Using Magnets as the Blades in a Soapbar Rail HB?

[Novorca]

I am considering building a soapbar blade style HB. My question is - could the blades be magnets? (i.e.,similar to Strat magnetic pole pieces) I can't see any reason why not. Just wondering if there's any particular reason this wouldn't be worthy of some R & D.

[belwar]

I am considering building a soapbar blade style HB. My question is - could the blades be magnets? (i.e.,similar to Strat magnetic pole pieces) I can't see any reason why not. Just wondering if there's any particular reason this wouldn't be worthy of some R & D.

No problem at all - it should sound great

[Novorca]

Nice - so here's my next inquiry. The bobbin of a P90 looks as if it is usually 1/4" (inside dimension of flat-work). So if I add a little bit to that, then we could say that the overall height of a P90 bobbin is somewhere around 7/16" give or take. The conventional construction has the magnets underneath the bobbin adding to the stack height of the pickup. Add the base-plate to this and the overall height of the pickup grows to somewhere between 5/8" and 3/4" - or something like that. So then - using blade magnets as poles eliminates the magnets under the bobbin. This would reduce the the overall height of the pickup if the bobbins are keep at the 1/4" inside dimension. This would make a rather thin pickup so 1) is that a problem? or 2) can the bobbins be taller to make up the difference? I think having a taller bobbin might allow for some interesting results. Any thoughts on changing bobbin heights? Or is this one of those things where you can pretty much do what you want to do and still have a reasonably viable and possibly nice pickup?

[copperheadroads]

One thing is ,a typical soapbar has it's mounting screws through the center (& where your bar magnet will be now ) so you will have to mount it some other way.

[copperheadroads]

The old Gibson melody maker & some sg's had pickups the used bar magnets in the center of the bobbin like your idea ......they sounded like poop
I got a set here
Shit i just made an order today & i forgot to order some of these ,I wanted to try that with myself in a different design
Mojo Pickup Parts » 2115441 Mojotone Strat Flatwork Top and Bottom (for 2.180 long bar magnet)

[Novorca]

One thing is ,a typical soapbar has it's mounting screws through the center (& where your bar magnet will be now ) so you will have to mount it some other way.

True. However, the design I am thinking of is a humbucker. So it's going to have 2 blades. If I'm not mistaken, I'll have a lot of real estate in the middle to put the mounting screws through. It will be a lot like the JBE soapbars.

[copperheadroads]

OH ..Sorry ,I guess I missed the humbucker part
So the screws will be to keep the looks traditional ?
When i get some Idle time I'm gonna work on a sidewinder version of the P-90

[Stealth]

I am considering building a soapbar blade style HB. My question is - could the blades be magnets? (i.e.,similar to Strat magnetic pole pieces) I can't see any reason why not. Just wondering if there's any particular reason this wouldn't be worthy of some R & D.

If I recall right, Firebird and Thunderbird pickups are built the exact same way.

[FunkyKikuchiyo]

If I was embarking on such a thing, I'd start by getting a gauss meter. Using steel blades puts you on a path of a known amount of gauss because you're working with materials and dimensions that have been known to work in guitar pickups already. If I'm going to design a whole pickup around just a magnet, I'd want to be able to make a good judgement of what size magnet I want so I don't have too little or too much magnetic field, and I don't have to keep scraping designs/prototypes because they don't work. You might be able to skip it by doing good internet research with data collected from existing pickups and as provided by manufacturers or something else, but the gauss meter would be my method. That is my own sense though. We don't share a workshop so you have absolutely no obligation to accept it.

I'd expect R&D to be much more laborious than for other kinds of pickups, but ultimately have some kind of good pay off. Stuff like this is on my to-do list. The current market for small magnets has not been properly exploited in the guitar pickup world, IMO.

[David King]

If you are planning to use alnico magnets you need to keep in mind the form factor. Ideally you want a 5:1 height to thickness to avoid self-degaussing. (Some will tell you that a 3:1 ratio is OK but I don't know about that). I think a segmented magnet might give you a more even string to string volume as lang bars tend to have the strongest gauss reading at the ends where the strings are already lower due to the fingerboard radius. With segmented magnets you can stagger the heights according to your needs.

If you use ceramic bars you don't need to worry about degaussing but you will probably want to limit your turns count to 3k or less to keep them from sounding like angry farts.

[Novorca]

If I was embarking on such a thing, I'd start by getting a gauss meter. Using steel blades puts you on a path of a known amount of gauss because you're working with materials and dimensions that have been known to work in guitar pickups already. If I'm going to design a whole pickup around just a magnet, I'd want to be able to make a good judgement of what size magnet I want so I don't have too little or too much magnetic field, and I don't have to keep scraping designs/prototypes because they don't work. You might be able to skip it by doing good internet research with data collected from existing pickups and as provided by manufacturers or something else, but the gauss meter would be my method. That is my own sense though. We don't share a workshop so you have absolutely no obligation to accept it.

I'd expect R&D to be much more laborious than for other kinds of pickups, but ultimately have some kind of good pay off. Stuff like this is on my to-do list. The current market for small magnets has not been properly exploited in the guitar pickup world, IMO.

Thanks for the insight. This is my first pickup building project. I picked a good one seems like no? Okay, we may not share a workshop but we might be able to collaborate. I do have a CNC milling machine and a bunch of years of toolmaking and product development - just not guitar pickups. Anyway - I do have a rough model sketched up and like I always do, I stare at my concepts until the wee hours of the morning. Here's a screen grab of the basic layout. I know there's a lot of detail missing and some things need to be changed. This is iteration #3 and I expect to be at iteration #30 before I actually am cutting any material or ordering supplies. Essentially, I can make anything I need to - so it's not really nessesary for me to be searching for just the right bobbins, base plates or magnet sizes. Although when it comes to magnets, I can do some contour grinding but I don't have a surface grinder to adjust thicknesses - damn.

In this design concept - the magnets here are 2.3" x .5" x .125 (regular humbucker magnets) there's two of them and having looked at this for a while I am thinking that this is too much magnet. I'd like to thin those magnets down to .093 or less to remove some mass. Then I started to think that it might be easier to just use metal blades and stick the magnet underneath like a regular bucker (the easier softer way). I don't want to abandon the "magnet as blade pole pieces" just yet.

Any feedback would of course rock.

[Novorca]

If I was embarking on such a thing, I'd start by getting a gauss meter.

Would this be a good one?

DC Gaussmeter Model GM1-ST

[FunkyKikuchiyo]

Honestly I don't know. I've gotten away without having to have good gauss readings and relied on a very simple homemade test because I haven't done anything so dramatic. I just know that you could over shoot or under shoot the normal range for guitar pickups pretty darn easily if you're not careful.

I also didn't realize you had the machining experience that you do, and was assuming that you'd have to be doing more by hand. If you can quickly fabricate and try a few iterations, then there is less need for a gauss meter - simply try a few different sizes and see what works. My perspective is that there is no way I'd want to make a design when I have no idea what ideal magnet dimensions might be.

[Peter Naglitsch]

Thats the Gauss meter I use. works really good for my needs.

[David King]

You could also sign up for one of Elepro's pc boards and put your own together. Many of us have an Elepro Version II and I've heard no complaints.

I think the standard HB mags are a good place to start. They certainly won't be too strong in this application. You might want to add a steel baseplate or pair of L shapes to aid the mag circuits and add some directional shielding.