Coil calculating software and bobbin winding information

[the great waldo]

Hi All
In my recent search for the specs for a broken Duncan distortion pup I came across a coil winding calculator with a 50mm humbucker in one of the template boxes. It seemed pretty good but I lost the link. Would it be a good idea to put any such software into the faq section? also would it not be a good idea to have a comprehensive coil/bobbin specification list somewhere as a reference for anyone wishing repair bobbins from commercially made pickups. I found it was quite long winded looking for information on a Duncan distortion that I had to rewind (I took more time to research than to do the repair!) Looking forward to members opinions on this.

Cheers

Andrew

[David Schwab]

Coil Estimator

Designed by our very own Salvarsan.

[salvarsan]

I took more time to research than to do the repair!

Spending more time on research means you want to get it done correctly.

The coil estimations are for a single bobbin.
Save a copy of the estimator on your workstation.

Since a Duncan Distortion specs at 12,700 or 16,600 ohms for two coils,
you want to estimate for only one at 6,350 or 8,800 ohms, respectively.

I get plausible estimates for both using #43 single or #44 double build.

[David Schwab]

I did a rewind on a '76 Gibson Thunderbird pickup the other day. Here's a few tricks. When I got the pickup it had been removed from the epoxy, and both coils were quite a mess. So forget trying to get a reading from it. I was told the neck pickup read 6.5K, and I have other notes stating the same thing. At the same time there was another version of this pickup that seems to have been wound with 44AWG, and read 21.4K.

The first thing I did was weigh the full bobbins. Each one weighed 12 G. I looked at the wire under a loupe, and it matched my 43AWG. So I wound a coil until I was around 12 G in weight. My scale is not all that accurate with very light things, but it got me in the ballpark. (I probably could have added a larger weight and then zeroed it out, but I hadn't thought of that at the time)

I measured the DC resistance and was over. Now here's a trick I figured out. I had wound 3600 turns, and the coil read 4.30K. It should have been 3.25K. So take 3600 and divide it by 4300. The result is 0.837. Then I multiplied 3250 by 0.837 and got 2720. I wound the next coil 2720 turns and it came out 3.25K. Then I just unwrapped some wire from the other coil until they matched.

So that's what I use when I want to get to a certain resistance when I know how many turns I have done.

[J M Fahey]

The first thing I did was weigh the full bobbins. Each one weighed 12 G. I looked at the wire under a loupe, and it matched my 43AWG. So I wound a coil until I was around 12 G in weight

Now here's a trick I figured out. I had wound 3600 turns, and the coil read 4.30K. It should have been 3.25K. So take 3600 and divide it by 4300. The result is 0.837. Then I multiplied 3250 by 0.837 and got 2720. I wound the next coil 2720 turns and it came out 3.25K.

Hey, that's smart.
No, I'm not kidding, I mean it.
I love minimalistic, yet practical solutions.

[the great waldo]

That was the one, thanks David.

Cheers

Andrew

Coil Estimator

Designed by our very own Salvarsan.