Real NOS PAF era plain enamel wire....

[Steve Conner]

If the spool was wound with constant torque on the spindle, the inside layers would be tensioned more than the outside.

[RedHouse]

Yes, that's quite true, but they're not wound by torquing the spool but using elaborate tensioning-wire-guide apparatus.

BTW, I love your sig-note, "douchebaggery" what a word!
(and how true it is)

[Fuzzy Logic]

This is Rola enameled wire data from 1954. And, as to save some people the trouble of downloading the attachment, it is not data of "plain" enameled wire and this wire was not made in the USA but in Australia.

Nevertheless, of few things may be of interest.

1. On page 5 it can be observed that the diameter values of the wire gauges 41-44 differ from the "official" or "published" values. AWG 42 is on this page defined as having a diameter of 0.0024" (instead of 0.0025"). On the other hand, on page 11 they use 0.0025" for the AWG 42 wire size of their new wire. There appears to be a transitional thing going on here.

2. The permissable enamel addition is specified on page 5 as being 0.0002" to 0.0004" for AWG 42. Nowadays it is more like 0.0002" to 0.0003".

3. On page 11 the ohms/1000 foot for AWG 42 is specified as being 1673 Ohms (a conductivity which is a little below 100% IACS).

[Fuzzy Logic]

Its the "real life" part that only concerns me. You just have to buy from different sources and wind the stuff to really know what it is and what you can use it for.
REA spools used to all have ohms per foot specs written on them for each spool.

I just opened a new roll last night. The outer windings are a whole .0001" thicker than the last roll's inner windings. Doesn't sound like much but makes a big difference in size of coils when you got thousands of turns on the pickup, that small difference adds up fast. I try to burn off the thicker part of the rolls on pickups like Tele bridges etc. to get down to the diameters I need. Everyone's wire is a little different, Wirenetics for example sells Elektrisola product but its like they buy the cast off over-spec spools or something because the diameters on everything they sell it seems are overboard sizes, FAT. But for certain pickups you WANT fat wire, so I go to them.

Fralin used to say that they would wind a test pickup on every new roll of wire they got in, but its not really a great method because of the stretched wire in the core of the roll. But the only way to know any wire isn't by reading specs, you have to work with it and it'll let you know real fast whats its good for and what its not good for.

But isn't that 0.0001" difference in diameter less than the inherent tolerance for the wire size you buy, provided that the diameters of those two wires are somewhere within the range of 0.0024" - 0.0026" (for AWG 42) ? Even when buying min-nom or nom-max (I have no idea if you can actually buy min-nom or nom-max Elektrisola wire) one should not be offended by a difference of 0.0001" between two spools (or even within the spool).

BTW; I think that coil size differences due to an increase/decrease in wire diameter are more directly related to the number of layers instead of to the total number of turns on a bobbin.

[David Schwab]

But isn't that 0.0001" difference in diameter less than the inherent tolerance for the wire size you buy, provided that the diameters of those two wires are somewhere within the range of 0.0024" - 0.0026" (for AWG 42) ? Even when buying min-nom or nom-max (I have no idea if you can actually buy min-nom or nom-max Elektrisola wire) one should not be offended by a difference of 0.0001" between two spools (or even within the spool).

I use mostly Elektrasola wire, and the label says "min nom" and they write the actual measured diameter for that roll in pencil. So clearly there is a variation in sizes within the min nom tolerance.

I have never heard any difference in tone from one roll to another.

BTW; I think that coil size differences due to an increase/decrease in wire diameter are more directly related to the number of layers instead of to the total number of turns on a bobbin.

Probably. Different size wires sure to give a different tone, as do wire insulation thickness. I'd bet if anyone hears a difference in insulation types it's because of the thickness of the insulation.

[JGundry]

This is Rola enameled wire data from 1954. And, as to save some people the trouble of downloading the attachment, it is not data of "plain" enameled wire and this wire was not made in the USA but in Australia.

Nevertheless, of few things may be of interest.

1. On page 5 it can be observed that the diameter values of the wire gauges 41-44 differ from the "official" or "published" values. AWG 42 is on this page defined as having a diameter of 0.0024" (instead of 0.0025"). On the other hand, on page 11 they use 0.0025" for the AWG 42 wire size of their new wire. There appears to be a transitional thing going on here.

2. The permissable enamel addition is specified on page 5 as being 0.0002" to 0.0004" for AWG 42. Nowadays it is more like 0.0002" to 0.0003".

3. On page 11 the ohms/1000 foot for AWG 42 is specified as being 1673 Ohms (a conductivity which is a little below 100% IACS).

An interesting fact as it relates to overseas magnet wire. When I bought my old Gibson made winder from Heritage Guitar they still had boxes of 44AWG Poly wire from the Gibson days. The wire was made in Italy and it was on what I believe were pressed fiber spools and I would guess they were from the 60's or 70's. Why did Gibson buy 44 AWG wire from Italy? Probably because they could save a buck on it. My point with this is perhaps this explains the smaller diameter wire that is on some hotter 59' era P.A.F.'s. Maybe it was 42 AWG from an overseas wire maker that had a different min. tolerance for 42AWG that a USA wire maker would have. Just a thought.

[Possum]

That .0001" difference blows the coil SIZE up very noticeably when using a standard turns count recipe. If you have limited space it can be a problem.
I've heard various theories about why the PAF wire diameter changed, the dies wore out etc. etc. no one really knows. But we saw the same thing with REA Magnet wire, it went from being very thin to being very thick wire in the space of about 3 years, all from one company. It totally played hell with what I was making at the time.

[WolfeMacleod]

Elektrisola never varies, and since I use turn counts I know what the DCR of the finished product should be, no need for anything further than that. Its the same thing anyway, 5000 winds in a recipe equals a certain DCR in known wire, if it starts coming out noticeably different then something went wrong in the coil. I know Wolfe is really into ohms per foot last I heard but then that was in REA days when it would of been helpful. I kind of don't see the point anyway since I'm not winding to "ohms." .

I still pay attention to Ohms Per Foot, and yes, Elektrisola does vary, and quite a bit. I have a very specific range of wire I will accept, plus or minus about 10ohms per 1000 feet. Anything over that, and I have to add or subtract turns. Ohms + Turns counts = consistency, and I know that if I have "X" turns = "X" ohms at "X" degrees that my tension is also "pretty damn close"

[Possum]

With the varying diameter thru the spool I personally stick with turn count recipes. So pickups from the start of the spool measure a little lower in ohms, and higher at the end of the spool, but its not enough to concern me. I think things like capacitance and the various spooky eddy current things probably remain pretty constant with using turns counts because I don't hear dramatic changes in tone enough to be concerned about. My Elektrisola spools diameter at beginning and end of the spools since they started making PE for MWS has all been very stable in size, am really thankful for that.....