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Hey everybody. A friend of mine recently received a Hamer Slammer series guitar that somebody had ripped the volume pot out of it and replaced the original pickups with seymour Duncans. I looked up a comparable wiring diagram to the guitar (the Hamer Californian, with stacked humbucker and regular humbucker config, one volume pot, no tone pot) and followed everything just as it looked in the diagram.

After gettting everything put together, the volume pot isnt working. There's a slight rollback in volume/tone when rolling back on it, but even when rolled all the way off, there is still plenty of sound coming through either pickup (it almost sounds like the signal is diminished, but there really isn't a significant amount of volume drop at all) Very upsetting. For the life of me I cant seem to even think what the issue could be, seeing that its such a simple wiring setup. I thought it was maybe a bad pot (granted, it was brand new in the wrapping and everything) so just to be sure I swithced it out with ANOTHER brand new pot from a different manufacturer. Still the same problem.

Does anybody have any thoughts on what could be causing this issue?

I'm no expert on electronics, but did you put a capacitor in the circuit at the appropriate place?

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"Act your age, not your shoe size" - Prince

Oddly enough, the diagram did not call for one. I checked multiple sites for diagrams regarding the config I was working on (2 pickups, one volume, no tone) and on none of them did it mention anything about a capacitor. I've replaced capacitors before, but never dealt with a guitar with this type of config, so I ran with the idea of "I don't know nuthin, so follow the diagram" so I did not add one.

did you get the wiring diagram from seymour duncan?

http://www.seymourduncan.com/support/wiring-diagrams/

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If trees could scream, would we be so cavalier about cutting them down? We might, if they screamed all the time, for no good reason. - Jack Handey

that is one of the sites I went to (I went to several, including hamerfanclub.com or something like it.....it had wiring diagrams direct from Hamer and followed the diagram for the Californian).

One thing I notice in the diagram on Seymour Duncan's site (2 humbuckers, one volume, 3-way) is the third post on the pot (far right post) appears to be folded over and soldered into a ground. I did NOT do that, and now am wondering if that might be the issue.

Does that post need to be closed? Is that where the issue is, as if there's an open line in the circuit because of this?

Yep,
The open tab of the pot needs to run to ground.
When you decrease the volume, you are in effect shorting it to ground.
I did the same thing this weekend.

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wah
Wah-wah-wah-wah
Wah

For the circuit to operate correctly, one side of the pot goes to the pickup and the other end must be grounded. The center post goes to the output and is now a voltage divider. All the way to the pickup side, the circuit has no attenuation. All the way to the other side, the output is held to ground and you get no volume. If you do not ground the second outer lead you are changing the series resistance to the output but depending on the value of the pot and the input impedance of the amp, very little will probably happen.

ELB

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EddieLee

thank you everybody that posted. I got my handy-dandy soldering gun back out, put the ground to the third post, drove myself to the emergency room, apologize to the neighbors, and voila! Volume knob works just like a volume knob should!

Once again, thank you for everyone that submitted, you helped me out greatly!