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I just finished a pickup winder I have been working on for a few weeks. The winder is a direct driven DC variable speed motor. I am using a digital counter with a reed switch and magnet for counting. The motor has forward and reverse. One very interesting part of this project was the bobbin faceplate and the bracket that holds the magnet on the motor shaft for the counter. Both parts I created in Solid Works and then was able to use a rapid prototyping 3D printer at the local community college to print the parts in plastic. Amazing technology. I "printed" the parts and a few hours later they were done in ABS plastic ready to use and fit perfect. I also cut the control face plate from acrylic using a laser at the same college. This was the first time I have used it a laser and it also is very powerful technology.

Now that this is done...what do I need to know to get started winding?

The cut the face plate and etched the words with a laser cutter engraver.

Solidsworks 3D Face plate (back side)

Actual rapid prototyped face plate printed in ABS plastic

Front of face plate.

Magnet holder for counter. This is mounted on the backside of the motor .


Thanks for looking!

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Brad
Avon, OH

Very cool! You do high quality work! That looks top notch. How many pups have you wound on it thus far?

That's some great manufacturing right there . I've got a very good engineering university very close, as well as a friend who's a cad design specialist. hmmm....

I will be winding my first very soon! Any pointers?

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Brad
Avon, OH

No real pointers per say as I have never done it, but plan on it. However, here is a PRS pickup winding sheet to give you some specs.

Isn't that technology wonderful? I got a nice look at that process working on a Boeing project. When visiting them I got a tour of their rapid prototyping facility in Seattle. They had four "printing" machines of various sizes. I guess the move is on to make a depository process using titanium and other alloys.

Haha....one of the engineers was an RC airplane FANATIC and couldn't wait to show me videos on his pc. I wasn't expecting much more than your typical RC airplane setups but this guy had a $10K jet that was about 4 feet long.....actual jet enigne...oh MAN...what an addict!

Question.....I was was looking online the other day for any kind of counting relay but I couldn't find anything. I wasn't sure what to call a relay that allows you to set a given number of voltage pulses and then kicks a seperate circuit closed after the countdown. If I were to build a winder I'd want to set the exact number of winds and not use a timing relay....giving only an approximate number. Not that you couldn't use a timing relay and get pretty close...I just expected a counting relay would be a common item but it doesn't seem to be.

Is this doable? Any ideas on that? Are you setting a timer on yours or an actual number of winds? If winds.....then tell me how you are doing that.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Counting relay....good idea...I thought a little about this a couple weeks back but never really figured out how to accomplish this. I am guessing that a programmable counter would work with an integrated relay. They make something similar for temperature called a PID temperature controller and I would guess there something similar for counting.

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Brad
Avon, OH

Thanks for posting the chart....very interesting!

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Brad
Avon, OH

No problem! Here is another one I forgot I even had.

Pretty nice machine you have there, congrats. As to advice, I'd suggest working on a tensioning device, which could be as simple as felt held between your fingers or two flat washers. If the washers have a bolt and wingnut to squeeze them, you can adjust drag in the magnet wire. You may also find it helpful to place a dark backdrop behind the winder, allowing you to see where the wire is running. And make a simple hand rest with a guide that functions to limit travel from side to side as you put down layers of wire. Lastly, set up your wire spool down below the winder with a whisker disk to control the unspooling. I use a fishing pole ferrel to guide the wire up from a spool on the floor.

Hope that's clear and helpful.

Dan

this precision is not necessary.....an extra turn of pickup wire is going to be at most, what, 8 inches.....the resistance in ohms on this amount of wire is effectively unmeasurable, and inconsequential when talking about electric guitars. ten (or 50) turns one way or another won't pan out to be a thing, sonically... unless you are talking about cost and big manufacturing, measuring count-by-count, plus or minus 1, is not a viable concern. a single coil pickup has a whole holy hell of a lot of wire on it...

Thanks for the advice. I was planning on a guide "post" but like the idea of adding a hand rest. A tension device and black back drop are both good ideas.

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Brad
Avon, OH

Very nice work!

While counting the exact number of turns is probably overkill... I rarely turn down the opportunity to help someone swat a fly with a sledgehammer. What you're looking for is simply an event counter with at least one relay output. The good news is that these are readily available as kits and off the shelf parts. Any plans to put a servo onto the wire guide in order to achieve exactly the same winding pattern every time?

I was only considering counting an exact number of winds because I assumed that counting relays were just as available as the timing relays that I've used for various projects. In that case there wouldn't any earthly reason NOT to be precise. I recognize that a few winds would make no difference but I thought that since a relay would be necessary one way or the other.....a counting relay would be nuts on accurate. Price will likely sway me toward a timing control....it seems.

....and yeah....if you want to do this reliably you're going to have to control the winding pattern and the feed tension of the spool. The winding pattern can be controlled with a simple cam driven eyelet traversing across the spool surface. This can be designed to allow a quick change of the cam for different spool heights. The math is easy on this. The gauge of the wire divided into the bobbin height will give you the number of turns required to put down one layer of winds. The rpm of the winder at the bobbin will tell you how long it will take....and your cam needs to take that amount of time to traverse the full height of the bobbin in one half of a revolution.

The tension is controlled by adding an adjustable dampner of some sort to the feed spool and then a free floating idler spool between the feed spool and the pickup bobbin. An adjustable dampner can be something as simple as a spring loaded felt or leather pad pushing against a smooth, flat plate....like a clutch. The adjustment needs to be able to apply no pressure.....all the way through to providing enough tension to snap the wire....hence...a spring loaded felt pad with which pressure can be increased by turning a nut. The system is set when enough tension is applied in normal operation to raise the idler pulley and keep it at about the halfway point of it's movement. You don't want a bouncing idler pulley either....or you won't get a compact wind. Tension can be applied to the idler with rubber bands to deal with that but the best course is to make the dampner on the feed spool work as smoothly as possible and use rubber bands on the idler as a sort of "micro" adjustment.

_________________
I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Seems reasonable enough, and considering I've seen counter/relays complete with LED displays for ~$100 that seems far from an absolute show stopper. The reason I asked about using a servo is that it would afford total control of the winding pattern.