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On 7 Jan 2006 04:39:09 -0800, wrote:

Hey.

There are graphic languages for welding, showing anotations on
blueprints, and languages for schematics of piping and ladder diagrams
for hydraulic, computer, pneumatic, and other fluidic logic.

Is there a graphic language for machine tools?

Two approaches, two things to express:

1) Configuration: "Set up the rotary table in the center of the mill
bed and index five slots radially."

2) Work flow: "Rough the spindle on the lathe, grind to fit the
bearing, and slot the key on the shaper."

Recent reading in KSRM (Kinetic Self-Replicating Machines) convinces me
that while it is well accepted that a serial, compact notation for
machine tool configuration and work flow would faciliate
self-replication (my specialty), I have found no such graphic language
or compact notation. We are bogged down in blueprints with unnecessary
detail distracting from the view needed for replication.

Degrees of freedom can be described readily with graphics. There's no
need to draw a blueprint of the whole machine; a lathe is "merely" a
constrained headstock with a powered rotary DOF and essential no
others, while a lathe carriage or mill ways are "merely" independent,
orthogonal, linear degrees of freedom. Graphic communication of the
existence of a stop or index in a DOF might be an arrow to a cross line
for a stop, or an arrow to a point for an index. Things like that. A
lot like the GDT symbols, but not applied to blueprints, merely
standing alone. An alchemy of machine tool potential and operation.

Things like stiffness, mass, and feed or power input might be shown in
a little matrix of low-precision numbers in suitable units.

Some combinatorics are in order, and relevant:

0 DOF: The relationship is rigid. Work in vise.

1 DOF: Must be either but not both of one rotary or one axial DOF. Ram
motion, rotary table, spindle, punch.

2 DOF: Can be either two linear, two rotary, or one linear / one
rotary. Powered spindle stroke on mill or DP, end mill flute grinder
setup, lathe carriage and cross feed, mill table, drill press cross
vise, rotary table on fourth axis tilt fixture used for machining
turbine blades.

3 DOF: Combinatorically, this can all be set down. The full potential
of all 11 coordinate systems appears here, but we'd usually think of
cylindrical, spherical, and Cartesian.

6 DOF: Item is free and unconstrained. Work in transit, and work to
which equipment or jig is fastened to guide other work, perhaps.

Maybe a little XYZ system for linear contraints, and a little cube with
circles on it for rotary contraints, or something like that. Just a
sketch language for hashing out how things are fixed and free, and how
they are powered, fed with screws or rams or a handle, and what cuts,
and what holds or guides the work. Should be applicable to everything
from molding ash quarter round on a table saw or filing the end of a
cut rod square by hand without a vise, to turbine blades and profiles
of titanium hip implants.

Doug Goncz
Replikon Research
Falls Church, VA 22044-0394
=======================
While things may have changes [and most likely have] I was always
taught that only product specific items belonged on the part
drawing. E.g. "1/4X20 2A thru" not drill w/ #7 drill and tap
with 1/4X20 2A.

It was up to the shop as to how the 1/4X20 2A was obtained.
Processing information belonged on the operation/routing sheets,
which described the order in which the operations are to be done,
special handling, the machines to be used, feeds, speeds,
fixtures, settings, special tool numbers, etc. Where a specific
type/grade of off the shelf tooling was required it should have a
tool number specified on the op sheet rather than a specific
brand name.

Stability of your product will depend greatly on the stability of
the processes, which in turn rests on the detail [and
enforcement] of the routing/op sheets. While this can be a major
PITA, it is less of a PITA than trying to track down why you can
no longer manufacture a product to spec. when you have late
orders for the same.

Complete product specifications including op sheets and routers
are required for ISO9000 and any of the major manufacturers own
quality programs such as Q1 or SPEAR.

If you can't remember what you did, it is tough to improve, or
even duplicate it.

How big is your shop [number of employees?] One indication of a
potential problem is if you depend on "Karl." A "Karl" is the
employee with a good [or lucky] memory that knows which machines
running which tools at which feeds/speeds to use for any given
job. The problem is what do you do when "Karl" is run over by a
streetcar?

Contact me off list if you would like to discuss this further.

Uncle George