1/3 less vol in bridge pickup

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:help:  I'm stumped on this one ….  :icon_scratch:

It's my Blue Quilt Strat in process ... well it's kind of finished ..... But  :toothy11:
I put in 2 Seymour Duncan Humbuckers with 1 Vol & 1 Tone & basic 3 way strat switch.
Wanted the basic setup…

What I have in the Neck is the (Jazz) is great sound & works fine in one & two position.

The Bridge is a JB & it's got about 1/3 rd less vol / punch to it…. This can't be right !!!

OK … I've tried another SD hum in the bridge, a Custom 5 & the same thing happened !!

I even tried the JB with the different wires soldered together (just to try) ie: Green & White …. NOPE, DEAD.
Went back & tried Original wiring …. still 1/3 rd less power / vol

:icon_scratch:  Pickup is as high as I can go….

The Vol goes from 10 Full Vol to 9 OFF NO Vol …. I'm using the CTS 500 Audio Taper Pots.

Have I killed the Pot ?  :sad:  & is this affecting the Bridge pickups lack of volume ?  :toothy11:

Switch is wired like so (top right)… http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=3ws_trans

Many Thanks  :icon_biggrin:

WTF  :doh: why can I do harder wiring setups & completely stuff up a BASIC wiring setup.... I'm slightly pissed off

 

[TroubledTreble]

Can you post a pic of the control cavity?

Do you have a way to check resistance on the pickup? Green/Red screw side bobbin, Black/White slug side bobbin. I can't help but wonder if one of the connections is bad.

Also can you just wire the bridge pickup straight to the output, this would tell you whether it's pickup or control related. Divide and conquer!

 

[Updown]

Will try for some pic's tomorrow

Yep got a meter  :icon_scratch: just gotta work out what to do & how the  ///// thing works to check resistance.
Is there a easy way to explain how thats done  :toothy11:  ..... I know Google it !!

I may just try some other Pots & just do a new Rewire Job. .... But would like to test the resistance 1st thou....
Never happened before, was really hoping it wasn't the pickup, hence trying the other one.

Thanks  :icon_biggrin:

 

[TroubledTreble]

Put the meter in the 20K range and try not to touch the leads with your fingers when testing. In the 20K range your fingers should not affect it but it's a best practice.

Test each coil separatly and also check between each lead and the baseplate. Against the baseplate you should have an open circuit (no reading). If it is the pickup it may be repaired.

 

[Updown]

Heres some pic's... Please excuse the little messy side of things, but I'm trying to get this right.
Haven't metered anything as yet !!
:icon_scratch: Might try again with different 3 way Switch & Pots ..... Because the wiring is as it's meant to be !!!

Red & White ...Soldered together  :icon_thumright:
Green & Bare to top of Vol Pot / Earth  :icon_thumright:
Black wire's to both ends / either side of 3 way switch Switch  :icon_thumright:
Yellow wire to vol lug then to tone pot lug  :icon_thumright:
White / Live coming off vol middle lug, to output jack :icon_thumright:
Black Earth coming off Tone pot, to output jack  :icon_thumright:
Both Pots connected by Black wire Earth (& other lug to vol pot)  :icon_thumright:
Orange Drop Cap on tone pot to middle tone lug  :icon_thumright:
Used Red on connections of the 3 way switch  :icon_thumright:

NO earth off the 3 way Strat style switch ..... As there is nowhere for it !!

So to me that is all correct .... But the lack of vol on the bridge SD JB is just killing me  :sad:

If you can spot anything wrong  :help:  PLEASE  yell out  :toothy10:

 

[Strat Avenger]

The JB should be way louder than the Jazz, so I suspect that you have either wired the JB in parallel instead of series, or you have one coil grounding out, (in which case it would hum just like a single-coil).

 

[TroubledTreble]

The wiring looks correct. The one thing I can't see is the bridge side of the switch. In this case it looks to be the side with the spring. Can you check to see that the common contact ( the contact with the bridge pickup hooked up to it) is actually making good contact. I have seen issues where during installation either due to a wire snagging and pulling it or to using too much heat, the little arm that pushes against the wiper will not make good contact.

Oh, I thought of one other possible issue. If the pickup has been subjected to high electromagnetic fields or near a powerful rare earth magnet, it may be partially demagnetized and this will cause low volume. You can get an idea if this is the case by using a screw driver or metal part and comparing the two pickups by touching the screw pole or slug poles. I would definitely check this.

 

[jimh]

Just to be clear...  Does the Vol pot work correctly when the neck pup is selected?

If yes, then the Pot is fine and it's a pickup/wiring problem.

 

[Updown]

Just to be clear...  Does the Vol pot work correctly when the neck pup is selected?

If yes, then the Pot is fine and it's a pickup/wiring problem.

Only goes from 10 Full ON ----- TO----- 9 Full OFF  (as stated earlier) No tapering off ...............
But its loud on the Jazz Neck pickup in both 1 & middle posy. On 10 but other is weak as !!

Thats whats weird is that if I killed the pot, why would the neck work & the other wouldn't .....  :icon_scratch:  Or dose that matter ?

The wiring looks correct. The one thing I can't see is the bridge side of the switch. In this case it looks to be the side with the spring. Can you check to see that the common contact ( the contact with the bridge pickup hooked up to it) is actually making good contact. I have seen issues where during installation either due to a wire snagging and pulling it or to using too much heat, the little arm that pushes against the wiper will not make good contact.

Added another pic & yep is connected ok :icon_thumright:

Oh, I thought of one other possible issue. If the pickup has been subjected to high electromagnetic fields or near a powerful rare earth magnet, it may be partially demagnetized and this will cause low volume. You can get an idea if this is the case by using a screw driver or metal part and comparing the two pickups by touching the screw pole or slug poles. I would definitely check this.

Everything was BRAND NEW .....

I noticed some foil on the pickguard coming into contact with the bridge spring .....  :icon_scratch:  If that dose anything .... I moved that anyway !!

After that I tried the screw driver test you mentioned earlier before seeing this & both sounded & metered
up fairly evenly in my RME Fireface Mixer.

I plugged in this one & held another guitar over the top to strum some strings (before doing a neck & strings for the millonth time)
Kind of sounded better than before ..... for some reason.... plus metered up sort of even-ish.

So tomorrow will try & set it up again & just hope something is right this time, If that fails, I'll just do a re-wire with a fresh pot & switch  :sad:

.... all I've done is move that foil !!!

Thanks all, for your help  :icon_thumright:  & will let ya know what happens.  :toothy11:

 

[Cagey]

I think your pot's shot. If it goes from full-on to full-off in the span of a few degrees of rotation, then the internal resistor strip has opened, almost certainly from too much heat. Pot bodies aren't meant to be soldered to, regardless of what you see or what the Monday morning quarterbacks will tell you.

Then, looking at the pictures, you can see where the solder has balled up, and is dull in appearance. Plus, the wire's insulation is melted. This means it was never hot enough to flow solder properly, but the parts you were trying to solder were acting like heat sinks and conducting heat to where you didn't want it to go. So, the solder's surface tension kept it in a ball, the low temperature made the solder crystallize, and the parts overheated to failure. I know this sounds contradictory to my first statement, but it's not. When your soldering iron isn't hot enough, you leave it on the part too long in an effort to get the solder to melt. The various parts and wire internal temperatures rise to whatever the iron's at, which will be much higher than the part can take, but not high enough to make a good solder joint. So, you end up with cold solder joints and wrecked parts.

Cold/crystallized solder joints often have a high resistance to them, or may even be open, so that may be why your bridge pickup sounds like it's turned down.

 

[jackthehack]

I had this issue before with  different models of SD pickup, don't know if it could apply to you because I can't see what I'd need clearly from your pictures; check the red and white wires VERY carefully along with the main wire bundle from where you cut it/pulled it back:

- It is possible to inadvertently make a small cut through the insulation where you cut away the black sleeve, been there/done that
- Somebody tried to update their pickups themselves with the same result; rather than trimming the wire back he tried to cram the excess under the pickup (bridge PU on an Epiphone LP) and install the the pickup jamming down the excess wire - this wound up kinking/partially breaking a wire that was then shorted to ground, I had to split the insulating cover almost all the way back up to the PU and repair it with electrical tape

Either instance wound up leaving the pickup in single coil mode with about 1/2 volume output.

 

[Updown]

Many Thanks to jackthehack & Cagey & other too that have helped ....  :doh:  NOTES TAKEN

I know about the earthing connectors for the pots, you can buy !! .... But haven't got any as yet ...... Will go that way from now on to save my Pots  :toothy11:

:sign13:  I have a heap load of 'position pointers' both in Nickel & Gold

Can I use these (with a drill hole to solder to)...... Just like the ones you buy ? 

Thanks again all  :icon_thumright:

 

[Cagey]

:sign13:  I have a heap load of 'position pointers' both in Nickel & Gold

Can I use these (with a drill hole to solder to)...... Just like the ones you buy ?   

Depends on what they're made out of. Not all metals will accept solder readily. If you've got a pile of 'em, do an experiment. Drill a hole to make sure you can, then try soldering a wire to it. If it works, great. If not, well, you know what you've gotta do.

You may need a different soldering iron, though. I'd recommend something in the 40 watt range, with a small chisel tip (sometimes called "screwdriver tips"). Avoid pointed/conical tips as they lose heat too fast.

1/8" screwdriver tip​

 

[Updown]

Just a up-date report on the simple wiring problem I had here, where the bridge pickup had no guts !!

1st .... I decided to get a new soldering iron (Temp controlled). 
2nd .... always use the grounding lugs.

So I re-did complete wiring of the Blue Strat with new pots & switch ...... BINGO ..... all perfect now, volume works correctly too  :toothy10:
I do believe 1st time round (as stated by others) that I cooked the Vol pot & had dry solder joints as well  :doh:

Will post this Blue Strat shortly (when custom dougie neck plate comes) ... in completed Warmoth builds.

Thanks Cagey  :icon_thumright: & all others as well  :icon_biggrin:
Couple of pic's of new wiring attached ..... Cheers  ccasion14:
The Moto of this story is ..... A good soldering iron & all ways use those ground lugs ..... just makes it so much easier  :cool01: