Wiring question

TheOtherDennis

I bought a kit a while back, finally got round to doing something with it. Inevitably the wiring was cheap, so I bought a kit from Jeremy Charles (which no longer seems to be on sale on his website). I've wired it up the best I can. First issue is that the wires from the pick ups weren't long enough to stretch from the switch to the volume pot (well not without serious surgery, anyway), so I soldered on some extensions and then wrapped insulation tape around the extensions.

I know it's not tidy, I get that. I know it's probably quite clumsy, I get that too.

What I don't get is the rasp when I plug it in that's much louder than the pick ups are. And the rasp isn't even that loud. Is it because I've not grounded it to the bridge properly? If so, how do I do that? I simply cannot get solder to stick to the bridge pins so is that where I should ground it to and if not where and how?

Here are two pictures, one of the cavity and one a close up (apologies for it being out of focus) of the volume pot where Jeremy thought the issue might be.

For guidance, the blue and red wires are the pick up wires, the braided wire is from the wiring kit and was already soldered in; the switch and tone pots were already soldered in, too, before I touched them. The only bits I've done are the pick ups to the switch, then extended the pick up wires with black wire to the volume, then wired the volume to the jack socket.

Does anyone have any ideas or advice for where I've gone wrong? (Please be patient - my wife's having serious health issues and I'm feeling very easily bruised at the moment. I know that's no excuse for clumsiness or ineptness, and I'm not trying to be defensive or rude, apologies if that's how it comes across, but things are bumpy enough for us right now.)

Anyway, thanks for any help.


 

ICBM

You've wired the pickups backwards - the ground connections are the bare shielding (which you have going to the switch terminals) and the white cores are the hot wires (which *should* go to the switch, but are currently grounded).

The wires are easily long enough. You need to connect both pickup grounds to the frame on the switch (hidden under the wire in the pic).

TheOtherDennis

Ok, first up, when I said "the wires weren't long enough without some major surgery", obviously the wires are long enough to reach both the switch and the pot, but it was the "major surgery" I was talking about - if you look at the distance between the switch and the volume pot (which is not down to me, but the pre-wired unit and the positioning of the pre-drilled holes in the kit) it's a fair bit longer than an inch, which is all that was sticking out of the red/blue covering. So I'd have had to slice the red/blue covering by about four inches in order to get the white one to go to the volume and the bare one to go to the switch. I was worried that the two bare wires would touch and thus short each other out or cause some other electrical problem by touching, or that I'd slice through the wires whilst trying to cut the covering to give sufficient play to split the wires that far apart.

Having said that, I've switched the two around which has solved the volume problem without a doubt, so thank you for that (suggesting that Mr Charles isn't all that - I sent him the same pics and he didn't spot that the hot/ground wires were the wrong way round).

However, the rasp is also a lot louder.

This suggests to my ignorant eyes that I am failing to ground correctly. Either I'm grounding to the wrong bit on the jack, on the volume pot or something else. I tried to follow the diagram that came with the wiring kit as closely as possible (hence my mistake in soldering them the wrong way round - that's what the diagram suggested).

In which case, do you have any advice on how to get solder to stick to the chrome tailpiece pin? I assume that's what I ground it to, as there's nothing else close enough, and I had to drill my own hole from the cavity to the pin in order to do that. In case it matters, I'm using an 80 watt Weller soldering iron, so it should be powerful enough.

ICBM

TheOtherDennis said:

Ok, first up, when I said "the wires weren't long enough without some major surgery", obviously the wires are long enough to reach both the switch and the pot, but it was the "major surgery" I was talking about - if you look at the distance between the switch and the volume pot (which is not down to me, but the pre-wired unit and the positioning of the pre-drilled holes in the kit) it's a fair bit longer than an inch, which is all that was sticking out of the red/blue covering. So I'd have had to slice the red/blue covering by about four inches in order to get the white one to go to the volume and the bare one to go to the switch.

No, both wires in each cable go to the switch! The shield goes to the frame, and the white core to the respective pickup terminals. You should only need to strip back about half an inch on each - trust me, there is *plenty* of wire. It's simpler than you're making it .

The same switch frame connection should also be connected to the shield of the braided cable that goes to the volume pot - if it isn't, it should be (I forgot to say to check that) - that's the ground path back to the volume control. You shouldn't need the two black wires that were taped to the pickup wires at all.

TheOtherDennis said:

In which case, do you have any advice on how to get solder to stick to the chrome tailpiece pin? I assume that's what I ground it to, as there's nothing else close enough, and I had to drill my own hole from the cavity to the pin in order to do that. In case it matters, I'm using an 80 watt Weller soldering iron, so it should be powerful enough.

You don't need to. As long as the bare wire runs into the stud hole and is trapped between the stud and the wood it will be fine.

I can't see the wiring on the jack but it's possible you have that backwards too. The centre barrel connection should go to the volume pot casing, and the outer spring contact to the volume pot middle terminal.

TTony

Good to see you back with us Mr @TheOtherDennis ; 

Sad to hear about your good lady - who always seemed to have a smile - and my sincere best wishes to you both.


There are some really easy-to-follow wiring diagrams at SeymourDuncan.com (it's what I usually use when contemplating something new), so if you need a diagram to follow, give that a try.
 

TheOtherDennis

I'm not doubting you for a moment, @ICBM, but just so you know why I did what I did, here's the wiring diagram that came with the kit -



I'll have another look at it in the morning, and maybe at some other diagrams or something. Right now I'm tired.

Thanks for your help anyway.

And thanks, @TTony, pm incoming.

ICBM

That's it, but instead of taking the pickup grounds to the volume pot, take them to the ground point at the top of the switch.

Sporky

Not that he really needs it, but I can confirm that @ICBM is correct, and the drawing you've been given, while electrically correct, is much trickier than it needs to be.

TheOtherDennis

In fairness, I did say that I didn't doubt @ICBM, I merely posted the diagram I worked to in order to show why I believed I had to split the wires in the way that I did, to show that whilst I'm wrong, and I still admit that I am wrong and that @ICBM is righ, there was a reason for being me being wrong, that's all.

ICBM

It's not wrong - the diagram shows 'star grounding', which is best practice for minimising hum - but is unnecessary for such a simple circuit really. The most important thing is to avoid a ground loop, but you won't get one just by taking the pickup grounds to the switch.

The text box about the tone cap is wrong though - in that scheme, neither end of the cap should be grounded to a pot casing or anywhere else, or it won't work!

Sporky

TheOtherDennis said:

In fairness, I did say that I didn't doubt @ICBM, I merely posted the diagram I worked to in order to show why I believed I had to split the wires in the way that I did, to show that whilst I'm wrong, and I still admit that I am wrong and that @ICBM is righ, there was a reason for being me being wrong, that's all.

I didn't mean that I thought you were questioning the advice, just providing some additional reassurance.