I was not really planning on going into work next week, but this has

changed my mind.

http://gilmore.chem....n.edu/ebony.jpg

1500 grams, 8 x 2.5 x 3.5 inches

about 50 years old.

that's a big black log.

For a new pair of Grados? <<chuckle chuckle>>

Yeah we know that you are good at doing knobs...

Might it be for sumpin else?

Is that real gaboon ebony (Diospyros crassiflora?) That must have set you back quite a bit.

That would yield a good number of frogs...

Is that real gaboon ebony (Diospyros crassiflora?) That must have set you back quite a bit.

Yep, the real stuff, and aged about 50 years. Tree had to be a couple hundred

years old. Its very hard to find a piece big enough to make knobs out of.

Yes i got clobbered both on the price, and on shipping.

You just don't see pieces of gaboon ebony like that these days.

http://gilmore.chem.....edu/ebony2.jpg

http://gilmore.chem.....edu/ebony3.jpg

http://gilmore.chem.....edu/ebony4.jpg

i managed to find a bullseye again.Too bad its so

hard to see. And also a defect inside the wood.

Its rough cut, ready for micro machining

Edited December 27, 201114 yr by kevin gilmore

That looks beautiful

Can't wait to see the final result.

real men use Beryllium, and laugh at the toxicity as they mutate........

I have a 7 lb chunk of pure berryllium in my drawer at work that i was thinking

of turning into a knob. I have already been told that i will not be allowed to

use the machines at work to do this. And i'm not stupid enough to try

this on my lathe at home.

Berryllium not so bad. Berryllium Oxide, very VERY bad.

I also have about 25 lbs of mercury, not sure what to do with that either.

Maybe waterford crystal knob filled with mercury might be neat.

There are a number of kinds of stainless steel. The screws i have are

non-magnetic. All my NMR magnets are made of non-magnetic stainless.

I do remember the NS100's. Good speakers, a little bright. Very yamaha sound.

Edited January 1, 201214 yr by kevin gilmore

Mercury? Make a cryo chamber for the electronics and use a solidified mercury knob. Just cosmetic use, but very very cool

We used to have a 1kilowatt amplifier that we tested wattmeters with that had Beryllium oxide inside as part of the heatsink compound formula.

Wikipedia.

Beryllium oxide (BeO), also known as beryllia, is an inorganic compound with the formula BeO. This colourless solid is a notable electrical insulator with a higher thermal conductivity than any other non-metal except diamond, and actually exceeds that of some metals.^[2] As an amorphous solid, beryllium oxide is white. Its high melting point leads to its use as a refractory.^[3] It occurs in nature as the mineral bromellite. Historically and in materials science, beryllium oxide was called glucina or glucinium oxide.

Like all beryllium compounds, BeO is carcinogenic and may cause chronic beryllium disease. Once fired into solid form, it is safe to handle as long as it is not subjected to any machining that generates dust.^[8] Beryllium oxide ceramic is not a hazardous waste under Federal law in the USA.

Depleted uranium makes nice knobs. Hefty feel. Be sure to use beryllium copper tools though, don't want sparking.

Uranium makes sparks when struck / scratched / tapped just right with a steel tool, and the sparks are burning uranium metal- and while the uranium is mostly depleted of radioactive isotopes it is not FREE of them, and inhaling a little u-235 oxide vapor / dust is a bad thing, strong alpha emitter....induces lung cancer...

What's the fun in THAT?

I say let the chips and sparks fly!

While you are at it, pass me the lead paint chips and dip.

Asbestos popcorn ceiling scrapings sound yummy too!

micromachining revealed cracks and roughness, will have to machine up more wood.

http://gilmore.chem.northwestern.edu/ebony5.jpg

http://gilmore.chem.northwestern.edu/ebony6.jpg

http://gilmore.chem.northwestern.edu/ebony7.jpg

Edited January 7, 201214 yr by kevin gilmore

that's easy enough to fix, just mill it in a reducing atmosphere. i hear Mercury is nice, this time of year.

Hehehe, I had missed this comment

Sorry for those unacceptable ebony knobs, you may send them to me if you wish. I'd pay the shipping

Ooh, that's so f'in' nice Kevin!

If you have one left over, and you decide to sell it...

[swt61] ... then send it to Marc. It's close enough that I could make conjugal visits.[/swt61]

Noted the flaw in the second pic at just below 3 o'clock.

That's a conversation starter. Something for the nosy pedants to pontificate about........

Shame about the crack, but I agree it looks f'in awesome

I have enough wood for 5 more. Should have the 2nd one done tuesday or wednesday.

Wow, for such a big piece of wood, it's only good for 6 piece of knob?

That hairline crack is not problematic. It will not enlarge or separate in time. If it's just an aesthetic issue, then by all means let me fix it. A burn in will make it near undetectable under a magnifying glass.