Paraffin types...

[Jeff Callahan]

Hello Pickup Makers,


Just curious on what type of paraffin people recommend for potting. I've always used the canning stuff, but I got a new melting tank and need a lot of the stuff. I did a little internet shopping, and realized there are many different types (IGI 1230, IGI 2281, etc.) with different melting points. Just curious if anyone out there has an opinion on this.

Thanks,
Jeff

[big_teee]

I've used gulf wax paraffin, and some scrap candles.
Candles are usually a harder wax.
My complaint with harder waxes is they flake when cold, and the flakes get on things.
You can thin your wax with bees wax or a liquid paraffin.
Liquid paraffin can also be called kerosene.
I thin the wax so that when cool it is not as hard, and is a little greasy feeling when you rub it.
Gulf wax is softer and melts easier than most candle wax.
You can also get scented waxes that are used for hand joint problems, & for waxing, or hair removal.
Most of these waxes are already thinned some.
I use liquid paraffin used in oil Lamps for thinning.
YMMV,
T

[Leo_Gnardo]

I'm not a pickup maker but on occasion a pickup dipper. It's all worked out great so far. I use beeswax or 50/50 beeswax and block paraffin sold in groceries for canning and candle making. I find beeswax a little "stickier" than plain paraffin. Terry, a lot of candles are made with a mix of paraffin and stearic acid, which gives them a flaky apperance and (I'm guessing) increases the melt temperature so the candles don't bend. Beeswax melt point is 145 F. Some might want to use a lower melt point paraffin in order to avoid damaging lacquer insulation on windings. The offset to that is, sometimes guitars can unintentionally get baked, left in cars or other spots. As a traveling guitar tech, I used to keep a cheap Radio Shack hi-lo recording thermo-hygrometer in one of the guitar trunks. Then I'd have some idea what max and min temperature and humidity the instruments had been subjected to. One fine day in Kauaii Hawai'i the meter read 137F. The gear had probably been left out baking in the sunshine at the Honolulu airport before it was transferred to Kauii. FWIW hide glue is reported to soften up @ 145F also. This time we narrowly escaped having a nice old Gibson 225 neck reset itself. Besides unplanned neck resets, a superheated guitar might start losing wax from potted pickups, and worse things besides.

One potential drawback to beeswax, if you're playing outdoors in nice weather, curious local bees might come over to check out your axe.

[big_teee]

The melting point is lowered when thinned.
My biggest complaint with bees wax is the cost, & local availability.
We just thoroughly discussed this, in this thread.
If you read this maybe it won't all be required again. lol
http://music-electronics-forum.com/t31683/#post345736
http://www.prochemical.com/MaterialS...es/Beeswax.pdf
http://www.prochemical.com/MaterialS...ffin%20Wax.pdf
http://isites.harvard.edu/fs/docs/ic...araffinoil.htm

[jack briggs]

I use straight paraffin - the stuff Mojo sells. BTW - paraffin has a lower melting point than beeswax.

[Leo_Gnardo]

My biggest complaint with bees wax is the cost, & local availability.
We just thoroughly discussed this, in this thread.
If you read this maybe it won't all be required again.

Yes beeswax around here is $15-20 a pound in the hobby shops. If you happen to know a beekeeper, might get some a lot cheaper. Of course you can get all you want if you have your own bees. I just read my municipality has a new regulation, can't keep horses, cows, chickens, lizards or BEES. But rats are OK with the politicians. Their relatives??? I'm inclined to get a beehive or three and train 'em to sting the moron politicians. Also to hook up a sound effects CD to a PA speaker and blast the mayor's house with cocka-doodle-doo each morning about 4:30 AM. But anyway - a pound of beeswax can pot an awful lot of pickups for 25 cents or less each, if that's your choice. Won't break the bank.

LOTS of good discussion in that thread Terry, thanks for reminding us & posting the link. I'm chuffed that Bruce Johnson mentioned his epoxy method. It's permanent but I bet it works great. Also diggin' Chuck's adventures with his coffee pot, and Bea's tea candles. All that and I'm only a quarter way through. Will make an amusing & informative read to continue later this evening

[Jeff Callahan]

Thanks for the replies, my question was not focused on mixing waxes or how long to pot pickups. It boils down to two things for me.

1. There are different grades/types of paraffin, they have a different mixture of ingredients that are made to do specific things
2. The variance of these "formulas" should create a different response to the coil's resonant peak.

A very specific and minor concern, but just thought someone out there has done the homework. I'll buy a few different types and see what the scope reads.

Paraffin Wax

Jeff

[Leo_Gnardo]

Thanks for the replies, my question was not focused on mixing waxes or how long to pot pickups. It boils down to two things for me.

1. There are different grades/types of paraffin, they have a different mixture of ingredients that are made to do specific things
2. The variance of these "formulas" should create a different response to the coil's resonant peak.

A very specific and minor concern, but just thought someone out there has done the homework. I'll buy a few different types and see what the scope reads.

Sounds like an easy enough experiment to do, and I'm sure you'll be looking at resonance before and after potting. One factor I'd like to kick in, is the measurements should be taken at a uniform temperature. One thing is certain - the DC resistance of pickup coils increases with temperature and I expect it would have an effect on resonance, not so much peak frequency, but bandwidth. Also a "control" where the coil is brought up to potting temp, not potted but cooled back to room temp, to eliminate the heat cycling as a factor. I doubt there will be any significant changes in resonance peak due to different paraffin wax types, or epoxy for that matter. But I could be wrong. I'm sure your report will get some attention here. Looking forward to it.

[Jeff Callahan]

Here's a test from a while back, just to get the ball rolling. This is the same pickup before (green) and after (blue) potting. The wax was the usual mixture of paraffin and beeswax.

Jeff

[Joe Gwinn]

Here's a test from a while back, just to get the ball rolling. This is the same pickup before (green) and after (blue) potting. The wax was the usual mixture of paraffin and beeswax.

Lowered the resonant frequency a bit (can't tell how much for lack of units on the scales). Anyway, replacing the air between turns with wax, the geometry remaining unchanged, would be expected to increase the self-capacitance of the coil a bit, which would in turn reduce the self-resonant frequency.

The dielectric constant of paraffin wax (and mineral oil) is in the range 2.1 to 2.5, for beeswax 2.7 to 3.0, and 10% beeswax in paraffin wax will be hard to tell from pure paraffin wax.

The insulation on the wire is a varnish, with a dielectric constant similar to that of the waxes. The wire datasheet usually gives the dielectric constant.

The dielectric constant of air is 1.0. The effect of replacing air with wax will vary with how tightly wound the coil is, but the self-capacitance will surely increase. Loose coils will experience a larger increase in self-capacitance, as there is more air to replace.

Dielectrics - The Physics Hypertextbook

The dielectric constant has a simple definition. Make a capacitor using air for the dielectric, and measure its capacitance. Replace the air with the dielectric of choice, and measure the capacitance again. The ratio of the capacitances is the dielectric constant (also known as the relative permittivity).

Relative permittivity - Wikipedia, the free encyclopedia

[Jeff Callahan]

Thanks Joe,

The difference in the two peaks is roughly .1KHz. I left the scale out purposely as we all know these graphs are somewhat arbitrary given everyone seems to have a slightly different approach to measuring the frequency (please not here).

My main question I guess is what type of paraffin has the lowest dielectric constant. As you mentioned Joe, tension, winding pattern, and a whole lot of other things will affect the frequency more than the type of paraffin, but none the less, why not use the paraffin with the lowest constant?

[tedmich]

FYI Museum conservation products have the widest variety waxes and oils etc available often at quite reasonable prices; they are the BEST places to formulate your own wood finishing products IME. Normally rare chemicals (or sold only by the tanker car by BASF) are available in useful amounts. Microcrystalline waxes are the most stable, predictable waxes available, and can be bought here:
Talas || Professional Archival, Bookbinding, Conservation and Restoration Supplies

not gulf wax cheap but you guys don't give away your pickups do you ?

[David Schwab]

[ATTACH=CONFIG]28755[/ATTACH]

Here's a test from a while back, just to get the ball rolling. This is the same pickup before (green) and after (blue) potting. The wax was the usual mixture of paraffin and beeswax.

Jeff

This begs the question; could you actually hear a different between the two?

I've tried different potting methods; varnish, polyurethane, cyanoacrylate, wax, and I couldn't hear any difference, both compared to each other and to an unpotted coil. Not one worth writing home about anyway.

I use regular paraffin wax now. If you are concerned with additives, get the kind used for paraffin warmers use for dipping your hand in.

[David Schwab]

My biggest complaint with bees wax is the cost, & local availability.

I buy all my supplies online. I can find the best cost and local availability is not a factor (because otherwise it's nearly zero local availability).

[tedmich]

gotta use beeswax on some pu's



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