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So I recently finished my first build and I am trying to wire it for the Seymour Duncan vintage blues pickups with a 3 way toggle switch. I followed the diagram and set the whole thing up but when I plugged in in I got no sound just the hum. So today I took it all apart and resoldered everything but I still only get a hum and no sound. I took pictures my process step by step in this album http://m.imgur.com/a/dQxcp. I not too great with electronics so there is a good chance I missed something. I think it might be a short somewhere but I don't know how to find it. Could it be the conductive paint shielding? Any help or suggestions would be greatly appreciated! Thanks!

If you haven't already done so, use a multitester to confirm that all your connections are true and for shorts.

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A couple of questions. Is it the same in all three switch positions and at all settings of the volume controls? if you tap on the pickup with a screwdriver to you hear anything at your amp?

Squinting at the pot wiring it all looks OK but its pretty hard to tell. What I don't see is the switch and the jack (one photo, hard to see). Make sure the center two terminals on the switch are tied together and go to the tip pf the jack. Sometimes its kind of hard to tell which terminal is the tip and which is the ring (which is grounded).

I'll also add that it is often difficult to find a short with a multimeter since you'll have all sorts of back feeds thru pots and pups - its often necessary to unsolder something to check it out.

Last dumb thought (it happened to me) - does your amp cable plug go all the way into the jack and make contact with both ring and tip? I had one where the recessed jack plate didn't let my particular cable go all the way in - drove me crazy.

Not to bash as I'm not that wonderful with a soldering iron, but several of the pots have what we used to call "loose solder". IE, a build up of solder on either the wires or the back of the pots, tangs sticking out, etc. Generally the result of a gun not hot enough to actually melt or "flow" the solder well. I'd check for some shorts in that and see what you come up with.

All 3 switch positions yield the same results, no sound just the hum. If I tap the pickups with a screw driver I get a slightly louder buzz. I'm fairly certain I got the terminals on the jack soldered correctly but I don't know if the jack is going in all way. I made another album with images of the jack and the 3 way switch for reference http://m.imgur.com/a/cBBZD. Would it be worth getting a multimeter?

Borrow one? Use resistance (ohms) and check for 0 where circuit should be and 1 where circuit shouldn't be. If you have a decent one, you can even check the capacitors.

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James,

Never mind. I see now Freeman mentioned the output. Easy mistake to wire the ground to the tip lug -especially using same colored wires.

Your picture is a little weird looking - it looks like the tip (center) of the plug is on the wrong side of the part of the jack that makes contact. Here is a new jack and plug



You can see how the S-shaped part of the jack fits into the recess at the tip of the plug (thats actually what holds it in place). In your picture it looks like its on the wrong side and also the plug isn't all the way seated into the jack. The "ring" part of the jack contacts the barrel of the plug.

Next, when you look at the jack itself to determine which terminal is tip and plug. On my jack the right hand terminal as you look at this picture is the tip, the left is the ring. Some jacks have additional terminals (a stereo jack or one with as switching contact)



A multimeter is a valuable diagnostic tool as long as you know how to use it. You can check continuity (open or short circuits) as well as the actual resistance of some part of your circuit, but it is also very easy to be fooled - for example you might be checking continuity but actually reading back thru a potentiometer or pickup (which should give you a finite resistance reading but can be confusing).

Last comment, let me be nice. Some of those solder joints are pretty sloppy looking and are what we might call "cold" joints. Good joints are nice and shiny and the solder is a smooth blob - here is a LP cavity with good joints

Its always a good idea to use a shielded wire to the jack - the core is the "hot" wire to the tip, the shield is the ground to the ring. Sometimes you'll have a separate terminal for the ring and another ground for the body of the jack - that lets you "float" the ring if you want to. In that case I would still use shielded wire for the ring and tip and a separate ground wire to the body/plate.

One more thought (for the next guitar). I try to do as much wiring as possible outside the guitar. I'll make a mock up with cardboard or something with all the components in their position - wire as much as I can (usually you can't complete the switch or pickups but I'll connect them temporarily.



Plug it in to an amp, tap on the pups with a screw driver, make sure everything works (pots go the right direction, ditto switch) It is so much easier to trouble shoot out of the guitar.