Re: A new SRSG and Learning to Make Toroids-Machining Copper

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

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Parpp807-at-aol-dot-com>

In a message dated 5/30/02 7:44:30 PM Central Daylight Time, tesla-at-pupman-dot-com 
writes:

Hi Winston, All:

This may be getting a little OT but many coilers do shop work in making their 
coils.
My experience with copper machining begins (and ends) with the SRSG project.

The copper is alloy 110. The very useful McMaster-Carr catalog describes 
Alloy 110
as "20% machinable," what ever that means. Alloy 145 is listed as "80% 
machinable."
I learned that too late. The 110 alloy filled the flutes of the drill where 
it quickly seized
and busted the drill. The copper behaved as tho it were almost flowing. 
Things quickly got too hot to hold, even for a small hole. The sizes were all 
off. All the sized holes had to be enlarged. The 3/8 rod would not pass thru 
a 3/8 hole, and 7/64 was too small for
a 6-32 tap. I learned that the different alloys of copper have very different 
properties altho
it is still 99.9 to 99.99 percent pure copper. 

Cheers,
Ralph Zekelman

> Hi Mr. Zekelman, All:
>  
>   With regard to drilling copper, Machinery's Handbook says that MOST
>  copper drills similarly to steel, but likes higher tooling speeds.  Soft
>  copper should produce "small, easily broken chips" Some alloys are
>  different, and are tough to deal with.  They produce "long, stringy
>  chips".  Some cutting fluid is also recommended.  Do you know the type
>  of copper you're using? (UNS number: should be C1xxxx).  If so let us
>  know, and we'll find the exact properties of that alloy.
>  
>  Hope that helps...
>  
>  Winston
>