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My continued adventures in pickup building

If you haven't read the last instalment:

http://www.cigarboxnation.com/profiles/blogs/my-first-2-weeks-of-pickup-building

...so, the problem I was left with was that I hadn't grounded the strings and both my tailpiece and bridge are made of wood (and bone, neither great conductors!)

I decided to go for a pretty drastic solution. Here is the problem:

9353808473?profile=originalI took the strings off and took a saw to to the tailpiece... Here is my solution:

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This is part of a hanging fixture ( one of the advantages of working in a department store, few though they are), I used a Dremel to cut it to the right size and drilled a few holes to mount it to the back of the guitar and 3 to hold the string ferrules. I have used bike spoke nipples for these. At 20p each at my local bike shop they're a lot cheaper than real string ferrules!

The idea was to solder a wire to the inside of the tailpiece and connect it to the ground on the back of the volume pot. What I hadn't considered is that it's bloody difficult to solder to stainless steel. I didn't have any flux to hand so I cheekily superglued a strip of copper foil tape to the tailpiece and soldered the wire to that... hopefully this will work!

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So here's the new tailpiece. I actually never liked the original so wasn't too sad to see it go. The sound still seems to be just as nice so I'll take that as a success...

I soldered the wire onto the back of the pot and checked all the connections. I plugged it in and the loud continuous buzzing had all but gone! I now had a slight buzzing which went away when I touched the strings... after sending myself mad Googling this for a couple of hours I found a lot of conflicting advice, mainly:

  1. The guitar is not grounded properly
  2. The guitar is grounded properly, and it is your body causing the interference. The hum goes away when you touch the strings because you complete the ground loop
  3. The guitar is wired correctly, but the soldering job is bad

Now I'm perfectly ready to accept that I'm not very good at soldering, as I have no previous experience with it. However I figure that if everything works, the soldering should be fine, right?

I eventually decided to believe number 2. I noticed that there was very little hum when I left the guitar in the middle of the room, and stood away from it. I also noticed that not having my amp plugged into a socket with a PC, Laptop and a baby monitor made a big difference. If anyone reading this has any other ideas I'd love to hear them!

So, I still had one last trick up my sleeve - my copper foil tape. I thought I'd give it a try on one of the new pickups I made following (I thought) Bob Harrison's suggestion.

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So I have potted the coil, wrapped it in a few layers of plumbers' tape, and then wrapped in a layer of copper foil. I then ran a jumper lead from the ground connection (start of the coil) and connected it to the foil. I also used a little lump of solder to seal the foil shut in case the glue deteriorates over time.

Somewhat foolishly, I whacked the pickup in the guitar without checking it first... when I plugged it in, it didn't work. No signal, some buzz, but definitely no sound coming from the strings. Without really bothering to figure out why, I took it out and removed the copper foil (trying to grasp electronics by this point was making my head hurt). After ruminating on this over the last couple of days, I think that maybe I shouldn't have connected the ground wire to the foil and the start of the coil. If the ground is the path of least resistance, maybe I have just forced the current directly to ground... again, any feedback on this would be appreciated!

Sure enough, after removing the foil and the jumper lead, the pickup worked again. I strung it up, closed the access panels and called it a day. Some noise, perhaps, but hardly too offputting for a first attempt!

9353811878?profile=originalSo there it is! Reasonably happy with it - will post some vids soon. Next step is to start messing around with tone pots and capacitors!

...and here's a video - let me know what you think!

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