Mosrite Mark I Ground Issue

[surfdude2000]

I just bought a Mark I USA Standard from Ed Roman and it's a thing of beauty, however I've been having a couple problems:

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This is the major one!

I noticed a popping sound, like a static crack, when I first got the guitar. When I tapped on the pick guard next to the switch you could hear it. This was not a hum or buzz. I removed the pick guard and thought I traced the problem to the ground leads that connect the pickups to the switch and re-soldered them. The popping would disappear when I touched the casing of the volume pot, which to me indicated a ground issue.

The popping no longer happens when I tap on the pick guard, but still happens, occasionally when I'm strumming. This is not an amp or cord issue, I've checked all that.

At first I thought it was the switch, but now I'm wondering if it could possibly be the capacitor or the ground that connects to the Vibramute or maybe a weak ground connection from the switch to the volume and tone pots.

Help!

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This is a string issue

I've been setting the Mark I up with heavy 12-54 D'Addarrio strings, which I've used for years on my other guitars. I've had two sets on where the high E string has failed at the ball end. The last one actually didn't break, but unwound at the ball! You got it right, it simply kept slipping and came unwound where it raps around the ball. I've never had this happen before and I've been playing for over 40 years.

Anyone ever run into this problem before?

Thanx

[Desert Surfer]

It look like you have got good advices from others, so I have changed my comments here.

Welcome to forum BTW.

[dubtrub]

I have experienced that on all my high out put pickup guitars, but it only occurs on one of my amps.

If you have checked all grounds, solder joints, changed chords and amplifiers, I don't know what else to tell you. It is not a capacitor issue though. Usually if there is a grounding issue you will experience loss of volume. But, if the bridge isn't grounded well, static electricity could possibly build up in your body and release through that point as an intermittent break in the ground. Also I would try a different outlet in your home. Sometimes a different outlet can change the ground loop effect.

As for the string unwinding at the ball. This is common and in a lot of currently manufactured and soldering the wrap is the only way to prevent this. I do this with every set of string just to avoid it happening at the wrong time.

[MWaldorf]

Congratulations on the new guitar. Mosrites aren't really designed for heavy strings. Lighter gauges will sit in the bridge saddles and string nut much better. It can seem odd at first; I've been playing Jaguars with 13s and Jazzmasters with 12s for years before switching to Mosrites with 10s (roundwounds no less!) Not necessary, but I think it's part of the "feel" for these guitars. It also will help with the vibrato spring tension and it might help with the string breakage as lighter strings will have less tension. I've only had the ball-end failure on my Mosrites a few times.

Mel


PS. Share a picture of the guitar when you get a chance!

[KRamone27]

Hey surfdude, I'm not sure if this is the case for yu but every guitar I have I modify it to have only a bridge pickup and 1 vol and 1 tone. Every time my pick hits the pickguard it produces a sorta popping sound. I have all my connections properly soldered and copper shielding tape in the cavities just so I had all my bases covered. I think what is happening is when the pick hits the pickguard above the cavity it's making it sound like you have a ground problem but it's not. Like I said that's my case. Kevin

[dubtrub]

surfdude2000,

Via your pm, it's sounds like you got the static problem figure out and resolved. Funny thing, one of my guitars just developed mucho static and an occasional pop this morning. I immediately thought of our discussion when that happened. Telepathy? I opened it up and checked all connections and solder joints, then tried some new contact cleaner/lubricant that I bought the other day at Radio Shack. I don't what that junk is but it cleaned the pots alright, no more static pop. But it left so much lubricant behind that it cut the volume in half and the tone control is very bass-y. If I can't get the crap out I'll have to replace the pots.

[surfdude2000]

First, thanks to everyone for their help and input. I've learned a lot in the process.

re >> E string unwinding at ball

I soldered the windings on the plain strings before changing the last set and everything tunes up and stays in tune like never before. Sweet!!!

A guitar tech told me this is "old school". Funny, I've been playing for 40 years and never heard of it before, but the result was like night and day. He also told me that D'Addarrio had recently opened up a new plant which might account for some production inconsistencies.

re >> switch issue

There was definitely a cold solder problem where the pickup ground leads join the switch, although you wouldn't know it by looking at them, because they looked perfect. Re-soldering those connections fixed the "pop" I would hear almost every time my pick would strike the pick guard right next to the pickup switch.

re >> static pop

It was pointed out that the intermittent "static type" pop that I would hear might be caused by static build up while I was playing and a weak ground connecting the bridge and Vibramute. This is new to me, but makes sense. The ground on the Mark I is not soldered to the Vibramute. So I soldered the ground lead to a piece of copper foil to give it a better contact and the "static pop" has disappeared. I can't say if it's totally gone, but I played for 20 minutes and didn't notice a thing.

Here's a pic...



Once again, thanks to everyone for their input.

Mosrite Rules!

joe

[MWaldorf]

Joe,
Glad to hear the fixes worked, and thanks for sharing the vibrato grounding technique.
Mel

[dubtrub]

But it left so much lubricant behind that it cut the volume in half and the tone control is very bass-y. If I can't get the crap out I'll have to replace the pots.

I got the pots cleaned out by flooding the pots with Naptha, Don't know what the ill effects (if any) will be from cleaning with Naptha but we'll soon find out,. Right now it's back together and seems to work perfectly. BTW, the cracking/popping noise on my guitar was a loose (cold solder) joint on the selector switch ground wire.

[surfdude2000]

Amazing! It's like deja vu all over again.

joe