larry g wrote:

I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA
lg
no neat sig line





If you've got a four jaw chuck for the lathe that's what I would use.

In article , larry g says...

I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA

I would do this job on the lathe if the positioning accuracy for
the hole were not a big issue. The two techniques will
both produce holes of equal finish and diameter accuracy.

Unless I had to get the hole to be at some particular
location with respect to an edge of the block I would put
the part in the four jaw chuck and do it that way.

Jim

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"tomcas" wrote in message
...
larry g wrote:

I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block.
I
have a Logan 10" lathe and a small Index mill with power feed on the
quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA
lg
no neat sig line





If you've got a four jaw chuck for the lathe that's what I would use.
Or a face plate...either will work

In article ,
larry g wrote:
I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA

Hmm ... do you have a 4-jaw chuck for the lathe? I presume that
you're going through the block the long way. How long is the spindle
travel on the mill? If it is shorter than the length of the bore (3"
here, I presume), then the lathe is probably the better choice, if you
have the 4-jaw. You *could* do it by cranking the knee up. (The index
mill does have a knee, doesn't it?)

Lacking discovering that some limitation will make it more
difficult on one of the tools (e.g. quill travel on the mill), use
whichever machine you're more comfortable with if the job is important
and you don't have spare stock. Otherwise, you might consider it a
learning experience on the other machine.

Personally, I would probably use the lathe, but that is just
personal preference.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
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On 3 Sep 2003 22:26:22 -0400, (DoN. Nichols)
wrote:

In article ,
larry g wrote:
I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA

Hmm ... do you have a 4-jaw chuck for the lathe? I presume that
you're going through the block the long way. How long is the spindle
travel on the mill? If it is shorter than the length of the bore (3"
here, I presume), then the lathe is probably the better choice, if you
have the 4-jaw. You *could* do it by cranking the knee up. (The index
mill does have a knee, doesn't it?)

Lacking discovering that some limitation will make it more
difficult on one of the tools (e.g. quill travel on the mill), use
whichever machine you're more comfortable with if the job is important
and you don't have spare stock. Otherwise, you might consider it a
learning experience on the other machine.

Personally, I would probably use the lathe, but that is just
personal preference.

Good Luck,
DoN.

And Im just the opposite. Id use the mill, as its faster to setup and
center. Shrug

Gunner

"War is an ugly thing, but not the ugliest of things. The decayed and degraded state of moral and patriotic feeling
which thinks that nothing is worth war is much worse. The person who has nothing for which he is willing to fight,
nothing which is more important than his own personal safety, is a miserable creature and has no chance of being
free unless made and kept so by the exertions of better men than himself."
- John Stewart Mill

"Gunner" wrote in message
...
On 3 Sep 2003 22:26:22 -0400, (DoN. Nichols)
wrote:

Personally, I would probably use the lathe, but that is just
personal preference.

Good Luck,
DoN.

And Im just the opposite. Id use the mill, as its faster to setup and
center. Shrug

Gunner

As would I. Setting up in a lathe to bore a square item is rarely as easy
as on a mill. What better way to improve your ability on the mill than
you use it? Getting the bore perpendicular and dead centered, if a
requirement, is so much easier in the mill. Holding size is no issue,
either.

Harold

Subject: Boring, Lathe or Mill?
From: "larry g"
Date: 04/09/03 01:02 GMT Daylight Time
Message-id:

I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA
lg
no neat sig line

There's a simple rule. Given the choice you always do one off work on the
machine that has adjustment built in to the machine and not the cutting tool.
So boring is a lathe job not a milling job.


Dave Baker - Puma Race Engines (www.pumaracing.co.uk)
I'm not at all sure why women like men. We're argumentative, childish,
unsociable and extremely unappealing naked. I'm quite grateful they do though.

larry g wrote:

Thanks to everyone.
Ok then, it sounds like a unanimous on the lathe. Glad I asked cuz I think
I would have used the mill. I will be going through the block, 2" through,
and the location is not critical, but the size is as well as being
perpendicular to the face.


Make sure you take a skim cut on the face while you are in the same
setup to insure perpedicularity.

larry g wrote:

I have an upcoming need to bore a 1.125" hole in a 2x2x3" brass block. I
have a Logan 10" lathe and a small Index mill with power feed on the quill.
My question is which machine would I expect to do the job with greatest
accuracy? I have a Criterion type boring head for the mill and proper
boring tools for the lathe. TIA
lg
no neat sig line




I like to use the biggest boring bar that will fit. In this case it
would probably be on
your lathe. In addition, since it will be boring horizontally, chip
control is easier and
the compound slide can be set at an angle to provide 0.0001 adjustments.

Fred

Make sure you take a skim cut on the face while you are in the same
setup to insure perpedicularity.

a skim cut will not insure perpindictularity.

best way to get perpindictularity is to indicate the top of the block prior to
grinding. 0 it out on all 4 corners while spinning the spindle

"Wwj2110" wrote in message
...
Make sure you take a skim cut on the face while you are in the same
setup to insure perpedicularity.

a skim cut will not insure perpindictularity.

best way to get perpindictularity is to indicate the top of the block
prior to
grinding. 0 it out on all 4 corners while spinning the spindle

A skim cut will insure perpendicularity if done while the block is still set
up in a 4 jaw chuck, but the face may or may not be at right angles to the
bore, though still perpendicular, based on the concept that if the
particular lathe has any angular cross slide error, the face can taper.

Indicating existing corners does not guarantee that a bore will be
perpendicular unless the face had been cut after the bore was finished, all
in the same set up. That's what the poster said, and he's right.

Harold

A skim cut will insure perpendicularity if done while the block is still set
up in a 4 jaw chuck, but the face may or may not be at right angles to the
bore, though still perpendicular, based on the concept that if the
particular lathe has any angular cross slide error, the face can taper.

Indicating existing corners does not guarantee that a bore will be
perpendicular unless the face had been cut after the bore was finished, all
in the same set up. That's what the poster said, and he's right.

Harold


I stand corrected. I was in the mill & he was on the lathe.