Reaming

Slow speed as well.

"Orval Fairbairn" wrote in message
news
In article ,
Fortunat1 wrote:

Another stupid question!

Been reaming holes in a few 4130 plates. The reamer worked fine for about
20 holes and then the holes started getting a bit smaller to the point
the
bolts got a bit snug.
In my ignorance I thought this one hand reamer would pretty much last me
the whole project, but it's obvious I'm going to need a half a dozen of
them at least just to do the wing hardware.
I did a bit of searching on the net and found some info on reamers. All
hand reamers seem to be HSS which would put me back in the same boat I'm
already in so I was tempted by the carbide reamers I saw for sale.
So, my question is; can you use a carbide tipped reamer designed for use
in
a lath in a simple drill press effectively? Or, for that matter, can you
use a reamer designed for use in a lathe as a hand reamer?
Or am I just barking up the wrong tree altogether?

By the way, just for info, the holes I've beenreaming are 5/16 and 1/4.
The
material is .090 4130 and the holes were all laser cut about 1/64
undersize. I would ream the first hole in each plate and then clamp
together the plates in pairs to ensure accurate alignment of the holes in
each pair of plates.
Just in case it's not the reamer's fault at all!

Did you use cutting oil? Even plain old lubricating oil helps a lot and
keeps the tool cool.

"Cy Galley" wrote

Slow speed as well.

Exactly.

If people had ever seen some charts comparing varying cutting tool speed and
feed pressure, and the resulting wear on the tool, they would be amazed.

In summary, you run your tools too fast, and they go up in smoke in a hurry.

If you ever have to guess, guess on the side of slower tool speed and more
pressure.

Of course, getting a real chart with the tool, material, and the correct
tool speed and feed speed or pressure it the "best" way to go at it. g
--
Jim in NC

"Morgans" wrote in message
...

If you ever have to guess, guess on the side of slower tool speed and more
pressure.

Amen to that, Jim. Have you ever let a drill bit spin just for a second on
some stainless and work-harden the surface?

Sounds like he is using the reamer correctly, tho. It's just the lasered
skin that's dulling the tool.

Rich S.

"Rich S." wrote

Amen to that, Jim. Have you ever let a drill bit spin just for a second on
some stainless and work-harden the surface?

My downfall is always using a large diameter bit, in a drill press that will
not go slow enough, in thick steel.

It is amazing how you can take the temper out of a 21/32" bit, in just a
couple seconds. DAMHIKT !

Also, I found you can actually get a molten blob of glass on the end of a
regular HSS drill bit. You DO have to try quite hard to do that, tho!
Especially the part of not breaking the glass, in the process. :-o

Sounds like he is using the reamer correctly, tho. It's just the lasered
skin that's dulling the tool.

I guess the answer is probably pretty obvious, but would it be possible to
normalize the steel right around the small area of the hole? Too much loss
of strength?

It does sound like lowering the tool speed would be worth the try, once the
new reamers get there. It will be fairly obvious is the tool speed is too
low, once a few holes are attempted.
--
Jim in NC

Morgans wrote:
"Cy Galley" wrote

Slow speed as well.

Exactly.

If people had ever seen some charts comparing varying cutting tool speed and
feed pressure, and the resulting wear on the tool, they would be amazed.

In summary, you run your tools too fast, and they go up in smoke in a hurry.

If you ever have to guess, guess on the side of slower tool speed and more
pressure.

Of course, getting a real chart with the tool, material, and the correct
tool speed and feed speed or pressure it the "best" way to go at it. g

Of course misidentifying metals is always a gas. Storing hardened
tool steel in the same place as free machining stainless makes for some
rather interesting experiences. Not that I have ever done it or anything

Dan, U.S. Air Force, retired

"Morgans" wrote in
:



Of course, getting a real chart with the tool, material, and the
correct tool speed and feed speed or pressure it the "best" way to
go at it. g

OK, which brings me to another side of this, I guess. I'm hand reaming. By
that I mean I'm putting a tap handle on the reamer, sticking the work piece
in a vice and going at it by twisting the thing by hand. Needless to say
it's nearly impossible to keep the reamer absolutely straight. Am I doing
this right? One suggestion I got was to use my drill press by rigging
something up to hand turn the drill spindle (no way I can get it to turn
slowly enough for reaming) in order to get the reamer straight in.

Is this unneccesarily complicated? We're talking about .090 4130 here with
a 5/16" hole. Wing attach and strut brackets for mounting onto a wooden
spar for the most part..

"Fortunat1" wrote in message
.. .

OK, which brings me to another side of this, I guess. I'm hand reaming. By
that I mean I'm putting a tap handle on the reamer, sticking the work
piece
in a vice and going at it by twisting the thing by hand. Needless to say
it's nearly impossible to keep the reamer absolutely straight. Am I doing
this right? One suggestion I got was to use my drill press by rigging
something up to hand turn the drill spindle (no way I can get it to turn
slowly enough for reaming) in order to get the reamer straight in.

If you look at the top of your hand reamer, I'll bet you'll find a centering
hole. Chuck up a tapered center in the drill press and use it to steady the
top of the reamer.

Rich S.

What's so hard about reaming? I get reamed at work every other day


Scott
http://corbenflyer.tripod.com/
Gotta Fly or Gonna Die
Building RV-4 (Super Slow Build Version)

Fortunat1 wrote:
"Morgans" wrote in
:



Of course, getting a real chart with the tool, material, and the
correct tool speed and feed speed or pressure it the "best" way to
go at it. g




--

Fortunat1 wrote:
"Morgans" wrote in
:


Of course, getting a real chart with the tool, material, and the
correct tool speed and feed speed or pressure it the "best" way to
go at it. g

OK, which brings me to another side of this, I guess. I'm hand reaming. By
that I mean I'm putting a tap handle on the reamer, sticking the work piece
in a vice and going at it by twisting the thing by hand. Needless to say
it's nearly impossible to keep the reamer absolutely straight. Am I doing
this right? One suggestion I got was to use my drill press by rigging
something up to hand turn the drill spindle (no way I can get it to turn
slowly enough for reaming) in order to get the reamer straight in.

Is this unneccesarily complicated? We're talking about .090 4130 here with
a 5/16" hole. Wing attach and strut brackets for mounting onto a wooden
spar for the most part..


You could chuck the reamer, and use the chuck key to turn it. A piece
of 1/4" rod (cut threads off long bolt) also make a nice turning handle.



--
"Life is not a journey to the grave with the intention of arriving
safely in
a pretty and well preserved body, but rather to skid in broadside,
thoroughly used up, totally worn out, with chocolate in one hand and
wine in
the other, loudly proclaiming 'WOO HOO What a Ride!'"
--Unknown

"Fortunat1" wrote in message
...
Another stupid question!

Been reaming holes in a few 4130 plates. The reamer worked fine for about
20 holes and then the holes started getting a bit smaller to the point the
bolts got a bit snug.
In my ignorance I thought this one hand reamer would pretty much last me
the whole project, but it's obvious I'm going to need a half a dozen of
them at least just to do the wing hardware.
I did a bit of searching on the net and found some info on reamers. All
hand reamers seem to be HSS which would put me back in the same boat I'm
already in so I was tempted by the carbide reamers I saw for sale.
So, my question is; can you use a carbide tipped reamer designed for use
in
a lath in a simple drill press effectively? Or, for that matter, can you
use a reamer designed for use in a lathe as a hand reamer?
Or am I just barking up the wrong tree altogether?

By the way, just for info, the holes I've beenreaming are 5/16 and 1/4.
The
material is .090 4130 and the holes were all laser cut about 1/64
undersize. I would ream the first hole in each plate and then clamp
together the plates in pairs to ensure accurate alignment of the holes in
each pair of plates.
Just in case it's not the reamer's fault at all!

Hand reamers will develop burrs on the leading edges of the cutters as you
use them. I have used a small carborundum hand stone to remove the burrs on
larger reamers, used to ream engine valve guides. Yours are smaller, so it
might be harder to find a stone small enough or with the correct geometry to
deburr them. But if you can find a stone, use it along the radial flats on
the leading edges of the cutting edges, and the reamer will be good as new
for a while.