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. :D

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. :D

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.

Quote from adam on November 12, 2012, 14:01
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.

OK, Adam, I was thinking that if you needed to get a bit to get the kits out and had trouble finding a bit, I'm sure I could find one lying around the secret bunker that I could have Express-Posted across to get the kits moving.

The offer stands. Let me know if it's possibly needed as the current job is a Kramer fixer-upper and I won't need it for a little while.

Melbourne, huh... Quality service! :D

[ncass81]

So what you guys are saying is that It would be advisable to pull apart my Lp and insert a earth wire from the bridge to the bridge tone pot.

[adam]

Quote from ncass81 on November 12, 2012, 15:26
So what you guys are saying is that It would be advisable to pull apart my Lp and insert a earth wire from the bridge to the bridge tone pot.

Hi Nick, I was hoping you would catch this thread. I think from a safety aspect, I would recommend running another earth wire from the bridge tone pot to the closest bridge post. This just requires drilling a hole from the control cavity to that bridge post hole. To do this you will need an extra long bit. Dmac suggests a 3 mil bit, but I would go a bit thicker. These are pretty inexpensive. Then just leave the bare wire so it's contacting with the bridge post when you put the bridge post back in.

I'm going to do up a video instruction for this, so if you want to wait for that I should have it online in a few days.

Sorry for the inconvenience. Fortunately we got this before we sold too many of these kits, so only a few people will need to be contacted.

[ncass81]

That wont be a problem, I might get some copper adhesive at the same time and do it all at once. I dont know why I didn't think of this myself.

[dingobass]

Yep, I earthed my LP by drilling a hole from the post hole into the cavity.
I was surprised that this was not pre drilled, but it was no problem for me to do it.

Problem solved!

[adam]

Quote from dingobass on November 12, 2012, 17:22
Yep, I earthed my LP by drilling a hole from the post hole into the cavity.
I was surprised that this was not pre drilled, but it was no problem for me to do it.

Problem solved!

Good to hear DB, one less person I need to contact and explain our stuff up. I do wonder how many customers actually follow the video instructions. I take it you didn't need to refer to them DB?

For the record, what sort of bit did you use dingobass? Any problem making the distance from the control cavity to the bridge post? Also, did you actually solder the earth to the bridge post or just have it at resting contact?

[adam]

Quote from dmac on November 12, 2012, 14:30

Quote from adam on November 12, 2012, 14:01
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.

OK, Adam, I was thinking that if you needed to get a bit to get the kits out and had trouble finding a bit, I'm sure I could find one lying around the secret bunker that I could have Express-Posted across to get the kits moving.

The offer stands. Let me know if it's possibly needed as the current job is a Kramer fixer-upper and I won't need it for a little while.

Melbourne, huh... Quality service! :D

Hey dmac, I responded to this earlier from my phone but it doesn't seem to have registered. Thanks for the offer, but I'll go and buy the appropriate bit so we can fix the remaining stock and any that arrive with a grounding hole drilled.

I'll also contact the factory and ask them to pre-drill the necessary hole.

[dingobass]

Quote from adam on November 12, 2012, 17:36

Quote from dingobass on November 12, 2012, 17:22
Yep, I earthed my LP by drilling a hole from the post hole into the cavity.
I was surprised that this was not pre drilled, but it was no problem for me to do it.

Problem solved!

Good to hear DB, one less person I need to contact and explain our stuff up. I do wonder how many customers actually follow the video instructions. I take it you didn't need to refer to them DB?

For the record, what sort of bit did you use dingobass? Any problem making the distance from the control cavity to the bridge post? Also, did you actually solder the earth to the bridge post or just have it at resting contact?




Hi Adam,

I did watch the vids, but it was some weeks before I built the LP.

I actually thought at the time that it was part of the build that was left up to the individual builder, which I did think at the time was a bit different but there you go...

Having built Basses I automatically earthed the bridge without too much thought.

I dug out my extra long 4 mm drill bit and bored that hole :D

I just relied on the contact of post on wire and as the fit is tight, it worked OK.
Checked it with the multi meter just to make sure.

Quote from dingobass on November 12, 2012, 18:05
I just relied on the contact of post on wire and as the fit is tight, it worked OK.
Checked it with the multi meter just to make sure.

And that's all that needs doing. I normally strip 1-1,5cm of insulation off ad give it a light twirl. If I feel particularly energetic I might tin the wire with a bit of solder, but not solder it to the post.

I position the wire so that its entry point into mounting hole is roughly where the insulation ends.

[adam]

A Facebook question from our friend Nadiene in Ocean Grove (remember the cool, swirly LP-1?)

"Nadiene Dini: Any hints if the bridge posts have already been hammered in????"

I've actually pulled out my bridge posts, using the back of a claw hammer (and cardboard to protect the body), but it's not something I'd recommend, especially given Nadiene's kit's excellent finish.

Any other suggestions for earthing the LP-1 which has been fully assembled?

[dingobass]

Quote from adam on December 5, 2012, 17:21
A Facebook question from our friend Nadiene in Ocean Grove (remember the cool, swirly LP-1?)

"Nadiene Dini: Any hints if the bridge posts have already been hammered in????"

I've actually pulled out my bridge posts, using the back of a claw hammer (and cardboard to protect the body), but it's not something I'd recommend, especially given Nadiene's kit's excellent finish.

Any other suggestions for earthing the LP-1 which has been fully assembled?






Hmmm. Good question...

The first work around that springs to mind is this.

Get a length of brass rod, say 4 millimetres diameter.
With a long shanked 4mm drill bit, carefullly drill back from the control rout out to the post.
Place a bead of solder on the end of the brass rod and gently tap it into the hole untill it hits the post.
Solder a wire to the end of rod and then to tone pot.

If I come up with a better idea I will let you know.

Maybe dMac will have a better solution?

Quote from dingobass on December 5, 2012, 23:37

Quote from adam on December 5, 2012, 17:21
A Facebook question from our friend Nadiene in Ocean Grove (remember the cool, swirly LP-1?)

"Nadiene Dini: Any hints if the bridge posts have already been hammered in????"

I've actually pulled out my bridge posts, using the back of a claw hammer (and cardboard to protect the body), but it's not something I'd recommend, especially given Nadiene's kit's excellent finish.

Any other suggestions for earthing the LP-1 which has been fully assembled?






Hmmm. Good question...

The first work around that springs to mind is this.

Get a length of brass rod, say 4 millimetres diameter.
With a long shanked 4mm drill bit, carefullly drill back from the control rout out to the post.
Place a bead of solder on the end of the brass rod and gently tap it into the hole untill it hits the post.
Solder a wire to the end of rod and then to tone pot.

If I come up with a better idea I will let you know.

Maybe dMac will have a better solution?



Remember you have 3 bushings to choose from that are close to the control cavity or are close to wiring routs.

I prefer to screw a bolt into the bushing (with matching thread).

Put the guitar on a protective surface. Put some rag around the bolt. With a tool that lets you get a grip on the bolt, pull the bolt up at 180 degrees (to the bolt.)

You will find that if you are pulling straight up and not deforming the wood by pulling at an angle, it will come out surprisingly easily. You cannot use a lever action because you expend a lot of energy deforming the wood.

Works for me every time.

Drill hole, thread tinned wire to control cavity, replace all done.

Now to offload the damn truck...