Earthing a two humbucker kit

[adam]

We received this question from Rosemary Schubert:

I have noticed in you instruction videos that you don't earth a wire to the bridge of guitar,
is there any reason why you don't, or you have to?
Every LP and SG I have wired I run earth wire to the bridge to earth strings, like on a strat.

I responded:

"I did consider whether I should address the earth wire in the LP/MB/SG/EX wiring videos, but it would require extra drilling and, to be honest, I didn’t think it was necessary.

It’s totally up to you. When you’ve wired up the kit, give it a test and see how much hum there is. On my LP-1, I didn’t have any noticeable hum at all and it’s not earthed to the bridge.

If you are getting some hum and want to run an earth wire, you will need to drill from the control panel to the bridge post hole. To do this, you’ll need to buy an extra-long drill bit (and be very careful).

If you do have problems with hum, put up a post on our Forum, we’ve got a bunch of really helpful members who really know their stuff and they’d be happy to give you advice."

____
I thought I would post this to the forum in case others had comments and also so this issue would be searchable for others who are also wondering about earthing their LP/SG/MB/EX or other 2 x humbucker kit.

[dingobass]

Quote from adam on November 11, 2012, 19:29


If you are getting some hum and want to run an earth wire, you will need to drill from the control panel to the bridge post hole. To do this, you’ll need to buy an extra-long drill bit (and be very careful).

If you do have problems with hum, put up a post on our Forum, we’ve got a bunch of really helpful members who really know their stuff and they’d be happy to give you advice."

If you do get any noise, shielding the control rout out and pickup routs should fix the problem, also using shielded wire, or wrapping the wires with copper tape will help.

If you do shield your wires( generally I shield the long runs to out put jack) remember to solder the copper to your cavity shielding..... Dmac has posted a really good article on shielding, well worth reading!

[Gavin1393]

The bridges of electric guitars and basses need to be grounded for a couple of really good reasons:

The instrument may hum even with humbuckers, and this humming will change or go away when the player touches the strings or bridge.
The possibility of a serious electrical shock exists if the bridge ground is faulty and the player touches a microphone or piece of gear attached to a different signal chain.

Otherwise echo Dingobass's recommendation to check out Dmac's excellent piece on shielding.

[adam]

Quote from Gavin1393 on November 11, 2012, 20:46
The bridges of electric guitars and basses need to be grounded for a couple of really good reasons:

The instrument may hum even with humbuckers, and this humming will change or go away when the player touches the strings or bridge.
The possibility of a serious electrical shock exists if the bridge ground is faulty and the player touches a microphone or piece of gear attached to a different signal chain.

Otherwise echo Dingobass's recommendation to check out Dmac's excellent piece on shielding.

If that's the case, then I need to give customers some video instruction on earthing to the bridge. I'm not a Gibson player, so I'm not familiar with their earthing process. I imagine you would run a ground wire from the bridge tone pot to the bridge. However, there is no pre-drilled hole for doing this.

So, I guess you would need to drill from the control panel to the closest bridge post.

Any other ideas?

Quote from Gavin1393 on November 11, 2012, 20:46
The bridges of electric guitars and basses need to be grounded

+1

You can solder a wire to the spring retaining plate if it's a trem-style guitar, or if it's for example an LP-style you can have stripped wire down the mounting hole and feed that through to the control cavity. In either case you will need a hole drilled, but it is small.

[adam]

If we agree that a hole from the control panel to the bridge post is the best option, I can get the factory to have this hole ore-drilled. I'm just wondering if there's another "no drill" option.

Quote from adam on November 12, 2012, 08:21
If we agree that a hole from the control panel to the bridge post is the best option, I can get the factory to have this hole ore-drilled. I'm just wondering if there's another "no drill" option.

1. There is no such thing as too much grounding.

2. Surely your supplier is making kits for other companies. I can't believe that the (since it's a 'bucker, SG or LP) kits will be leaving the factory without a drilled grounding wire hole from a bridge or tailpiece mounting hole.

Back to the issue- I think I'm reinforcing Gavin's comments- the builder is trying to earth the bridge, strings and tuning machines to get rid of any interference they pick up. If you don't earth them somehow, there is only one place for that electrical interference to go, and it's the closest metal to them. And that is 90% going to be the pole pieces in the pickup, or 10% the player.

Not good. A badly wired humbucker is a complete humbucker in name only.

I've never wired a guitar without earthing the bridge (no matter what kind), strings and tuners. If the user is using star grounding (all the earths connecting at one point), then that's where it should be soldered.

The hole required need only be 3mm wide, because you only need ~22swg wire (a bit under 1 mm). On a ST or SV, go from the spring cavity to the control cavity. On an LP or SG, from the closest of the tailpiece or bridge mounting holes to the control cavity (of course, if the channel for the wiring is closest, take it into there.) On a TL, from under the bridge into the control cavity.

You can do it, Adam. You may need patience, forethought, a longer bit than usual and a variable speed drill on low so it doesn't side around. If a 6mm drill bit will get you to the cavity, use it instead of trying to finesse a 3mm when it won't be seen by anyone.

And, of course, lots and lots of nice blue tape to protect the woodwork.

Let me know if you have any trouble. When are the kits due into the Pit Bull kennel?

[Gavin1393]

Quote from adam on November 12, 2012, 08:21


I can't believe that the (since it's a 'bucker, SG or LP) kits will be leaving the factory without a drilled grounding wire hole from a bridge or tailpiece mounting hole.

It was something I noticed when I looked at a number of suppliers of kits on offer before discovering Pitbull. What I discovered was that often the very cheap bodies have not had all the channels for wiring and PUP's routed into the body. It seems that you either have to be very vigilant in checking this aspect before buying the body or simply accept that the item was sold at a discounted price because the supplier expected the builder to do this work for themself.

[adam]

Quote from dmac on November 12, 2012, 13:39

Quote from adam on November 12, 2012, 08:21
If we agree that a hole from the control panel to the bridge post is the best option, I can get the factory to have this hole ore-drilled. I'm just wondering if there's another "no drill" option.

1. There is no such thing as too much grounding.

2. Surely your supplier is making kits for other companies. I can't believe that the (since it's a 'bucker, SG or LP) kits will be leaving the factory without a drilled grounding wire hole from a bridge or tailpiece mounting hole.

Back to the issue- I think I'm reinforcing Gavin's comments- the builder is trying to earth the bridge, strings and tuning machines to get rid of any interference they pick up. If you don't earth them somehow, there is only one place for that electrical interference to go, and it's the closest metal to them. And that is 90% going to be the pole pieces in the pickup, or 10% the player.

Not good. A badly wired humbucker is a complete humbucker in name only.

I've never wired a guitar without earthing the bridge (no matter what kind), strings and tuners. If the user is using star grounding (all the earths connecting at one point), then that's where it should be soldered.

The hole required need only be 3mm wide, because you only need ~22swg wire (a bit under 1 mm). On a ST or SV, go from the spring cavity to the control cavity. On an LP or SG, from the closest of the tailpiece or bridge mounting holes to the control cavity (of course, if the channel for the wiring is closest, take it into there.) On a TL, from under the bridge into the control cavity.

You can do it, Adam. You may need patience, forethought, a longer bit than usual and a variable speed drill on low so it doesn't side around. If a 6mm drill bit will get you to the cavity, use it instead of trying to finesse a 3mm when it won't be seen by anyone.

And, of course, lots and lots of nice blue tape to protect the woodwork.

Let me know if you have any trouble. When are the kits due into the Pit Bull kennel?

Just to be clear, it's only the 2 humbucker kits which don't have an earth wire hole pre-drilled. The ST, TL and SV all have them and our instructional videos cover grounding the guitar on these models.

I'll contact the factory and ask them why they don't pre-drill these holes and share their response. No problem for myself to drill an extra hole, but it would make if easier for the novices if these were already drilled.

Dmac the guitar kits went to Melbourne by mistake. We now expect to have them around 29 November. It was a mistake at the Port.

[Gavin1393]

Melbourne?? They will be well travelled by the time they get back!

Bugger about the dates! I am moving on 29th and 30th and will not expect to have much time to look at the new arrivals. Will give everyone else a chance to look.