Rewiring Help! (Please!)

[Anthony_JB]

I think I've pulled out the harness in my Casino a good 20 times already and I have NOT been able to get my Casino's electronics to work successfully.

 

I went ahead a got a Gibson P90 in the bridge so I tried again. Only the stock Epiphone pickup works.

 

Today, I felt like giving it another go. I pulled it out, turns out the lead that goes from the pot to the switch had a bad solder joint. I went ahead and started over completely.

 

I tried something new that I saw on a wiring harness that was being sold on eBay.

 

No go! There is NO sound coming from BOTH pickups. I'm really frustrated but I don't want to take it to a tech. I want to be able to get this right. I just need you all's help.

 

SO: Here's what's going on. I've got no sound but some really crazy hum.

 

Here's a rough diagram of what it looks like.

 

 

I don't know if I have the jack or the switch wired correctly?

 

Also, that green wire is what I used to ground the pots. Not sure if that's done correctly.

[carverman]

I think I've pulled out the harness in my Casino a good 20 times already and I have NOT been able to get my Casino's electronics to work successfully.

 

I went ahead a got a Gibson P90 in the bridge so I tried again. Only the stock Epiphone pickup works.

 

Today' date=' I felt like giving it another go. I pulled it out, turns out the lead that goes from the pot to the switch had a bad solder joint. I went ahead and started over completely.

 

I tried something new that I saw on a wiring harness that was being sold on eBay.

 

No go! There is NO sound coming from BOTH pickups. I'm really frustrated but I don't want to take it to a tech. I want to be able to get this right. I just need you all's help.

 

SO: Here's what's going on. I've got no sound but some really crazy hum.

 

Here's a rough diagram of what it looks like.

 

[img']http://img6.imageshack.us/img6/4789/wiringxy.jpg[/img]

 

I don't know if I have the jack or the switch wired correctly?

 

Also, that green wire is what I used to ground the pots. Not sure if that's done correctly.

 

 

The wiring from the p_ups to the volume pots is incorrect. Go to the Seymour Duncan

web site and pull off a humbucker wiring diagram for Two humbuckers./two volumes/two tomes

and switch.

 

The P-90 is a SC, but as far as the diagram with only a hot and shield coming from each p_up,

it doesn't matter whether it's a p-90 or a humbucker for wiring purposes.

 

All pot cases should be tied to each other with a ground wire which should also go to the big

lug on the 3-way and the frame of the OUTPUT jack. The shields of the pickups should be

soldered to the volume pot cases.

[The_Buffalo]

While we're on the subject of wiring, maybe someone can help me. When I'm playing my Dot, Casino, ES 295 or my Rivieras (all with two pickups , two tone & two volume controls) with the switch in the middle position, turning down either volume control kills the guitar volume. What I'd like to do is select both pickups, and blend them by rolling off a bit of the neck or bridge pickup. All these guitars are completely stock, and have not been modified in any way. I notice I can do this on my Wildkat - turning down the neck or bridge volume will let me blend the tones.

[brianh]

While we're on the subject of wiring' date=' maybe someone can help me. When I'm playing my Dot, Casino, ES 295 or my Rivieras (all with two pickups , two tone & two volume controls) with the switch in the middle position, turning down either volume control kills the guitar volume. What I'd like to do is select both pickups, and blend them by rolling off a bit of the neck or bridge pickup. All these guitars are completely stock, and have not been modified in any way. I notice I can do this on my Wildkat - turning down the neck or bridge volume will let me blend the tones. [/quote']

I believe that problem can be rectified by employing "50s wiring" discussed here (Post #7): http://www.fenderforum.com/userphotos/index.html?recid=67609

 

and here: http://www.fenderforum.com/userphotos/index.html?recid=67609

[The_Buffalo]

...I believe that problem can be rectified by employing "50s wiring"...

 

 

Thanks - I'll give it a try. Why did Gibson abandon this wiring?

[Bender 4 Life]

Thanks - I'll give it a try. Why did Gibson abandon this wiring?

 

Being able to use either volume knob as a "Master Volume" comes in mighty handy sometimes............

I have no problem blending p'ups on my likewise wired guitars because the "Master" effect only takes place below a setting of 1 on either p'up.

Try increasing your guitar volumes for blending, and decreasing your amp volume.

For a "burnin' hot" Blues lead tone, I usually run the bridge p'up on 7 and the neck on 5 or 6 (depending on the guitar).

 

Sure beats re-wiring 8 of my guitars !!

[Anthony_JB]

I tried one more time today and I finally got both pickups working along with their respective tone and volume controls.

 

However, there's a lot of noise. When I touch the pickup covers the noise goes away. Whats the cause of this?

[Albannach]

I tried one more time today and I finally got both pickups working along with their respective tone and volume controls.

 

However' date=' there's a lot of noise. When I touch the pickup covers the noise goes away. Whats the cause of this?[/quote']

 

Check your grounding (earth) continuity, it seems as though you have a 'floating' earth and with you touching the metal parts you are completing the ground circuit. As said before all the braided screens should be grounded to the pots and a continuous connection between the PU casings, the pot casings, the bridge ground and the jack out is what you want.

 

There are quite a few threads and pics available in the forum if you use the search engine at the top of the page.

 

They call it 'a learning process' and we are all still learning! Keep at it and you will see the light at the end of the tunnel.

[brianh]

When I touch the pickup covers the noise goes away. Whats the cause of this?

All of the metal parts need to be part of the grounding circuit (except frets). The tail, strings and tuners are all metal to metal, so they need to be grounded at one point only. On a Casino I expect there's a ground wire jammed into the bridge post holes.

 

The pickup covers should already be grounded, but your description confirms that something is amiss so take a look and see if the PUP ground straps were not put back correctly, or are missing, broken, cold solder joint, etc. An Ohm meter is useful in tracing grounding shorts.

[Anthony_JB]

All of the metal parts need to be part of the grounding circuit (except frets). The tail' date=' strings and tuners are all metal to metal, so they need to be grounded at one point only. On a Casino I expect there's a ground wire jammed into the bridge post holes.

 

The pickup covers should already be grounded, but your description confirms that something is amiss so take a look and see if the PUP ground straps were not put back correctly, or are missing, broken, cold solder joint, etc. An Ohm meter is useful in tracing grounding shorts.[/quote']

 

There wasn't a ground wire when I pulled out the posts and the humming doesn't change when I touch the bridge or the tailpiece. It goes away ONLY when I touch the pickup covers, switch base, and jack.

 

ALSO: Pickup ground straps? What do those look like? Keep in mind that there's still a stock Epiphone P90 in there that doesn't use a braided lead. So the Gibson in the bridge is to ground.

[carverman]

There wasn't a ground wire when I pulled out the posts and the humming doesn't change when I touch the bridge or the tailpiece. It goes away ONLY when I touch the pickup covers' date=' switch base, and jack.

[/quote']

 

On hollowbodies, there HAS to be a groundwire from the tp to the output jack frame

which also is the shielded portion from the 3 way selector. You won't find a ground

wire on the bridge, as the traditional grounding method for hum is the tail piece,

whether a trapieze style or Bigsby or the stoptail.

 

If you haven't disturbed the original ground wire, then you are missing ground continuity

somewhere ....as the shields (not necessarily a braided shield..it can be just a loose bunch of

wires inside a foil wrapper inside the plastic cover), has to be soldered to the pot cases.

 

The pot cases need ground soldered to each other, and that ground also has

to extend to the 3 way ground lug AND the frame jack.

 

Having all those grounds in should minimize the hum..but these are SC p_ups after all.

and they will have some hum.

 

ALSO: Pickup ground straps? What do those look like? Keep in mind that there's still a stock Epiphone P90 in there that doesn't use a braided lead. So the Gibson in the bridge is to ground.

 

SC pups like the p-90 have a hot and a shield which is connected to the metal

case of the p_up inside. That shield wire can be a braided shield inside the

plastic wire cover or a bunch of loose small wires..

either way, these need to be soldered WELL to the volume pot case for

each respective pickup.

[brianh]

There wasn't a ground wire when I pulled out the posts and the humming doesn't change when I touch the bridge or the tailpiece. It goes away ONLY when I touch the pickup covers' date=' switch base, and jack.[/quote']

I haven't disassembled a Casino, but I have seen the ground wire go to the tailpiece on other hollowbodies. It has to/needs to be attached somewhere...

[The_Buffalo]

Being able to use either volume knob as a "Master Volume" comes in mighty handy sometimes............

I have no problem blending p'ups on my likewise wired guitars...

...for a "burnin' hot" Blues lead tone' date=' I usually run the bridge p'up on 7 and the neck on 5 or 6 (depending on the guitar).

 

Sure beats re-wiring 8 of my guitars !!

[/quote']

 

Thanks - I'll try that first.

[LongMan]

I haven't disassembled a Casino' date=' but I have seen the ground wire go to the tailpiece on other hollowbodies. It has to/needs to be attached somewhere...[/quote']

Right, and if the bridge is made of wood (like on the Broadway) the tailpiece is the only point you can connect. On some Les Paul and SG type guitars I found the ground wire soldered to the bottom of the lower tailpiece stud.

[Anthony_JB]

Carver, I'm not too sure what I'm missing maybe we can help isolate it.

 

This is what I have to ground.

 

Stock Epi P90 Black soldered on to volume pot.

 

Gibson P90 braided shield soldered on to volume pot.

 

All pots ground to each other - indicated by the green line on the diagram I drew up

 

Ground pots going to the ground on the jack and run to the ground on output jack.

 

What could I be missing. Because I was VERY sure to take a good look inside the Casino before I pulled anything out and DURING pulling out the harness and I did NOT see a ground wire leading to the tailpiece or the bridge.

 

Hell, I removed the TP a few months back to put in a Bigsby B7 and I had no noise.

[brianh]

Take some new pics and post.

 

We can get this fixed.

[deflepfan]

Stupid question as I don't know the ins and outs of the guitar in question, but is there a bridge ground on this one? Not mentioned so I thought I'd ask.

 

(And I know it wouldn't make a difference to his problem, but was curious.)

Sheila

[Anthony_JB]

I'm not too sure, Sheila. I really did not see a ground wire attached to the bridge or tailpiece.

 

Here are some shots of my refinished Casino. She is complete. It's not a perfect refinish job but I think it's damn good for a first attempt and the good thing about nitro is that it's very easy to strip. Acetone and a rag and it'll come off. After I do some more projects I think I want to give her another refin. But that's another story for another thread.

 

Enjoy.

 

 

I just got home from work so I'm pretty tired and don't want to pull the damn harness out. I'll take a shot of the harness tomorrow.

[carverman]

Carver' date=' I'm not too sure what I'm missing maybe we can help isolate it.

 

This is what I have to ground.

 

Stock Epi P90 Black soldered on to volume pot.

 

Gibson P90 braided shield soldered on to volume pot.

 

All pots run ground to each other - indicated by the green line on the diagram I drew up

 

Ground of pots going to the ground on the jack?? and run to the ground on output jack.

[/quote']

 

The hot wire from your volume pots that runs to the 3 way has to be grounded at

the volume pot as well, and you need to attach the shield to the large ground lug of

the three way as well AND ensure that there is shield continuity to the frame of the

output jack.

 

The way I do this is: (these are the wire runs from the volume pot to the 3 way switch)

 

1. run neck wire to 3 way, peel back shield away from the outside terminal at the terminal end

of the 3 way and tin the shield

2. run bridge wire to 3 way, peel back the shield away from the other outside terminal

at the terminal end and tin the shield

3. run the output of the switch (two inner terminals) peel back shield and connect all

shields together with some sort of solid wire which will act as your ground continuity

jumper

 

4. Insulate this solid wire and run under the 3 way to the large ground lug on the 3 way, and solder it.

This way the frame of the 3 way is grounded as well, and you have shield continuity all the way

to the output jack, which will continue down the guitar cord to the input of your amp.

 

Now, on the ES-335/DOT/Casino these runs are very short compared to a Les Paul,

but... because these are high impedance pickups, you need to ensure that the

shielding is as effective as possible all the way to the output jack!

 

P90s are SC prone to hum/buzz and not humbuckers,so you really need to observe good grounding.

 

 

 

What could I be missing? Because I was VERY sure to take a good look inside the Casino before I pulled anything out and DURING pulling out the harness and I did NOT see a ground wire leading to the tailpiece or the bridge.

 

Normally with archtops, Gibson/Epiphone have a black solid ground wire that comes out a tiny hole under the

end of the tp and this connects to either the frame of the output jack or a volume pot case.

 

With the Casino having a fixed t-o-m (instead of the usual movable wooden bridge t-o-m on full bodied archtops),

it is possible that the ground wire is connected from one of the bushings (the nearest one to the controls),

and run inside to either the output jack frame, or the volume pot case.

 

However, With the Casino, having a metal trapieze style tp, either way will work, but it is easier to add a small ground wire under the tp rather than have to pull out a bridge bushing to get a solid ground wire in there,

never mind trying to drill a hole for that wire to get from underneath the bushing over to the control pot.

There will be some wood reinforcement (like a bridge plate) for the t-o-m bushings on the Casino since

it doesn't have a tone block like the Dot or Sheraton.

 

The string ground wire should have been there, otherwise you will get a buzz/hum that goes away as soon as you touch the bridge or strings with your hand. So, In essence you are acting as a rf ground then.

 

Hell, I removed the TP a few months back to put in a Bigsby B7 and I had no noise.

But now you have disturbed the factory wiring and done some modding and if you missed a grounding

step, it is possible to get some noise..this is a very common problem with modding..besides cold solder joints

on pot cases.