First Pickup; question

[jwendt2003]

I just wound my first pickup; strat, alnico 2, 42awg poly, 7/16" space for coil. After miss calculating the turns, I finally ended up a little overwound with 7k ohms. I'm not sure how many turns it is, but it doesn't look like the coil is going to fit within the cover. Either it's too loose, or something. I did keep pressure on the wire while it was winding. Any advise? Thanks, Jim

[Magnut]

You could unwind a bit while checking the ohms as you go. Just put something through the middle of the bobbin and carefully pull off some layers.

What resistance were you shooting for?

[jwendt2003]

I was trying to go for 8000 turns, but I was way off on my counter because it's a bike counter. I had calculated with a 26" wheel, 81" circumference, 10.2 miles would equal about 8000 turns. At that point, I only had 2.7k ohms, so I aimed for a little past 20 miles on the 'counter'. I was trying for 6.25 - 6.75k range. I'll try to unwind some, but I wonder if it will be enough to make it fit. Are you supposed to use rubber bands to keep the coil snug when you pot?

[Mark Hammer]

If it's that bulky, then there was an issue with wire tension. Admittedly, for the novice, it is both hard to gauge what "appropriate" wire tension is, and anxiety provoking to want to add a little more tension and risk tearing the coil and having to do yet another splice.

Although the optimum is to have the wire snug enough that there is very little play, you can compensate to some extent by packing the wire together post-wind. What I do is use teflon plumber's tape, the very same kind you can buy for under a buck a roll. It conforms to the coil, but you can pull it tight so that it packs down the coil, without necessarily tugging on the coil itself and risking a tear. It's also very thin, so you can wrap a half dozen or more layers over top of the coil before you really start to notice it building up, and adhesive free, so you can unwind it and start over again. I'm sure you'll get the next wind right, but for now, try packing the coil in with teflon tape. It's like "spanx" for pickups! (Spanx - Wikipedia, the free encyclopedia)

[RedHouse]

I was trying to go for 8000 turns, but I was way off on my counter because it's a bike counter. I had calculated with a 26" wheel, 81" circumference, 10.2 miles would equal about 8000 turns. At that point, I only had 2.7k ohms, so I aimed for a little past 20 miles on the 'counter'. I was trying for 6.25 - 6.75k range. I'll try to unwind some, but I wonder if it will be enough to make it fit. Are you supposed to use rubber bands to keep the coil snug when you pot?

Your first order of business is to get a turns-counter going on your mnachine, best is either Opto (recommended) or Hall Effect (way more trouble) or mechanical (way less accurate).

I just wound my first pickup; strat, alnico 2, 42awg poly, 7/16" space for coil. After miss calculating the turns, I finally ended up a little overwound with 7k ohms. I'm not sure how many turns it is, but it doesn't look like the coil is going to fit within the cover. Either it's too loose, or something. I did keep pressure on the wire while it was winding. Any advise? Thanks, Jim

Wind to a turns count rather than resistance. Resistance varies with temp, friction, tension, speed, room temp after winding etc.

Find a turns-count that gives you the resistance ballpark you are aiming for, then go from there.

Later, when you can measure your inductance or plot the curve (even better) you will be able to chart your progress.

Loose can give character, and funk, but also microphonics, so you will have a trade-off there. Potting can help microphonics but pretty much cancels out the loose thing. Experimentation is your friend, take notes, be dilligent, and skeptical.
(did I mention taking notes?)

Pickup winding much like wine-making or cooking is the artful combination of things and techniques that build up in a systemic way to give an overall effect, isolate them out and you have nothing but an ingredients list and a technical buildup of patterns and materials.

[David Schwab]

What I do is use teflon plumber's tape...

You know, I always mean to try that, it would be easier than with sticky tape.

[mkat]

You know, I always mean to try that, it would be easier than with sticky tape.

Yep, teflon works great, it's cheap and it can be easily removed if needed. I use it on full unpotted strat coils where I didn't want to take the risk of damaging the outer windings.

[Possum]

....

7K is about the limit for a strat bobbin, it might make a good sounding bridge pickup. Drop it down to 6.5-6.8K and see if it'll fit under the cover. You can always wrap the coil in tape if it looks like its going to get cut by the cover, I used to do that all the time on some strat pickups I did that were 7K. Just plain old scotch tape or as mentioned teflon works fine. Guitar Jones has some black scotch type tape thats made for just that, but who knows where he is? Ballpark values for average strat pickups are 6.5K or a little hotter for bridge, 6.2 or for middle, and 5.9K neck.

A good way to get turn counts, is first get a better counter so you don't have to pedal all those miles My winder has a mechanical counter thats built like a tank but its a pro winder, you can look on Mcmaster Carr website for electrical and mechanical counters, takes some figuring out. Anyway, when I'm working with new pickups I've not wound before I'll wind a certain number of turns in a ball park guess then, scrape the wire and take a reading and write the ohms down for those numbers of turns. If its not hot enough, seal the scrape with some lacquer or shellac on a Q tip, then wind more on etc. etc. If you over shoot, no problem, set your counter to zero or note what the count is if it'll count backwards, and unwind 50 or 100 turns at a time and take a reading and write it down. Keep records on counts and ohm readings. On your next batch of wire all this might change, the wire might be thicker or thinner and your resistance per foot will change. Its not such a big deal really and best to just wind to your normal turn counts even if the DC resistance changes. Good idea to buy a serious micrometer to meausre wire with if you intend to stay in the hobby of self mutilating tone torture :-)

[jwendt2003]

The teflon tape worked great! My 2nd pickup was much nicer. Everything fit. I unwound the 1st one to 6.7k, and the second one is at 6.3k. I think the 1st one was just wound loose...I'll load them tomorrow and try them unpotted first. -Jim

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[David Schwab]

In the beginning it's hard to wind a neat coil. And stop breaking wire. But it gets better... eventually.

I agree with Possum on the pickup values... I find 5.6K makes a really nice sounding neck pickup. Save the higher winds for the bridge.

[ShannonH]

here here....

I find 5.6K makes a really nice sounding neck pickup. Save the higher winds for the bridge.

Especially with A2. 7k single with A2 is a recipe for tone suck....

[RedHouse]

...A2 is a recipe for tone suck....

I disagree with that

[ShannonH]

please elucidate.....

[David Schwab]

I disagree with that

You left out a part:

7k single with A2

A 7K neck pickup would need more oomph than with an A2. Unless you like a dark tone. But a 5.6K with A2 would sound great.

[ShannonH]

You left out a part:



A 7K neck pickup would need more oomph than with an A2. Unless you like a dark tone. But a 5.6K with A2 would sound great.

Which is how I look at it. My experiments with hot wound A2 in a single coil was not very pleasing to my ears, but everyone's mileage may vary. I think that the lower wind sweetens the natural propensity of the A2. Excellent Jazz tone.
Peace