Number of Quality Control personnel vs Machinists
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 34
  1. #1
    Join Date
    Oct 2011
    Location
    Champaign, Illinois
    Posts
    30
    Post Thanks / Like
    Likes (Given)
    13
    Likes (Received)
    8

    Default Number of Quality Control personnel vs Machinists

    Just curious how many Quality people you guys have vs how many guys are making parts.

    We have about 25 guys making parts during the day,2-3 robots loading mills at night, and gobs of live tool lathes and swiss machines, with 2 guys trying to check everything.

    It is regularly a bottle neck and I'm just curious how far off the mark we are. I know it depends a lot on what work you're doing. Well we do a little of everything, with an increasing stake in Aerospace and Defense contracts, all the while working on ISO certification. I know we need at least one more guy but I even question if that is enough.

    Again, I'm just curious what others are doing and other opinions.

    Thanks in advance.

  2. #2
    Join Date
    Feb 2013
    Location
    Madison, WI
    Posts
    951
    Post Thanks / Like
    Likes (Given)
    1092
    Likes (Received)
    610

    Default

    Are these just first piece inspections, or are they also supposed to do all in process inspections? How many setups do you average per day? How complicated are the parts? How long is your average production run?

  3. Likes Dualkit, Gordon B. Clarke liked this post
  4. #3
    Join Date
    Feb 2005
    Location
    Akron, OH
    Posts
    1,822
    Post Thanks / Like
    Likes (Given)
    277
    Likes (Received)
    1367

    Default

    Also how complicated are their inspections? One diameter with calipers or 800 points with a manual CMM?

    If they're working efficiently and they're the bottleneck, then add another one. Who cares what other people are doing? 25:3 doesn't sound unreasonable at all. For whatever it's worth, our ratio is 6:1

  5. Likes hanermo liked this post
  6. #4
    Join Date
    May 2017
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    927
    Post Thanks / Like
    Likes (Given)
    1093
    Likes (Received)
    568

    Default

    Are they doing everything manually or do you have a CMM / vision system?

  7. #5
    Join Date
    Sep 2009
    Location
    barcelona, spain
    Posts
    2,366
    Post Thanks / Like
    Likes (Given)
    525
    Likes (Received)
    1421

    Default

    You stuff sounds like high end work --
    but may mean nothing.

    In-machine probing might qualify 99% of the parts, or features, .. or not.

    Endless ways exist to improve stuff - sometimes vastly, depending on what is being measured and qualified.

    E.
    A ring gage on a cnc with touch probes, might prove outer D and some other critical features, fast.
    Cylindricity, roundness, surface finish would not likely be qualified. Nor tir.

  8. #6
    Join Date
    Jan 2007
    Location
    Flushing/Flint, Michigan
    Posts
    7,581
    Post Thanks / Like
    Likes (Given)
    377
    Likes (Received)
    6331

    Default

    Quote Originally Posted by Comatose View Post
    Also how complicated are their inspections? One diameter with calipers or 800 points with a manual CMM?

    If they're working efficiently and they're the bottleneck, then add another one. Who cares what other people are doing? 25:3 doesn't sound unreasonable at all. For whatever it's worth, our ratio is 6:1
    So in a 600 man shop you would have 100 inspectors?
    Bob

  9. #7
    Join Date
    Jan 2003
    Location
    Canada
    Posts
    11,175
    Post Thanks / Like
    Likes (Given)
    5213
    Likes (Received)
    3315

    Default

    Well, if you're getting NCR's from customers, definitely up the quality control.
    If everyone's happy with the quality and almost never anything coming back, I guess it ain't too bad.
    2 final inspectors for a 25-30man shop seems average. Ideally the parts should be good before they get to them...
    See if there's any inspection equipment you can add to make it faster/easier.

  10. #8
    Join Date
    Feb 2005
    Location
    Akron, OH
    Posts
    1,822
    Post Thanks / Like
    Likes (Given)
    277
    Likes (Received)
    1367

    Default

    Quote Originally Posted by CarbideBob View Post
    So in a 600 man shop you would have 100 inspectors?
    Bob
    No, literally it is 6 operators to one inspector here. But for a 600 person shop, if they were doing all one-offs with 100% inspection? Maybe!

  11. #9
    Join Date
    Mar 2011
    Country
    SWITZERLAND
    Posts
    990
    Post Thanks / Like
    Likes (Given)
    119
    Likes (Received)
    401

    Default

    Better hire better machinists. The ideal would be that the makers make good parts in the first place. It’s the old-time approach, check everything that goes in 100 percent, then nothing bad comes out. The contrary is chaotic manufacture and completely overburdened QM.

    Material, workholding, tools, tool holders, strategy, speeds, feeds, coolube, something like that

  12. Likes yugami, pmack, DieselMater86 liked this post
  13. #10
    Join Date
    Aug 2008
    Location
    Chicago, IL
    Posts
    166
    Post Thanks / Like
    Likes (Given)
    30
    Likes (Received)
    34

    Default

    What are you measuring after making parts and why? What value is this creating to ensuring that the parts being produced are good.

    Who owns the outcome of the production process? The QC guy or the machinist? If they're real machinists, can't they measure? If the parts are bad are these guys hanging out until someone tells them what to do?

    Proving out process capability will allow you to sample instead of inspect 100%.

  14. Likes 4 FN 27, Gordon B. Clarke liked this post
  15. #11
    Join Date
    Aug 2010
    Location
    Medina OH
    Posts
    1,714
    Post Thanks / Like
    Likes (Given)
    103
    Likes (Received)
    714

    Default

    Everywhere I have worked, I was required to QC every part I was capable of measuring.

    While some of the very complex parts I was not able to measure (such as what was run on 5 axis) I was usually given datum by the programmer, designer, or someone, to then be able to verify that in THEORY the part was good. Final verification by QC dependant of course.

    Batch runs, I would check all the details that I could, typically if 1+ aspects were good... USUALLY that meant the others were good too.

    Typically if it was a complex form, I was hard milling or hard turning, so could measure certain aspects, if HIGH precision, the forms, contours, cutting edges got jig ground after I was done with it.

    So, like the questions above, are these people machinists or operators? Even in the production environments I have been in, the operators are required to make continued checks. QC should be doing verification checks, not complete inspections.

    We have a 1:1 inspection ratio here....

  16. #12
    Join Date
    May 2009
    Country
    UNITED STATES
    State/Province
    Wyoming
    Posts
    3,206
    Post Thanks / Like
    Likes (Given)
    7723
    Likes (Received)
    5149

    Default

    Quote Originally Posted by SND
    Ideally the parts should be good before they get to them...
    Quote Originally Posted by mechanola
    The ideal would be that the makers make good parts in the first place.
    Quote Originally Posted by yugami
    If they're real machinists, can't they measure?
    ^^^
    I've always thought that QC inspection after the fact is a hell of a risk. Working drawings should contain enough data to allow in-process inspection and the machinists should be able to do that. It's the reason for calibrating their tools.

  17. Likes 4 FN 27, DieselMater86, tdmidget liked this post
  18. #13
    Join Date
    Oct 2007
    Country
    SPAIN
    Posts
    3,149
    Post Thanks / Like
    Likes (Given)
    1659
    Likes (Received)
    1104

    Default

    I've worked for a couple of USA owned UK divisions, and on the whole the UK is stripped right down.
    In going to the US companies USA sites, they tend to have QA personnel level at 10% of the headcount.
    This is Aerospace OEM type products - black box instrumentation etc.
    I believe Sikorsky also run the 10% rule too.
    But that's not just inspectors, it's QA engineers too.

    To the OP, 2x inspectors for that many machines is not enough.
    I'd be thinking 4x Inspection and a hands on QA manager.
    And a couple of the Inspection should be roving - picking up mid batch parts to look at...
    You have to have holiday and sick cover...

  19. #14
    Join Date
    Mar 2017
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    124
    Post Thanks / Like
    Likes (Given)
    58
    Likes (Received)
    114

    Default

    We are a fab shop. Our Set-Up Personnel are responsible for 1st part sign off. Then the Operator is instructed on the measurements to be checked and the frequencies. Final Inspection is an audit only. Basically making sure all the router oops are signed off and nothing is missing.

    We have 73 fabricators on the floor...when a customer asks "How many Inspectors do you have?" My answer is 73 and 2 auditors in Final Inspection.

    Quality is built into the parts via Machine Capability, Process Refinement, training and setting expectations. Hard to inspect quality into the parts once they are complete.

  20. Likes yugami, tdmidget liked this post
  21. #15
    Join Date
    Feb 2014
    Location
    UT
    Posts
    553
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    102

    Default

    OP, I think you have asked the wrong question. The right ones would be about how many machines and how many parts along with the complexity. Basic 2 op, 2D parts are much easier than complex 5 axis parts with tight controls. The drawings are also telling. a +/- .005" hole will be inspected different than a /- .0005" hole.

    It sounds like your quality guys are doing their job and not rushing to pass parts. If it holds up the train, get help. While we push operators to inspect at machines and give the tools to do so, there is NO WAY we will pass any part until it goes through inspection by a competent person with proper metrology background. You don't check a hole diameter with a caliper, yet I see it all the time.

    I would personally be looking at new measuring equipment to accelerate the work.


    We also have an inspector on the floor that moves around and double checks operators and looks for concerns. If a hole is hugging bottom of tolerance, some questions may get raised how old a drill is or if changes need made. I know one plastic part we do where the drill size was increased to what should be max size but the plastic shrinks back down after drilling so they come out perfect in QA.

  22. Likes mhajicek liked this post
  23. #16
    Join Date
    May 2010
    Country
    DENMARK
    Posts
    3,154
    Post Thanks / Like
    Likes (Given)
    4007
    Likes (Received)
    12665

    Default

    The best reason for having any QC is to avoid stupid mistakes being repeated. Corrective action is very important. What went wrong and why?

    If QC is to babysit machinists then you have the wrong machinists.

  24. Likes barbter, DieselMater86 liked this post
  25. #17
    Join Date
    Feb 2014
    Location
    UT
    Posts
    553
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    102

    Default

    Quote Originally Posted by Gordon B. Clarke View Post

    If QC is to babysit machinists then you have the wrong machinists.
    Thanks dad. I think we got it covered.

  26. #18
    Join Date
    May 2010
    Country
    DENMARK
    Posts
    3,154
    Post Thanks / Like
    Likes (Given)
    4007
    Likes (Received)
    12665

    Default

    Quote Originally Posted by huleo View Post
    Thanks dad. I think we got it covered.
    Doesn't sound like it to me kiddo.

  27. #19
    Join Date
    Feb 2014
    Location
    UT
    Posts
    553
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    102

    Default

    When you write a book, please let me know so we can all be like you.

  28. #20
    Join Date
    Jan 2007
    Location
    Flushing/Flint, Michigan
    Posts
    7,581
    Post Thanks / Like
    Likes (Given)
    377
    Likes (Received)
    6331

    Default

    Quote Originally Posted by huleo View Post
    ...... If a hole is hugging bottom of tolerance, some questions may get raised how old a drill is or if changes need made...... .
    Ouch..
    Why is the machinist or even button pusher operator not trained enough in QC to complain loudly about such.
    Why would you need a "special" person?
    If your measuring goes into a computer why does it not raise a big red flag?
    You simply should not have this as a concern. Ask yourself and your system why.

    I disagree with Gordon on many things.
    A book or long desertion on the net of his views and experience would be much welcomed.

    Why do people not "ground" their machine staff in 6-sigma, measuring, temp comp and variations?
    Most of these guys/gals on the floor and doing the work really, really want to make "perfect" parts all day long. Walk a mile in their shoes.

    QC is a verification, a second look.
    When it bounces why?
    The floor screwed up is not why.
    Perhaps you fire the guy who ran it. That all feels good but not sure it plugs the real hole.
    Bob

  29. Likes tdmidget liked this post

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •