How do you solder to the back of a pot?

[SEAN RAF]

I don't do wiring that often, and now I know why...how do you solder to the back of a volume pot? I can't get the earth wires to stick, any ideas? Grateful for any help, I've got 3 guitars to do!
Cheers
Sean.

[jackson1]

Take an exacto knife (or sandpaper) and scratch the surface good. Don't touch it with your (greasy) fingers. The now exposed metal-surface will accept your solder like candy is accepted by a little boy.

Pre-solder the wire and the pot before joining them. When ready to join them, hold your iron to the pot and heat it up (few seconds).. while holding the iron there, place your pre-soldered wired to the spot. Remove iron, hold the wire steady and blow (to cool).

[Sunbane]

Plus the pot needs to be hot enough to properly melt the solder. If you use an iron with too low wattage, that will take time, and you risk damaging the pot because of long exposure to heat. Use a soldering iron with at least 25W of effect - preferrably more.

[straycat]

Just touch the iron to the pot and get it warm, touch the solder to it and it will form a small pool of solder lift the iron.put a little solder on the wire end and lay the wire on top of the solder on the pot and touch the iron to the wire and it will "melt" into the pool on top of the pot.You don't need much solder to make a good connection.

[Chad]

...and blow (to cool).

That's a soldering no-no because it can cause cold solder joints.

[jackson1]

If by pool you mean like a drop of water on a waxed car, you're about to make a bad soldering, with very bad connection to the underlying metal.

straycat, when i read your advice again, it really sounds like a recipe for a bad solder job. I'm an electronic engineer and i hope i can comment on this, without sounding like an ass. I'm not dissing you, bro - i'm just helping out Your job will have a good wire-to-pool connection and a lousy solder-to-metal connection.

Cleaning the metal is essential. Then use as little solder as possible, leaving the surface of the wire visible, would be the correct amount of solder. A 40 watt soldering iron will fit this job.

EDIT: Chad, maybe i don't blow that hard after all. All my solder jobs are shiny and not dull.

[straycat]

I ment a small pool not like a drop of water.This makes a solid connection between the pot and wire and a very visualy clean joint.Not much solder is used.I heat the pot touch the solder when the solder starts to run I move the tip around to spread the drop out a little like a skin.Pool I guess is the wrong term.
jackson 1 I take no offense at your post I see your point and I have done fine point soldering as well ie printed circuit boards and can solder with the best of them.But I have found when soldering guitars(to me these are large soldering items) this makes a very solid connection.Oh and I do prep the pot before soldering I am anal when it comes to a clean connection.

[OldSchool]

Saen Raf, Re-Read Jackson 1's posts and you will be fine. A 40 watt soldering iron is Min. I would use on the pots and ground wire to the spring bracket, everything else on the guitar a 25w is fine.

you do not want a cold solder joint! (((Murphy's Law page 128, section B, it will fail on you when you most need it to work)))

[jackson1]

Here's a picture reference:


V This is how a good solder connection should look - clean, shiny, and just the right amount of solder.

X A bad solder connection - too much uneven solder which is all pointy and indicates that the joint has probably been overheated.

X An even worse solder connection - note the uneven texture, and the flux remaining on the joint.

[Bengal65]

Another little trick that aids in the solder's flow is using some liquid rosin for soldering. Use a pipette or Q-tip to put a drop on the pot you are soldering to before heating. Works great and the solder really flows!