Bitsa P Bass 1st problem sorted but now has new problem!!

[Jimothey]

My bitsa P Bass has suddenly started making a loud hum when you touch the strings, am I right I’m thinking that’s a Earth/Ground problem or is it a shielding issue?

At the moment the ground wire comes off the jack socket to underneath the bridge and is held in place when the bridge is screwed to the body

Would the fact the bridge is chrome plated make any difference to the quality of the ground??

Is there a better way or place I could ground the strings??

Thanks

Edited October 20, 2019 by Jimothey

[Cuzzie]

Grounding problem the hum normally goes away when you touch the strings/bridge as you complete the circuit.

Sounds like it could be a shielding thing - I hope someone confirms or denies!

has it got either carbon paint or copper tape in the cavities?

[Jimothey]

@Cuzzie I always thought it was the other way round if when you touch your strings the hum goes then you need to shield your cavities better and if it gets louder then it’s a grounding issue but I could be completely wrong 

The cavities are all sheilded with Alu tape (as I had a few rolls of it at work)and I tested it with my multi-meter in multiple places and it showed that it is conductive.............😀

Edited September 15, 2019 by Jimothey

[Cuzzie]

https://www.notreble.com/buzz/2015/04/15/solving-bass-hum-problems-grounding-vs-shielding/

 

yep you are right, I am a dullard - never type a reply whilst pretending to do bedtime, the wrong stuff comes out🤦🏾‍♂️

[Christine]

Does the same thing happen with any other instruments when plugged in? Could be a general domestic earth issue (or so I’ve read) 

[Jimothey]

4 hours ago, Christine said:

Does the same thing happen with any other instruments when plugged in? Could be a general domestic earth issue (or so I’ve read) 

No it’s just my P bass all the others are fine, I’ve just resprayed my Jazz White (to match my Precision) and I thought that the ground wire to the bridge might not be getting a good contact so I thought putting some Alu tape that I use for shielding between the body and the ground wire might help I’m going to try it on my Precision tomorrow night to see if it helps??..........🤞

Edited September 18, 2019 by Jimothey

[Cuzzie]

Or graphite paint the cavity and use a ring terminal is an option 

[Christine]

Check to see if any of the solder joints look dry and tin the end of the wire under the bridge in an eye around one of the anchor screws 

[Hellzero]

Are your cavities all connected to the ground ?

If not, it could solve the problem. That and check the conductivy between bridge and ground : the closest to 0 (zero) Ohm, the better.

 

[Jimothey]

2 hours ago, Christine said:

Check to see if any of the solder joints look dry and tin the end of the wire under the bridge in an eye around one of the anchor screws 

Yeah that’s a good idea I’ll give that a go, this is what I meant about the Alu tape under the bridge

1 hour ago, Hellzero said:

Are your cavities all connected to the ground ?

If not, it could solve the problem. That and check the conductivy between bridge and ground : the closest to 0 (zero) Ohm, the better.

 

No I’ve just made sure that the Alu tape comes over the edge of the cavity so the Alu tape on the pickguard is sitting on it 

Would you just put an extra ground wire off a pot or the jack and fix it to the cavity somewhere to ground the cavity??

10 hours ago, Cuzzie said:

Or graphite paint the cavity and use a ring terminal is an option 

I think I might get some graphite paint and rip-off the shielding and do it again properly.............😀

[Cuzzie]

Not a bad plan - Charles guitars has it in stock and comes pretty sharply, 30mls is about a fiver and 60mls about a tenner.

I think it’s a better way, I have had mixed results with copper tape in that if any of the wiring or pots are in contact the signal shorts out.

if you need a ring terminal they are cheap as chips and I am sure I have a spare I can Send you

[KiOgon]

37 minutes ago, Cuzzie said:

 

I think it’s a better way, I have had mixed results with copper tape in that if any of the wiring or pots are in contact the signal shorts out.

 

Same applies if any thing touches the shielding paint.

[Cuzzie]

Aye, could just be me, but have found less success it getting it right Cooper tape vs Paint, plus the black looks badass

[Hellzero]

1 hour ago, Jimothey said:

No I’ve just made sure that the Alu tape comes over the edge of the cavity so the Alu tape on the pickguard is sitting on it 

Would you just put an extra ground wire off a pot or the jack and fix it to the cavity somewhere to ground the cavity??

Make a star grounding, that's the best way to ground. Ans all cavities must be grounded otherwise it's a useless job. Aluminium is very good for grounding, but is impossible to solder (with tin) hence the use of copper.

[Twigman]

Is the bridge wire broken?

[itu]

On 19/09/2019 at 13:50, Hellzero said:

Aluminium is very good for grounding, but is impossible to solder (with tin) hence the use of copper.

Put oil to the soldering surfaces and you can solder Al. Check videos from youtube.

If there are issues with grounding, it can be easily covered with a tape or any non-conductive material like thin cardboard.

[Jimothey]

2 hours ago, itu said:

Put oil to the soldering surfaces and you can solder Al. Check videos from youtube.

If there are issues with grounding, it can be easily covered with a tape or any non-conductive material like thin cardboard.

Yeah I saw that on YouTube last night looks like it might be worth a try also I’ve seen it done where you sandwich the wire between 2 bits of Alu foil with a little bit of solder in it then heat it externally to melt the solder but it doesn’t melt the Alu foil 

i don’t really understand how will covering it up with non conductive tape etc stop the grounding noise issue??..........😳

[itu]

No, I meant that covering the conductive surface with a non-conductive material prevents issues with components touching the ground.

[Hellzero]

3 hours ago, itu said:

Put oil to the soldering surfaces and you can solder Al. Check videos from youtube.

If there are issues with grounding, it can be easily covered with a tape or any non-conductive material like thin cardboard.

Did you try this ?

Aluminium is very hard to solder. If you have lead in your tin, it might end up with a disaster.

You'll have to use flux and a zinc-tin solder to do it.

And you'll have to heat it over a long period too.

That's why it's preferable to use copper which will be soldered within seconds.

[Jimothey]

2 minutes ago, itu said:

No, I meant that covering the conductive surface with a non-conductive material prevents issues with components touching the ground.

Sorry I got my wires crossed (get it hee hee!!) 

I thought the problem was that I wasn’t getting a good ground hence why I’m getting the noise not that something was touching the ground that shouldn’t?

[Jimothey]

3 minutes ago, Hellzero said:

Did you try this ?

Aluminium is very hard to solder. If you have lead in your tin, it might end up with a disaster.

You'll have to use flux and a zinc-tin solder to do it.

And you'll have to heat it over a long period too.

That's why it's preferable to use copper which will be soldered within seconds.

Thank I haven’t but I’m thinking about ripping out the Alu and replacing it with copper instead to stop any other problems 

[itu]

1 minute ago, Hellzero said:

Aluminium is very hard to solder.

So is stainless steel. I have soldered both materials with success. I do have some professional experience because of my previous work.

I do prefer Cu to Al. Cu is easier - and better looking material.

[Jimothey]

20 minutes ago, itu said:

So is stainless steel. I have soldered both materials with success. I do have some professional experience because of my previous work.

I do prefer Cu to Al. Cu is easier - and better looking material.

I’ve braised Alu before (which I found very difficult!!) but never tried to solder it and because being in the building trade I’ve learnt how to do other trades over the years I can solder Copper with no problem 

I only used the Alu foil tape because I already had it but I’ve ordered a 4m x 30mm conductive adhesive Copper roll from eBay for £4 inc p&p to replace it and should have enough to do my Jazz and ‘72 style P bass aswell...........🤞

Edited September 22, 2019 by Jimothey

[Jimothey]

I sorted out the problem with the loud hum when you touched the strings by putting some Alu foil underneath the ground wire that went to the bridge but now my volume  and tone pots make a really loud hissing/humming sound apart from if they are on full or fully off!?!

I think I need to completely overhaul the electrics!!

[Samuel Burns]

I've had the same problem after installing a set of SPB-3's on my p-bass. After trying everything, I followed the advice of an internet guru that suggested to ground the pick up itself, through the pole pieces. It did the trick. I used coper tape making sure not to have any contact to the wires of the pick up, and then used a wire to connect it to the ground.