Installing P90s in a Trem-routed Strat

[Runewalker]

Could not quite decide where to put this as it relates to pups and installation. But the question is mechanical installation opposed to wiring, so Luthiery wins, I guess.

The wood between a pup rout and the trem spring cavity rout on a Strat style guitar bod is quite thin 1/4" to 3/8s. [Soapbar] P90s are typically in a back-routed control-cavity bod, with no trem spring cavity -- then the pups are wood screwed through the pup body directly into the pup cavity, with a foam "spring' for height adjustment. That presupposes enough wood meat to absorb the varying depth of the screw travel.

This extra meat is missing in trem-spring cavity Strat. You could just sink the wood screws in the thin wood, adjust the pup height, then snip any wood threads that extend below, but that seems un-craftsman-like. Also that thin, almost veneer-like spread of wood to hold 2-4 screw threads seems wholly inadequate.

A couple of options I have considered:

1. Use machine screw bushings. These are similar to the bushings used on Gibson bridge components, that sink into a pilot hole then provide metal machined threaded holes for the posts of the TOM and stop tail-piece. The difference is they are externally threaded and screw into the pilot hole opposed to being pressed. Then machine screws would be used for the pup mounting hardware. Requires precision alignment, and may only marginally improve the stability, since the fundamental problem of inadequate wood depth is not addressed.

2. Establish the height of the pup in final position, establish the distance between the pup rout floor and the pup plate, then place and glue a wood filler piece to give more wood depth used to secure the pup. How? Hmmmm.... Requires a lot of trial and error to establish the optimum pup height since the solution is permanent and invariable. Once determined then mark the pup at the body interface then conduct the measurement exercise. Better be durn sure you are content with the pup height. Don't care for the inflexibility of this solution. But have always been intrigued with the mfgs. who claim that the hard mounted pup renders a more stable sound.

3. Fill the trem spring cavity with wood, block the trem into a hardtail equivalent. Then you have plenty of wood for the pup screws. OK, but forget surf warbles.

So none of these seems quite optimal.

JH asked me about fabbing some plate tabs like a humbucker, but that will not work because the strat pickgaurd barely has any plastic left for the single coil tab screws at the neck pup, and the form-factor of the p90 is even bigger than a single coil length. No extra room for tabs on a p90 and the retention of a conventional strat pickgaurd. That would also require routing extension, and I am already going to have to do some routing, at least on the mid position. Don't have any pix, but look at your strat pickgaurd neck hole and you will see what I mean about the sizing issue and the pickgaurd.

Any one had an actually executed solution to this dilemma, or ideas? And no, the answer is not to use the humbucker form-factor "P-90s" (which aren't) or the Strat single coil "P-90s" (which also arn't).

Why P90s on a strat? Because I can.

RW

[dunkelfalke]

so, what about a custom pickguard with more area?

i am thinking of a pickguard more or less along the lines of my revelation (maybe without the extra horn):



you would actually need just a bit different shape

[Runewalker]

dunkelfalke said:

so, what about a custom pickguard with more area?

i am thinking of a pickguard more or less along the lines of my revelation (maybe without the extra horn):

you would actually need just a bit different shape

Sure that is a workaround, but doesn't address the actual problem. That also presumes fabricating an additional bottom plate with earbrackets (not to be confused with P-90 'dogears' --- adaptor brackets for soapbars is what we are talking about here) then more aggressive routing to accomodate the tabs. Besides once you go custom pickgaurd you abandon the Strat JuJuMoJo.

Lots of additional work and expense and no or at least different mojo.

[dunkelfalke]

i see. then it would be the second solution i think, with the difference, that you take a thin wood filler so that you have to use its wood and the wood of the guitar combined.

[RJB]

Tap the mounting ears of the P90 for a machine screw and use the spring/tubing mount from the pickguard like a normal strat. Like they did with the Squier Tele Custom II

[Runewalker]

No 'mounting ears' on soapbars. Mounting screws go throught the mid line of the pups.

Also, strat pickgaurd is not large enough at the neck slot to aborb the additional distance involved with mounting ears, if soapbars had them. Finally, as mentioned in previous entries, mounting ears would require addition, undesired routing of the body.

See the first post:

dunkelfalke also suggested a custom pickgaurd to cover additional routing and mouting ears. Violates the strat mojo which is already strained with the P-90s. But, gotta do it.

Thanks for thinking about this challenge though. Never seen that pickgaurd on a Tele, which seems to have some Jag references.

[UnklMickey]

"Any one had an actually executed solution to this dilemma, or ideas? And no, the answer is not to use the humbucker form-factor "P-90s" (which aren't) or the Strat single coil "P-90s" (which also arn't).

Why P90s on a strat? Because I can."

well that remains to be seen at this point doesn't it?

it's not that i don't think you can. just doesn't seem to be an obvious way to make it easy.

so, if the thin "internal tonewood layer" is not structurally sound for mounting the soapbars, could you fab. a metal plate with machine screw taps for the soapbar screws and countersunk holes to mount the plate to the thin wood layer?


of course, it might take a bit of experimentation to find the right "tone-metal" to match well with the existing wood.

LSH...

unk

[Runewalker]

unklmickey said:

"Any one had an actually executed solution to this dilemma, or ideas? And no, the answer is not to use the humbucker form-factor "P-90s" (which aren't) or the Strat single coil "P-90s" (which also arn't).

Why P90s on a strat? Because I can."

well that remains to be seen at this point doesn't it?

it's not that i don't think you can. just doesn't seem to be an obvious way to make it easy.

so, if the thin "internal tonewood layer" is not structurally sound for mounting the soapbars, could you fab. a metal plate with machine screw taps for the soapbar screws and countersunk holes to mount the plate to the thin wood layer?


of course, it might take a bit of experimentation to find the right "tone-metal" to match well with the existing wood.

LSH...

unk

Hey, I think you are on to something. That seems eminently workable. Will have to use brass to avoid the interference with the flux field, I suspect Alcoa to be too soft. Any other tone metal I am missing that will take the taps.

I could either epoxy it in or even bolt it, depends on which method conveys the best tonemetal emissions.

See, brilliance abounds. But I thought for sure I would get a StratJuJu, UglyJuJu speech.

Thanks Unk

[UnklMickey]

runewalker said:

... But I thought for sure I would get a StratJuJu, UglyJuJu speech....

been there, done that, burned the t-shirt.



brass would be my choice. but a non-magnetic stainless alloy would work too, if you don't mind the hardness during the fabrication.


unk

[servant]

runewalker said:

Never seen that pickgaurd on a Tele, which seems to have some Jag references.

The first time I saw that type of pickguard was when I owned a (probably 1972) Telecaster Deluxe (kind of a Les Paul wanna-be as far as pickups, switch and volume/tone pots go). Except for the fact that mine had two humbuckers and a Strat headstock, it looked a lot like the Squier Tele shown above. That's the first time I saw that pickguard.

[Runewalker]

The first time I saw that type of pickguard was when I owned a (probably 1972) Telecaster Deluxe (kind of a Les Paul wanna-be as far as pickups, switch and volume/tone pots go). Except for the fact that mine had two humbuckers and a Strat headstock, it looked a lot like the Squier Tele shown above. That's the first time I saw that pickguard.

Thats a pretty large landscape of toneplastic.

[pollyshero]

Here's a thought - have you been able to determine where the mounting screws will break through into the trem cavity? If so, will the location allow you to epoxy dowels between the trem springs (red dots) without interfering with the spring?

3/8" dowels would probably work - 1/2" if the mounting screws were too big. Epoxying them would certainly be enough since there really wouldn't be any load on them.

Of course this only works if you only use 3 springs…

Just an idea. Good luck!

[Runewalker]

Fellow Texan UnderDawg:

I did actually think of that or something similar, I just don't want to get that Spronggggggg sound from some Iron Butterfly intro if I get it too close to the spring. And actually I am a 5 spring guy, or at least 4 because I like big ol' 'strangs'.

The other thing is that the 2 screws that hold the soapbars are fixed in their allignment, so I am not sure where they will pop out in the spring cavity.

But I am not forgetting this idea, as it may be workable in some form.

RW

[sumgai]

RW,

unklmickey has it right, as far as he goes. (hehehe) Where you want that metal plate is in the spring cavity itself! Now you can use plain sheet metal (inexpensive), it can be screwed down to the thin wood in several places that have more strength (unrouted areas between the pickups "above"), and when you drill through from up above, you'll hit solid metal for your machine screws instead of having to use wood screws - no bushings or inserts. ;D


sumgai

[Runewalker]

Posted by sumgai on Today at 8:59pm
RW,

unklmickey has it right, as far as he goes. (hehehe) Where you want that metal plate is in the spring cavity itself! Now you can use plain sheet metal (inexpensive), it can be screwed down to the thin wood in several places that have more strength (unrouted areas between the pickups "above"), and when you drill through from up above, you'll hit solid metal for your machine screws instead of having to use wood screws - no bushings or inserts. sumgai

SG:

Sheet metal is ferrous and I would have concern about flux eddy probs, even with the 3/16 wood "insulation".

Also sheet metal screws are course threaded and not particuarily secure. To get enough bite on the sheet metal screws mean sending the taper point past the sheet metal to bite the full diameter of the screw, which means protubering points into the dynamic path of the virbrato springs, catching them and going Sprrroooiniiinnngggg.

Many issues with that approach.

There are hardware nuts called Tee Nuts that are a little vicious looking:

www.mcfeelys.com/query.asp?query=tee+nuts&keyword=tee_nuts&rkgsource=google


and these are too big and the wrong metallurgy, but something in this direction, smaller, in brass, and perhaps a little moderation of those nasty brad points might work.

[pollyshero]

Rune,

I actually like the plate idea better, but the dowel thing popped into my head & it seemed like it would work provided one was a 3-spring man. By the time I had the drawing done & posted I was sick of the idea but I'd spent an hour or so on it.

It was kinda like beer goggles - by the time you focus it's either a case of "might as well...", or it's too late anyway.

[sumgai]

RW,

unklmickey has it right, as far as he goes. (hehehe) Where you want that metal plate is in the spring cavity itself! Now you can use plain sheet metal (inexpensive), it can be screwed down to the thin wood in several places that have more strength (unrouted areas between the pickups "above"), and when you drill through from up above, you'll hit solid metal for your machine screws instead of having to use wood screws - no bushings or inserts. sumgai

SG:

Sheet metal is ferrous and I would have concern about flux eddy probs, even with the 3/16 wood "insulation".

Also sheet metal screws are course threaded and not particuarily secure. To get enough bite on the sheet metal screws mean sending the taper point past the sheet metal to bite the full diameter of the screw, which means protubering points into the dynamic path of the virbrato springs, catching them and going Sprrroooiniiinnngggg.

Many issues with that approach.

There are hardware nuts called Tee Nuts that are a little vicious looking:

www.mcfeelys.com/query.asp?query=tee+nuts&keyword=tee_nuts&rkgsource=google

and these are too big and the wrong metallurgy, but something in this direction, smaller, in brass, and perhaps a little moderation of those nasty brad points might work.

In quoting the previous messages, I emphasized my first statement, machine screws, not sheet metal screws. The idea was, once you drilled your pilot holes, you tapped them to fit the long machine screws, said long screws to be trimmed flush once the overall pickup height is determined. And don't worry about 'eddy currents' and such, unless you're using some really powerful magnets.

But you could use Tee-nuts, they're available in small sizes too, and again, once you drill a pilot hole, the rest is easy. But don't knock down those brad points, they're what keep the nut from turning in the wood when you're trying to twist the screw. Ask me how I know! ;D

McFeely's is a good place to deal with, but the shipping fees will kill your wallet. I'm sure you'd be better off going down to your local hardware store to get a pair of 10-32 or 8-32 nuts. In fact, take the P-90's current screws, or even the pickup itself, down there to make sure you get the right size. Remember, you can always cut a long screw short, but it's pure hell trying to make a short screw longer!


sumgai

[Runewalker]

UD:

I actually like the plate idea better, but the dowel thing popped into my head & it seemed like it would work provided one was a 3-spring man. By the time I had the drawing done ....

Actually I immediately noticed the rendering and thought, man ol' UD put some effort into this or perhaps you had some drawings from a previous planning session. The over and above effort is appreciated.

In fact, while we have knocked on a number of doors, and explored some closed canyons, this has helped alot. Great group to brainstorm with, perhaps the only group of humans that would bother. Have you ever tried to discuss, in an animated voice, the pros and cons of System Series, Parallel wiring punctuated by OoP options to someone who doesn't live there. Great hypnosis technique. Get glassy-eyed fast.

sg:

I emphasized my first statement, machine screws, not sheet metal screws ...

Whupps, missed that. None-the-less it was a pictorial image. I especially enjoyed the Spppprrrroooiiinnnngggg.

there are some things I like about shelling the spring cavity with sheet metal, but the only other concern I might have is that I do not think the thickness is enough to establish a meaningful depth for tapped threads. The machine screw would be grabbing the thickness of the SheetMetal as a single thread. I could use a nut and washer but that would be a surface nodule.

The tee-nuts popped in my head actually last night as I was responding with an incorrect but visually rich assertion.

And assuming I can find the right size, and that was not successful last night, that seems easy and workable. I am with you on the brad tips, but may trim them if the are too aggressive. I would probably also use a thin bed of epoxy, just for a little belts and suspenders action.

I seem to find them only in stainless or zinc coated steel.

A couple of questions. The soapbar P90 mounting screws go through top case, the center of the bobbin then into the base metal plate. That is likely to touch the QTB body shielding, and certainly will when the new mounting screw move through the TEE-nut or other solution.

So 1) is there an issue with the Tee nuts being made of steel. I just assumed you did not want any magnetic distractions. SG seems to be uncerned about that?

2) Do I ground that plate or insulated it, and the other connection to the body mounting system chosen?

Finally, sg:

McFeely's is a good place to deal with, but the shipping fees will kill your wallet. I'm sure you'd be better off going down to your local hardware store to get a pair of 10-32 or 8-32 nuts. In fact, take the P-90's current screws, or even the pickup itself, down there to make sure you get the right size. Remember, you can always cut a long screw short, but it's pure hell trying to make a short screw longer

starting with the word McFeely's and moving through the lively prose that follows provides a wealth of digressions, that I will nobly rise above, but I guarantee nothing from the Unkster.

[UnklMickey]

runewalker said:

...I seem to find them only in stainless or zinc coated steel.

A couple of questions. The soapbar P90 mounting screws go through top case, the center of the bobbin then into the base metal plate. That is likely to touch the QTB body shielding, and certainly will when the new mounting screw move through the TEE-nut or other solution.

So 1) is there an issue with the Tee nuts being made of steel. I just assumed you did not want any magnetic distractions. SG seems to be uncerned about that?

2) Do I ground that plate or insulated it, and the other connection to the body mounting system chosen?

Finally, sg:

McFeely's is a good place to deal with, but the shipping fees will kill your wallet. I'm sure you'd be better off going down to your local hardware store to get a pair of 10-32 or 8-32 nuts. In fact, take the P-90's current screws, or even the pickup itself, down there to make sure you get the right size. Remember, you can always cut a long screw short, but it's pure hell trying to make a short screw longer

starting with the word McFeely's and moving through the lively prose that follows provides a wealth of digressions, that I will nobly rise above, but I guarantee nothing from the Unkster.

if you're concerned about magnetic permutations, the stainless alloy in those t-nuts might be non-magnetic.

ground the baseplate of the pickup to the shielding in the same general area of the mounting screws. then you won't have any concerns whether or not the mounting screws contact the shielding.



McFeely digressions? what? who? me?

okay, who am i kidding?:


"Remember, you can always cut a long screw short, but it's pure hell trying to make a short screw longer!"


that's not what she said, actually quite the contrary!

[sumgai]

Rune,

And assuming I can find the right size, and that was not successful last night, that seems easy and workable. I am with you on the brad tips, but may trim them if the are too aggressive. I would probably also use a thin bed of epoxy, just for a little belts and suspenders action.

Belt and suspenders, good - - nut rotating uselessly in wood, bad! Good plan on your part.

..... but I guarantee nothing from the Unkster

Seeing the infamous Unkster post even as I scribble this obviates any response I could possibly come up with! ;D

Good luck with the project!


sumgai

[pollyshero]

Hey - if you can find it, check out the Loverboy video for "When it's over" (I saw it on VH1 yesterday - Watch "Big 80's" if you dare!). You'll see a Strat style with P90's - looked COOL.

Dang. Now I want one too...