Cracks in bobbins?

[Mincer]

I've owned these pickups for probably 20 years, and they have hairline cracks in the bobbins. Anyone else have these? It doesn't affect the operation of the pickups, but I've never had this issue with plain black bobbins. Maybe it is the white plastic they were using back then? Maybe it is the result of performing outside in Florida the last few decades? No idea. Weird, though!

I think at one point, SD reached out to me after seeing a pic on social media asking if I could send them back so they could inspect them, and they sent me a set of pickups for my trouble- and they sent these back to me, too. This was well before I worked for them in the early 2000s, I guess.

 

[beaubrummels]

There was a thread on here about bobbin cracks. Small hairlines near the poles is normal, my understanding from that thread is it's a result of the thermoforming or molding process of the bobbins. Don't know if having them grow out to the sides of the bobbins is normal. Plastic is pretty resilient to temperature changes. Unless it's something like poly-carbonate which is strong but brittle.

 

[GuitarStv]

I've got a 23 year old '59 neck in double cream that has developed a couple cracks from the poles under the high and low e out to the edge of the pickup. Doesn't seem to cause any problems so I've just been ignoring it.

 

[ehdwuld]

There was a thread on here about bobbin cracks. Small hairlines near the poles is normal, my understanding from that thread is it's a result of the thermoforming or molding process of the bobbins. Don't know if having them grow out to the sides of the bobbins is normal. Plastic is pretty resilient to temperature changes. Unless it's something like poly-carbonate which is strong but brittle.

yeah while I remember the thread
I cant recall its contents

 

[AdrianSD]

​

2018 Custom Custom and 2019 Jazz, the only white Duncans I got. To my ears the cracks have a positive impact on the tone, kind of sound more open with more definition in the low mids, the chords ring out clear and have a distinct personality. I wish I had more pickups with cracked bobbins, basically a free mod.

 

[ehdwuld]

Tone cracks

 

[Securb]

It happens all the time it is just not as noticeable on black pickups. Next time you are in the music store take a close look at some of the older axes

 

[AdrianSD]

It happens all the time it is just not as noticeable on black pickups. Next time you are in the music store take a close look at some of the older axes

Yeah, just checked some of mine, one of my black JBs has hairline cracks that aren't scratches. Had to wipe it and look closely to notice them.

 

[ICTGoober]

It's a problem with the formula of the material. Too much this, too little of that - and you've got cracks. I'm no expert on plastics, but my brother is - and I've picked up a little in 40 some years from him.

 

[Mincer]

I am not bothered by the cracks at all, and surprised they aren't even worse due to the heat and humidity here. As long as they work, I'm good.

 

[Masta' C]

I've had dozens of SD's with small cracks between poles, but this may be the first time I've seen the cracks extend outward like that!

 

[Mincer]

I never leave my guitar in the car, but playing outside here can absolutely be brutal on any gear. This guitar has hairline cracks in the finish as well much like the bobbins.

 

[hamerfan]

I have seen the worst and longest cracks on white bobbins. Never on blacks.

 

[Mincer]

I have seen the worst and longest cracks on white bobbins. Never on blacks.

Yeah, I was wondering if the formulations of the bobbins was different for different colors...

 

[switchman]

Sorry if I'm stating what's obvious to everyone, but isn't this just plastic shrinking over time? I know very little about the chemistry of bobbins but I thought some types of plastic are very prone to instability. Plastic Martin pickguards and Kluson tuner buttons shrinking or crumbling have been repair issues for a long time.. Or budget Suncoast outdoor storage bins

The slugs are a very tight press fit. If the plastic shrinks at all from its ongoing internal chemistry changing or a reaction with the environment, there's nothing it can do but crack. I had two pairs of Wilde L-280's which were similar construction with non-removable formed covers. The black were fine but the cream cracked just like these.

 

[Artie]

A couple of my Duncans do that. They still sound good. And if you sell them, you can charge extra 'cause they're "reliced."

 

[GuitarStv]

I have seen the worst and longest cracks on white bobbins. Never on blacks.

So the crack epidemic mostly impacts whites? Interesting . . .

 

[Mincer]

A couple of my Duncans do that. They still sound good. And if you sell them, you can charge extra 'cause they're "reliced."

That's where I keep the extra tone.

 

[ehdwuld]

That's where I keep the extra tone.

Too toned

 

[Artie]

Two toned

Fixed.