Hey Seymour!! ... what is ICPC and how do you fix it?

[tone4days]

in this video


which shows him working on a '54 strat pickguard, seymour talks about the acronym ICPC and then says it means "inter pole coil corrosion" ...

what is that?
what causes it?
how do you know if a pickup has it?
how does it get corrected?
can the pickup be saved?

any of you guys have experience with it?

 

[ganzosrevenge]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

it seems like when the wax or the coating around the wire corrodes causing the copper to touch copper and act like one BIG wrap instead of a zillion little wraps.

 

[JOLLY]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

I found these on the net.

"ICPC (inner coil pole corrosion) or rusting of pole pieces. The coil will have to be completely unwound to the break and rewound."



"333. Why are some Fender covers made with holes and others without, as used on Duosonics and Mustangs?
The cover is basically a component that protects the coil and especially helps keep the string from getting snagged under the lip of the pickup. The Duosonic and Mustang have basic single coil pickups using .625” length rod magnets. The pole pieces are flush with the top of the pickup so there is no need to have a cover with holes. The solid top cover is important for Mustang guitars because the switching circuit could reverse the electrical phasing of the coils. When reversing the lead wires, the pole pieces will buzz if touched. The solid cover eliminates accidental touching of the pole pieces. Also the solid covers help keep moisture from penetrating down into the coil which could eventually cause ICPC within the inner coil. ICPC is “Inner Coil Pole Corrosion” which I have found can cause perfect looking pickups to fail. ICPC is caused when moisture rusts the magnet at the coil beginning and breaks down the insulation on the magnet wire eventually causing the coil to fail."



"568. Can humidity cause any harm to pickups?
Humidity and all kinds of moisture from sweat and condensation in a case can cause all kinds of problems with your instrument. Humidity can cause oxidation on switches, potentiometers, jacks and rust hardware. Constant moisture on an instrument will cause ICPC (inner coil pole corrosion) where the magnet can rust inside the bobbin due to exposure to humidity and moisture. When a magnet rusts or oxidizes, there is a break down of the magnet wire insulation and exposes to bare copper magnet wire. After a period of time the bare magnet wire can oxidize and breaks eliminating a signal from the pickup. Try to keep your instrument dry and avoid hot trunks in your auto that can cause condensation in the case due to the high moisture content in the lining of your case."



"The worse case scenario with rusty poles is that they will rust all the way down to coils and eventually eat away the coil wire insulation causing the pickup to short out. This is called ICPC (inner coil pole corrosion) and usually takes years and years of consistent sweat and rust."

 

[Zerberus]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

^^ nailed it

 

[tone4days]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

very cool - thanks

so this leads to my confusion ...

i understand that the (magnet) pole pieces can rust

i understand that the insulation around the pickup wire can become degraded such that the wind shorts out

but i am not seeing how a pole piece magnet comes in contact with the coiled wire

isnt there a gap between the coil and the pole pieces that is created by wrapping the wire into a coil around the bobbin?

do i understand this correctly?

or is there an electro/mechanical connection (i.e. solder joint, etc) between the pickup coil wire and the pole piece/magnet ?

help me out

thanks
t4d

 

[Zerberus]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

You are missing something: in single coils, the wire is wrapped directly around the magnets. There is no plastic in between, the insulation is in direct contact with the magnet on one side and the wire on the other

 

[glassman]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

Strat pickups are wound with Formvar insulated magnet wire which crazes in the presence of moisture. Crazed insulation, under a microscope, can look like anything from micro-cracks through individual layers of insulation to full depth cracks through to the bare conductor. Modern Formvar has a polyurethane component that lessens this effect but it still happens; mainly when the insulation is only moderately cured. In fact, resistance to crazing is a QC test performed at most magnet wire manufacturers. Formvar is the only insulation type that crazes in the presence of moisture.

 

[Sanford]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

All this info furthers the argument that "just because it's vintage doesn't mean it's the best." Improvements have been made and tone has not necessarily suffered because of it.


BTW, love the avatar, glassman! It's like Escher doing abstract eroticism!

 

[tone4days]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

You are missing something: in single coils, the wire is wrapped directly around the magnets. There is no plastic in between, the insulation is in direct contact with the magnet on one side and the wire on the other

well that thar 'splains it all
thanks tim

 

[tone4days]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

i wonder if anyone has investigated a micro coating for magnet rods that is magnetically neutral but moisture resisitant

 

[idsnowdog]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

I left my laptop in my car last night. This morning I had an Icy PC.:bigok:

 

[Simon_F]

Re: Hey Seymour!! ... what is ICPC and how do you fix it?

I remember reading interviews with Rory Gallagher where he said one or more of the original pickups in his Strat had failed and been replaced. Never understood how that could happen, but this seems to explain it. He was known for sweating a lot during gigs! Interesting stuff.