Soldering Problems

[ranchak]

I etched some boards about a month or so ago. After etching I washed them in soap and water and leave the PnP residue on. When I am ready to use the board I drill it and wipe off the PnP residue with Xylene. My problem is that the solder doesn't want to stick. I am using a 25watt soldering iron. I thought maybe I should try a bit more heat so I bought a 40watt iron. I'm still experiencing the same problem. Anybody else have this problem? Any cures? Applying a paste flux to the board before soldering? Cleaning the board with toilet bowl cleaner? Ajax cleanser?

[boogietube]

I always clean the traces with 0000 Steel Wool before I solder.

[darron]

there shouldn't be a need for additional flux. getting solder to go where you want it to can be a bit of a trick. brush your board down first, use a bit of metholates spirits, or ethanol to clean it down. don't waste your vodka though...

correct technique just about always solves this problem. solder is controlled to go where heat will go, so if your iron is hotter than the copper board, the solder will just stick to your iron. i think correct soldering technique is something that REALLY should be taught here. maybe wit ha video example?

HERE'S THE TRICK:
Put your component it it's place. On one side of the component, hold your iron between the copper board and up against the leg of the component. Leave it there for a moment (keeping in mind that components WILL fry if you overheat them, but it's it not even hot enough to melt solder yet then don't worry   )

Using your other hand (no the coordinated one I prefer), press a length of the solder on the side where the iron isn't, into the gap just between the component leg and the copper board. When the copper is hot enough the solder will quickly melt and surround the leg of the component. Remove the iron as soon as you have the situation under control.

I think I'll try to make a diagram to help explain this to people better and post it. Give me a little while and I'll begin now.

[darron]

I've prepared a video tutorial, as promised:

http://www.diystompboxes.com/smfforum/index.php?topic=51606.0

[Thomas P.]

I etched some boards about a month or so ago. After etching I washed them in soap and water and leave the PnP residue on. When I am ready to use the board I drill it and wipe off the PnP residue with Xylene. My problem is that the solder doesn't want to stick. I am using a 25watt soldering iron. I thought maybe I should try a bit more heat so I bought a 40watt iron. I'm still experiencing the same problem. Anybody else have this problem? Any cures? Applying a paste flux to the board before soldering? Cleaning the board with toilet bowl cleaner? Ajax cleanser?

For cleaning the board there is no need for soap. Just cold water is enough.

- What kind of solder do you use?

Another clue might be how you solder: Make sure you heat the pad as well as the leads!

[ranchak]

I use the technique described by Darron. I have no problem with a fresh board. I believe that the problem is surface oxidation from sitting. I will try cleaning the board with steel wool and see if that helps. If I have to I guess I can tin the board before I populate it.

[Cardboard Tube Samurai]

As soon as I have etched a board, I wipe the PNP off with Mineral Turpentine, then wash that off with Methylated Spirits. If the board is going to sit for a while before I solder, I give it a coat with Contact Cleaner/Lube then clean that off with Metho before use. Never had a problem with solder not sticking properly

[Paul Perry (Frostwave)]

I prefer wire brushes to steel wool - and with steel wool bits can break off & be a potential short.

[ranchak]

I tried the steel wool and that definately made a difference. I think I will try either a Scotchbrite or a brass brush next time.