Butyrate Bobbins

[belwar]

I understand, but you have to understand the research and the time that went into these. Not just our own research, but from other forum members as well (thank you velly much by the way!). There's only a handful of makers doing this and it makes it a little special.. If everyone had it, it wouldnt be special anymore!

I'm sure someday, some company will make butyrate bobbins for public consumption - but until then i'll use it to its full advantage :>

[bajaman]

oh okay - it's a secret handshake closed shop then
I am used to shared information not boasting
No need to read this thread anymore - lol
bajaman

[belwar]

oh okay - it's a secret handshake closed shop then
I am used to shared information not boasting
No need to read this thread anymore - lol
bajaman

There's a difference between shared information, and shared labor/parts.

I quite gladly give up vintage/rare pickup information publicly (i.e. Dearmonds, Wal Bass Pups, Tele p/u's, etc). Hell I destroyed almost $1000 worth of lane poors and posted all the results publicly with photos, measurements, etc. I even sell very good quality keepers to a few forum members too, but bobbins - i dont know - thats just different to me. I dont think its boastful at all, its a marketing tool and it would be foolish not to take advantage of that. I should also mention im an OEM and dont sell pickups to the public.

[JGundry]

Actually I gave some specifics that will be helpful for anyone who decides to get Butyrate bobbins molded.

The truth is there are a bunch of nitty gritty specifics that never get mentioned on this forum. Coming by some specifics can be pretty pricey. Those are usually not for public consumption.

I should probably add that there are a lot details that are open to interpretation and are dependent upon how attentive and patient the molder is with what probably seem like silly details to the molder. Getting original parts to reference is a the main thing to start with and that is not cheap. And even at that the bobbins Belwar and I did just are not going to look like the bobbins someone else does because of all of the variables. Although both might be very accurate to the originals.

[Manlius]

oh okay - it's a secret handshake closed shop then
I am used to shared information not boasting
No need to read this thread anymore - lol
bajaman

Kinda knew this would come at some point.....

Perhaps better than having something like this supplied to you via others hardwork that you pay a premium for, go out, problem solve, and you can end up with some pretty cool pieces on your own. This forum is full of boasting, but I don't think you will find it in this thread - they decided to show you the product in test run stages and let it be critiqued by people who really know what they are talking about. I would think that is pretty open and definately not some secret handshake society....

This thread was intended to show the fruits of some pretty serious effort and labor, and I think it is kinda immature to get upset that you can't buy them

But maybe I overreact - but you knew sniffling like this would come up!

[Possum]

....

The one thing that bothers me about them is the finish. All the PAF bobbins I have seen and own are high gloss and really jet black, see attached....

[JGundry]

Part of what you are seeing is the angle of the lighting. I wanted to get a little glare off them to get some detail. They are a deep black.

The PAF in that photo has been wiothout a cover for a long time. They take on a different patina when they have had the covers off for a while. Paf's do vary in gloss. I have had never uncovered PAF's in for repair with very little gloss to them with a lengthwise grain in the bobbin. I own a paf like this. I have also seen other uncovered one that are pretty shiny. The Butyrate can easily be buffed to as shiny as you would want. We went with the low end of the gloss figuring they could be buffed up from there if needed. Too glossy and it looks strange. It is a simple matter to polish the face of the mold further but we specifically asked for this sheen. Butyrate gets glossier the cooler the temp it is run at also. We are still sorting out the best temperature to run these at. Fine tuning the finish can be done later if needed.

[RedHouse]

The one thing that bothers me about them is the finish. All the PAF bobbins I have seen and own are high gloss and really jet black, see attached....

That PAF doesn't seem to have the spacing difference (screws -vs- slugs) being discussed in this thread.



Less shrinkage?

[JGundry]

It is a small difference but it is there.

[Possum]

...

What spacing difference? The PAF I have in now the pole spacing is identical, I can plug the slug bobbin into the pole bobbin top recess for a perfect fit.. the original drawings show identical spacing of pole centers for both bobbins...

[RedHouse]

What spacing difference? The PAF I have in now the pole spacing is identical, I can plug the slug bobbin into the pole bobbin top recess for a perfect fit.. the original drawings show identical spacing of pole centers for both bobbins...

Whew, thought I was seeing things (or not seeing things?).

[JGundry]

The diameter of the slug is .186"-.187". The screw hole for the head is .200" maybe a little larger. The old screw bobbin you have is probably warped also so the smaller diameter slugs will fit in the larger screw head holes no problem. As I said the difference is small but there is a little difference in the center to center spacing.

[frankfalbo]

If you consider the differing amounts/thickness of material in the screw bobbin vs. the stud bobbin, as the screw bobbin tapers, AND is threaded, AND the screws themselves are physically held in place by tight holes in the metal bottom plate which does not warp or shrink, then its feasible that slug bobbins, as they age, can pinch inward whereas screw bobbins would be forced to remain true to the original string spacing. The slug bobbin only has to tug on the two mounting screws in order to shrink inward. There's also winding pressure pulling inward, encouraging this movement in each bobbin, but the slug has little or no defense against it. The screw bobbin has the baseplate holes to reinforce it. Take a screw bobbin out, let it sit for 50 years, and I'll bet it migrates inward like the slug bobbin.

In talking to belwar we both agreed that a fair way to characterize this situation is that wrapping these bobbins is more like a PAF rewind, while something like a Seth Lover bobbin shot in the Hughes Plastics mold is more like winding on a new one, back in the 1950's.

[David Schwab]

The diameter of the slug is .186"-.187". The screw hole for the head is .200" maybe a little larger. The old screw bobbin you have is probably warped also so the smaller diameter slugs will fit in the larger screw head holes no problem. As I said the difference is small but there is a little difference in the center to center spacing.

Wouldn't you center the screws and slugs? You certainly wouldn't go by the outside two screws or slugs, since the slugs are larger.

If you keep the centers the same there will be no spacing difference, just a difference in hole size. Are you worried about one coil being .013" larger?

[JGundry]

If you consider the differing amounts/thickness of material in the screw bobbin vs. the stud bobbin, as the screw bobbin tapers, AND is threaded, AND the screws themselves are physically held in place by tight holes in the metal bottom plate which does not warp or shrink, then its feasible that slug bobbins, as they age, can pinch inward whereas screw bobbins would be forced to remain true to the original string spacing. The slug bobbin only has to tug on the two mounting screws in order to shrink inward. There's also winding pressure pulling inward, encouraging this movement in each bobbin, but the slug has little or no defense against it. The screw bobbin has the baseplate holes to reinforce it. Take a screw bobbin out, let it sit for 50 years, and I'll bet it migrates inward like the slug bobbin.

In talking to belwar we both agreed that a fair way to characterize this situation is that wrapping these bobbins is more like a PAF rewind, while something like a Seth Lover bobbin shot in the Hughes Plastics mold is more like winding on a new one, back in the 1950's.

Frank,

I will preface by saying that I think Seymour Duncan makes some great products and he is an inspiring example of someone starting small and growing a great business. He also seems like a great guy.

But since you invited comparison here it is. Seth Lover bobbins are WAY different than PAF bobbins. The bobbins that Belwar and I did are in fact WAY more accurate to a PAF bobbin from the 50's than the Seth Lover bobbins. Even against a time machine PAF bobbin the bobbins Belwar and I did are WAY more accurate than the Seth Lover bobbin. The Seth Lover bobbin mold is made by HPI but if it is the original PAF mold it is only the universal MUD base that is the same. The finished Seth Lover bobbin is so physically different from a PAF bobbin that there is on way the the actual molding parts are the same.

Here are just a few of the details wrong with the Seth Lover Bobbin when it comes to PAF accuracy. Belwar and I got these details correct.

1. Coil former not solid straight sided on Seth Lover.
2. Coil former dimensions are same for both screw and slug bobbins with the Seth Lover.
3. Notch gone from coil former interior by square hole.
4. Parting lines and gates different on the Seth Lover.

There are many more details and dimensions that I won't list.

If you do an A/B comparison it is obviously a different mold and design for the Seth Lover. The mold was marked HPI which is cool but means nothing. HPI also made plastic for the inside of Whirlpool dishwashers. HPI is the logical place to have make this mold and they would have been the first stop to get a quote from as I am just an hour away from Benton Harbor. But HPI went out of business in the 90's.

As far as plastic shrink over the years I asked our molder about this very issue before we had the mold made and he said shrink after molding was not a factor.

Just to clarify the Bobbins Belwar and I did are WAY more accurate to an original, new 50's PAF bobbin as it popped out of the mold in the 50's if you are comparing it to a Seth Lover bobbin. Seth Lovers are very nice pickups though.