Should I grind my G poles down

[jefrs]

My Kent Armstrong Vintage Strat pickups are all too strident on the G.
No surprise with a plain G and staggered poles pieces.

Should I grind the G poles down level with the B ?

Is this do-able ?

Will I destroy the AlNiCo magnets by heat and/or vibration ?

Is there another solution ?

TIA - Jeff.

[BritishBluesBoy]

I wouldn't recommend doing that. Have you tried adjusting the pickup height? Perhaps new pickups are in order...?

[Talmir]

I saw the production head at Seymour duncan talk about how alnico magnets get degaussed by shocks and tremors.. So grinding it down might be a pretty bad idea :P

[Chris Leger]

Heat will demagnetise them. If you have to shorten them, use a file.

[Casual_Reader]

Originally Posted by Chris Leger

Heat will demagnetise them. If you have to shorten them, use a file.

from this page on the Bill Lawrence site:
http://www.billlawrence.com/Pages/Pi...gy/magnets.htm

"Magnets are sensitive to heat, but so is your guitar. However, heat can be a severe problem when an Alnico 5 magnet is exposed to temperatures above 1000 F, approaching its Curie temperature of 1634 F. At these temperatures, Alnico 5 undergoes structural changes and cannot be re-magnetized. Why do I mention this? Because it happens quite often, when someone doesn't like the unbalance in output of a pickup with staggered magnets and goes to a bench grinder or a belt sander to grind a magnet down. You take a chance that a magnet gets too hot and becomes damaged."

[jefrs]

Yes, I have adjusted them. Yes, I know heat and shock embugger/demagnetize them.

These are Kent Armstrong STV at £37ea, new pickups are not required, they are Vintage pattern, so is their stagger - for a wound G, otherwise they sound just fine.

I was wondering if anyone had successfully shortened an AlNiCo. They are remarkably hard and resist files. It is possible to grind without overheating but risky, you don't get a second chance. And you get magnetic dust/filings everywhere. I was thinking Dremel, not the bench grinder. But I'm prepared to sacrifice a few files, not pickups.

Has anyone actually done this ?

[Zhangliqun]

Aside from heat/shock/trauma -- which can still be fixed by remagnetizing -- your bigger problem is finding a tool hard enough to grind down Alnico. Alnico is one of the hardest substances known to man.

You're better off just buying a new pu with the stagger you want.

[benbo]

DON'T DO IT! It's not worth messing the PU up for a very small difference in output. You cant file them with a file as they are very hard and don't file easy. Grinding them can be done but I would suggest DE-magnetizing them first for 1- the magnetic dust sticks to everything metal and 2- the heat will kill it or DE-mag it to the point of not being very audible. You can always re-magnetize the whole PU afterwords.

PS. The heat may also melt the insulation on the coil wire against the magnet and cause the PU to short against the magnet

[Tony Reid]

On pickups that are only lightly potted you can simply push the G pole down with moderate thumb pressure. I have done this on many sets of Strat pickups without any problems. If the pole doesn't move with medium pressure, don't force it (e.g. by using a small hammer) - then you would be taking an unnecessary risk and could short out the pickup.
Alternatively, just angle the pickup so the low E side is about 1-2/32" lower than the high E side (measured from the top of the pole piece to the bottom of the string pressed down at the top fret). Also deliberately strike the G string with less force than the other strings when playing clean. With a bit of practice this will become automatic, especially if you listen for changes in tone as you strike the string harder or softer. At high volume and with distortion, the natural compression (of amp and/or pedal) tends to even things out anyway.

[PCR985]

I've never been a fan of a loud G. That's why I always specify low G poles when I order pups. Be careful pressing magnets. Some wires are glued to the magnets. You run the risk of breaking the wire in this case. If I were you, I would contact the manufacturer and ask if the pole can be pressed down.

[Armo]

You can tap them with a hammer. Make sure that all the base of the pickup around the pole is supported, place a small piece of wood over the pole and give it a quick tap. Once loosened you can slide it by hand to required position. I managed it with my strat pickups but it comes with no guarantee and comes under kill or cure.

[Tele Jr]

Ditto what Armo said, you should be able to just push the pole back down into the bobbin, no grinding/filing required.

[jefrs]

Thanks, I shall try pressing it down, I have the technology for that - a vise with a nut to support the coil and let the magnet through. I also have some 'sacrificial' pickups to experiment on.

Of course the industrial method of grinding magnets is to use a continuous flow of coolant over the job, that's just so not going to happen with the coil in place. I do however have one of those slow, water cooled, whet stone wheel, bench grinders. Or the Dremel.

re demagnetizing a pole, the original middle pickup was supplied with a totally dead top E pole, it was immediately replaced without question by the shop.

BTW 'blutack' is very good at removing magnetic detritus from pickups.

[jefrs]

Ok, that works on a Wilkinson, in fact once the vise easily got it shifting, I could move it with my thumb.

Assuming the poles are of equal magnetic strength, then distance is the most important factor in a pickup. It's to do with the field strength being disrupted that induces the signal in the coil. The trick is to get the field strength to suit each string, each one has a sweet spot..

Thanks again.

[jefrs]

Follow-up report.
Kent-Armstrong STV (strat vintage) pickups have the poles all the same length, the stagger is achieved by setting them at different heights. On the Wilkinson Vintage the poles were different lengths. The Kent-Armstrong poles are considerebly tighter in the former than the Wilkinson's.

In the end, I used an engineer's clamp rather than the bench vise, with a nut to accept the pole as it came down. Again, once it had moved I could adjust it by hand, only this time I had to use a small block of wood as a pusher.

The G poles are now flush with the cover and are the lowest poles, the B being slightly higher, the A and bottom E are next and about equal, then the top E, the D is highest. The G used to be the same height as the D. Strings are Thomastik-Inspiron Power Bright 10-45. Floating tremelo with 3 springs and the tail about 1/8-in off the deck. I adjusted the pickups up, fore and aft, until they came on song, they are quite high. The bridge is highest, then the neck, then the middle. The note is clear and clean, I have to push the gain way up to get the amps overdriven. I probably have not finished playing with their heights - any advise?

Adjusting the G to the correct height (modern stagger?) has made a /lot/ of difference and it is much nicer to play. The G no longer barks and overwhelms the rest of the set.