Metropoulos Forum

hey guys, doing some tweaks on a 70's marshall PCB. until now i've only soldered on turret board. i don't want to destroy any of the connections on the board putting in new parts, i've had some bad luck in the past with boards in pedals, etc. any good advice on how to approach this and do it right? i never really learned the right way to solder other than 1.) make things hot until they melt, 2.) repeat. help me get this thing rocking.

ziggie

I am far from an expert but I do have an expert tip. For people like me an you who rarely solder anything, find some electrical POS and tear it apart. Use the old electronics board to practice on before you attempt any soldering. This way you have a high confidence level if you have just been practicing for 10 min before you start your project. Also, I purchased a Solder sucker from Radio Shack for about $15 and it works awesome. I couldn't handle working with braid but the solder sucker makes it easy. Good luck!

ttowne wrote:ziggie

I am far from an expert but I do have an expert tip. For people like me an you who rarely solder anything, find some electrical POS and tear it apart. Use the old electronics board to practice on before you attempt any soldering. This way you have a high confidence level if you have just been practicing for 10 min before you start your project. Also, I purchased a Solder sucker from Radio Shack for about $15 and it works awesome. I couldn't handle working with braid but the solder sucker makes it easy. Good luck!

+1

Only things I'd add, is if you have to buy a solder sucker, you might want to look for one that has a guard beside the plunger. They are a bit more of a PITA to press down and cock than the open kind, but they save you from nailing yourself in the face with the plunger when you're using it.

I usually use the SS first, then some solder wick to clean up if needed. Depending on the PCB, soldering might loosen the trace some, so make sure the hole is clean so you don't lift and tear the contact pad when you slide in the replacement part.

+1. Desoldering iron. I use that thing more than I ever though I would - even with turrets.

They also make pen-type suckers. No heat, though. Very accurate, but you need to touch it with a soldering iron first, then get the pen sucker on there. I don't like the transfer, but the pen is good for tight spots, and some prefer it. I prefer the full desolder iron.

If you heat the conection too much, it's EASY to remove the pad from the board, so be careful. I'd be lying if I didn't say I didn't have to run wire for a pad I destroyed - but that was pre-desolder iron.

thanks guys. good advice. i've been practicing with the solder sucker and it's getting better. rock on.

be carefull when putting new components/resistors in, they might have bigger/larger leads than the previous and you might "unglue" the traces
ie they'll go through the pcb hole (above) but push the trace off of the pcb (unduneath)
this has happened to me several times on an old pcb (70's)
I've learned my lesson the hard way

Wattever wrote:I usually use the SS first, then some solder wick to clean up if needed.

And it usually is with stubborn PCB's. Beware though, there is wick, and there is wick. Make sure you get stuff that is well impregnated with resin otherwise it is next to useless in practice. I'd get a range of small sizes. You go much over 1.5mm wide with wick and you need a lot of heat to soak up the solder, which is where the problems begin.

thanks guys.... i'm getting a lot better. nothing worse than melting off a pad on a pcb.

also.... wondering what will happen if my wire gauge is too small. i'm not sure if it is, but what is a recommended size for amps? using some multi stranded stuff from radio shack, i thinks its 22 awg, 300v. assuming signal might be a little weaker..? any suggestions on what to buy?

hi.

Soldering PCB's are not a big deal ! Practicing will make you perfect and proficient in it . Although Theory is also necessary !

If you are new to soldering then check your approach ; whether are you stick on too much until part gets burned or just pick up before it gets properly soldered !

If you belong to group of first category use soldering iron between 30W to 40W ; and for the second use 40W to 65W Soldering Iron.

Use sharp tip soldering iron instead of flat tip ! Use Resins and flux . They will properly distribute heat and ensure good solder joint !

Thank you

Hmmm, never noticed this necrobump just to promote your spam link.

I can't help but disagree with your comments either. Wattage of the iron can be absolutely irrelevant dependant on the size of the tip. With one of my Antex irons I can bring the temperature right up or down depending on the size of the tip, when not using my solder station. And as for using a sharp tip as opposed to a flat tip, maybe if we were talking about modern tiny components, but guitar amps are a lot more archaic than that in general, and a decent shaped single faced bit will work far better for what we are working on here.

Antex!!!! I use 18 watt!!! Never had a problem with it. Grate for Guitar FX and Amp build.

Is a 60watt iron too much for PCB?
I actually burned one part on my board and solder wouldn't stick to it
Luckly I soldered it on another hole further down on the board.

And I didn't touch it long either


Thanks !

Buy an adjustable temp soldering iron/station (Weller, Hakko, etc.). Anyone using a non heat controlled iron is not doing the correct thing (at least as I was trained as a military contractor). I have used them myself, and you can do a good job with one, but you get a much more predictable outcome if you know that tip is within a few degrees of what you set it. I set mine to 700 degrees F. The trick is to get the heat on and off quickly. It's better to remove the iron if you can't get heat transfer and whetting quickly. Let the joint cool down, then reflow instead of just continually applying heat. That is when damage occurs.

I looked around for a soldering tutorial, and found this: http://www.ladyada.net/media/common/soldering.pdf I scanned it briefly, and it looks pretty good.

AJW wrote:Buy an adjustable temp soldering iron/station (Weller, Hakko, etc.). Anyone using a non heat controlled iron is not doing the correct thing (at least as I was trained as a military contractor). I have used them myself, and you can do a good job with one, but you get a much more predictable outcome if you know that tip is within a few degrees of what you set it. I set mine to 700 degrees F. The trick is to get the heat on and off quickly. It's better to remove the iron if you can't get heat transfer and whetting quickly. Let the joint cool down, then reflow instead of just continually applying heat. That is when damage occurs.

I looked around for a soldering tutorial, and found this: http://www.ladyada.net/media/common/soldering.pdf I scanned it briefly, and it looks pretty good.

Thanks man!!

that was pretty good.
knew most stuff. but still had great info in one package

cheers!