Making mini-rail hambucker, wire gauge, number of turns?

[Valkyrience]

Hi. I am new to this site. I apologize in advance for my English, is not my native language. 

I'm going to make mini-rail hambucker, for electric ukulele. I have shortened bobbins, magnet and rails from old mini-rail hambucker. And now I have some questions about wire. What gauge of wire do I need? Can I use 44 or 42 awg or should it be thinner? And how many turns do I need on each bobbins (magnet -ceramic)?

Thank you in advance for your answers. 

 

[Bizman62]

Hi and welcome!

I'm surprised that the more electronically savvy haven't chimed in. Hopefully my post punts your question up to the top again...

For what I know about pickups, both gauges you mentioned are commonly used in guitar industry. 5000 wounds seems to be a good starting point. For what I could find there's no major differences in pickups for various instruments, mainly it's just the amount of pole pieces. And after all the tuning of a ukulele is similar to a guitar played on the fifth fret on the three highest strings! That's exactly the same frequencies so any guitar pickup winding instructions are fully valid.

Here's some reading: https://del-tone.com/lets-talk-about-pickups-1/

And here's some easy viewing: https://youtu.be/ey9pHFl7HuM

There's lots more to experiment with as there's no recipe for a "good" pickup. You can change to a different gauge in the middle of your winding for some unique tones, you can use weaker or stronger magnets, ceramic/AlNiCo/neodymium...

Also remember that for magnetic pickups you'll have to use steel strings! For a nylon stringed uke you'd need a piezo pickup.

 

 

[Valkyrience]

9 hours ago, Bizman62 said:

Hi and welcome!

I'm surprised that the more electronically savvy haven't chimed in. Hopefully my post punts your question up to the top again...

For what I know about pickups, both gauges you mentioned are commonly used in guitar industry. 5000 wounds seems to be a good starting point. For what I could find there's no major differences in pickups for various instruments, mainly it's just the amount of pole pieces. And after all the tuning of a ukulele is similar to a guitar played on the fifth fret on the three highest strings! That's exactly the same frequencies so any guitar pickup winding instructions are fully valid.

Here's some reading: https://del-tone.com/lets-talk-about-pickups-1/

And here's some easy viewing: https://youtu.be/ey9pHFl7HuM

There's lots more to experiment with as there's no recipe for a "good" pickup. You can change to a different gauge in the middle of your winding for some unique tones, you can use weaker or stronger magnets, ceramic/AlNiCo/neodymium...

Also remember that for magnetic pickups you'll have to use steel strings! For a nylon stringed uke you'd need a piezo pickup.

 

 

Hi. Thanks. My uke has steel strings and handmade hardtail bridge. I asked about gauge and number of turns, because I'm going to made mini-rail pickup, it has smaller bobbins and I doubt that 5000 turns of 44-42 awg can fit in such small bobbin.

[Bizman62]

Fewer windings only make the pickup a little weaker, or less hot. As it's described in the video I linked you can use thinner wire to fit more windings if needed.

[curtisa]

2 hours ago, Valkyrience said:

I asked about gauge and number of turns, because I'm going to made mini-rail pickup, it has smaller bobbins and I doubt that 5000 turns of 44-42 awg can fit in such small bobbin.

Use a pickup winding calculator to estimate how much wire you'll fit on the bobbin:

http://www.jdguitarworks.com/coil/coil.html

Note that the calculator is written assuming you want to target a specific resistance. You have to work backwards a little bit and adjust the resistance and bobbin specs until the resultant number of turns provided by the calculator becomes <= 5000.

Pick a bobbin style ('Strat 1967' is a good start, you'll tweak the stock values in a second), AWG size and insulation build thickness. Leave the resistance value as-is. In the 'Bobbin Core Dimensions' table adjust the presented measurements to match the bobbin you want to use. Note that the presented names of the dimensions are a bit vague, but should correspond with the following measurements of your bobbin:

Hit the 'Calculate' button and have a look at the 'max winds' entry on the table, which tells you how many turns you can fit on the bobbin given the dimensions and wire gauge you selected. Pick the result in the column based on how good you think you can do your winding, from 'Loose Scatter' to 'Tight Machine'. Ignore the 'Perfect' column.

You can also refine the results further by tweaking the resistance to work out exactly the pickup winding specs you'll end up with. If, after you press the 'Calculate' button you see  any of the presented values are red, they are indicating that the resistance you entered, using the bobbin/wire parameters you selected, will not fit in the bobbin. Reduce the resistance and try again. Try also switching between AWG42 and AWG44. Don't select anything finer than AWG44, as the wire is hard to get and impossible to work with.

As an example, if I use the 'Strat 1967' option, AWG44, insulation build = single, resistance = 7100, leave the bobbin dimensions as-is and only change the length to 1.7" (I don't know if this is a realistic value for a uke pickup bobbin?) I get the following results. None of the values are red which suggests the pickup is achievable even if hand-wound with a fair degree of slop:

 

[Valkyrience]

25 minutes ago, curtisa said:

Use a pickup winding calculator to estimate how much wire you'll fit on the bobbin:

http://www.jdguitarworks.com/coil/coil.html

Note that the calculator is written assuming you want to target a specific resistance. You have to work backwards a little bit and adjust the resistance and bobbin specs until the resultant number of turns provided by the calculator becomes <= 5000.

Pick a bobbin style ('Strat 1967' is a good start, you'll tweak the stock values in a second), AWG size and insulation build thickness. Leave the resistance value as-is. In the 'Bobbin Core Dimensions' table adjust the presented measurements to match the bobbin you want to use. Note that the presented names of the dimensions are a bit vague, but should correspond with the following measurements of your bobbin:

Hit the 'Calculate' button and have a look at the 'max winds' entry on the table, which tells you how many turns you can fit on the bobbin given the dimensions and wire gauge you selected. Pick the result in the column based on how good you think you can do your winding, from 'Loose Scatter' to 'Tight Machine'. Ignore the 'Perfect' column.

You can also refine the results further by tweaking the resistance to work out exactly the pickup winding specs you'll end up with. If, after you press the 'Calculate' button you see  any of the presented values are red, they are indicating that the resistance you entered, using the bobbin/wire parameters you selected, will not fit in the bobbin. Reduce the resistance and try again. Try also switching between AWG42 and AWG44. Don't select anything finer than AWG44, as the wire is hard to get and impossible to work with.

As an example, if I use the 'Strat 1967' option, AWG44, insulation build = single, resistance = 7100, leave the bobbin dimensions as-is and only change the length to 1.7" (I don't know if this is a realistic value for a uke pickup bobbin?) I get the following results. None of the values are red which suggests the pickup is achievable even if hand-wound with a fair degree of slop:

 

Using this calculator with my bobbin parameters I got only 3,75 kOm on tight scatter with awg 44. Is it enough? It will be hambucker, I think I can double this resistance (3.75x2 =7.5), isn't it? Is it enough?

[curtisa]

1 hour ago, Valkyrience said:

(3.75x2 =7.5), isn't it?

Correct - two coils in series for the whole humbucker would yield 7.5k. If you can tighten up the winding pattern you might be able to achieve some of the values quoted in the 'machine' winds and therefore get more output.

With 3.75k per coil it will work, but it will be a bit on the weak side. Only real way to find out is to build it and see how it sounds.

[Bizman62]

9 hours ago, curtisa said:

Only real way to find out is to build it and see how it sounds.

A lot depends on your goal: Are you after a Heavy Metal screamer or a mellow clean sounding instrument.