Another thread about grounding
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reluctant-builder
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Well, I need long-shaft pots for the Hagstrom, so a full set's going to cost me $30 bucks ($7.50 apiece at GPR). Contact cleaner wouldn't be more than $15, and only if I'm getting extra ripped off, which is pretty much a way of life in New York.
One of the pots is deathly quiet, one is barely scratchy and the others are scratchy enough for me to notice though not exceptionally loud. For grins, I took one of them apart and, lo and behold, the metal band that presses against the track looks a tad bit burnt at its terminals. Gee, I wonder if that has anything to do with zapping the pot casings while soldering to them.
Aside from the crispness, I don't see any obvious signs of dirt, so it looks to me like that toast is the culprit ... and I'd think it makes the pot unsalvageable. Or, at least, unquietable.
One of the pots is deathly quiet, one is barely scratchy and the others are scratchy enough for me to notice though not exceptionally loud. For grins, I took one of them apart and, lo and behold, the metal band that presses against the track looks a tad bit burnt at its terminals. Gee, I wonder if that has anything to do with zapping the pot casings while soldering to them.
Aside from the crispness, I don't see any obvious signs of dirt, so it looks to me like that toast is the culprit ... and I'd think it makes the pot unsalvageable. Or, at least, unquietable.
Cagey
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They also just wear out. They don't make them like they used to. The best pots you can buy are the Clarostat military spec parts, and they're only rated for 25,000 operations. CTS pots are nowhere near as robust, so you can imagine they aren't going to last very long. Not that the CTS parts are horrible - they're better than many - but still. Couple that with the abuse of having their housings soldered to, and it's a wonder they work at all after a couple weeks.
Strat Avenger
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reluctant-builder said:
I run into that problem quite often (and not just with guitar products). I feel the same way.
History Corner (AKA Why are people SO-OO Dumb"):
The "solder to the back of pots" information comes as a direct result of the production-line techniques at Fender and Gibson. It's more efficient to have one person doing only soldering, another doing assembly, another doing setups... The have a little wood block with four (or three, or two) holes in it that hold the pots stationary with a slot or hole for each switch as needed. So one person wires together each "harness" and slides the finished block of parts down to the next guy/girl/production unit, where somebody else plops it into the guitar and attaches the pickup's and output's wires. A "star ground" would add another step, that of somebody who actually knew what they were doing and why. I'm not trying to be snotty here, they're just using basic factory efficiency flow kinds of thinking when they organize the line.
But what it means is that everyone who has ever opened up a great old guitar (or even a crappy one) will find that - the EXPERTS always ground to the back of pots. So you'd better do it too, because of... mojo? The regulations? Because daddy said so! And anytime some guitar tech who knows better wires up a guitar in a more sensible way, the churning masses can pop off the cover and discover that... IT'S WIRED "WRONG!" So the tech has to "fix" it... yet another reason why guitar geekdom OUGHT to be a tax-exempt hobby, because if doing something the dumbass way because everyone else is doing it that way doesn't sound like a religion, well I just don't know. Hummpht. :evil4:
The "solder to the back of pots" information comes as a direct result of the production-line techniques at Fender and Gibson. It's more efficient to have one person doing only soldering, another doing assembly, another doing setups... The have a little wood block with four (or three, or two) holes in it that hold the pots stationary with a slot or hole for each switch as needed. So one person wires together each "harness" and slides the finished block of parts down to the next guy/girl/production unit, where somebody else plops it into the guitar and attaches the pickup's and output's wires. A "star ground" would add another step, that of somebody who actually knew what they were doing and why. I'm not trying to be snotty here, they're just using basic factory efficiency flow kinds of thinking when they organize the line.
But what it means is that everyone who has ever opened up a great old guitar (or even a crappy one) will find that - the EXPERTS always ground to the back of pots. So you'd better do it too, because of... mojo? The regulations? Because daddy said so! And anytime some guitar tech who knows better wires up a guitar in a more sensible way, the churning masses can pop off the cover and discover that... IT'S WIRED "WRONG!" So the tech has to "fix" it... yet another reason why guitar geekdom OUGHT to be a tax-exempt hobby, because if doing something the dumbass way because everyone else is doing it that way doesn't sound like a religion, well I just don't know. Hummpht. :evil4:
reluctant-builder
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OK. Here is my mock up of how I plan to wire my Hagstrom Swede ... it's on the post two down from this one.
I've got new pots, new caps, vintage braided-shield single-conductor cloth push-back wire (whew, that's a mouthful), 60/40 solder and a dream.
The one thing I don't have, that I wish I did have, is a mini-toggle to replace the stock tone-filter switch, but that should be easy to swap out.
I'm trying to avoid soldering to the backs of my pots while, at the same time, getting to ground every connection that requires it. The red wires represent the hot wires, which would be the braided vintage wire, the gray wires are ground wires (whether bus wire or insultated single conductor wire) and the blue dots are solder joints on the braided shield.
Constructive feedback, as always, is appreciated.
My paramount question here is: Does soldering the spare lug to ground on a pot serve to ground the pot, itself? I have my doubts. I expect that I'll need to use the four solder lugs Cagey gave me.
Also, I left out the bridge ground wire.
I've got new pots, new caps, vintage braided-shield single-conductor cloth push-back wire (whew, that's a mouthful), 60/40 solder and a dream.
The one thing I don't have, that I wish I did have, is a mini-toggle to replace the stock tone-filter switch, but that should be easy to swap out.
I'm trying to avoid soldering to the backs of my pots while, at the same time, getting to ground every connection that requires it. The red wires represent the hot wires, which would be the braided vintage wire, the gray wires are ground wires (whether bus wire or insultated single conductor wire) and the blue dots are solder joints on the braided shield.
Constructive feedback, as always, is appreciated.
My paramount question here is: Does soldering the spare lug to ground on a pot serve to ground the pot, itself? I have my doubts. I expect that I'll need to use the four solder lugs Cagey gave me.
Also, I left out the bridge ground wire.
Cagey
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You may have a fit issue going to a mini-toggle vs. the telephone switch that the guitar/pickguard is drilled for. 1/2" vs. 5/16", I think.
Grounding unused lugs on the pot will wreck things. You need to ground the physical pot. So, it's either solder to the pot housings or use the lugs.
Grounding unused lugs on the pot will wreck things. You need to ground the physical pot. So, it's either solder to the pot housings or use the lugs.
reluctant-builder
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http://www.youtube.com/watch?v=w1HKAfaK5uM
I screwed up the diagram. Living in a right-handed world, I wired it according to a right hand diagram, which put the hot lead from the pickups into the end terminal of the volume pot, and everything else was screwed up, accordingly.
As for wrecking things ... how so?
I have my entire guitar gutted. When I want to test something, I hook a test lead to the ground wire of the pup and the bridge ground and hook that to a bus wire. I hook the ground terminal of the volume pot to the same bus wire, and then run another test lead from the bus wire to the ground sleeve of the jack. I hook the pup's hot wire, again with a test lead, to the volume pot, run another test lead from that same terminal to the tone pot's start terminal and, then, run yet another test lead from the pot's center terminal to my cap, which is connected to the bus wire with another lead.
I get no hum, even with the mess of test leads connecting everything. The pots aren't grounded except by the wires attached to their terminals...
Of course, above, I'm describing "Modern Wiring" but, below, I'm depicting "'50s Wiring."
I screwed up the diagram. Living in a right-handed world, I wired it according to a right hand diagram, which put the hot lead from the pickups into the end terminal of the volume pot, and everything else was screwed up, accordingly.
As for wrecking things ... how so?
I have my entire guitar gutted. When I want to test something, I hook a test lead to the ground wire of the pup and the bridge ground and hook that to a bus wire. I hook the ground terminal of the volume pot to the same bus wire, and then run another test lead from the bus wire to the ground sleeve of the jack. I hook the pup's hot wire, again with a test lead, to the volume pot, run another test lead from that same terminal to the tone pot's start terminal and, then, run yet another test lead from the pot's center terminal to my cap, which is connected to the bus wire with another lead.
I get no hum, even with the mess of test leads connecting everything. The pots aren't grounded except by the wires attached to their terminals...
Of course, above, I'm describing "Modern Wiring" but, below, I'm depicting "'50s Wiring."
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Cagey
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You asked "does soldering the spare lug to ground on a pot serve to ground the pot, itself?" and the answer is no. And in fact, you will change how the circuit works, if it works at all.
Think of it this way: there are no "spare lugs" on a pot; only unused ones. But, the unused lugs are still connected internally (not to ground), so you can't just hook them up to whatever you want. It will affect other things that are connected to the pot.
Now, if the pot's housing is grounded, either via ground wire soldered directly to it or through a ground lug/terminal, then if you need one of the pot's lugs to be grounded, you can certainly connect it to the pot's housing to make your circuit. But, you defeat the purpose of using ground lugs if you do that. The object of the exercise is to avoid soldering to the pot's housing.
Think of it this way: there are no "spare lugs" on a pot; only unused ones. But, the unused lugs are still connected internally (not to ground), so you can't just hook them up to whatever you want. It will affect other things that are connected to the pot.
Now, if the pot's housing is grounded, either via ground wire soldered directly to it or through a ground lug/terminal, then if you need one of the pot's lugs to be grounded, you can certainly connect it to the pot's housing to make your circuit. But, you defeat the purpose of using ground lugs if you do that. The object of the exercise is to avoid soldering to the pot's housing.
reluctant-builder
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I understand. I'm certainly not taking any definitive position when I describe my experience with the test lead connections I made. Just that I wired two pots, a pickup, a cap and my jack all together in a way that gave me both sound and no hum, and I did not ground the pot housings in any way that seemed readily obvious to me.
So, ideally, I run a little bus wire to from the normally ground pot lug to the solder lug and then run another wire from the solder lug to my braided output wire, to which the wire to the jack's ground sleeve is soldered. Ah, so.
So, ideally, I run a little bus wire to from the normally ground pot lug to the solder lug and then run another wire from the solder lug to my braided output wire, to which the wire to the jack's ground sleeve is soldered. Ah, so.
Cagey
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There you go. And if you stare at all the physical parts long enough to visualize how they need to be connected, a crafty way of running the various lines will occur to you that'll make it all less work. Might take a beer or two, but that's alright. Beer is God's way of telling us he loves us.
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