Tesla's "COIL FOR ELECTRO-MAGNETS".

[synchro1]

At 14 seconds into this video, freeze frame, and You'll see a picture of an industrial "Tesla Scrap Yard Magnet" from 1914. What strikes you as peculiar about this photo? The wire's kinda small?

http://www.youtube.com/watch?v=gfJG4M4wi1o

[gyulasun]

I'm not setup to make those kinds of measurements. A pico second pulse is all it takes to bring all the electron spins into alignment and permenently magnatize the iron ferrite. A permanent magnet is free energy compared to electromagnetic field. The SBC nail permenently magnetizes from the high voltage field collapse spike, and needs no further current. The permanent field is twice what the single wire electromagnet produces under power. Have you seen my Cook battery post above?.

Of course I did not mean picosecond accuracy but you hit the nail on its head: when you magnetized your nails, how did you keep magnetization time for them to be nearly identical? Even if we assume the nails had a nearly identical magnetic permeability (which is also a question)  in case the ON time for your input power to the coils was not a repeatable process with good accuracy then your nails got magnetization at a different degree which can easily explain the difference in strength between them.
You still did not answer your battery voltage used. Why?

[synchro1]

Of course I did not mean picosecond accuracy but you hit the nail on its head: when you magnetized your nails, how did you keep magnetization time for them to be nearly identical? Even if we assume the nails had a nearly identical magnetic permeability (which is also a question)  in case the ON time for your input power to the coils was not a repeatable process with good accuracy then your nails got magnetization at a different degree which can easily explain the difference in strength between them.
You still did not answer your battery voltage used. Why?

I used a 12 volt battery to them both. The SBC generates a much larger spark. Did you catch the photgraph of the old fashioned Tesla type sctap yard magnet? What do you notice funny about it?

[gyulasun]

I used a 12 volt battery to them both. The SBC generates a much larger spark. Did you catch the photgraph of the old fashioned Tesla type sctap yard magnet? What do you notice funny about it?

Yes I watched it and you surely mean the wires feeding the electromagnet seems not to be thick right?  Well we do not know how much lifting power the electromagnet was originally designed for?
You always mention the scrap yard electromagnet: have you seen the winding style inside? I bet you will say it was made from bifilarly wound windings...  but please understand that only a comparison test to an identical input power single coil electromagnet should decide their performance, (wire lengths should be the same for both).

[picowatt]

At 14 seconds into this video, freeze frame, and You'll see a picture of an industrial "Tesla Scrap Yard Magnet" from 1914. What strikes you as peculiar about this photo? The wire's kinda small?

http://www.youtube.com/watch?v=gfJG4M4wi1o

Synchro1,

What makes you believe the picture labeled "industrial electromagnet" is a "Tesla Scrap Yard Magnet"?

Same picture and construction details for a similar lifter are given here:

http://en.wikipedia.org/wiki/Electromagnet

Small wire?  Lots of turns (i.e., ampere-turns) ... 

They may have used lots of turns of potted wire in 1914 (as opposed to the copper or aluminum strips indicated in the Wiki).  Higher voltage, less amps, smaller wire.

PW