can you use aluminum tape to shield

[bajaasdad]

guitar cavities?

I'm not much of a metallurgist, nor an electrical person. Will it work?

[HOBBSTER01]

yes

[Hodgecraft]

I believe the reason why copper is usually using instead of aluminium is because aluminium doesn't take the solder nearly as much (if at all) so you cant get strong electrical connections between each piece of tape. I'm sure someone more knowledgeable than me will come and clarify though.

[DeepSouth]

Originally Posted by bajaasdad

guitar cavities?

I'm not much of a metallurgist, nor an electrical person. Will it work?

Yes - some people use aluminium tape instead of copper. I use copper tape that has conductive adhesive - that way I don't have to solder all the bits of tape together. I've seen some people just use aluminium foil.

My guitar tech reckons that it makes virtually no difference whether you shield your cavities or not. Having said that - I've done it on the guitars that I've built myself and I was careful to overlap the tape so the shielding on the pick guard contacts with the tape in the cavities properly. You also need to make sure all your ground wires attach to one point eg. one potentiometer to eliminate any ground loops.

I'm happy with the guitars I've shielded but I admit the guitars I own that aren't shielded aren't exactly horrendously annoying in terms of hum either. I sometimes wonder whether the whole shielding thing is a bit of myth... meh...

[David Collins]

Yes, aluminum tape works fine. As others mentioned, copper tape with conductive adhesive may be preferred to easily achieve reliable continuity between strips, but if you tuck and fold under tabs every few inches on aluminum tape, or join them with small brads or staples, you can get good and reliably continuity between strips as well.

I did some quick tests between materials a while ago - aluminum tape, aluminum foil, .002" copper stock, and nickel shielding paint of various thicknesses.

A coil mounted in a test box with a track (with a contact strip) in front to slide different shielded boards through.



Several test boards of different shielding materials -



And then put a noise source (fluorescent desk lamp for most of the tests) in front of the coil and slid the various plates in and out.



I did not get near so far as reliably measuring db reduction or anything, but sliding any of the plates between one material and the other in real time revealed no differences at all in noise reduction to the ears, or to a spectrum analyzer.

For me the choice comes down to cost, ease of application, and durability/reliability. If installed right though, any will work.

[bajaasdad]

[Jack Wells]

because aluminium doesn't take the solder nearly as much (if at all)

Lets make that not at all.

If using aluminum, you'll need to make the electrical connections with wire and screws.

[dman]

I've used aluminum duct tape with good results. The adhesive is not conductive, so where you overlap, you have to bridge it for continuity. I just took a small strip of the tape turned upside-down with a larger piece on top (rightside-up) to adhere it across the seam.

That said, the best stuff, IMHO, is electrodag, a copper-silver paint used by the electronics industry. Very easy to apply..two coats with a flux brush. It's far better than the black graphite-based shielding paint that Squier put in the cavities of my Pro Tone Strat...it's now virtually silent, unless I'm 4 inches from the output transformer...that doesn't happen much!

There's a seller on Ebay who sells electrodag in 1 oz. jars... enough to do 2-3 guitars...for about $12. I don't remember his seller name, but if you search "electrodag', you'll find it.

[DavidP]

I find copper easier to work with as I can by a 1ft square piece from a stained glass supply store and cut to fit the cavity. The stuff I use is conductive but I still tack solder the joins as preventive maintenance. WRT to aluminum, my experience is that it doesn't take solder and the overlaps don't provide continuity.

I prefer foil over that black carbon paint, which never seems to cure fully so you always get a smudge when you touch it, and you still get residual resistance (even after 3 coats) compared to foil.. I'd love to try that electrodag paint but its really shot up in price! (see http://www.ebay.com/itm/Guitar-Condu...item4cfa5cf294)

[Jupiter]

In Japan you can find copper-based shielding paint. It's called "Noise Hell"! :-)

[jefrs]

Originally Posted by Jack Wells

Lets make that not at all.

If using aluminum, you'll need to make the electrical connections with wire and screws.

It is fairly easy to solder aluminium. You have to abrade its surface under a layer of grease or oil, and solder through the grease. Aluminium oxidises its surface immediately in air and this will not solder by normal means (I have "soldered" alumina crystals by diffusion bonding, this is difficult). Glass and stainless steel may also be soldered by special techniques.

However I would recommend using a wood screw and star tag washer to make connection to the aluminium, but even then you may get a poor connection to the aluminium. One problem soldering thin aluminium is it is low melting point, you can melt it with a hot soldering iron.

Aluminium is a good shielding material, and one of the reasons the best amp chassis are made of aluminium.

[davmac]

Originally Posted by jefrs

It is fairly easy to solder aluminium. You have to abrade its surface under a layer of grease or oil, and solder through the grease.

Fascinating stuff! I'd always assumed it was out of reach for a hobbyist like me but I might give that a go.

Where I have shielded guitars I've used the copper slug repellent tape from a garden centre. It is a third of the price of the stuff you buy from electronic or music stores and works a treat. Mind you, since I found out about twisted pair wiring I haven't felt the need to shield a guitar. For anyone suffering from interference problems I'd recommend that as the first step because it is so easy to do and doesn't require any additional materials.

[MORCILLO]

I shield with cheap aluminium tape (as used in plumbery) and make the conections with cooper tape from StwMc, works perfect and saves money.

[dman]

Originally Posted by DavidP

I'd love to try that electrodag paint but its really shot up in price! (seehttp://www.ebay.com/itm/Guitar-Condu...item4cfa5cf294)

It used to be $12 + S&H, which ran about $3 or $4. It's free shipping now, so while it has gone up, it's not by that much. It DOES work great, though!

[chrisgblues]

Originally Posted by David Collins

Yes, aluminum tape works fine. As others mentioned, copper tape with conductive adhesive may be preferred to easily achieve reliable continuity between strips, but if you tuck and fold under tabs every few inches on aluminum tape, or join them with small brads or staples, you can get good and reliably continuity between strips as well.

^THIS^
I thought I was the only one doing that! Ha! Guess I'm not so smart after all.

I've shielded several guitars with the same roll of 2.5" aluminum tape I bought at Home Depot a couple years ago for $5.99. Works great, but like he said, just cut little tiny tabs every few inches and tuck them under (1/8" or 1/4" tabs) and then overlap each piece of tape by the same width as each tab and you will get a nice connection between each piece.

Cheap - easy - dependable.

You can also shield the inside of any cheap plastic stomp box you may have kicking around at home.

JMHO. YMMV.

[David Collins]

Yeah, I know contacts like tabs folded over which are not mechanically connected or soldered may not seem ideal, but I've never had a problem with loosing continuity. If you overlap the layers of tape and cut/fold a tab under every few inches, you will have enough redundant contact points that the odds of all of them loosing contact is really quite slim. Then if you want to be extra sure, you can drive a few little brads in at the overlap points, but I've never found this necessary, and have never lost continuity between layers.

That said, I haven't used the tape method very often. If you're just doing one or two guitars for yourself, aluminum duct tape can be a quick and cheap method. For me, time is money, and it ends up cheaper (and looks more professional) to simply mask and spray on a few coats of nickel paint that it is to custom cut, fit, and install a tape in to complex shaped cavities. Mask and spray, let dry, and reinstall electronics. Quick, effective, and looks clean too.

[cband7]

Long ago (early 80's) we used to shield our electronics with an industrial silver spray provided by Uncle Sam. I just looked it up and for a 1.5 kilogram can the price is almost $3000 !!!

Think I'll stick with the copper tape!



.

[robt57]

Originally Posted by cband7

Long ago (early 80's) we used to shield our electronics with an industrial silver spray provided by Uncle Sam. I just looked it up and for a 1.5 kilogram can the price is almost $3000 !!!

yea, but that is the tax payer price [ducking]

[MORCILLO]

Im not a expert, but there are "shield" paint and "conductive" paint, with this, you can fix circuit boards and things like that, and is very expensive.

[jefrs]

If you have a Fender Candy Coat, it's already shielded.

I seem to remember making aluminium "boats" for shielding stuff. Take a look in the back of a shielded Les Paul cavity. Aluminium is soft, thin sheet (not foil tape) can be cut with scissors and bent to shape in your fingers and by pushing it into the hole with a little persuasion.