Best Practices for soldering PCB?

[Mars Hall]

I have a Blues Jr. that I'm going to install some mods on. All of my experience is with PTP boards. I know PCB's can be fragile and prone to over heating, that can destroy the tracing. Can someone please advise on some best practices?

My first attempt seems the solder joints are cold and the solder runs up the lead towards the iron. I've been keeping the heat to the lead only but it doesn't want to bond. I'm using a Weller WP35.

[demonufo]

You will find that you have to heat the traces as well as the components.
Modern PCB's are anywhere near as bad for lifting as older stuff.

I prefer to use a larger, hotter iron, but with a finer tip, and work fast. Use a tiny bit of solder straight away to help 'heat soak' the lead and trace, then wait a couple of seconds before applying solder properly. As soon as the solder flows quickly get straight out with the tip and the solder at the same time. Unfortunately you'll need to experiment a little to find out just how long you need to leave it before applying the solder, but as long as you're using a good iron that makes a good contact, you shouldn't be lifting traces.

I have no idea what you're weller is like, but I use a 50W temperature controlled Antex, flat out, but with a tip that is only 2 - 2.5mm wide, therefore isn't deathly hot, like it is when I fit a really large tip to it (that's the beauty of Antex irons, good price, and really simple slip-on interchangeable tips).


My big tip is to be careful when de-soldering, rather than resoldering. This is where most of the problems occur. For the initial big blob of solder, use a solder sucker, then put that thing down. They're not the best of tools. Finish off the job with some good de-solder braid/ solder wick. The Chemtronics stuff is nice if you can get it. Basically, you need one that is properly impregnated with flux, preferably "no-clean" type, and a wick that is not too big for the job. Otherwise you'll need a bigger iron and risk damaging the board/components.
Just put the wick against the joint, iron on top with enough pressure to heat, but not so much that you can't tease the wick through when the solder begins to flow into it.

Pretty basic stuff, but very easily overlooked.

[Mars Hall]

It seems to me the holes made for the leads are just big enough for the leads. The solder is able to seep through to create a good joint?

[demonufo]

If you're struggling to get solder to go where you want it, it's worth trying some flux paste on the joint first, and then soldering. Just a smidge, mind you.