[Elecraft] K2 Balun Enclosure

[EricJ]

Drilling holes in Altoids tins is easy. Use brad point bits that woodworkers
use. You can get a whole set at some place like Harbor Freight for about 6
bucks. Typically you need 3/8, 5/16 and sometimes 1/4. They are cheaper than
a step bit, and I think they work BETTER on this stuff. The center of the
bit has a sharp point that immediately digs into the soft tin preventing any
lateral movement. Then it has shoulders that scribe the circle in the metal.
Use a drill press and just enough pressure to watch the scribing action.
Soon the little hole center will just pop free. Stop there and you have an
absolutely perfect hole with no distortion of the surrounding metal. I used
to back up the bit with a chunk of wood inside the Altoids tin, but the brad
points cut so cleanly with so little pressure that it isn't even necessary
to do a back up.

BTW, brad point bits  will give you perfectly clean holes in PC board too. I
cut all the panel holes in the SW20+ shown on the same web page with them.
Perfect holes with no burrs. Just let the bit cut without forcing it.  

They are also great for cutting lands or islands on PCB for manhattan-style
construction. I just let the bit cut until it has cut through the copper.
Leaves a perfect isolated circult to solder parts to similar to the diamond
end mill that AmQRP offered for awhile. I thing they called it an Island
Cutter, in fact, but it is no longer available.

Eric
KE6US 

-----Original Message-----
From: n2fq [mailto:n2fq at sbcglobal.net] 
Sent: Monday, July 18, 2005 10:07 AM
To: EricJ
Cc: elecraft at mailman.qth.net
Subject: Re: [Elecraft] K2 Balun Enclosure

EricJ wrote:

>Not NICER, but different. I stuck mine in the traditional Altoids tin. 
>  
>
Hello..
Thanks for the correction. I did mean different.

I didn't think of removing  the terminals nor the BNC connector.
Great idea.

But must confess that I can't make a decent holes in Altoid tins. 
Probably will
invest in a step bit some day.

take care and thanks. Great photos on the other modules too, they all look
very slick.

EricJ wrote:

-- 

73
Fernando N2FQ/NNNØJYM
San Jose, CA
<http://pages.sbcglobal.net/n2fq>