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Default out of position vertical mill

I've got a question (or a few) for the experienced machinists who
generously contribute so much to this group.

At my school there are two machine shops. The kind machinists once
told me about the versatility of the vertical mills. They explained
how the upper components can swivel, turn and be repositioned. The
ram? it appears can be moved 90 degrees away from the table off to the
side or behind the mill, and the head can be pivoted into compound
angles.

My question(s): Does anyone ever actually use these non-standard
positions for the mill? Doesn't the rigidity get lost at such long
lever arm lengths away from the table? Anybody got some pictures? What
is actully worked on in these settings? How is it mounted? This stems
from concluding you can't put a v-8 350 block on the table of a small
mill and work on it.

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Robin S.
 
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wrote in message
oups.com...

My question(s): Does anyone ever actually use these non-standard
positions for the mill?


While I've seen it done, I've never had occation to do it myself.

Doesn't the rigidity get lost at such long
lever arm lengths away from the table?


Knee mills of this type aren't very sturdy anyway, no matter how close the
head is to the base/turret. There are too many joints between the cutter and
the table. It's pretty easy to run such a machine so hard as to knock it out
of square. This is agravating, but then there are always comprimises.

Quills are nice, but they also cause instability as well. Mills without
quills are very capable of ripping down blocks, but they are virtually
incapable of drilling a hole.

Regards,

Robin


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Harold & Susan Vordos
 
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wrote in message
oups.com...
I've got a question (or a few) for the experienced machinists who
generously contribute so much to this group.

At my school there are two machine shops. The kind machinists once
told me about the versatility of the vertical mills. They explained
how the upper components can swivel, turn and be repositioned. The
ram? it appears can be moved 90 degrees away from the table off to the
side or behind the mill, and the head can be pivoted into compound
angles.

My question(s): Does anyone ever actually use these non-standard
positions for the mill? Doesn't the rigidity get lost at such long
lever arm lengths away from the table? Anybody got some pictures? What
is actully worked on in these settings? How is it mounted? This stems
from concluding you can't put a v-8 350 block on the table of a small
mill and work on it.


Yep! Those amongst us that have such machines do, on occasion, take
advantage of their capabilities. Mind you, the vast majority of use such
machines get is in the right angle position, but there's nothing quite like
having the capability to rotate the turret, advance the ram, or tilt the
head in two directions when a particular job calls for any of those
features.

Without a specific case at hand, it's difficult to explain how valuable they
can be. One that readily comes to mind could be that you have a long
piece, somewhat longer than the table travel. You prefer to not reposition
the piece, for reasons best known to you. What you do is set it up on the
table to your convenience, then rotate the turret such that you can machine
the entire piece in two steps. The first step cuts one end of the part,
the second step the other, after repositioning the turret. That
necessitates reorienting the spindle to the part, but it does prevent
setting up the part a second time, which in some cases can be good.

You do give up a small amount of rigidity in machines like a Bridgeport. If
you've ever run a Gorton Mastermil, for example, you'd readily see that the
Bridgeport is quite light duty by contrast. All of that can not be
attributed to the flexibility of the Bridgeport, however. A Mastermil
outweighs a Bridgeport considerably.

The benefits of a flexible machine like a Bridgeport outweigh any of the
negatives tremendously. Aside from the purchase price of Bridgeport
mills, which used to be very reasonable, it was the secret to their success.

Harold


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Jon Elson
 
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wrote:
I've got a question (or a few) for the experienced machinists who
generously contribute so much to this group.

At my school there are two machine shops. The kind machinists once
told me about the versatility of the vertical mills. They explained
how the upper components can swivel, turn and be repositioned. The
ram? it appears can be moved 90 degrees away from the table off to the
side or behind the mill, and the head can be pivoted into compound
angles.

My question(s): Does anyone ever actually use these non-standard
positions for the mill? Doesn't the rigidity get lost at such long
lever arm lengths away from the table? Anybody got some pictures? What
is actully worked on in these settings? How is it mounted? This stems
from concluding you can't put a v-8 350 block on the table of a small
mill and work on it.


Sure. The more extreme the position, of course, the less rigid the
machine is. But, there are times when you just can't do some setup
with the spindle vertical. Generally, taking shallower cuts at lighter
feed rates can compensate for the reduced rigidity.

I think a LOT of this sort of work is now done on CNC machines
without altering the mill's basic setup. Also, in many cases,
multi-side access and multi-axis machining can be done with one
or two rotary indexers holding the workpiece. Moving the workpiece
this way leads to much more predictable positioning than trying to
loosen and swing various pivots on a Bridgeport-syle machine, and then
pick up the coordinate references. But, you certainly can't position
a big-block V8 very well even on a Series-II Bridgeport. Heads might
be done on a benchtop mill, but the block requires a pretty big work
envelope if you are going to machine all over the block. If you
need to plane the deck, that might not be too bad.

Jon

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Grant Erwin
 
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I swivel the head on my Bridgeport fairly often to machine angles.

Here is an extreme example: you have a round piece of 8" billet stock
steel 30" long. You hump it up on your mill table on 2 herkin V-blocks
and get it straight and clamped down. Now you have to mill a deep V
in *one end*. What you do is, you slew the ram around to about 45°,
extend it way out, put on the BP right angle head, dial in the head
so its axis is parallel to the workpiece, put in your V cutter and
use your Y feed to mill the vee on the end. - GWE

wrote:
I've got a question (or a few) for the experienced machinists who
generously contribute so much to this group.

At my school there are two machine shops. The kind machinists once
told me about the versatility of the vertical mills. They explained
how the upper components can swivel, turn and be repositioned. The
ram? it appears can be moved 90 degrees away from the table off to the
side or behind the mill, and the head can be pivoted into compound
angles.

My question(s): Does anyone ever actually use these non-standard
positions for the mill? Doesn't the rigidity get lost at such long
lever arm lengths away from the table? Anybody got some pictures? What
is actully worked on in these settings? How is it mounted? This stems
from concluding you can't put a v-8 350 block on the table of a small
mill and work on it.



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Robert Nichols
 
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In article .com,
wrote:
:I've got a question (or a few) for the experienced machinists who
:generously contribute so much to this group.
:
:At my school there are two machine shops. The kind machinists once
:told me about the versatility of the vertical mills. They explained
:how the upper components can swivel, turn and be repositioned. The
:ram? it appears can be moved 90 degrees away from the table off to the
:side or behind the mill, and the head can be pivoted into compound
:angles.
:
:My question(s): Does anyone ever actually use these non-standard
ositions for the mill? Doesn't the rigidity get lost at such long
:lever arm lengths away from the table? Anybody got some pictures? What
:is actully worked on in these settings? How is it mounted? This stems
:from concluding you can't put a v-8 350 block on the table of a small
:mill and work on it.

Not an engine block, but I once had the base casting for my "$200"
bandsaw mounted on the table of my little Clausing 8520 mill so that I
could re-bore the pivot holes. The mill's ram was pivoted 90 deg and
the head tilted 90 deg so that the quill was horizontal and pointed
directly toward the front of the machine. Looked ridiculous to see that
casting up there on the table, but it worked just fine. The lever arms
in that position aren't any longer than normal, just oriented
differently.

It's not the sort of capability you use often, but when you need it, you
_really_ need it. Simple tilting of the head is a lot more common.

--
Bob Nichols AT comcast.net I am "rnichols42"
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Richard W.
 
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"Robin S." wrote in message
...

Mills without quills are very capable of ripping down blocks, but they are
virtually incapable of drilling a hole.


Not true, I think you need to think about this some more.


  #9   Report Post  
Robin S.
 
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"Richard W." wrote in message
...

Not true, I think you need to think about this some more.


Try and charge $65/hr while cranking the knee to drill a hole.

Regards,

Robin


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john
 
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"Robin S." wrote:

wrote in message
oups.com...

My question(s): Does anyone ever actually use these non-standard
positions for the mill?


While I've seen it done, I've never had occation to do it myself.

Doesn't the rigidity get lost at such long
lever arm lengths away from the table?


Knee mills of this type aren't very sturdy anyway, no matter how close the
head is to the base/turret. There are too many joints between the cutter and
the table. It's pretty easy to run such a machine so hard as to knock it out
of square. This is agravating, but then there are always comprimises.

Quills are nice, but they also cause instability as well. Mills without
quills are very capable of ripping down blocks, but they are virtually
incapable of drilling a hole.

Regards,

Robin




only cant drill "out of position holes" or holes not parallel the
spindle c/l


John.


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Richard W.
 
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"Robin S." wrote in message
.. .

"Richard W." wrote in message
...

Not true, I think you need to think about this some more.


Try and charge $65/hr while cranking the knee to drill a hole.


The machines with fixed spindles that I have seen had #40 or #50 tapers,
they also have power feed built in. I have drilled 1 1/2" diameter holes
with them for hydraulic valves and then bored them.

Richard W.


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Robin S.
 
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"Richard W." wrote in message
...

The machines with fixed spindles that I have seen had #40 or #50 tapers,
they also have power feed built in. I have drilled 1 1/2" diameter holes
with them for hydraulic valves and then bored them.


You're right about larger holes. As long as you have a good selection of
feeds available, those machines would ideal for holes that are difficult to
push by hand (assuming the machine has adequate Z clearance)

Regards,

Robin


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