General Inspection Query

[MJBolster]

I've been in the machining trade 25+ years and Inspection 3+. Working
with Pc-dmis 1 yr. (actually, in college, I was an art major, go figure) Any way
it has seemed at times very logical that if I measure a feature carefully, and my finding is in tolerance, that chances are that my measurement is reliable. When checking lots of 30 and above (qty) I generally record the first measurement if it's "in" and recheck several times if it's "out". This seems like nursing the data to some extent, but if you figure that there are generally a few good numbers and an infinite number of bad ones in each case, the mathematical odds at least of hitting a good number for a bad measurement favor this approach. In our receipt inspection dept. we do this all the time, in fact we'll often use a simple positional check to verify a true pos. reqmt. God knows this isn't correct but we often will play the numbers to get through the workload.
I secretly sneak around to check things correctly only to be singled out as "dragging out the process". What kinds of meatball processes have y'all
had to put up with? Do any of you use super glue to stabilize your set-ups?
(never on a surface plate I hope)
Tks for reading-
Mike

[bboyd]

I will always use a secondary measurement method to confirm my results but I will not intentionally try and make a bad number good. That said I have had to read between the lines on the GD&T to attempt to satisfy what the engineers intentions are when he/she incorrectly toleranced something. Form fit and function sometimes are the only criteria.

[rebeldude]

I do alot of "taking that point out" method. There ae other methods I am told to do I won't even discuss because of embarrassment for doing it, even though I was told to do it

[kthompson]

I haven't been in an inspection dept. working with others where I haven't seen 'shortcuts' being done to keep up with the workload. I personally don't like them, would rather be able to sleep at night (some can sleep, me if I've done something anywhere in life I KNOW to be cheating/stealing, I CANNOT sleep!) but it's almost impossible to keep up with everything required because quality is still for the most part considered an expense that doesn't improve production. (I had a shop forman at one company tell me that if he didn't have to worry about quality, he could increase production 10 times... I said "yeah, but whose gonna buy your product?")

and we use a hot-glue gun to hold parts where I work.... (can't find any aluminum magnets anywhere!)

[Mike N.]

Yeah its funny how when its a good part knowone EVER asks to recheck it

[rebeldude]

Isnt that the truth! And your right Kevin, it does make it hard to sleep at night, but this is the only die shop in the area and he knows it and uses it to his advantage

[bw_bob]

I've not been asked to outright lie but i have been told we need you and the vendor or customers numbers to correlate. Not interested if it's measured correctly.I sleep very well at night.

[Paul Sarrach]

I have sleep apnea. So I dont sleep well any night. Try sleeping with one of these.

http://www.sleepsa.com/images/cpap.jpg

[#2#]

I haven't been asked to falsify any numbers. Usually if my numbers don't agree with the suppliers' I am asked to re-measure. If there is still no agreement we usually agree to disagree and use the part if functional and ask the supplier to measure with my methods from then on (who knows if they actually do?). If the part isn't functional and to print according to supplier then I don't know as I haven't had this problem yet.

Never used superglue but I do use hot glue all the time - especially on those hard to hold plastic parts (rigid).

[T Miller]

Some of our customers send in the program to use and some of the others just come in and we get our chit together that way so we are taking the hits in the same location. It all works out in the end.. I send my boss the numbers whatever he does with them is his doing I keep backups of everything I do to cover my ***

[rebeldude]

Yes. I do make 2 different programs. One with his way and a real one. and burn them to cds

[Mike Johnston]

It's funny how I can find 80% - 90% of the dimensions on a print to be within tolerance (if I'm lucky) and those dimensions are never questioned. Only the 10% - 20% that are out of spec are "questionable" numbers. Hmmmmmmmm If it's green it must be good!

As stated previously by another member, I also have a hard time sleeping at night even when I'm told to do something "wrong". Everything is fine at the time the engineer is asking for me to find the "sweet spot" but 6 months down the road when there is a problem it seems to always be my fault.

The fact that I was asked to program a part to produce a "good" number seems to fade after just a short period of time and then they forget that they asked me to do it. Documentation is the name of the game... CYA!

Great thread by the way....

[#2#]

It's funny how I can find 80% - 90% of the dimensions on a print to be within tolerance (if I'm lucky) and those dimensions are never questioned. Only the 10% - 20% that are out of spec are "questionable" numbers.

Ha! usually with me it is 10-20% that are in tolerance. Also, with me usually the ones in tolerance are right on the nose and the ones that are out are .020-.030 out on a feature with a .005 tol.

[bw_bob]

The bottom line is "COVER THY A$$"

[Andrew Gardner]

The bottom line is "COVER THY A$$"

Absolutly -

I've told them that it takes twice as long to check a bad part than a good one.