I need to notch some 6061 tubing for TIG welding...the diameter is
3/4" and the wall thickness is .065. I've got a drill press, so I
tried clamping the tubing to the table and tilting it to the desired
angle before attempting to notch it with a 3/4" bi-metal hole saw.
The cut is very ragged, and I'm assuming this is caused by either the
drilling speed, the lack of rigidity, or the hole saw itself. I've
got a 5 speed drill press, and it's on the slowest setting (this is
where I think it should be), and the hole saw is of the $10 variety
from Ace. Do I need to change the speed and/or the saw, or do I just
need to buy one of those jigs that attaches to my drill press, or
something else?

I suspect that your problem is not the drill, the speed, or the
hole saw. You don't have a good enough hold of the pipe.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"dan *5" wrote in message
oups.com...
I need to notch some 6061 tubing for TIG welding...the diameter
is
3/4" and the wall thickness is .065. I've got a drill press, so
I
tried clamping the tubing to the table and tilting it to the
desired
angle before attempting to notch it with a 3/4" bi-metal hole
saw.
The cut is very ragged, and I'm assuming this is caused by
either the
drilling speed, the lack of rigidity, or the hole saw itself.
I've
got a 5 speed drill press, and it's on the slowest setting (this
is
where I think it should be), and the hole saw is of the $10
variety
from Ace. Do I need to change the speed and/or the saw, or do I
just
need to buy one of those jigs that attaches to my drill press,
or
something else?

Hi Dan,
my personal experience, i bought a cheap notching jig from harbor
freight, worked crappy, got the same results you're getting. there was a
recent discussion on this topic (bruce in bangkok). i suspect (but haven't
done it yet myself, $$$) it would require a higher quality notching jig (i
don't know if this IS higher quality or if it's the same jig produced in the
same factory in china, but they say "made in u.s.a.") (and when i called
them they said they have roller bearings in the arbor)
http://www.jointjigger.com/ i also suspect it's necessary to use a hole
saw with much finer teeth than the commonly available ones. i used to have
a catalog with hole saws... just did a google search, these are the guys,
http://www.ustool.com/ they cater to the homebuilt aircraft crowd. pricy
though.

b.w.



"dan *5" wrote in message
oups.com...
I need to notch some 6061 tubing for TIG welding...the diameter is
3/4" and the wall thickness is .065. I've got a drill press, so I
tried clamping the tubing to the table and tilting it to the desired
angle before attempting to notch it with a 3/4" bi-metal hole saw.
The cut is very ragged, and I'm assuming this is caused by either the
drilling speed, the lack of rigidity, or the hole saw itself. I've
got a 5 speed drill press, and it's on the slowest setting (this is
where I think it should be), and the hole saw is of the $10 variety
from Ace. Do I need to change the speed and/or the saw, or do I just
need to buy one of those jigs that attaches to my drill press, or
something else?

On Aug 30, 3:39 pm, dan *5 wrote:
...
The cut is very ragged, and I'm assuming this is caused by either the
drilling speed, the lack of rigidity, or the hole saw itself. ...

I've used the white Home Depot hole saws on the lathe and mill, which
are much more rigid than a drill press, and also gotten a ragged cut.

jw

On Aug 30, 8:39 pm, dan *5 wrote:
I need to notch some 6061 tubing for TIG welding...the diameter is
3/4" and the wall thickness is .065. I've got a drill press, so I
tried clamping the tubing to the table and tilting it to the desired
angle before attempting to notch it with a 3/4" bi-metal hole saw.
The cut is very ragged, and I'm assuming this is caused by either the
drilling speed, the lack of rigidity, or the hole saw itself. I've
got a 5 speed drill press, and it's on the slowest setting (this is
where I think it should be), and the hole saw is of the $10 variety
from Ace. Do I need to change the speed and/or the saw, or do I just
need to buy one of those jigs that attaches to my drill press, or
something else?

Dan,
I agree whole heartidly with DanG, the problem is definately because
you don't have a good enough hold of the pipe.
There are a number of pipe vices out there that you can purchase for
very little cost. I have many and if you were a little closer, you
could have one for free, they are not expensive.
Get a pipe vice, hold it securely and you will have the problem
solved.
I hope this helps.
Best regards,
Anthony.