Allparts copper shielding

T-Mac · #1 03-07-2010, 09:38 PM

Hey folks,

I plan on swapping out PUPs in the near future. Since I'll have the bass opened up at that point, I figured it would be a good time to shield the PUP and control cavities.

Does anyone know if Allparts copper shielding material is conductive on the adhesive side? If not, I guess I'll have to do the "fold over" where 2 pieces join up?

Thanks!

**line6man** · #2 03-07-2010, 10:04 PM

AFAIK, only the Stew Mac copper tape has conductive adhesive.

You definitely have to solder the pieces together!

The first thing that comes to mind is that I doubt it if simply having the pieces touch each other by folding over would provide sufficient contact.
The second thing that comes to mind is that you will lose contact when the copper starts to form it's patina over time.

jwymore · #3 03-07-2010, 10:14 PM

It's actually really easy to solder the Allparts shielding, probably less time and effort than the folding would be and a sure thing for getting continuity across all the pieces.

Bassamatic · #4 03-07-2010, 10:39 PM

Is there some reason you can't get the StewMac copper? As you end up with lots of little pieces to fit everything properly, it is a pain to do the soldering by comparison. Just get the one large roll (2") and then you can cut it into any needed size.

Be sure that the pup cavity copper is connected to the main ground (You may need to use a wire), and that there is a way to be sure that the copper under the pickguard is also grounded. I let a tab of the copper come up over the edge and under one of the pickguard mounting screws to make the connection.

It is also a good idea to give a few twists to the pup wires. This makes "twisted pair". It is not as good as a shielded wire, but does help to reduce hum pickup further.

Willicious · #5 03-08-2010, 03:03 AM

I recently used Acheson Electrodag shielding paint on my newest Jazz build.
If it works out, I'm never going back to shielding tape.
We'll see.

**line6man** · #6 03-08-2010, 07:22 AM

Quote:

Originally Posted by Willicious

I recently used Acheson Electrodag shielding paint on my newest Jazz build.
If it works out, I'm never going back to shielding tape.
We'll see.

Copper tape generally works better than shielding paint, because it's less resistive.

Personally, I wouldn't bother with shielding paint for that reason.

How much resistance did you end up with with the paint?

Medford Bassman · #7 03-08-2010, 07:26 AM

I used the Stew Mac shielding tape on an SX P bass I bought in Sept. WOW. It worked fantastic. Seriously, it went from noisy as hell when I let go of the strings to scary dead silence.

I've tried the paint as well. Definitely not as good as the tape.

T-Mac · #8 03-08-2010, 07:49 AM

Thanks for the info, all! I didn't realize how much I didn't know.

Something I've always wondered about...is it worth wrapping the PUP leads in copper foil (as shown in the following, half way down the page)?

http://www.stewmac.com/tradesecrets/...0052_shielding

Thanks again!

**line6man** · #9 03-08-2010, 08:18 AM

Quote:

Originally Posted by T-Mac

Thanks for the info, all! I didn't realize how much I didn't know.

Something I've always wondered about...is it worth wrapping the PUP leads in copper foil (as shown in the following, half way down the page)?

http://www.stewmac.com/tradesecrets/...0052_shielding

Thanks again!

I wouldn't shield the pickup like they show.
That would affect the tone.

John Bigboote · #10 03-08-2010, 08:35 AM

Coupla things:

- Stew-Mac claims the adhesive on the reverse of their copper tape is conductive, so you don't need to solder it. I solder the joints anyway, but that's what they say.

- The way they show for shielding pickups is a major PITA, but I believe it's the only way to truly shield pickups. Just shielding the cavity might help some, but it doesn't finish the job because you're not creating a conductive "box" within which all the electronics reside, unless you somehow complete the job, like by shielding the inside of the pickup cover and connecting them with a wire. And that seems like a MAJOR PITA, if it's doable at all.

-While it seems logical that wrapping copper tape around a copper coil might seem like it would change the pickup's tone, I'm not convinced that's true. Would like to hear an EE chime in on that point. I've done it their way, and I don't *think* it changed the tone, but it's pretty darn hard to A/B pickup tone when a day elapses during the surgery (I didn't record it before/after)... FWIW, I ended up removing that shielding a while later, and not only didn't notice a change in tone, but also didn't notice any increase in noise, so I concluded the whole thing was a fool's errand.

-jb

bassbenj · #11 03-08-2010, 07:31 PM

Quote:

Originally Posted by line6man

Copper tape generally works better than shielding paint, because it's less resistive.

Personally, I wouldn't bother with shielding paint for that reason.

How much resistance did you end up with with the paint?

I've seen paint that worked well and paint that didn't work so hot. I have no idea why it's variable like that. Copper always works which is why I use it even though it's more work.

Craig_S · #12 03-08-2010, 07:37 PM

I won't use anything but the Stew Mac stuff. It's the easiest way to do things. You just overlap the tape and you're good to go.