Mini Humbucker Number of Winds - Mojo Bobbins

[jrdamien]

Did some searching - am finding nothing satisfactory.

Anyone have info on number of winds for a mini humbucker on Mojo's bobbins? They're both shorter and taller than a normal humbucker bobbin and I'd like some sort of ballpark before I start experimenting.

I'm thinking 6.5/7 in the neck and maybe 7.5 for the bridge.

Again, I know I can use the calculator for a ball park but I wanted to ask of those who may have been winding them.

[big_teee]

If your talking about 42 PE, or 42SPN, that is getting pretty full best I remember with the ones I made.
Probably too much.
Did you try searching the Pickup forum.
I did and it came back with 6 pages of stuff on mini humbuckers.
Also look at the SD site to see what parameters Duncan uses.
I always do that, and come out with some good ideas.
T

[salvarsan]

Are there any real numbers to that winds count, or do you all simply wind to a resistance target?

Also, does anyone have the internal dimensions of a mini humbucker bobbin?
These are the dimensions between the flats.

I would like to include them in the Coil Estimator.

Thanks.

[SonnyW]

Are there any real numbers to that winds count, or do you all simply wind to a resistance target?

Also, does anyone have the internal dimensions of a mini humbucker bobbin?
These are the dimensions between the flats.

I would like to include them in the Coil Estimator.

Thanks.

I have rewound an original Gibson minihumbucker that was the 3x3 variety and I rewound it to 5350 turns per coil, based on weighing the original wire removed. I used 42 PE like the original wire and it came out to 7.82 k ohms. I also have made some with the Mojo bobbins. Here are the dimensions of those. Core Length 2.173" Core Width 0.189" Core Height 0.285" Flange 0.162" per side ( or .514" total width including core dim) By the way, thanks for the coil estimator I use it all the time. I have never been totally clear on how to record the Flange dimension so it would be good to get clear on that.

[salvarsan]

I have rewound an original Gibson minihumbucker that was the 3x3 variety and I rewound it to 5350 turns per coil, based on weighing the original wire removed. I used 42 PE like the original wire and it came out to 7.82 k ohms. I also have made some with the Mojo bobbins. Here are the dimensions of those. Core Length 2.173" Core Width 0.189" Core Height 0.285" Flange 0.162" per side ( or .514" total width including core dim)

Thanks much, Sonny.

By the way, thanks for the coil estimator I use it all the time.

Yer welcome. If there is a feature you want, ask and I'll see what I can do. Bad news: I can't make it save results. Web applications don't work that way.

I have never been totally clear on how to record the Flange dimension so it would be good to get clear on that.

You guessed right on the Flange width, which is the same distance that a guitar string crosses over when the pickup is mounted.

Late edit: The Mini Humbucker is finally in the Coil Estimator rev 07. I'm assuming the whole humbucker measures at 7.82 kOhms or 3910 ohms per coil. It suggests that the wind is tight, in part because I need to model the fill factor either smarter or simpler.

Latest greatest Coil Estimator

[big_teee]

Thanks Salvarsan!
Could you include the P-Bass Bobbins.
Lots of guys ask about turns for them from time to time.
You have the J-bass, but no P?
T

[salvarsan]

You have the J-bass, but no P?T

Gimme some numbers and I'll put 'em in.

[SonnyW]

Thanks much, Sonny.

Yer welcome. If there is a feature you want, ask and I'll see what I can do. Bad news: I can't make it save results. Web applications don't work that way.

You guessed right on the Flange width, which is the same distance that a guitar string crosses over when the pickup is mounted.

Late edit: The Mini Humbucker is finally in the Coil Estimator rev 07. I'm assuming the whole humbucker measures at 7.82 kOhms or 3910 ohms per coil. It suggests that the wind is tight, in part because I need to model the fill factor either smarter or simpler.

Latest greatest Coil Estimator

Yes the ohms reading was for the whole humbucker. I re-wound only one coil because the other original coil could be repaired. Both coils were similar. The one coil that I re-wound was machine wound fairly tight (some spacing between winds in each layer but less than a perfect wind factor), and at 30 grams tension. I can't find my detailed notes on it right now, but I remember trying to make the two coils similar.

[jrdamien]

Based on the size of the mojo bobbins I guessed the number of winds I'd need to wind coils in the 3.5k range with 43 awg. I estimated well!

3700 winds gave me a coil of 3.5k and 3200 winds gave 3.1k.

There was enough room on the bobbin to add at least another 2k winds.

[David King]

Gimme some numbers and I'll put 'em in.

P bass bobbin height is .265-.285" tall. Distance between outermost poles (core length) 1.310". Core width .1875". Bobbin width .998", bobbin length, 2.110".

[big_teee]

P bass bobbin height is .265-.285" tall. Distance between outermost poles (core length) 1.310". Core width .1875". Bobbin width .998", bobbin length, 2.110".

I sent him a PM Yesterday, but mine is with the taller bobbins that fit to the bottom of the mojo covers.
Stewmac instructions say to make winding area 11/32", which is .34375, I use .340"
1.315x.1875x.340x.975"
That was mojo pickup flatwork I built up.
Used .630" magnets, same as in the Stewmac kit.
T

[salvarsan]

Guys, using Big_Teee's P-Bass dimensions and a coil resistance of 5.250 kOhms (= 10.5 k for a pair), the winds estimate is near 10,000 winds of awg42. Is this even in the right ball park?

[David King]

I had a 70's P pickup in here earlier today but I didn't think to measure it. My measurements come off a very old Jackson pickup that had very short magnets (.460 long) It might be a little longer and wider than the typical. My shells are a bit on the small side. Mojo's are probably close.

Yes 10,000 turns is right on the money. Is that what we were trying to figure out?

[big_teee]

Guys, using Big_Teee's P-Bass dimensions and a coil resistance of 5.250 kOhms (= 10.5 k for a pair), the winds estimate is near 10,000 winds of awg42. Is this even in the right ball park?

Sounds good to me.
Thanks again for the efforts!
T

[fieldwrangler]

I've had quite a history of piling various amounts of winds onto these Chinese mini bucker bobbins that I use quite often; rarely am I after anything "vintage," though.

If necessary I'll check out the precise dimensions of these and report back some specifics (I tend to use a lotta 43 myself.)

Bob Palmieri