#407

So I finally got around to testing with the shit P90-style pickups I got off ebay and I can’t seem to solder to the protruding screws out of the bottom.

I ordered two different types. Here are closeups of the bottom:

IMG_0531 2
IMG_0531 24032×3024 1.63 MB

IMG_0533
IMG_05334032×3024 1.58 MB

I was initially hopeful that the threading on the black pickup would be enough to screw a couple thing bolts onto there to clamp wire down that way. They are way too short, even when screwed “down” as far as is reasonable.

I tried soldering some thin gauge wire to it, but I couldn’t get it to stick at all, and then I started worrying about hitting the Curie temperature since the poles are supposed to be magnetic.

The more cream colored ones protrude quite a bit more, but don’t have much to hold on to.

In the past I’ve done some dodgy work with conductive adhesive/paint, but that seems a bit janky in general.

I also thought some kind of speaker terminal things might work, with just a friction/mechanical connection. It’s cutting it a bit close as I want to keep the wires electrically isolated from the brass base plate, so I can’t push them down too far.

Anyone have any thoughts/suggestions on how to attach wires to these?

(the intended use will be a mini guitar-esque percussive instrument which also doubles as a 6x6 switch matrix(ish) thing so that as you press the individual strings to the poles, you close connections on a breakout board. so my intention here is to be able to run wires from the bottom of the poles to the rest of the hardware)

#408

I often find it difficult to solder to contacts with shiny chrome plating, but it’s much easier when it’s abraded or removed. Try a little sandpaper or a abrasive tool with a Dremel type rotary tool and the solder might take.

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#409

That’s a good shout!

I still worry about demagnetizing the poles though.

#410

The screws themselves should not be magnetic, there should be two bar magnets in the pickup that provide the magnetic field.
Buy longer screws?

If the screws are the only source of magnetism then you could easily clip a bar magnet or neodymium to the back depending of the desired tone.

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#411

That’s true actually. There’s two bar magnets running along side them, so I guess the poles are “just screws”.

Longer screws are a great idea! I’ll test some tomorrow (hopefully they are metric and not some odd/imperial things)

The magnet option is kind of interesting too. I guess it’s a matter of testing, but I could conceivably just use some ferrous bits of metal (nuts or something) to magnetically hold onto the poles. Not super sturdy, but it may be an option too.

#412

Rereading your intentions, it occurs to me that it might be better to separate the switching matrix from the pickup entirely. Most of the time, if the pole pieces are high enough to be able to be hit by the strings they are too high anyway. Using the same principle, you could mount an insulated block just before or after the pickup with adjustable contacts (machine screws) and have them threaded into nuts set into the insulated base, solder your contacts to the nut instead of the screws?

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#413

I could have been clearer, but I think part of what I’m after is that “floppy string clunking against a pickup pole” sound. That kind of thunk/thud you get when the strings are really loose.

My intention is having something no more than 8-10" or so with regular(ish) gauge strings so they are super droopy.

I don’t know if it will work exactly like I’m thinking, but what I’m imagining is using those thunk sounds in conjunction with the switching that is tightly synced (heading to a modular) to create a (hopefully) interesting percussion-ish instrument.

On a super positive note, the screws/threads appear to be M3 and I have some decently-lengthed bolts on hand. I’m sure that will change the tone in some way, but given my idea, I don’t think it will matter too much.

Knowing I have the bolts for this, I can hopefully whip up an initial test/prototype and see if it all works how I think.

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