Wood Flat Stock?

[David Schwab]

Alien technology at its best! Just ask Possum...

Apparently the whole project was originally funded by Philips Industrial Electronics, who was going to be the ones marketing the pickups, and then they decided to not get into that market.

[LtKojak]

Apparently the whole project was originally funded by Philips Industrial Electronics, who was going to be the ones marketing the pickups, and then they decided to not get into that market.

Thank God they didn't do it... can you image what kind of damage would've costed to all p'up makers, Boo-tick and non?

I've just got goose bumps...

[jonson]

Partialy handmade, thats the molding. Machine made part, thats the coils. Coils baked " thermofusing" Thats self bonding wire using a current to cook it.
Modern epoxies and polyurethanes don't show join lines in slow successive pours. Could be fun having a go at one of these. Should have floated a name in the top layers allthough they speak for themselves.

[David Schwab]

Modern epoxies and polyurethanes don't show join lines in slow successive pours.

I figured it has to be done in stages to hold the various parts in place.

He might even cast the coils and magnets as an assembly and then add them to the rest.

I had a few of them loaned to me to check out. I was surprised how yellow the epoxy had gotten.

[jonson]

Gotta be right there, being neo's (done one at a time or just glued in place.) You say gone yellow and that screams polyurethane to me as it's far quicker to cure, allthough clear casting poly is a fairly recent material, unless he's hotbox curing epoxy. Casting with screws in and removing to leave thread or drilling and tapping after, both work. And he's probably reading this and going "your way off baby" but there's more than one way to skin a cat.

[David Schwab]

I believe he's casting with the screws in, as I have his book, and that's what he always did. it also looks that way when you see one up close. The holes don't exit out the bottom.

The part that puzzles me is each coil has a neo bar magnet. Just doing that requires that you stick them to something so they don't flip around and stick to each other.

They don't touch the coil, but are closer to the bottom. They also don't touch the poles pieces, which are a series of set screws.

So getting the whole assembly to not self destruct as you are trying to get it into the mold is a mystery to me! The coils also have their series connection via a short length of bare solid wire.

There are bubbles in odd locations, so maybe some parts were pre cast on their sides.

He says he uses epoxy, so I'll assume that what they are.

Here's a shot I took of one on top of an EMG style cover shown for size.

[Bruce Johnson]

It looks to me like the screw holes are drilled and tapped down from the top after the epoxy is cured. You can see how the threads go all the way to the bottom of the hole and taper at the tip just like the tip of a spiral point tap.

My guess is that he pre-epoxies the coils and magnets together in accurate alignment in some jig, then sets the whole assembly down into the mold for the "overcast" of epoxy. The cast block then goes into a drill fixture for the screw holes, and then under a power tapping head set at a fixed depth. That's how I'd do it.

You're right about epoxy yellowing. The old 1960's Ampegs that I specialize in have a cast epoxy pickup coil down in the "mystery" pickup. After 43 years, they're about the color of a puddle of yesterday's hound dog piss. ( I have an old hound dog, so I've done accurate color comparisons.)

[automan]

What do you guys know about this bondable wire. I have read about it, but never thought to use it. Seems like you would be half way turning the inductor coil into a capacitor. Or am I missing something?

[David Schwab]

It looks to me like the screw holes are drilled and tapped down from the top after the epoxy is cured. You can see how the threads go all the way to the bottom of the hole and taper at the tip just like the tip of a spiral point tap.

I no longer have the pickup, but I'm not sure if they are tapering, or if it's the way the light is effecting it. If you zoom in on the full size image, you can see that the threads look red near the bottom, where the light is coming in from under the magnet, refelecting off the wire.

But they do look tapered, so they might be. How would he get the holes clear from debris since they are not through holes?

My guess is that he pre-epoxies the coils and magnets together in accurate alignment in some jig, then sets the whole assembly down into the mold for the "overcast" of epoxy. The cast block then goes into a drill fixture for the screw holes, and then under a power tapping head set at a fixed depth. That's how I'd do it.

That seems reasonable.

You're right about epoxy yellowing. The old 1960's Ampegs that I specialize in have a cast epoxy pickup coil down in the "mystery" pickup. After 43 years, they're about the color of a puddle of yesterday's hound dog piss. ( I have an old hound dog, so I've done accurate color comparisons.)

That was one of his early pickups I had, but it wasn't that old to have yellowed that much. The set of Jazz sized pickups I had didn't look that yellow.

[Bruce Johnson]

He could be casting the threads in place, by having an array of long threaded screws coming up through the bottom of the silicone mold, from a metal base plate underneath. But, that sounds like more labor and trouble per pickup than just drilling and tapping them afterwords.


Cleaning out the tapped holes can be as simple as blowing them out with an air hose. You could also use a "thread roller", which is a fluteless tap that forms the threads rather than cutting them. They don't make any chips. I don't think I've ever tried a thread roller in cast epoxy, but it should work.

[David Schwab]

He could be casting the threads in place, by having an array of long threaded screws coming up through the bottom of the silicone mold, from a metal base plate underneath. But, that sounds like more labor and trouble per pickup than just drilling and tapping them afterwords.

I thought of that, but I think you are correct about them being drilled. The more I thought about it, I remembered that I've seen photos of some of the early ones, where the holes were not perfectly aligned.

[tedmich]

IMHO threaded pole pieces are silly; very few (if any) players fine tune each string. I had 44 Allen screws in my 2 x SD22's for a couple decades and never saw any benefit to twisting them. Course I don't have golden ears... HC reviewers say the Qtuna's deaden the sustain cause they grab so hard, which makes sense if he's using anything but TINY NdFeB's. Stronger mags are not the answer. Holdsworth maintains 6k winds with weak magnets have better sustain than typical 12-20k HBs.