Question about pickup magnet diameter and flatwork

Discussion in 'Tele Home Depot' started by TenaciousP, Oct 6, 2021.

  1. TenaciousP

    TenaciousP Tele-Holic

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    So I notice most places sell .187 and .195 diameter magnets and fiberboard flatwork with matching hole sizes. I like shopping at Philadelphia Luthier for a lot of things, but I notice they only sell flatwork in .187 hole size. So I’m wondering, is it absolutely necessary to have .195 flatwork for that size magnet or will the fiberboard give enough to press them into .187 holes? I feel kinda dumb asking this question because as an engineer, I want to say it’s a bad idea. But I’m curious if anyone has ever tried it. And what were the results.
     
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  2. tubedude

    tubedude Tele-Holic Silver Supporter

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    I'll bet if you force 6 of them in the flatware will eventually buckle.
     
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  3. crazydave911

    crazydave911 Doctor of Teleocity

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    I use neodymium magnets now 1/4" diameter but only glue them to the bottom of steel slugs which old ceramic pickups seem to provide plenty of. If I was still in alnico I would find the correct flatware or get/make a punch and do my own flatware which I always have anyway. Which doesn't help you at all, sorry lol
     
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  4. TenaciousP

    TenaciousP Tele-Holic

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    Yea, would be worried the fiberboard would warp or get mushed up around the pole piece. I just find it strange that a place that has so many great parts would have both magnet sizes, but flatwork for only the smaller size. It made me wonder if there was something they knew about assembling fender style bobbins that I didn’t know.
     
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  5. TenaciousP

    TenaciousP Tele-Holic

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    Interesting info about pickup building Dave! And it made me laugh when you admitted that it doesn’t help me with my question. Ha Ha!:lol:
     
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  6. crazydave911

    crazydave911 Doctor of Teleocity

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    Hey, just being honest lol, usually gets me in trouble :lol:
     
  7. Lowerleftcoast

    Lowerleftcoast Friend of Leo's

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    You can ask if Philadelphia Luthier has the fiberboard for the larger diameter. I have embiggend the hole with a rat tail file on a set I put together. Don't try to force it no matter how tempting. hah.
     
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  8. old wrench

    old wrench Friend of Leo's

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    Ream the holes out :)

    Fiber-board reams pretty cleanly with a sharp reamer ;)


    .
     
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  9. RickyRicardo

    RickyRicardo Friend of Leo's

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  10. epizootics

    epizootics Tele-Meister

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    With Fender-type pickups, it is quite typical to press your magnets into holes of a slightly smaller diameter. The difference is about 0.008" (0.2mm). This will keep the whole assembly rigid enough not to require glue to keep the magnets in. (I still add a small fillet of CA glue on the inside of the bobbin 'cause I'm a belt & braces kinda guy - just an extra insurance, like wrapping the magnets in kapton tape prior to winding.)

    You can make simple jigs to simplify the assembly of the bobbin, typically a spacer the thickness of your winding and another one with six holes drilled 0.02" larger than the magnet diameter to press the top flatwork on in one go. This prevents forbon from being pushed up and out when the chamfered end of the magnets is pushed through.

    While with this little jig the top can be banged on with a hammer, you still want to press the magnets in at the bottom. I use my drill press for that and it works fine.


    In your case, though, it depends on what the seller calls '0.197 flatworks'. It might mean it has been drilled to an actual 0.197", which is not ideal because even the bigger, 0.197"-diameter magnets would be too loose in there, or it might mean it has been drilled to 0.185", which would be fine for 0.197" magnets. Same for '0.185 flatworks', which should be drilled to 0.177". Alas, not all manufacturers are aware of that necessary offset when they get their flatworks laser-cut. So the safest thing to do is to email them before ordering & ask them about the actual diameter of those holes.

    I never ordered flatwork from PhilaLuthier, but ToneKraft get theirs cut with the right diameter. But depending on the season, they can be hard to deal with. Even pre-Covid, there were tales of some orders taking ages to be shipped.
     
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  11. guitarbuilder

    guitarbuilder Telefied Ad Free Member

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  12. Ronkirn

    Ronkirn Doctor of Teleocity Vendor Member

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    You have spoken wisely..



    and dawggone it... now the secret's out...

    r
     
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  13. Red Ryder

    Red Ryder Tele-Meister

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    Just because you're an engineer doesn't mean it's a dumb question.
    I'll bet you have a lot of fun driving a train.
     
  14. Old Deaf Roadie

    Old Deaf Roadie Friend of Leo's Gold Supporter

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    Enlarging a hole by .013" should be a walk in the park for an engineer in my crazy, convoluted way of reasoning. I'm thinking find the nearest drill diameter that is undersize and have at it, or order a reamer from MSC or McMaster-Carr.
     
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  15. Ronkirn

    Ronkirn Doctor of Teleocity Vendor Member

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    c'mon guys, a set of flat work costs about a buck 50... just order the correct size... jeezus... if you try to poke a magnet that's too darn large through a hole that too darn small.. nothing good is gonna come from it.... ya might as well just order a few cheep Chinese pickups instead...

    as my Dad taught me as a Kid, while he was making Mahogany Boats... "Any thing worth doing is worth doing right, and funny how there never seems to be time enough to do it right, but there is always time to do it over." He would always get me with the "time to do it right" logic when I tried to skimp on mowing the lawn.... He would get a lawn chair, sit it in a shady spot with a couple of cool ones.. and watch me mow the whole darn thing over.... While Mary Lou was waiting...:p

    the hole needs to be precision for to apply enough pressure to hold the assembly together... Glue it together.. Looser.. force the wrong magnets into the wrong holes.. Looser... Are ya making the pickup to make one that's better, or just to make a mess... do it right..
     
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  16. TenaciousP

    TenaciousP Tele-Holic

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    I was actually thinking of ordering from tonekraft. Although, as @epizootics mentioned, I have heard of people having some difficulties dealing with them. I’ll probably order from them anyway…
     
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  17. RickyRicardo

    RickyRicardo Friend of Leo's

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    The only problem I've had with them is a bit of a delay in shipping as I think they build to order but not sure. Otherwise I'm pleased and their stuff is really good quality.
     
  18. TenaciousP

    TenaciousP Tele-Holic

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    I hear ya! I’m all about doing things right the first time. In the end, I plan to get the flatwork and magnets that match. I’m not trying to be cheap or anything like that. I certainly don’t want to have to ream any holes out to make it work if I can just buy what works as is. I was honestly just curious if it was possible. I know there has to be some degree of interference fit, but I didn’t know if a .195 magnet into a .187 hole was too much interference. You know how sometimes everyone thinks something can’t be done or is a bad idea because it’s what they’ve always been told by marketing hype, etc… I was just wondering if this might have been that sort of thing. Once again, my gut feeling is that it really is a bad idea, but I have never personally tried it. And I was just curious if anyone around here had.
     
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  19. TenaciousP

    TenaciousP Tele-Holic

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    Of course I do! :lol::lol::lol: Woo Woo!
     
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  20. Ronkirn

    Ronkirn Doctor of Teleocity Vendor Member

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    You can bet someone has.. it's just that guys rarely start a thread about how they screwed the pooch on some bone headed idea in the first place idea...

    Like, " I sawed the neck off an old LP and nailed it onto my Squire Tele.. but I used glue too, so it's a set neck... now the actions making it buzz and rattle.. and I'm not sure how to set the intonation. I leveled the frets with my carpenter's level, by propping up the headstock until the bubble was in the middle... but I don't see how that does anything for the thing,. But it is very lightweight and resonant... sounds like a Hornet's nest when I strum it unplugged."
     
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