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pyotr filipivich

on Wed, 08 Jul 2020 21:52:06 -0400 typed in
rec.woodworking the following:
On Wed, 08 Jul 2020 12:35:37 -0700, pyotr filipivich
wrote:
on Tue, 07 Jul 2020 20:46:41 -0400 typed in
rec.woodworking the following:
Whatever it is, so far, it hasn't interested me enough to look
into. Some people pick up software easily. not my forte.
I don't either and have to get into the head of the developer before I
can pick it up. I started with Sketchup a number of times, each time
thinking it was a CAD program. I think it was someone here who told
me to look at it from the opposite side. Draw things first, then get
the dimensions of all the parts. It's really a 3D drawing program.

So I do the drawing on paper, and port it to the program. Hmm,
maybe I can make it work.

That's nuts. Use the program for what it's designed for. 3D drawing.

that's what I said. Everything starts on the proverbial cocktail
napkin.

The advantage to CAD is revisions. I don't have to redraw the
entire plan just to move a hole an inch.
Huh? You do know the 'C' is for "computer", right?
Says so, right on my text books.
You shouldn't have to "redraw" anything to move a hole.

If you have a paper & ink drawing, revisions required the entire
thing be redrawn and re inked. Because what is on the drawing is the
legal definition of the part. I know that Boeing issues
"notifications" which are to amend / clarify a portion of a drawing,
but at one level, that is dumb. I have waded through masses of paper
to see if there is a reason why the part I have in hand, which does
not match the drawing I'm seeing, "is in spec."

So why do you do it?

It was part of the job. One of the things I have realized over
the years: when it is my part / project, the drawings can be as vague
as they want, I know what I'm trying to do. But if I want some one
else to help, make or inspect the results, then I need complete
detailed drawing.

In this case the part I have just run, does not match the
specification of the print with the work order. It is way out of
specification, and thus "scrap". (As the saying goes "You can't make
scrap fast enough to turn a profit.") Because the size specification
on the drawing was revised in an ADCN on a separate page, and possibly
_that_ was had a follow on ADCN revision of its own. You learn to
read work orders, completely.
The one which comes to mind is that the original print measured
off a beveled edge, however the ADCN showed that it was to be measured
off of a squared edge, the difference being greater than the 0.030"
tolerance. (Which is better than the parts where the spec is to where
the two angles intersect, over in the air past the curve.)

Fnord - last run of an extruded part, and the extrusion doesn't
match the drawing. Off by "that much" which is way out of tolerance.
Oy. So much for the rest of the shift.

Different issue. Sketchup would be *perfect* for designing
extrusions. Draw the cross section and pull it in the 'Z' direction.

Maybe it is.

Now, the company has gone to the effort of having several lengths
of extrusion delivered, cut to size and delivered to my work station,
along with the traveler and the program. After I run the first part
and take it in for a first part inspection, how do I shrink the
extrusion to fit the PCM of the part? Remember, this is the
customer's life sized drawing of how the part is to be, the company
has bought the extrusion, and I'm one of a dozen operations on this
part. My part of the job went perfect, but the extrusion web was too
"tall". When lined up and laid on the PCM, the bottom of the one leg
was just a tad above where the top was suppose to be: the web was
excessive by the thickness of the leg. Once I pointed that issue to
the foreman, I was done. Stop, halt, go no further, make no more
parts. "Edinburgh, we have a wee problem".
There was a guy who could just change the specification of the
part, but that was not me.

tschus
pyotr

--
pyotr
Go not to the Net for answers, for it will tell you Yes and no. And
you are a bloody fool, only an ignorant cretin would even ask the
question, forty two, 47, the second door, and how many blonde lawyers
does it take to change a lightbulb.