Bigsby pickup magnet orientation/layout?

Dan Otranto · From: Vermont, USA

Hello,
New member here.
I am in the process of making a Bigbsy guitar in the style of the "Hezzy Hall" model and I'm currently trying to find out how the magnets in the pickups were arranged.
I've seen some gut shots of the 'rail' type that have the cast iron base plate and bobbin rail but I've never seen how the magnet, or magnets were arranged within either type of bigsby pickup- either the rail type or the 6 pole piece made of black oxide hex screws. The pickups I'm making right now are the ones with the screw pole pieces (although I plan on making some of the rail ones in the future).

Anyone know how the magnets were arranged in these? My best guess is that they are P90 style construction with two flat magnets placed above or below the coil but I've seen comments before in my digging for info that this was not the case although I've not found any further information.
I've wound a test P90 style constuction with 5500 winds of 38 gauge wire (most common spec I've seen) but this only gave me a resistance of 1.6k which is just too low...I was hardly getting any sound out of it with the pickup extremely close to some strings. I'm aiming for 3.4k to 3.6k....gonna try to get about 6500 winds of 40 gauge on these to see where that gets me. (There's no reason why I put the magnets on top in this test, I was just curious as to what that would be like).

Chris Lucker · From: Los Angeles, California USA

I have never seen a Bigsby pickup that had its magnets mounted your way. In fact, the p-90 style "Bigsby" pickups are what Gretsch made for their reissue Bigsby guitars made in Japan -- what, about fifteen or twenty years ago? The pickups they used were like p-90s and nothing like a Bigbsy.

A Bigsby pickup has a heavy iron core that is a blade, or a foundation for the cap screw poles. Your ohm reading is fine, but you have no iron in your pickup other than your screws. And your magnets are small.

BIG Iron core. Big magnets mounted vertically on the OUTSIDE of the coil. I have posted numerous photos of Bigsby pickups here before. At the Pickup Winders page too. Do a search.

Here is what a Bigsby pickup looks like -- the TOP photo. You are making a pickup like the fake Bigsby I am showing at the bottom -- ALERT BOTTOM TWO PHOTOs NOT REAL BIGSBY. IT IS A GRETSCH PICKUP From the Bigsby reissue guitars they made in limited numbers. (My edit was to clarify that the bottom two photos are Gretsch imitation Bigsby pickups — not Gretsch guitar pickups)

_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

Dan Otranto · From: Vermont, USA

Thank you so much for those photos, it clears up a lot!
Do you know if the hex screw pole piece pickups Bigsby made had the same magnet arrangement? I'm having a hard time envisioning 5000-5500 winds on 38 AWG wire fitting in a bobbin spool that skinny, this bobbin has 5500 and it is pretty much filled up....maybe I got the dimensions very wrong, or

The internal dimensions of the pickup covers I designed is 2.885" x 1.325" x .700"

Here are the pickups

here is the guitar so far

Chris Lucker · From: Los Angeles, California USA

Where did you get the concept of 5500 winds? Just curious. The win numbers written into Bigsby’s pickup winding base board are not what he wound. For example, you could never fit the number of winds noted for the ten string pickups. The cover can’t fit. Also, he would pickups according to the tuning ordered for each steel guitar neck. And I know the original Hezzy guitar pickups have a difference of 662 winds between neck and bridge.
Since your construction is so different, experiment and see what sounds best to you. It may likely be better than a Bigsby pickup.
Good for you making your own! And, great looking pickguards.
_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

Dan Otranto · From: Vermont, USA

I had contacted an owner of some of his steels and he had his pickups rewound, those were the specs I got from him. I'm just going through his writings and he says that the pickups for the steels had around 2k and the guitar had a bit shy of 4k.

I redesigned the bobbin so I can fit the magnets on the side, and stuck some larger ones in there to boot. Dealing with magnets is a bit tricky, I've found it difficult to find sources for them where they have a good selection of dimensions, and machining them is off limits sans wire EDM. Grinding/abrasive cutting can introduce too much heat and make them go wacky.

Chris Lucker · From: Los Angeles, California USA

Steel pickups a little under 2k.
Is that bottom plate aluminum or steel? You want a big ferrous bottom.
On steel pickups you get a good reading all the way out to the mounting screws. A very wide field.
_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

Dan Otranto · From: Vermont, USA

The backing plate is low carbon steel, 0.072" thick. I could go up to about 0.100" thick steel.

Chris Lucker · From: Los Angeles, California USA

I am not criticizing, but you are not going to gate a bigsby style pickup with your approach. You need lots of iron, which you are not going to achieve with your light back plate and it does not look like your screws are threaded into your ferrous base. And, although you have your magnets set correctly now, you are still winding your coil over a nylon or plastic bobbin that is farther from the slugs to cap screws. Bigsby used bobbins made of material that is like vintage file folder material. I make mine in-place, although I am sure Bigsby, or his daughter, made them on a jig.

I bet you saw a picture of the Fake Bigsby pickups made in Japan for Gretsch's reissue Bigsby Spanish guitar project and are copying those. And, as you said at the beginning, those are just P-90s and not like a Bigsby pickup in construction. Your parts look like the parts in the two fake Bigsby pickup photos I provided above.

Good for you making your own pickups. I bet yours will come out great and even better than Bigsby pickups. I think Wright's did.
_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

Mark Perrodin · From: Tucson Arizona, USA

that is one sexy guitar. the vibrato looks great. are you cnc’ing them? outstanding!

Dan Otranto · From: Vermont, USA

Hey, thanks!

pickups are CNCed
Bridge, tremolo parts are cast

I finished this one here are some pics

Currently working on a Bigsby-fied old Kay Swingmaster and building a Bigsby inspired baritone console.
https://www.instagram.com/__repoman__/

My castings have been getting poorer and poorer recently though...I just got an old cast aluminum car wheel to cut up and use that for casting stock. Supposedly it makes better castings than 6061 or 5052 extrusion (which is what I've been using/machining scraps). I think my casting sand (Petrobond) is getting long in the tooth too.

Chris Lucker · From: Los Angeles, California USA

Call SoCal Speedshop or your local hot rod/motorcycle parts shop and ask what alloy to use.
_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

Bill Hatcher · From: Atlanta Ga. USA

Did bigsby use those dakware knobs?

Dan Otranto · From: Vermont, USA

Yes, although I think the ones I have a slightly larger than the ones used on the Grady Martin and Hezzy Hall guitars. Bigsby seemed to use different knobs on almost every one of his builds.

Chris Lucker · From: Los Angeles, California USA

He also machined some of his switch knobs, especially the push button tips. His pot knobs were sometimes cast as well, using this knob as the pattern —without the long stem.

_________________
Chris Lucker
Red Bellies, Bigsbys and a lot of other guitars.

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