Re: Tungsten "bullets"

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi All,

I think these inserts are used on REAL drill bits :-))

http://www.mining-technology-dot-com/contractors/drilling/sandvik/sandvik4.html

http://www.torquato-dot-com/acc.html
(check about 70% down the page :-)))

http://www.torquato-dot-com/express.html

Make your own...
http://www.torquato-dot-com/gcups.html 

Cheers,

	Terry


At 10:57 AM 8/17/2001 -0400, you wrote:
>
>
>Tesla list wrote:
>> 
>> Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>
>> 
>> Hi Scott,
>> 
>> They are very nice :-))  I assume they are used for machining, probably
>> alighnment as you say.  They are 0.3140 inchs in diameter but I will defeer
>> to Marc for the full story...  They seem very nicely shaped for spark gap 
>uses!
>> 
>> Cheers,
>> 
>>         Terry
>> 
>> At 06:14 PM 8/16/2001 -0700, you wrote:
>> >Terry -
>> >
>> >I have pounds of the tungsten carbide disks like in your photo (actually
>> >cutting-tool inserts), but I have never seen the "bullets".
>> >
>> >They look like they are locating pins (dowel pins) for aligning tooling
>> >components.
>> >
>> >Do you know exactly what they are, and the source?
>> >
>> >Were these found by Marc Metlicka?
>
>Yes
>These were in a big bag at my local surplus "doodads are us" store along
>with all the carbide inserts and cutters. I asked what they actually
>were and they told me that they came from the caterpillar factory so I'm
>assuming they are detents for transmissions or hydraulic control valves?
>they have a beautifully continuous conical taper to the tip and stand up
>very, very well in gap use.
>i wanted to buy the remaining 200 or so (they sell all carbide for
>$10.00 a pound to me) but i missed out before they started moving to the
>new building, everything was sold for scrap?
>so much for the plan of offering them to the list.
>when they get settled into the new digs, i will be checking for inserts
>to offer the list.
>I have logged many hours of gap time on carbide and have yet seen one
>that shows any sign of wear or corrosion? even the little 1/4" carbide
>inserts (like i sent terry) that i brazed onto 1/4" brass rod, have
>stood up very well. I haven't noticed any "ill effects" from the lower
>conductivity, but i can say that nitride coated carbide DOES NOT WORK in
>gap use, It gives an arcing that "looks" like there is no tank capacitor
>connected, a very strange effect?
>Take care,
>Marc M.
>geek #1055
>PI geek
>http://www.thegeekgroup-dot-org/
>
>
>
>> >
>> >Thanks!
>> >Scott
>> >
>