give that hole a break for a minute and come back to it. A colder iron means more time in contact with the board and components, so running hotter tends to make work cleaner and quicker once you get the feel down. I run mine at 370c. I started at like 345c and kept bumping it up 5-10 degrees over time till I found a heat that worked at my pace.

 

[Cybercow]

Soldering is actually both a skill and an art. We each tend to develop our own techniques and eventually favor a specific type of solder. I don't use a temperature gauge on my iron, I just find the setting, (thru trial and error), where I can get the iron tip on and off a solder point in well under 10 seconds. I've got it down to a point now where I can get the iron tip on and off in ~3 seconds. If I exceed 5 seconds, I back off and wait for the solder point to cool and try again.

And the on/off timing is different for different components. For wiring points, LEDs, photo-couplers, resistors, 'box film'/MLCC/polyester/ceramic & most electrolytic caps, chips/sockets and small transistors I adhere to a 5 second rule. For larger devices/components like pots, reverb bricks, larger transistors (TO-220, etc), switches, and the like, I adhere to the 10 second rule.

Lower tip temps can fool one by melting the solder - but not heating the entire solder connection point enough to allow the solder to easily flow. This can lead to over-heated PCB pads, often-times causing them (the PCB solder pads) to lift/separate.
Higher tip temps can trick us when we leave the tip on the solder point too long and burns the joint that way.

It takes practice and patience. There is also a relationship between the technique and the type of solder being used.

I learned how to solder from the older NASA Soldering Guide. Here is an updated PDF version of that earlier NASA Student Workbook for Hand Soldering. And here's another NASA Soldering Guide. It has some great photo examples. I hope they help.

 

[ttango]

Thanks everyone. I use their 3-5 sec rule as well. Mine was 480 c, so I will back down a bit and try it again..

 

[jwyles90]

Thanks everyone. I use their 3-5 sec rule as well. Mine was 480 c, so I will back down a bit and try it again..

I keep mine around 735 Fahrenheit (387 celsius) and that's worked well for me. That might be on the hotter side of things but you only need to touch the iron to the component/pad for a few seconds to get everything soldered. As others have said, it just takes some practice and patience with it. I bought this solder a while ago and it's awesome. Good quality solder is one of those things that you really don't know what you're missing until you actually try it out. Definitely worth the investment.

 

[Locrian99]

Thanks everyone. I use their 3-5 sec rule as well. Mine was 480 c, so I will back down a bit and try it again..

Yea I ussually keep mind right around 350. Never lifted a pad until this week did twice on the same board. Wasn’t a PPCB board, I’m currently blaming the board lol.

 

[PJS]

You mentioned you were sucking out solder. That is a whole different technique. I must admit I am not necessarily the best at that and so I do find I have to do it in short stints and let it cool between. No matter how tempting it is to just do a bit more and get rid of that last bit right now just take a break, let it cool and then go again.

 

[RetiredUnit1]

I've always used 743f, 395c.... It's the temp the techs at Paramount studios use. My buddy Bob had a job there. Consisted of watching scenes being filmed, and IF something broke he had to fix/replace it. I asked him what he thought of Dr Phil : "OH THAT GUYS A REAL {expletive deleted}

 

[andare]

I can't find 63/37 where I live. Poland is 60/40 only, apparently.

Besides temperature, using the right tip is important. A small chisel tip is perfect for PCBs. 1.6mm-2mm. It allows you to easily make contact with the pad and leads. The default conical tip is garbage. Why include it? It's like soldering iron manufacturers have never soldered in their life.
I use a hoof tip, also good.

Get a bigger tip for bigger components like the back of pots or turrets as that's crucial for heat transfer.

And it goes without saying that your iron must be quick at recovering heat or the tip will always be too cold no matter what you set it to.

 

[Mcknib]

370°C for me

Desoldering I always add solder melt the edge and get my pump right over the joint

If I'm desoldering pots or switches I use my hot air station at around 300°C

As everyone says let it cool if it isn't coming out, even at these temperatures you can still lift pads if you're too aggressive

 

[szukalski]

I can't find 63/37 where I live. Poland is 60/40 only, apparently.

Besides temperature, using the right tip is important. A small chisel tip is perfect for PCBs. 1.6mm-2mm. It allows you to easily make contact with the pad and leads. The default conical tip is garbage. Why include it? It's like soldering iron manufacturers have never soldered in their life.
I use a hoof tip, also good.

I do love me a good chisel tip.

Technically, you shouldn’t be able to get lead solder in the EU without a trade certificate but there are places you can buy without. I recently switched over to Lead solder from lead free and it’s been a revelation.

 

[andare]

I do love me a good chisel tip.

Technically, you shouldn’t be able to get lead solder in the EU without a trade certificate but there are places you can buy without. I recently switched over to Lead solder from lead free and it’s been a revelation.

Leaded solder is readily available here. The only 63/37 I've found is Chinese and I don't trust it.

I have a spool of lead free solder but I've never used.

 

[steviejr92]

370 Celsius. It’s my perfect temp when dealing with 60/40 solder.

 

[szukalski]

Leaded solder is readily available here. The only 63/37 I've found is Chinese and I don't trust it.

I have a spool of lead free solder but I've never used.

EU rules mandate that you can only sell to commercial users, but some countries are more strict at enforcing the law. Germany is probably stricter than Poland in bureaucracy and enforcement. I know I put an extra roll in each order where there’s a place which allows me to order it..

 

[Chuck D. Bones]

425C for me and I work fast. Solder removal is at least 10x harder than soldering. Sometimes I use solder wick, sometimes a solder sucker. The best way to protect the board is to cut the lead(s) of the part and then pull the lead(s) out with tweezers. Sacrificing the part can be expen$ive, so you have to weght the value of the assembled board against the value of the part you're sacrificing.

 

[steviejr92]

At 425C how long are you applying heat approximately?

 

[Chuck D. Bones]

2 or 3 seconds when soldering. I have a medium-fine tip on my iron. The iron's temp sensor measures the temp near the heated end of the tip. The business end of the tip will be cooler, especially when solder is being melted.

 

[steviejr92]

Im giving this a try next time.

I stay within that range now at 370C. I use a chisel tip, i find the surface area applies even heat to both the leg and eyelet.

 

[Chuck D. Bones]

If the pad connects to the ground plane, then it takes more time to get the board to heat up because the ground plane acts like a heatsink.