Kenneth Scharf wrote:
7 pin mini tube sockets mount in 5/8" holes
9 pin mini tube sockets in a 3/4" hole.
Octal sockets vary, some mount in holes as small as 1", others require
1 1/8" to 1 1/4" holes.

You CAN find drills up to 1" in diameter with 1/2 shafts for use in a
drill press, but they are not cheap. I have a 1" drill that gets used
rarely.

Used Greenlee socket punches up to 1.25" (or larger) can be found on
ebay at reasonable prices. They can be cheaper than a new drill bit
of the same size!

Holes saws which have a drill bit for a pilot hole surrounded by a saw
blade bent into a circle will do a good job if the work is done on a
drill press. They cut well into aluminum or wood, but will dull
quickly into steel. Back the metal to be cut with a scrap block of
wood and clamp the work to the drill press table. Run the drill
press at a low speed (200-500 RPM) and use a little oil for
lubrication. I've cut holes up to 4" diameter into panels for meters
and CRT's with these.

You're probably using hole saws meant for wood if it dulls quickly in steel
sheet metal. You have to use bi-metal hole saws for drilling into steel.
They work quite well, and used properly, will last for quite a while.

Cheers,
Dave M



Bill M wrote:
JIMMIE wrote:
On Mar 26, 7:08 am, Bill M wrote:
Geoffrey S. Mendelson wrote:
JIMMIE wrote:
I was going to start a valve project and wanted to purchase some
hole saws for cutting out the socket holes. What sizes will I
need for 7 9 and octal sockets?
I don't remember the sizes, but holes were never sawed for tube
sockets.
Instead of using saws, which are very difficult to control and
make a mess
of everything, hole punches were used.
Punches are certainly the way to go if you have some or can borrow
some. Otherwise its kind of expensive to have to go out and buy
some for a one time use.

An alternative is the 'unibit' type of drill bits. They make them
large enough for 7/9 pin sockets. See Harbour Freight.

GL with your project.

-Bill

Ive tried the Uni-bits. They are OK as long as you don't go 1 step
too far. Unfortunately I have done that a couple of times,

Jimmie

They also have ones now that are not stepped for 'fine tuning' your
holes.

-Bill

--
David
dgminala at mediacombb dot net