Good ways of attaching shielding

[FunkyKikuchiyo]

Perhaps a thread of such basic stuff should go in the tools and winding gear section, but it didn't seem to have a specific home.

For reasons that are not entirely relevant, I want to get some shielding onto some G10 material, but opted not to use the normal copper clad stuff, because I don't want the whole thing covered and it is less work to put some on where I want it than to remove the stuff I don't want.. I just want a little bit to help me arrange my grounds without short ugly pieces of wire. I'd like to attach it with more strength than the adhesive backed can provide... or typically provides. At this point I'm just going to opt to prep the surface best I can and let the adhesive do its thing, but I thought I should see if there is anything I'm missing.

Superglue of course doesn't work - it'll hold it well, but once you put a hot iron to it, it turns to smoke. Epoxy MIGHT work, but if the shielding is already adhesive backed, I'd probably have to get plain stuff, and besides that it seems like it would be really messy unless I can come up with a cleaner way of applying it.

I could of course find a completely different way of doing my grounding if it seems this is an ill-founded idea, but I figured I'd put it out here and see if anyone had some good advice.

Thanks!

[copperheadroads]

might be a little off topic but at one point i was considering making shielding paint
making conductive paint??

[David Schwab]

Get single side copper clad and etch the rest off like you were making a circuit board.

[marku52]

I've been working in the electronics field for 30 years, and have no easy answer for you, your problem is the same as that of any electronics designer who needs to prototype a new circuit. One good solution is the solid copper plane pcb you describe with the components "flying" in the air, attached to the ground plane wherever a component makes attachment to ground. Another is a custom pcb. Prices of these have plummeted in the last 10 years to where if you have more than one or two to make, it can make a lot of sense. These guys have a free pcb layout tool available, and costs of the boards are reasonable. The tool is pretty easy to learn too. Disclosure: I am a happy past customer.

ExpressPCB - Free PCB layout software - Low cost circuit boards - Top quality PCB manufacturing

Another way for simple boards used to be to etch it yourself. You'd layout the design using an etch resistant tape, then etch away the unwanted copper in a mystery fluid. You used to be able to buy the solutions and boards at Radio Shack, but I haven't seen it in quite a while.

[FunkyKikuchiyo]

I should probably be a bit more specific.

I'm making a blade style strat coil, and the bottom is such that there aren't obvious ways to ground it, but there is a giant piece of G10 there. Buying copper clad and etching everything else away is just too much work. That was my first attempt. I tried strategic etching, and it is still too much work, and it is hard to do it without screwing up the sound. I only want a small strip running down the middle to act as a little common island to solder the blade pieces and the drain for the lead wire. I'm afraid the weight of the lead wire would be too much for the adhesive back, but it might not be.

marku52, you may very well be right and there is no easy answer. I'm close to abandoning the idea and trying to find a neat way to use a wire. Maybe some solid core would be less offensive cosmetically... hmmm...

copperheadroads... shielding paint is lovely, but I want to be able to solder to it. Plus, there is some resistance in the paint.... whether it is enough to cause problems or not, I don't know.

[FunkyKikuchiyo]

I suppose I may be able to find some very thin copper clad board and glue small strips of THAT onto my piece... hmmm....

[copperheadroads]

I should probably be a bit more specific.

I was way off ...................lol
I rewound a couple of those cheap rail style strat pickups & both had copper clad for the bottom of the base plate & the magnet was completely wrapped with copper foil ,huh

[David Schwab]

The usual way that the blade Stat pickups work is that the blades and magnet poke through the bottom flatwork. So stick some adhesive foil tape over that and ground it. Then your blades are grounded. If you want total shielding, get some thin copper foil, not the adhesive kind, and use that. I get 40 gauge copper foil. You can glue that to your flatwork.

Here's a Tele blade pickup with a brass bottom

[big_teee]

The usual way that the blade Stat pickups work is that the blades and magnet poke through the bottom flatwork. So stick some adhesive foil tape over that and ground it. Then your blades are grounded. If you want total shielding, get some thin copper foil, not the adhesive kind, and use that. I get 40 gauge copper foil. You can glue that to your flatwork.

Here's a Tele blade pickup with a brass bottom

[ATTACH=CONFIG]14602[/ATTACH]

David can you elaborat a little more on that P/U in the Pic?
Is that a standard humbucker bar mag?
Also what bobbins do you use?
I've seen the baseplate for sale at Guitar USA.
I don't think USA has the right bars and bobbins tho?
Terry

[David Schwab]

David can you elaborat a little more on that P/U in the Pic?
Is that a standard humbucker bar mag?
Also what bobbins do you use?
I've seen the baseplate for sale at Guitar USA.
I don't think USA has the right bars and bobbins tho?
Terry

I bought that at GuitarPartsResource.com. It uses bobbins similar to the Strat rail bobbins at Mojo, but they are different. It's actually made from forbon. You could probably use the Tele rail bobbins from Mojo. The baseplate is the same one as at GuitarPartsUSA. I bought it figuring I'd rewind it, but it actually sounds pretty good. It's a little too hot in series, but I can switch it into Parallel when I want more of a Tele tone. In series it's still brighter than the small humbuckers like the Little '59, which is too dark and muddy for my tastes.

I have some Duncan rail Strat pickups here. I'll take a photo to show how they ground the blade.

[FunkyKikuchiyo]

Earlier versions were like what you had David, but I ditched it. The way the design is, I had to etch out so much copper that it got kind of ridiculous. Plus, I don't want the blades surrounded by copper. I just wanted enough to ground it and otherwise leave it unshielded (strange, but I have my reasons).

I have some heavy (12 gauge, I think) solid core lying around, I may give that a whirl since the adhesive backed may not work.

[big_teee]

I bought that at GuitarPartsResource.com. It uses bobbins similar to the Strat rail bobbins at Mojo, but they are different. It's actually made from forbon. You could probably use the Tele rail bobbins from Mojo. The baseplate is the same one as at GuitarPartsUSA. I bought it figuring I'd rewind it, but it actually sounds pretty good. It's a little too hot in series, but I can switch it into Parallel when I want more of a Tele tone. In series it's still brighter than the small humbuckers like the Little '59, which is too dark and muddy for my tastes.

I have some Duncan rail Strat pickups here. I'll take a photo to show how they ground the blade.

[ATTACH=CONFIG]14606[/ATTACH][ATTACH=CONFIG]14607[/ATTACH]

And the Magnet dimensions, do you remember the dimensions?
Probably not as wide as a regular bucker Mag?
T

[Joe Gwinn]

Earlier versions were like what you had David, but I ditched it. The way the design is, I had to etch out so much copper that it got kind of ridiculous. Plus, I don't want the blades surrounded by copper. I just wanted enough to ground it and otherwise leave it unshielded (strange, but I have my reasons).

There is no reason to remove all the copper foil, if one makes sufficient cuts to break up any eddy currents that would mirror the coil, and has the copper on the side away from the coil windings (to keep stray capacitance down).

[FunkyKikuchiyo]

There is no reason to remove all the copper foil, if one makes sufficient cuts to break up any eddy currents that would mirror the coil, and has the copper on the side away from the coil windings (to keep stray capacitance down).

I hear what you're saying Joe, but even at that I still ended up eliminating a lot. A lot of my trolling/irritating questions on this board were about trying to figure that stuff out. I'm using a laminated blade, so I wanted to remove all the shielding from around the blade (or at least on three sides), then I had a cut to take care of the eddy current looping, and then I have a series of eyelets and such, all of which needed to be carved away. I also trimmed it in other areas. By the time I did all of this I just decided that I was going to be just fine sacrificing the shielding. Plus, not using the copper clad opens up other possibilities for production, and it lets them be reversible for lefty sets. This design has become kinda complicated, and I want to make it simpler wherever I can so they can be produced for a reasonable price. I see the wisdom/convenience of using copper clad and carving it, but I tried it and really didn't think it was worth while. I'd reconsider it for other form factors, but for this one it just wasn't making sense. The only downside is I'm left figuring out how to do my grounding, but I'm confident I'll EVENTUALLY come up with something.

And just for my own curiosity, would the 1/16" gap COMPLETELY eliminate capacitances, at least perceptible ones? I feel like I already know the answer to it, but since we're on the topic I thought I'd ask.

[David Schwab]

I hear what you're saying Joe, but even at that I still ended up eliminating a lot. A lot of my trolling/irritating questions on this board were about trying to figure that stuff out. I'm using a laminated blade, so I wanted to remove all the shielding from around the blade (or at least on three sides), then I had a cut to take care of the eddy current looping, and then I have a series of eyelets and such, all of which needed to be carved away. I also trimmed it in other areas. By the time I did all of this I just decided that I was going to be just fine sacrificing the shielding. Plus, not using the copper clad opens up other possibilities for production, and it lets them be reversible for lefty sets. This design has become kinda complicated, and I want to make it simpler wherever I can so they can be produced for a reasonable price. I see the wisdom/convenience of using copper clad and carving it, but I tried it and really didn't think it was worth while. I'd reconsider it for other form factors, but for this one it just wasn't making sense. The only downside is I'm left figuring out how to do my grounding, but I'm confident I'll EVENTUALLY come up with something.

And just for my own curiosity, would the 1/16" gap COMPLETELY eliminate capacitances, at least perceptible ones? I feel like I already know the answer to it, but since we're on the topic I thought I'd ask.

Yeah, but why? Are the pickups coming out too dark? I ground the blades and have the entire pickup surrounded in copper foil in my bass pickups, and they are plenty bright. And very quiet.

I made this stacked Tele pickup from double sided copper clad board, and even grounded the copper and the blade, and it was ultra bright. I was shocked how vintage sounding it was, since that wasn't my intention.