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Bob La Londe[_7_] Bob La Londe[_7_] is offline
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Default How Consistent Is The Ring on Taper Tooling


On 11/7/2019 2:01 PM, wrote:
Greetings Bob,
There is some variation in the flange location of regular CAT
spindles. But the tool doesn't really draw very far up into the taper
when clamped. Not enough to matter. In order to do so the socket would
need to expand and/or the tool shank would need to shrink quite a bit
and this doesn't happen. So tool setters just use a socket ground to
the tool taper and the tool is set into this socket. This socket is
either set on a tool setting fixture, or is mounted in a tool setting
fixture. And you can get a socket to set on a reference surface like a
surface plate. So you can do exactly this. I wouldn't be surprised if
you can buy one of these sockets from some outfit like MSC. If you
can't then just turn one.
Eric



So from reading that I can't (as I suspected) use the ring as a
reference. It also seems that if I want to measure off machine with a
fixture, I'll need to also use a physical tool zero mounted in a tool
holder as well. Maybe something like a gage pin in a collet chuck tool
holder.

The more I think about it though swapping tools between machines while
possible might be confusing and lead to crashes. I'd be better off to
go ahead and just duplicate tools. Probably need another dozen tool
holders eventually to cover the range of commonly used tools.

So you think just setting the tool in a socket fixture will be
repeatable enough it just won't matter? I'm not a whizz on the lathe,
but I can probably make something that will work.




On Thu, 7 Nov 2019 13:35:51 -0700, Bob La Londe
wrote:

On 11/7/2019 8:09 AM, Bob La Londe wrote:
How consistent is the ring on taper tooling?

I recently changed out the spindle on one of my small high speed
machines to an ISO20 quick change spindle. I'm trying to determine the
easiest way to measure tool length off the machine. As near as I can
tell the only purpose of the ring on ISO20 is to hang the tool

holder in
a tool changer. To do that it really doesn't have to be all that
consistent.Well not as consistent as tool length measurement needs to
be. Do I have to use an actual tool zero, and machine or buy a taper
socket to set the tools in on the surface plate?

I'm not using a tool changer. Just doing quick changes and wanting to
use the tool table to reduce time doing touch offs. Just do it once at
the beginning of the job.

So far I really like the ISO20 spindle. Its already saving me a lot of
time over the ER spindle, and I have a second one ready to go in a
second machine when I have a spare afternoon to do it.



Lets try wording this a little differently:

One of my machines uses a tool holder with a flange that actually is
pulled up against the spindle face as it is locked in the spindle. This
makes it dead easy to measure tool lengths off the machine with a height
gage. I can measure on the machine with an electronic height setter or
measure on the surface plate with a height gage and as long as
everything is cool they measure within a couple tenths. Good enough for
the work I do, and far better than the machine itself is capable of.

On another machine I never set the tool lengths because they vary beyond
the Z travel, and its just faster and easier to crank the table down and
then crank it up until the tool zeros my 2" height setter. The machine
is always machine (home) set with Z-zero at +2" work offset. Atleast in
the G54 offset. I may use other values when using additional work
offsets. Its not as fast as a tool table with a bed mill, but its fast
enough.

My main work horses have 24K spindles with until recently ER spindle
noses. I had to use the height setter after every tool change. Sometimes
quite creatively. Recently I changed one out to an ISO20 spindle. Just
being able to push pull the 5 port air valve to swap tools saves me a
lot of time already, but I want to start setting up the tool table and
using M6 G43 to apply the tool height offset just like I do on the
machine in paragraph one.

However I have a problem. I am having a hard time wrapping my mind
around how to measure the tool length off the machine. I am wondering if
its even practical. An ISO 20 does have a flange, but as near as I can
tell its only purpose is to provide a way to hang the tool in a tool
changer. From what I understand the tool is only reference by how firmly
it is pulled into the spindle taper. To me that says I can only measure
the tool length offset on the machine its being used on. Am I missing
something? I guess I could have a physical tool zero instead of using
the spindle face, and have an iso 20 ground "socket" I placed on the
surface plate to put tools in to measure. Seems to me that would result
in different measurements of the same tool just depending on how firmly
I set the tool holder in the "fixture" setting on the surface plate.

This becomes more interesting because I have a second machine I plan to
upgrade to the ISO20 quick change spindle. Already have it on hand. Just
haven't had an afternoon to spare to make the change. If possible it
would be nice to use some of the same tools on both machines. If I could
get reliable relative tool lengths off (not in the spindle) of the
machines I could just measure once, and plug the value into both
machines saving me time.

I am a one man shop who started out as a hobbyist, and now pretty much
run continuously as my primary business. Taking time now to figure out
how to save time later is a cumulative gain. Five minutes setting tool
lengths might save more time over a year then shaving 20 minutes per
part off a 50 piece order.

I sincerely would like some help, guidance, or confirmation.