Drilling 21/32" holes in blown-out 5/8-11 holes
 

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a "D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough. Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?

On Mon, 22 Nov 2004 19:09:56 GMT, "Tom Gardner"
wrote:

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a "D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough. Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?

Try a reamer. Not likely to grab. But ya gotta hold it straight. You
could drill and ream a 21/32 hole in a block which you clamp onto the
plate to be drilled. Then ream the hole with the block being your
guide and keeping the reamer straight.
Good Luck!
Eric

On Mon, 22 Nov 2004 19:09:56 GMT, "Tom Gardner"
calmly ranted:

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a "D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough. Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?

Tackweld a thick guide onto the plate, then ream or drill.


-- Friends Don't Let Friends Eat Turkey and Drive --

"Tom Gardner" wrote in message
.. .
I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a
"D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough.
Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?

How about a mag drill press?

On Mon, 22 Nov 2004 19:09:56 GMT, "Tom Gardner"
wrote:

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a "D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough. Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?


Four flute "Core Drill" is the best way to go. If it's a through
hole then a bridge reamer will work as well.
Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook

Gotta second Waynes advice to use a core drill. I've drilled many jet engine
mounts out for bushings w/CDs. (4340, RC 43)
For lube, castor oil is my preferance.
Thanks,
Steve Monroe

"Wayne Cook" wrote in message
...
On Mon, 22 Nov 2004 19:09:56 GMT, "Tom Gardner"
wrote:

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with a
"D"
handle 1/2" electric drill. What a bitch! I ground the bit into a spear
point on a 21/64" bit with a slight negative rake and it's still tough.
Two
guys and it still is very grabby and ary twisty. Short of a mag drill or
putting the plate on the BP (can't get it there except by mussle) There's
got to be a better way?


Four flute "Core Drill" is the best way to go. If it's a through
hole then a bridge reamer will work as well.
Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook

In article gt0pd.74555$EZ.71471@okepread07,
"Steve Monroe" wrote:

Gotta second Waynes advice to use a core drill. I've drilled many jet engine
mounts out for bushings w/CDs. (4340, RC 43)
For lube, castor oil is my preferance.
Thanks,
Steve Monroe


So _that's_ why you spend so much time in the can instead of at your
workstation. :)

WW1 pilots really did have that problem with the planes whose engines
were lubricated with castor oil from what I've read and IIRC.

^%#!! Johan! I should have seen that one coming! G
Seriously, the big advantage of castor oil is that it clings to the tool bit
so well, esp for horizontal drilling.
Regards
Steve Monroe

"Johan" wrote in message
...
In article gt0pd.74555$EZ.71471@okepread07,
"Steve Monroe" wrote:

Gotta second Waynes advice to use a core drill. I've drilled many jet
engine
mounts out for bushings w/CDs. (4340, RC 43)
For lube, castor oil is my preferance.
Thanks,
Steve Monroe


So _that's_ why you spend so much time in the can instead of at your
workstation. :)

WW1 pilots really did have that problem with the planes whose engines
were lubricated with castor oil from what I've read and IIRC.

In article G81pd.74713$EZ.67679@okepread07,
"Steve Monroe" wrote:

^%#!! Johan! I should have seen that one coming! G
Seriously, the big advantage of castor oil is that it clings to the tool bit
so well, esp for horizontal drilling.
Regards
Steve Monroe


Makes sense to me.
I'll keep it in mind for future reference.
Thanks.

Best,
John

How many holes are you drilling? Is this an ongoing project or a one-time
fix?

If you've got thousands to do there is a better way... If you have 4 to do,
then go with the quick fix for sure!

Regards,
Joe Agro, Jr.
http://www.autodrill.com
http://www.multi-spindle-heads.com

V8013


"Steve Monroe" wrote in message
news:gt0pd.74555$EZ.71471@okepread07...
Gotta second Waynes advice to use a core drill. I've drilled many jet
engine
mounts out for bushings w/CDs. (4340, RC 43)
For lube, castor oil is my preferance.
Thanks,
Steve Monroe

"Wayne Cook" wrote in message
...
On Mon, 22 Nov 2004 19:09:56 GMT, "Tom Gardner"
wrote:

I have a bunch of presses with 5/8-11 holes that are in poor shape. We
pulled the first plate, 400 lbs - 2.5" thick and started drilling with
a
"D"
handle 1/2" electric drill. What a bitch! I ground the bit into a
spear
point on a 21/64" bit with a slight negative rake and it's still tough.
Two
guys and it still is very grabby and ary twisty. Short of a mag drill
or
putting the plate on the BP (can't get it there except by mussle)
There's
got to be a better way?


Four flute "Core Drill" is the best way to go. If it's a through
hole then a bridge reamer will work as well.
Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook

I have a 21/32 reamer I don't use very often....


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