Magnet insulation

[Possum]

Fralin...

There is something Lindy isn't telling about here, I just tried two different brands of spray lacquers both cut through really easily. The stuff on his magnets is very hard to cut through. Will baking nitro in an oven harden it, or are there hardener sprays for it or something? His stuff does dissolve in lacquer thinner, but I'm stymied what the heck he uses, its sure not any spray or can lacquer I've tried and I'm up to five different brands now.....

[Possum]

glyptal....

Where did you buy the Glyptal?

[David King]

I think I mentioned a few pages ago that nitro takes a month to harden. If you sprayed these magnets last night the nitro might be dry but it will still be very soft.

[EtLa]

Where did you buy the Glyptal?

ask any electric motor services they dip (insulate) the motor winding in Glyptal. BTW It can be bake 2 hours at 130C

[kevinT]

its sure not any spray or can lacquer I've tried and I'm up to five different brands now.....

I bought a can of brass lacquer to try out. I'm wondering whether it would adhere to and insulate the magnets more effectively because it was formulated for metal instead of wood. The only issue is that it is high gloss. Has anyone tried it?

Finding it difficult to locate dealers in the USA selling Fiddes lacquer....no success yet.

http://www.woodcraft.com/family.aspx?FamilyID=3260

[EtLa]

I have a 64 strat pickup to rewind that Fralin rewound about 5 years ago and there is something on the magnets but... I have no clue at all what it can be.

[madialex]

Where did you buy the Glyptal?

Hey Possum, I talked with an electronics friend today and he said they use some sort of epoxy stuff on their circuit boards that is hard as nails, very thin and they bake it at 85 degrees for 8 hours and is supposed to be bullet proof. He is checking on what it is and where they get it. Will post findings then.

[GlennW]

Is this the same Glyptal that people use to paint the insides of engine blocks?

[Possum]

cool.....

I hope you can find out about the circuit board stuff, I found mentions of that stuff but only on industrial sites....you know the guys who never answer email unless you want to buy 50 gallons of something. Sounds like a good bet. For sure no one is going to let their bobbins sit for a month to harden. Did car paints used to be baked to harden? I keep thinking there's something thin you could dip then bake....

[mick]

2 pac would be hard enough but it's pretty funky stuff to use...apparently...

Mick

[Sweetfinger]

Just a bunch of info and musings...

Part of the problem here is that everyone is referring to 'lacquer' but saying just that is about as helpful as saying "I wound my pickup with WIRE". Here's some thoughts:

'Lacquer' sort of refers to any finish that cures by evaporation of the solvent medium and can therefore be re-dissolved after drying to allow adhesion of subsequent coats of finish, or seamless spot touch-ups.

I say 'sort of' above because many products today that are labeled as 'lacquer' are not stricly evaporative finishes and polymerize to some extent.

Most modern finishes are not evaporative finishes, and combine (polymerize)with oxygen in the air, or water vapor to chemically form a harder, more durable finish which, unfortunately, can't be completely re-dissolved by the original medium. Even more durable finishes come from 'two part' systems which chemically combine to form a paint film that is very resistant to even strong solvents.

Any lacquer, and most polymerized paints, and even many two-part catalyzed finishes can be dissolved, or softened with lacquer thinner, which is a blend of various solvents, but when the solvent evaporates, the stuff that is left over is no longer a viable paint because the molecular bonds have been broken leaving the long-chain polymers broken into shorter, weaker chains. Fer instance- Super glue cures by combining with water vapor or water molecules to form really long molecular chains. Cured super-glue can then be completely redissolved in acetone, and you can actually use it again, but the chains are broken and no longer able to link up together as they did the first time, so the glue is much weaker, what you end up with is kind of a crappy acrylic based lacquer! ----- essentially, just because you can dissolve a finish with a solvent, doesn't necessarily mean it was originally an evaporative lacquer.

BTW super glue isn't nearly as toxic as people think it is, certainly no more than any lacquer or house paint, probably less. The cyanide molecule(as in cyano-acrylate) is locked up tight molecularly during manufacture, and by the time you're using the glue, it doesn't ever get out. CA glue fumes are irritating but you'd really have to do something stupid to kill yourself with them.

Nitrocellulose lacquer is extremely difficult to casually step out and buy at a store these days. It is considered an antiquated specialty finish and you would have to special order it from most purveyors of paint.

Most of what you'll buy as 'plain ol' lacquer is likely some sort of acrylic lacquer which may, or may not actually polymerize during drying. Other than places like Stew-Mac or the like, I'd bet that ANY spray can lacquer is NOT nitrocellulose based.

Some airplane finishes, aka 'fuel proof dope', might still be nitrocellulose based, but are more likely to be butyrate based lacquer, which is probably closer to nitro than acrylic lacquer, but doesn't really matter that much because, like any hobby paint, it comes in small bottles with a relatively high price.

The 'whitish' color referred to in previous posts is called 'blushing' and comes from applying lacquer when it is humid, or from heating/steaming. There are various retarders avail that you can add to lacquer when you are spraying that will minimize blushing, and a light overspray of retarder will remove blushing in some cases(like after you've steamed a neck off an old acoustic guitar)

Sure, lacquer seems dry after half an hour, but it actually takes many WEEKS to fully dry. Lindy Fralin's lacquer may be really hard on a two year old pickup, but could have been softer when the pickup was new. I'd recommend letting at least two weeks go by before winding a dipped bobbin.

You should probably thin most lacquers before dipping, but not with lacquer thinner. most thinners are blends of many different solvents designed to keep brushability/sprayability/working time within certain parameters. These parameters aren't necessarily a concern for dipping pickups. I'd recommend a very fast evaporating pure solvent like acetone. Also, if you're worried about insufficient film thickness, two really thin coats with sufficient drying time between are going to work better than one thicker dip. IMO one dip in thinned finish with sufficient drying time should work great.

Somebody out there should try good ol' fashioned flake shellac thinned with denatured alchohol. That should work pretty well and dry faster than lacquer.

For the more impatient, the extremely thin super glue would be my choice. I'd try dipping the mags before inserting into the flatwork. also remember that just because CA bonds 'instantly' doesn't mean it is completely cured. CA glues need a day or two to reach full hardness.

[Joe Gwinn]

Hey Possum, I talked with an electronics friend today and he said they use some sort of epoxy stuff on their circuit boards that is hard as nails, very thin and they bake it at 85 degrees for 8 hours and is supposed to be bullet proof. He is checking on what it is and where they get it. Will post findings then.

Be careful of one-part systems that claim to be epoxy. While it may be a fine system, it isn't going to be the real thing. Real epoxy conformal coating systems are two-part, but cure very slowly at room temperature. I recall using one system where we mixed a day's supply in the morning and used it all day. The solvent would evaporate fairly quickly from the coating (applied by dipping), leaving a sticky film that hardened in the 150 F oven in perhaps an hour. At days end, unused mixed material was discarded. It made a very good finish for wood, and for brass, and many people brought items in to be coated with the discarded material.

Here is an acrylic lacquer intended for circuit boards, and availalble retail: http://www.mgchemicals.com/products/419b.html.

[Spence]

Nitrocellulose is available here:

http://www.stewmac.com/shop/Finishin...E.html#details

That wasn't hard was it!

As I have already mentioned, nitrocellulose can be oven cured in half an hour.

Why not just bloody try it instead of pissing around. I use nitrocellulose day after day and it works just like it worked for Fender. What's the problem with that?

[Possum]

StewMac no good.

This is stringed instrument lacquer and is what I dip my bobbins in to seal and hold them together as glue. Its quite thin and won't insulate at all, its also why I went to taping the magnets. I didn't know there were other versions of lacquer and why I now have about five different cans of the stuff from very thick stuff to miniwax which never dries even when baked :-)

[Possum]

ordered the stuff....

Had a hard time finding any place that actually sells that PC board stuff, but finally did. Expensive with shipping almost $20 a can, will let you know how it works....