Help w/ Mooncaster Wiring / Shielding

[beltjones]

Hey guys,

This is my first post, so any help for a new guy around here is greatly appreciated.

I'm working on my 2nd Warmoth guitar. The first was a Butterscotch Blonde Telecaster, and now I'm working on a Mooncaster with red dye and an amazing walnut neck with ebony fingerboard.

Here's my problem: I got it all wired up, and when plugged in it buzzes like crazy. I'm not talking about string buzz, I'm talking about a buzzing/humming sound coming through the amp that goes away when I touch the strings or the bridge. I'm aware that this buzzing is indicative of a shielding issue, and I verified that all of the solder connections and ground connections are good with a multimeter. I'm using a SD 59 in the neck and a Dimebucker in the bridge for now (probably soon to be replaced by a Pearly Gates that I have on the shelf).

So here's my question: How would you shield a mooncaster with an F hole in the electronics cavity? I can't apply shielding paint up in the "horn" where the switch sits, and likewise I can't get up there with tape. I also can't tape over the F hole, and I don't want anything to be visible through the hole, either.

I think Fender probably uses shielding paint in the cavity before laminating the cap to the body, but obviously Warmoth doesn't do that. I'm going to re-wire with shielded, grounded wire and see if that helps. I may also build some small "pot covers" for each of the pots and ground those, too. Does anyone have any other suggestions?

A note of caution for anyone thinking about building a Mooncaster - the area where the switch sits on mine wasn't relieved enough for anything but the shortest of switches. Even the Switchcraft "Short" switch wouldn't work. When I spoke to the folks at Warmoth they apologized and said these things happen with new designs. I'm still not sure what switch will work, but I'm thinking I may be able to use a blend pot to roll between the pickups.

Thanks in advance!

 

[mayfly]

Hmmmm.  I don't think it's a shielding issue.  I think it's a wiring issue.  I wonder if you've got the ground and hot leads reversed on the output jack.

Have any photos of the wiring?

 

[beltjones]

I don't think I have the leads reversed because if they were the noise would get louder when I touched the strings, not quieter. At least that's how I understand it.

I don't have pics of the wiring because I just pulled a lot of it out in order to replace it with shielded wire.

 

[Cagey]

The shielded cable should help a lot. It's amazing how much noise an unshielded wire to the output jack will pick up, especially for as long a run as you have from where the pickup switch is on that design. Even with humbuckers installed, it'll sound like you've put in hot single coils.

 

[beltjones]

The shielded cable should help a lot. It's amazing how much noise an unshielded wire to the output jack will pick up, especially for as long a run as you have from where the pickup switch is on that design. Even with humbuckers installed, it'll sound like you've put in hot single coils.

I hope so. I had to order another switch because while with the "right angle" switches it's relatively easy to get them in, to take them out destroys them.

In the mean time here's a picture. I really hope I get this thing figured out, because right now it's a beautiful guitar that has an amazing neck that just sounds like crap through an amp.

And again - a warning to anyone wanting to try a mooncaster - call Warmoth ahead of time and make sure they guarantee the switch you're going to use will fit. I think I'm over $100 in switches with this guitar so far trying to find one that will work, only to crush it getting it out of the guitar to change the wiring, and then ordering another. As much trouble as this thing has been I really wish I had gotten something else.

 

[Cagey]

How in the hell does that work? I'm looking at Mooncaster bodies in the Showcase, and there's no access cover for the switch cavity. So... it is hollow inside and you just cuss and thread the thing up there like you would on a ES style guitar, or what? And why are the switches getting destroyed by removing them?

Very fine guitar, btw. I like that a lot.

 

[beltjones]

Tremendous question.

To get the switch in you simply tie a string around the switch lever (after wiring it up, obviously) and pull it up through the hole. It's pretty easy to get the switch to "turn the corner" so it's upright and poking up through the hole with some needle nose pliers when it's on it's way in.

However, to get it out you have to also make it turn. But the thing is, how can you turn it on the way out? The base of the switch is basically square and resting against the mahogany of the body of the guitar, and you don't have any leverage points with the switch once it's through the hole. Furthermore, you can't use the maple top as a leverage point with a tool without ruining the finish, so the only way to get it out (that I have found) is to just crush the hell out of the switch and ruin it. I'll post before / after pictures of a switch here in a second.

I know that probably doesn't make sense, but it's the best explanation I can give at the moment.

When I called Warmoth they said the "short" switches would work, and on the phone I read the guy the reading from my micrometer that said - definitively - that they wouldn't. They then offered for me to ship them the guitar so they could install a switch and send it back. Pass. Sorry, but I want to be able to know what kind of solder connections and such are on my switch, not just trust that someone else did it right - that's kind of the point of Warmoth. There are other issues as well, like I had to relieve a bunch of mahogany from the back with a file in order to get the bridge volume pot into the guitar, but that's not such a big deal compared to the fact that this thing is relatively impossible to shield, and sounds like two single coils had a baby that hums and buzzes all the time.

 

[Cagey]

You probably know this, but the tip of the switch unscrews and comes off, making the thing slightly shorter. I don't know if that would help or not, but there's that.

As for the cavity shielding thing... contrary to popular belief, it's an exercise in futility. A lot of people do it because it makes sense on the surface, but it's pointless. If you have "noiseless" pickups of any type and use shielded cable, that's as good as it gets. If you use single coils of any type, nothing will help. All that copper foil and conductive paint is a waste of time and money. No matter how thorough you are, there are too many holes in the shield (pickups, jacks, pots, switches, seams, etc.) and like a submarine, it only takes one to ruin the whole thing.

The only place I've seen shielding work is on the back of plastic pickguards, and there it's not acting as a shield as much as a conductive plane. If it's not there, you'll generate up all sorts of static noise from rubbing the pickguard. You hear it on cheap guitars or homemade pickguards sometimes - you run you finger along the 'guard and get this light crackling noise in the amp? Sticking a patch of foil on there that contacts a ground somewhere keeps the static charges from building up.

 

[beltjones]

Yep, I've taken the knobs off the switches to get them in and out.

Obviously shielding any cavity with F-holes is going to be nearly impossible due to the F hole itself, which is why I'm considering little mini Faraday cages around each pot or at least each pair of pots. If the shielded wire doesn't help I'll try that, and if that doesn't work then this body is going in the fireplace. 

 

[beltjones]

Here is an approximation of what the switch looks like before it goes in.

Here is what it looks like after having to smash the switch to get it out. I have yet to be able to bend one back (this is the third one) to a point where it will function properly.

 

[Cagey]

I see. I also see where most of your noise is coming from. That wire HAS to be shielded. It should look something like this...

In this case, it was going into a Tele, so I wrapped the wires around backward to catch the ground lug on the switch...

... then wrapped the shields together. That might end up too tall for your body, but you get the idea. Then, you do the same sort of thing with the output jack. No wire that carries signal should go unshielded.

If that don't work, the fireplace it is. Just be sure to smash it up first, so you're not tempted to pull it out at the last minute and call it "reliced".

 

[beltjones]

You are the man! Thanks! I'm going to replicate that almost exactly, except I'll run a separate ground wire and I'll ground all the shields for the other wires somewhere else. Is that heat shrink tubing you have on the connections? And did you push the insulation and shielding mesh all the way up over the solder joint?

 

[Cagey]

Yes, that's heat shrink tubing. The braid is stripped back to expose the insulated inner conductor, then a piece of heat shrink (white) is applied to hold the braid back and prevent it from touching anything. Then, the inner conductor is stripped back a bit so it can be soldered to whatever terminal you want. Then the next piece of heat shrink goes on to cover the entire end including the terminal. That outer braid is going to be grounded at some point, so you don't want to let it touch anything that might carry signal.

 

[beltjones]

I love it. And I love you. Thank you! I'll post my results, and maybe a lucky person will be able to buy a semi-charred mooncaster body for cheap. heh.

 

[beltjones]

I think I may have found a pretty cool solution to the issue with the switch cavity being so short:

http://www.freewayswitch.com/information/about.html

Has anyone tried one of these? I'm going to wire it all up with shielded 4-conductor wiring, which *hopefully* will also help with the buzzing. I'll let you guys know how it works!

 

[beltjones]

Ok, so the freeway switch wouldn't fit either. I tried one more time with a right angle switch, and just getting it in bent the leads so that it shorted out somehow.

I called Warmoth and they offered some solutions, but as of yet I haven't decided what to do.

 

[Cagey]

Not to disparage your mad wiring skillz, but perhaps it's time to take the little rascal to a professional git-fiddler and see if their tender ministrations can be brought to bear on the problem. Sometimes you just have to back off a thing and let the other kids have a turn.

 

[Jumble Jumble]

I actually use normal 4 conductor humbucker wire for the run to the switch and back, I use red for neck pickup, green for bridge, white for return and black and bare for ground. There's one foil shield around the whole lot - works just great.