The problem of the Too Solid Goof. Thanks boss.

Greetings and salutatorians

The problem of the "Too solid goof" is when you know you have a
problem, but you know it can't be in 'that' part of it, it must be
somewhere else. Often enough, it is the section which is Too Solid (you
know it is correct) where the problem lays. Like the noisy engine valves
was because the rocker arm nuts weren't tight, which you discover _after_
you get the engine removed from the vehicle. Or in this case, why the
parts were getting boogered up pretty bad.

It has been a loverly day or two at the old mill. I'm making Aluminum
brackets from L extrusions (arrow space). Two vice operation, in vice one
we cut the hole for the whatever, and drill two holes for that mounting,
remove part, place in vice two and cut the bottom legs (and drill their
pilots holes). Makes two parts per piece of stock. Neat.
When it works. Oh yes, this is "Run 2" - second time this program has
been run, so I'm the Beta test. The First Run guys, they're Smart
Experienced Machinists. I'm just starting out, gaining that Good Judgment
which comes from Experience. (and we all know where experience comes from.)
So 'yesterday', oh thit do we scrap a bunch of parts. (five out of
thirty two.) But I and the Shift Super do figure out a source of the
problem: too fast a feed at one point is pulling the parts up and out of
the fixture. (also discover that there is a rapid traverse from the end of
the cut in station one to the start of station two, of the form "N2 G0 G55
X10.00" - yes, no Y value. Stick the Y value in to make it easier to pick
up the program in the middle.)
Anyway, get that all done, deburred, and then set up the next part.
Similar layout, but wider. Turn in the First Part for inspection promptly
at 0259, write up the tie in, and go home. Come back this 'morning' and I
get told to do something else while they jigger with the program.
(Deburring the parts of Doom.)
So after break, "It's good to go." Yeeha! I fire it up, and it makes
its two little holes, and then goes to rough the outline and "clank!" "That
didn't sound good!" Shut off spindle and coolant (can't see a thing
through the coolant.) "Say - where did the 3/8" bit go?" Start laughing.
"I broke the tool!" (You must understand, earlier in the day, a co-worker
made an error, and scrapped six parts, then repeated the same error and
scrapped another. But the crowning glory was he held the scrap piece in
his hand while spraying it with red Dye-kem. Got the scrap parts too.)
I'm just in too good a mood for things to go wrong and me to be bummed out
by it.
Over to tool crib in other building and ask if he can put a new flute
on the broken part, and then stick it back together. He laughs too. Sets
up a new tool, which the high priced Zoler says is .3785 radius, but the
micrometer says is .375 inch. Go with the high price opinion. Install,
change the TLO, start over. This helps, new tools are sharper. But it still
pulls one part out of the vice. Call supervisor, consult, we all most save
the part. (got a mismatch of surfaces exceeding tolerance by a butload.
We didn't measure, so I don't know if it was a metric or standard
buttload.) He advises that I "saw off the excess before making the rough
cut". This works, even if I am adding a couple minutes to the cycle time
walking over to the bandsaw (the nearby one has a short in the powercord
and is Out of Service). But something is still not right. "Say, what is
this on the screen?" Why does it say 'spindle override: 50%'?" Hmmm - I
consider calling the supervisor, but decide "Take some initiative. Crank
it way up, yeah, all the way to 100%!" Great improvement, and continue
sawing the excess off until the supervisor wanders back over. I ask him
about how the spindle over ride might have gotten changed. "Oops, I
changed it during the dry run and forgot to turn it back." Yee-haw! WTH,
don't need to bandsaw the excess, but the program still needs those other
changes. Cut the last three pieces of stock in "record time."

So, once again, the word to the wise is: even if they've been doing a
lot longer than you have, check everything. Especially if they're suppose
to know what they are doing.

Well, it is now long past my bed time, I'm burning daylight. The good
news is that we made it through the week without layoffs. On the other
hand, we still have four fingers and a thumb.

good night and sleep tight.
pyotr




--
pyotr filipivich.
"I wish you wouldn't use the mind control device - I get
these terrible migranes until it's finished." Jonathon
.

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