What kinds of coil-winding tensioner do people use, or avoid?

[Joe Gwinn]

I've been thinking about what technical properties and designs are required of a tensioner for it to work for winding pickup coils, which are far from round, and I'm curious to know what makes and models of tensioner are known to work or (more to the point) not to work for winding pickup coils.

Lots of people use spring-loaded wool felt and/or their fingers. This works well until production volume grows, and the fingers wear out.

I recall Possum trying an Azotic tensioner, which failed miserably, and was returned to the maker. (I think Possum became despondent and reverted to felt.)

I also recall that there were tensioners on the old mechanical Leesona winders used by Fender in the 50s and 60s, so I assume that these tensioners did work.

Anyway, I'm fishing for ideas and experiences.

[ken]

Joe,

I still use fingers for most things, which also really helps when I go ultralight fishing. Four pound test fishing line feels like a garden hose next to 43 gauge wire.

On my Stevens winder, I'm still using the weirdo tensioners I got when I bought it. Here is an example.

The only problem was trying to find spare parts - there aren't any. Also, the tensioner has to be kept obsessively spotlessly clean with no lube anywhere
or it will break the wire. However, it works great as long as you don't wind too fast... or the wire wasn't put on the spool too tight or too loose...
or the electric brake was maladjusted... or the moon was full...

ken

[Steve Conner]

I only have experience winding the ordinary sorts of coils used in electronics, which are made roundish for easy winding. It's a mystery to me how anyone can wind pickup coils at high speed at all, let alone control the scatter consistently.

[Tom Phillips]

It's a mystery to me how anyone can wind pickup coils at high speed at all, let alone control the scatter consistently.

+1 to that. On a related note I recently ran across an interesting video interview with Abigail Ybarra. She has been winding pickups at Fender since 1956. The video is available at The Queen of Tone.. (Abigail Ybarra) - YouTube
Tom

[madialex]

+1 to that. On a related note I recently ran across an interesting video interview with Abigail Ybarra. She has been winding pickups at Fender since 1956. The video is available at The Queen of Tone.. (Abigail Ybarra) - YouTube
Tom

notice there are no limiters.

[Joe Gwinn]

I only have experience winding the ordinary sorts of coils used in electronics, which are made roundish for easy winding. It's a mystery to me how anyone can wind pickup coils at high speed at all, let alone control the scatter consistently.

It's amazing what one can learn to control by hand. Think of a golf swing. The club head is moving far too fast for thinking, and yet if you close your eyes you'll miss, so the eyes are somehow in the control loop. But it takes lots of practice for this to work.

I saw a guitarist in a concert a few months ago. Don't recall the artist's name, but he had very long thin fingers (spider fingers) and in a riff his fingers literally disappeared into a blur. The hand is truly quicker than the eye. Again, one cannot think that fast, and lots of practice is required. Nor was he looking at his fingers as he played.

[Joe Gwinn]

On my Stevens winder, I'm still using the weirdo tensioners I got when I bought it. Here is an example.

Who is it made by? Are there any markings? The photos isn't quite clear enough to tell how it works, although I think i see a brake shoe and lever arm.

The only problem was trying to find spare parts - there aren't any.

The manufacturer is long gone, maybe even the name is gone.

Also, the tensioner has to be kept obsessively spotlessly clean with no lube anywhere
or it will break the wire. However, it works great as long as you don't wind too fast... or the wire wasn't put on the spool too tight or too loose...
or the electric brake was maladjusted... or the moon was full...

As for the no-lube requirement and fussiness about the feed spool, the tensioner may be missing its pre-tensioner.

How fast can you wind, in rpm?

What usually breaks? Hmm. Do you have a broken tensioner I can borrow? If I can (given the capabilities of the machine tools in my shop), I'll make new parts and repair the unit. Not to mention measure its every detail.

[SonnyW]

On my machine winder, I use two sets of felt tensioners, plus the Azonic whisker disks. I have different sizes for different spools of wire. The wire comes off the spool vertically and the whisker disk slows it down enough to eliminate tangles, then it goes through a guide and then through the first felt tensioner which I keep fairly loose. The second felt tensioner is in line with the first one about three inches away and it is the one that I adjust the tension with. Both of them are just a couple of pieces of 1/4 inch felt about 1 inch by two inches, the top felt is glued to an aluminum plate and tensioned with two thumb screws. The spool is stationary but the guide and both felt tensioners move with the traverse. I use a Jonard spring gauge to adjust the tension to whatever grams I need. It works for me.



The four contraptions on the rod I am not sure of the function of, I think they might be tensioners for larger wire. The three rollers to the side are part of a taping attachment that I don't use, but in either case I didn't take them off.

[ken]

Here is the back of the unit, 'upside down' so you can see manufacturer's markings and also right side up with the adjusting knob at the top.
You can click on the photos to make them bigger.

I did some research, and found out this is part of a 'gang tensioner' used with a winder that can wind many small coils at once. Think little bitty TV or radio tuner oscillator coils. The winder has a long arbor (mandrel) and the coil forms all mount on it in a long row like shish kebab does on its stick when you're barbecuing. I made a long arbor for it so I can use the machine to wind humbucker coils the same way - four at a time.

This unit is bolted to a rod through the hole in its middle, and the rod is then mounted in a rack with a spool of wire dedicated to it. Each tensioner would be set up to deal with a specific gauge of wire. Want to change wire gauges? Use a different tensioner.

I have a few tools too , but luckily I didn't have to replace much. I only replaced a couple of springs and some felt brake pads.

My main issue was using the unit with a five pound spool, the wire coming off the spool was whipping around too much and getting caught where the wire enters the unit. I went to a sporting goods store and bought the biggest ultralight fishing spinning rod line guides I could find and some 3/32" brass music wire to make a wire guide. I used a carboloy? guide so the guide wouldn't ever wear out or catch and break the wire. This way the wire feeds much neater off the spool and doesn't get caught going into the tensioner.

The tensioner is very simple really... the big black wheel has the wire going around it and rotates, the lever arm is very short so it isn't very sensitive (this can be a help with very fine wire) and the tires on the wheels are just rubber O rings. This thing was designed to basically last forever. I wound a round coil using 44 gauge wire to test it, and if it's set up juuuust right will wind Tele rhythm pickup bobbins with 43PE all day.





ken

[Joe Gwinn]

Here is the back of the unit, 'upside down' so you can see manufacturer's markings and also right side up with the adjusting knob at the top.
You can click on the photos to make them bigger.

The attachments came up as invalid links, so something didn't work.

A few edge-on photos would also help.

I did some research, and found out this is part of a 'gang tensioner' used with a winder that can wind many small coils at once. Think little bitty TV or radio tuner oscillator coils. The winder has a long arbor (mandrel) and the coil forms all mount on it in a long row like shish kebab does on its stick when you're barbecuing. I made a long arbor for it so I can use the machine to wind humbucker coils the same way - four at a time.

This unit is bolted to a rod through the hole in its middle, and the rod is then mounted in a rack with a spool of wire dedicated to it. Each tensioner would be set up to deal with a specific gauge of wire. Want to change wire gauges? Use a different tensioner.

The tensioner cannot be adjusted? What wire guage and tension are these units made to provide?

I have a few tools too , but luckily I didn't have to replace much. I only replaced a couple of springs and some felt brake pads.

My tools weigh more than your tools? I have a lathe and a vertical mill, so I could make just about everything I see in the picture. But no need for springs and felt pads. I thought something major was broken. But one can wind music-wire springs on a lathe. Or make a winding jig.

My main issue was using the unit with a five pound spool, the wire coming off the spool was whipping around too much and getting caught where the wire enters the unit.

Sounds like a whisker disk would be helpful.

I went to a sporting goods store and bought the biggest ultralight fishing spinning rod line guides I could find and some 3/32" brass music wire to make a wire guide. I used a carboloy? guide so the guide wouldn't ever wear out or catch and break the wire. This way the wire feeds much neater off the spool and doesn't get caught going into the tensioner.

That works, and I've seen exactly that approach on textile machinery. I think. I'm not really visualizing this part.

The tensioner is very simple really... the big black wheel has the wire going around it and rotates, the lever arm is very short so it isn't very sensitive (this can be a help with very fine wire) and the tires on the wheels are just rubber O rings. This thing was designed to basically last forever.

What is the diameter of the big wheel? That will give me the scale. The parts seem to be injection-molded of a black plastic of some kind, and so should be fairly light. Can you tell what it's made of?

What is the lever arm made of? How thick is it?

The issue with the short arm and fine wire is not the sensitivity per se, it's the inertia of the mechanism, chiefly the arm and the roller at the end, which appears to be made of brass. When winding oblong bobbins such as for a pickup, the wire speed varies cyclically with two pulses per rotation. If the tensioner mechanism inertia is too high the force required to abruptly accelerate the parts of the mechanism exceeds the strength of the wire, which breaks. Even if it doesn't break, the insulating film may be disrupted, causing increased propensity to short between turns.

This, plus mechanical resonance I suspect, is what did the Azonic tensioner in when Possum tried it.

I wound a round coil using 44 gauge wire to test it, and if it's set up juuuust right will wind Tele rhythm pickup bobbins with 43PE all day.

How many turns in how many minutes? I'm trying to estimate the max rpm the tensioner can handle. This plus the inertia governs the stress on the wire, and the pulses per second sets the resonance limit.

[SonnyW]

+1 to that. On a related note I recently ran across an interesting video interview with Abigail Ybarra. She has been winding pickups at Fender since 1956. The video is available at The Queen of Tone.. (Abigail Ybarra) - YouTube
Tom

Thanks Tom for posting that video link. I hadn't seen it before. Notice the bright light from above and the white card behind the bobbin, so she can see the shape of the coil as it fills, and also how she steadies her hand on the table. Also I think it matters about the distance from her fingers up to the bobbin. These are all the same things that I have ended up doing before I saw this and I think all of them help controlling scatter and coil shape while winding. I was also watching the counter and she wasn't winding what I would call terribly fast. I was impressed that she could keep her concentration and do the interview, but then again she started winding when I was 8 years old. I have unwound several of her pickups and her winding is very consistently done.

[ken]

I'm going to try to answer all Joe's questions. I have already reposted the broken photo links, just click on them to make them bigger.

I think the tensioner was designed for winding 28 gauge or smaller TV coils, many thousands of them of one kind before resetting. The knob at the top of the tensioner with the spring and the brake shoe mounting screws are the only real adjusters.

The black plastic ring is 3" diameter and 1/4" thick. It does seem to be injection molded or even turned on a lathe since all the corners are sharp. It isn't made of styrene or butyrate, after all these years it is still perfectly flat and hasn't warped or deformed. It's a dense plastic, it's relatively heavy.

The Geo. Stevens winder runs at an average speed of 300 RPM at the mainshaft for round coils, I have my winder at 1/3 full speed or a little more to do humbucker coils.

My problem was that the tensioner is only about 16" above the top of a five pound spool of wire, so when the wire comes off the top of the spool it still is in relatively big loops. I use the guide to neck the wire down before it enters the tensioner so it doesn't get caught where the wire enters the tensioner.
I have the winder in storage right now, so I'll have to go there to take another photo.

ken

[Joe Gwinn]

I'm going to try to answer all Joe's questions. I have already reposted the broken photo links, just click on them to make them bigger.

They work; thanks.

I think the tensioner was designed for winding 28 gauge or smaller TV coils, many thousands of them of one kind before resetting. The knob at the top of the tensioner with the spring and the brake shoe mounting screws are the only real adjusters.

From 28 AWG (0.0137" dia single build) to 43 AWG (0.0025" dia) is a big jump, 5.5 to 1, and yet it can be teased into working.

What do the adjustments change?

The black plastic ring is 3" diameter and 1/4" thick. It does seem to be injection molded or even turned on a lathe since all the corners are sharp. It isn't made of styrene or butyrate, after all these years it is still perfectly flat and hasn't warped or deformed. It's a dense plastic, it's relatively heavy.

I'd guess Bakelite, given the age and your description. And Bakelite easily does sharp edges. Modern winders seem to use nylon or delrin.

You mentioned that the tire in the pulley was some rubber O-rings. I'm guessing that it is a pair of rings side-by-side in a tight-fitting rectangular groove.

The Geo. Stevens winder runs at an average speed of 300 RPM at the mainshaft for round coils, I have my winder at 1/3 full speed or a little more to do humbucker coils.

So, you are winding pickups at 100 rpm?

My problem was that the tensioner is only about 16" above the top of a five pound spool of wire, so when the wire comes off the top of the spool it still is in relatively big loops. I use the guide to neck the wire down before it enters the tensioner so it doesn't get caught where the wire enters the tensioner.

People also use funnels for this. I've used pieces of teflon tubing.

I have the winder in storage right now, so I'll have to go there to take another photo.

I gather you've had the unit apart. A useful photo would have all the pieces spread out on a blue background, with a steel ruler in the picture, for scale.

[JGundry]

Try two felts of lower tension. One near the spool and one near the wire guide.

[David Schwab]

It's a mystery to me how anyone can wind pickup coils at high speed at all, let alone control the scatter consistently.

It's not hard at all once you get the hang of it. I go really fast, and you just guide the wire back and forth.

As to the question, currently my fingers.

[Joe Gwinn]

As to the question, currently my fingers.

With sufficient practice, slotted calluses soon form and harden.

But the slots catch the guitar strings. Sad.

[David Schwab]

With sufficient practice, slotted calluses soon form and harden.

But the slots catch the guitar strings. Sad.

I already have calluses on my right hand index and middle fingers from playing bass, so there's no new ones forming! Plus I use my right hand, so even if I did have slots, it wouldn't affect my fretting hand on guitar.

When it starts to get too hot, I slow down my speed a little.

[Possum]

The Azonics DO work, you just have to NOT run the wire thru the spring dancer indicator wheel, I know of one major pickup maker who uses them this way. I'm not a fan of perfect constant force tension so I stick with my low tech flat washers with felt and thumbscrew.....

[Joe Gwinn]

The Azonics DO work, you just have to NOT run the wire thru the spring dancer indicator wheel, I know of one major pickup maker who uses them this way.

You know, I wondered if threading an Azonic to avoid the tension gage (and its big heavy dancer) would help, and you've confirmed my suspicion.

My thinking was running towards something like an Azonic but with an external and very light fishpole dancer to absorb most of the jerking due to the oblong bobbin, so the tensioner leads a smoother and better regulated life.

I'm not a fan of perfect constant force tension so I stick with my low tech flat washers with felt and thumbscrew.....

What I've seen in patents is two steel fender washers, each with felt stuck to one side, both on a steel screw with felt sides facing each other. The screw passes through a mounting plate and is terminated with a small washer and a thumbscrew. Between mounting plate and small washer is a compression spring. There is a simple guide to prevent the wire from getting caught up on the screw. All components are sourced from the local hardware store. The thumbscrew and spring together adjust the drag on the wire. The spring, which should be longish and soft, compensates for wear. The felt washers are allowed to rotate, to reduce grooving of the felt. To open the unit, simply press on the thumbscrew end compressing the spring, and the felt tensioner will open, allowing for easy threading.

[David Schwab]

What I've seen in patents is two steel fender washers...

Do we need gibson washers for PAFs?

each with felt stuck to one side, both on a steel screw with felt sides facing each other. The screw passes through a mounting plate and is terminated with a small washer and a thumbscrew. Between mounting plate and small washer is a compression spring. There is a simple guide to prevent the wire from getting caught up on the screw. All components are sourced from the local hardware store. The thumbscrew and spring together adjust the drag on the wire. The spring, which should be longish and soft, compensates for wear. The felt washers are allowed to rotate, to reduce grooving of the felt. To open the unit, simply press on the thumbscrew end compressing the spring, and the felt tensioner will open, allowing for easy threading.

Do you have a patent # for that? I'd like to see a drawing.

[Joe Gwinn]

Do we need gibson washers for PAFs?

It was in patents, but not claimed as an invention.

Do you have a patent # for that? I'd like to see a drawing.

Tanaka for one: US 4,526,329, Figure 3, start at object 44, which is at the bottom.

Maurice Brown of Azonic for another: US 3,837,598, Figure 1 object 33, lower right corner. This is the basic Azonic tensioner patent.

[ken]

I think the tensioner was designed for winding 28 gauge or smaller TV coils, many thousands of them of one kind before resetting. The knob at the top of the tensioner with the spring and the brake shoe mounting screws are the only real adjusters.
From 28 AWG (0.0137" dia single build) to 43 AWG (0.0025" dia) is a big jump, 5.5 to 1, and yet it can be teased into working.

What do the adjustments change?

Here is the photo of the 'interesting side' of the tensioner for reference.


As the wire comes off the pulleys at the tensioner's outfeed the wire pulls down on the arm and against the spring's tension. If the wire going through the tensioner loses its pulling force 'tension', the spring applies the brake pad against the inside diameter of the plastic ring slowing down the ring and increasing the tension of the wire. The big knob increases the spring tension which increases the output 'tension' of the tensioner. The single screw on the brake shoe adjusts the felt brake shoe for wear.

The black plastic ring is 3" diameter and 1/4" thick. It does seem to be injection molded or even turned on a lathe since all the corners are sharp. It isn't made of styrene or butyrate, after all these years it is still perfectly flat and hasn't warped or deformed. It's a dense plastic, it's relatively heavy.
I'd guess Bakelite, given the age and your description. And Bakelite easily does sharp edges. Modern winders seem to use nylon or delrin.

You mentioned that the tire in the pulley was some rubber O-rings. I'm guessing that it is a pair of rings side-by-side in a tight-fitting rectangular groove.

I think it might be Bakelite, and the groove in the center of the wheel the wire runs in is actually a round groove the O-ring tire fits very closely into. The wire goes between the tire and the ring. The alumiinm pulley on the left of the unit is thicker than the ring and has a large flat groove the ring fits into, and the two rubber tired pulleys at upper and lower right go into the ring's groove.

The Geo. Stevens winder runs at an average speed of 300 RPM at the mainshaft for round coils, I have my winder at 1/3 full speed or a little more to do humbucker coils. So, you are winding pickups at 100 rpm?

Actually, I'm not sure of exact speed, since I don't have the original motor pulley or a tachometer. Basically, the speed number I gave you was a SWAG. Roughly 1.75 revs per second is verry slow, so I'm wrong there. I guess I'll have to get a tach.

My problem was that the tensioner is only about 16" above the top of a five pound spool of wire, so when the wire comes off the top of the spool it still is in relatively big loops. I use the guide to neck the wire down before it enters the tensioner so it doesn't get caught where the wire enters the tensioner.
People also use funnels for this. I've used pieces of teflon tubing.

I have the winder in storage right now, so I'll have to go there to take another photo.
I gather you've had the unit apart. A useful photo would have all the pieces spread out on a blue background, with a steel ruler in the picture, for scale.

I had to take them apart to restore them, yes. I will have to take one apart again to rephotograph it.

BTW, Did anyone see this new Azonics Model 3535 tensioner for very fine wire?
Azonic Products Model 3535 Fine wire Tensioner - YouTube


ken

[Joe Gwinn]

Here is the photo of the 'interesting side' of the tensioner for reference.

I also found a bunch of photos you posted back in 2009, when you got the unit. A different kind of coil winder tensioner

As the wire comes off the pulleys at the tensioner's outfeed the wire pulls down on the arm and against the spring's tension. If the wire going through the tensioner loses its pulling force 'tension', the spring applies the brake pad against the inside diameter of the plastic ring slowing down the ring and increasing the tension of the wire. The big knob increases the spring tension which increases the output 'tension' of the tensioner. The single screw on the brake shoe adjusts the felt brake shoe for wear.

OK. That's how I guessed it must work.

I think it might be Bakelite, and the groove in the center of the wheel the wire runs in is actually a round groove the O-ring tire fits very closely into. The wire goes between the tire and the ring. The aluminium pulley on the left of the unit is thicker than the ring and has a large flat groove the ring fits into, and the two rubber tired pulleys at upper and lower right go into the ring's groove.

Ahh. Wonder why.

Actually, I'm not sure of exact speed, since I don't have the original motor pulley or a tachometer. Basically, the speed number I gave you was a SWAG. Roughly 1.75 revs per second is very slow, so I'm wrong there. I guess I'll have to get a tach.

How long did it take you to wind a coil of known turns count? That's likely close enough.

I had to take them apart to restore them, yes. I will have to take one apart again to rephotograph it.

Look at the old photos first, to see if there is anything still needed.

BTW, Did anyone see this new Azonics Model 3535 tensioner for very fine wire?
Azonic Products Model 3535 Fine wire Tensioner - YouTube

I had seen it, but am not clear on how it works. It does appear to be totally mechanical, but even that is unclear. I recall that this unit was offered to Possum in replacement of the unit with dancer that kept bouncing and breaking the wire, but Possum was unconvinced and gave it a pass. I suppose some questions are in order.

[Possum]

I'm using exactly what you described Joe, but you don't need any kind of spring. Just use thick felt washers, a spring is way overkill. I used the felt washers from an old Harbor Freight battery maintenance kit, I've got ten years use on it so far ;-) The tensioner is on the end of a wooden arm, take a look at Jason Lollar's winding machine, I just used the thumbscrew idea instead of a piece of folded felt with a clamp, because I wanted adjustable tension instead of just whatever force the clamp provided. The problem with all the "dancer" spring ideas is oscillation. Oscillation builds up and then it starts jerking on the wire instead of following the movement of the oblong coil and then it breaks the wire, every time. I tried all kinds of things, putting the tensioner way up on a pole far away from the wire guide, winding super slow which sort of worked if you want to take ten hours to wind one coil ;-) You can run the wire thru the dancer spring wheel on the Azonic and run it slow to get a tension reading, then remove it from that wheel, but you really don't need numbers, you just get to know by feeling the wire by hand as it goes onto the coil what the tension is and what kind of coil you're making. Thats all they ever did at Gibson was feel the wire by hand.

[SonnyW]

Just a note to agree with Possum, you don't really need the spring. My setup is different, but I just have the 1/4 inch thick felt in two tensioners and it has worked fine for the last two or three years. The only nice thing about the spring is that it looks like it would be easier to thread, but I think with the spring you would lose some control. The thumbscrew is pretty sensitive. After a while there will be some residue build up on the tensioner felt, I solved that by putting a small folded piece of craft felt on the first tensioner.

[Joe Gwinn]

I'm using exactly what you described Joe, but you don't need any kind of spring. Just use thick felt washers, a spring is way overkill. I used the felt washers from an old Harbor Freight battery maintenance kit, I've got ten years use on it so far ;-) The tensioner is on the end of a wooden arm, take a look at Jason Lollar's winding machine, I just used the thumbscrew idea instead of a piece of folded felt with a clamp, because I wanted adjustable tension instead of just whatever force the clamp provided.

Lots of people do it your way for sure, but the patents I've seen that use a felt pretensioner have the spring et al, mainly to make wire threading easier I suspect. And the spring-loaded assembly is easy enough to implement.

As for the felt, I was thinking of using the adhesive-backed felt sold in hardware stores for the bottoms of chair and table legs (heavy, usually tan to brown) or for the bottom of table lamps (lighter, usually green). Or, one can order the industrial stuff from McMaster-Carr.

The problem with all the "dancer" spring ideas is oscillation. Oscillation builds up and then it starts jerking on the wire instead of following the movement of the oblong coil and then it breaks the wire, every time. I tried all kinds of things, putting the tensioner way up on a pole far away from the wire guide, winding super slow which sort of worked if you want to take ten hours to wind one coil ;-) You can run the wire thru the dancer spring wheel on the Azonic and run it slow to get a tension reading, then remove it from that wheel, but you really don't need numbers, you just get to know by feeling the wire by hand as it goes onto the coil what the tension is and what kind of coil you're making. That's all they ever did at Gibson was feel the wire by hand.

The problem is that these dancers are not designed for winding oblong objects with thin wire at high speed, and have both too much mass in the end pulley and have too low a resonant frequency in the whole dancer assembly, and it's no surprise you couldn't make them work no matter what you did.

If you look at the family picture of the Tanak tensioners, you will see that the smaller units have lighter shorter dancers, and that the dancer tip idler wheels only appear in the larger units.

My current dancer design consists of a piece of 0.080" diameter music wire clamped at one end and with a bob made of delrin plastic attached to the free end. The delrin bob has two holes, one for the wire to pass through, the other to accept the end of the music wire. This hole is drilled undersize (0.0625" if memory serves) and the 0.080" wire is forced into the hole by clamping the wire in a vice and driving the bob onto the somewhat pointed wire with a big hammer, and is subsequently held by friction alone. In other words, this is a press fit, which works for delrin (but not many other plastics).

I measured the mechanical resonant frequency of a piece of 0.080" music wire held in a vice near to an old singlecoil pickup. The frequency varies with the free length of the wire: 4.5" -> 97 Hz; 5.25" ->74 Hz; 6"->62 Hz; and 7"->45 Hz. The mass of the delrin bob will reduce these frequencies by a little.

Now, if one is winding a bobbin at 1200 rpm, the bobbin rotates 20 times per second. Because the bobbin is oblong, there are two pulses per turn, so the pulse frequency is 40 Hz, so if the free length is 6" or less, it ought to work. If not, try 5".

[Possum]

I looked at the hardware store furniture padding things, some of them have really hard felt on them, you don't want that. Mine are soft felt and as mentioned very sensitive. The weight of the thick metal washers alone that I use is sufficient on some heavier wire I wind with so a spring would give way too tight tension. You do have to check tension often with a setup like mine because the wire wears a groove into the felt every time you rotate the felt to hit a new clean section or when you thread a different spool of wire thru it. If you watch the wire as it winds onto the pickup from the felt tensioner you can literally see how much the wire vibrates vertically to follow the oblong shape. Gibson's old winder they use now I think has horizontal felt tensioners on a rod with thumb screws going horizontally too. If you find the video of them building the Clapton 335 copy they show their vintage winder in action, its on YouTube for years now. I personally favor stupid low tech that works ;-) very low maintenance costs too ;-)

[Joe Gwinn]

I looked at the hardware store furniture padding things, some of them have really hard felt on them, you don't want that. Mine are soft felt and as mentioned very sensitive.

Yes, some are quite hard, which wouldn't work for very thin wire. But there is a whole spectrum of weights available.

For better tone, shouldn't you be using the same kind of musical felt as is used for piano hammers?

The weight of the thick metal washers alone that I use is sufficient on some heavier wire I wind with so a spring would give way too tight tension.

Could be. I note that Azonic uses molded plastic washers, while Tanac used deep drawn thin metal cups. In both cases, the machine screw is horizontal, so the weight of the washers doesn't affect how hard the wire is pinched.

You do have to check tension often with a setup like mine because the wire wears a groove into the felt every time you rotate the felt to hit a new clean section or when you thread a different spool of wire thru it.

This is a problem in production, and was the subject of some expired patents, one of which (don't recall the number) did note the grooving problem and solved it by allowing free rotation, to spread the wear out uniformly.

This sounds like a reason to use harder felt driven by a soft spring, but arranged so the pad can rotate freely.

If you watch the wire as it winds onto the pickup from the felt tensioner you can literally see how much the wire vibrates vertically to follow the oblong shape. Gibson's old winder they use now I think has horizontal felt tensioners on a rod with thumb screws going horizontally too. If you find the video of them building the Clapton 335 copy they show their vintage winder in action, its on YouTube for years now.

Re-Creating A Legend: The Eric Clapton Crossroads Gibson 335

Starts at 43:30 or so. Seems like a row of felt disks, with wire passing between disks. The felt provided the spring force.

I personally favor stupid low tech that works ;-) very low maintenance costs too ;-)

It's hard to argue with stuff that works, and the felt does, but it can be high maintenance in production, even if it never breaks - too fiddly.

[ken]

Just a note to agree with Possum, you don't really need the spring. My setup is different, but I just have the 1/4 inch thick felt in two tensioners and it has worked fine for the last two or three years. The only nice thing about the spring is that it looks like it would be easier to thread, but I think with the spring you would lose some control. The thumbscrew is pretty sensitive. After a while there will be some residue build up on the tensioner felt, I solved that by putting a small folded piece of craft felt on the first tensioner.

I have this on my handwinder too. I tried the spring too, but found the felt has enough springiness in it to work without it if you don't tighten things too much.

I'm wondering if the perfect wire tensioner for us is one with no dancer at all

ken

[Possum]

The dancer's only function is to measure the tension of the wire. The Azonic tensioners have gone up in price since I tried one, if you're running it without measuring the tension why even buy the thing? A felt works just as good, though maybe the Azonic wears more slowly so tension is more constant. I'm not really interested in cranking out lots of pickups anyway, so have no need of a winder you could theoretically walk away from. I'd never walk away from a running winder anyway, I watch each coil very intently.... Yeah the felt on piano hammers might work, but I think they'd be too hard. You might check McMaster to see if they have thick felt washers, I just had a couple sets of the battery felts sitting around so grabbed those...