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Centers, quickly

Gene_Davis | Posted in General Discussion on January 15, 2007 03:37am

I remember posting this before, quite a while ago, but here it is again. 

It’s a little mental shortcut to finding half of a fractional number, as in laying out for the centerline in a room 167-7/8″ wide.

Two methods are employed, depending on whether the whole number before the fraction is odd or even.

If it’s even, take half the whole number, and the fraction becomes the same numerator over twice the denominator.  If your room was 166-7/8, your center point is half of 166, or 83, plus 7 over 2 times 8, or 16.  Answer: 83-7/16.

Most everyone can quickly get to the ones with even whole numbers before the fraction.

But when it’s odd, the method becomes, take the rounded down half, or if it’s easier for you to think this way, subtract 1 and then halve it, then look at the fraction, add the numerator to the denominator, that becomes your numerator, then double the denominator.  For the 167-7/8 room, go half of the rounded down biggie, get 83, then add 7 to 8, get 15, and double the 8, get 16.  Answer 83-15/16.

If you mentally practice it enough, it won’t go away, and it’ll come in handy.

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Replies

  1. john7g | Jan 15, 2007 04:15am | #1

    167-7/8"

    what if you just worked your way from left to right

    1/2 of 16 = 8

    1/2 of 7 = 3 1/2

    83 1/2

    1/2 of 7/8 = 7/16

    answer is 83 1/2 plus 7/16 real easy to watch on the tape measure as you move towards target.

    1. brownbagg | Jan 15, 2007 04:26am | #3

      quicker, hook a tape measure to each side. wher they read the same number is the center, no math

      1. andybuildz | Jan 15, 2007 08:09am | #4

        LOL...my kinda mathWhere's Joe Carola when we need him? http://WWW.CLIFFORDRENOVATIONS.COM                                   

         

      2. Piffin | Jan 15, 2007 03:11pm | #7

        Yup, or use a canter marking tape measure 

         

        Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!

        1. User avater
          Sphere | Jan 15, 2007 03:56pm | #8

          Our last helper had one of those damm tapes.  It took him 5 times as long to call out a measure ment than a standard tape, due to all the extra crap on the blade.

          And I'd be standing ready to cut a pan, waiting on what I KNOW is a less than 25" cut, and he'd squint and sneeer and cuss, and call out "44" ....I'd say no, it HAS to be less than 25, I know that for sure, try again...

          "Oh, yeah...22"  I was reading it wrong....

          Those are a PITA for the less than bright bulbs on the tree.

          Spheramid Enterprises Architectural Woodworks

          The secret to a long life is knowing when its time to go.  M. Shocked

          1. FHB Editor
            JFink | Jan 15, 2007 05:15pm | #9

            haha, I have to laugh at this cause every time I use a center finding tape (or straight edge), I have to stop and scratch my head for at least 10 seconds while I try to remember how to read the dang thing! 

            ...still, besides being hindered by my thick head, it's a handy tool. Justin Fink - FHB Editorial

            Your Friendly Neighborhood Moderator

          2. User avater
            Sphere | Jan 15, 2007 05:30pm | #10

            Yeah, I shouldn't talk. I use an Ad Artists 2' rule in my shop, it has Center scale at 16ths, 1/3 OFF,10ths and 12ths ft/inches. If I flip it wrong. I can spend a LOT of time figguring out what the heck I am staring at...LOL

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          3. FHB Editor
            JFink | Jan 15, 2007 05:36pm | #11

            Tell me about it...I use an architects scale when drafting up plans (when I'm not using the computer), and if I don't mark the side of the scale that I'm using, I have to slow down and figure it out every time I pick the scale up again.Justin Fink - FHB Editorial

            Your Friendly Neighborhood Moderator

          4. User avater
            Sphere | Jan 15, 2007 05:41pm | #12

            Hey, slight hijack while I got yer eyes.

            I still don't get my message notifications to me, by email, but my subscribed thread I set, allowed 1 message to me that someone posted to it...something is screwy, any help? I emailed, and the reply was that "I'll ask prospero"...still no good and its been a month or more.

            I didn' change anything on this end.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          5. FHB Editor
            JFink | Jan 15, 2007 05:44pm | #13

            let me do a little digging. I'm no computer expert, but I know a few people who are...Justin Fink - FHB Editorial

            Your Friendly Neighborhood Moderator

          6. User avater
            Sphere | Jan 15, 2007 05:45pm | #14

            T.I.A.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          7. User avater
            SYSOP | Jan 15, 2007 06:35pm | #15

            Hello Sphere,
            Here is a sequence that I have had other users go through that has worked to restore message notifications:
            1. Delete your Prospero cookies.
            2. Then go into your Forum preferences (the my forums link) and uncheck the message notification box. Let that be for at least an hour as it takes 20 -30 minutes for all of the Prospero servers to catch up.
            3. Delete your Prospero cookies again.
            4. Log out of the forums
            5. Close your browser down completely
            6. Log back in and go to preferences and recheck the message notification box.Let me know how it goes.Mark
            [email protected]

          8. User avater
            Sphere | Jan 15, 2007 06:45pm | #16

            Will do!  Thank you!

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          9. User avater
            Sphere | Jan 15, 2007 07:51pm | #17

            Testing,1.2.3.

            I did it all Mark, I hope it fixed it self, thank you again for your help. Duane.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          10. User avater
            SYSOP | Jan 15, 2007 08:28pm | #18

            Test Response... Let me know if you don't get an email notification of this message.Mark
            [email protected]

          11. User avater
            Sphere | Jan 15, 2007 08:51pm | #19

            Nope. I hadda go to show unread to me to get it to appear.

            I am flummoxed, it was fine for yrs, then just last month or so it funky.

            Wait, I may ahve forgot to reset the check box...duh. I am sorry.

            Hang on..reply in a few minutes if OK with you?

             

            EDIT: yup, as I thought, I did neglect to re-check the box...thanks for your time. We'll see how it flys now.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

            Edited 1/15/2007 12:53 pm ET by Sphere

          12. User avater
            SYSOP | Jan 15, 2007 08:55pm | #20

            Also don't forget that the Prospero servers sometimes take a little while although all of my notifications have come through very quickly today.Mark
            [email protected]

          13. User avater
            Sphere | Jan 15, 2007 09:00pm | #21

            10-4. sometimes in the past the notifications were very tardy...but I have not had ANY, that was my concern. AOL on Dial up at 24.6 can be challangeing as well. Thanks .

            I owe ya one if we fix it.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          14. User avater
            SYSOP | Jan 15, 2007 09:06pm | #22

            Man that has got to be the scariest internet connection going... :) and Here I was complaining about how we only had 2 dedicated T1 lines coming into our building. I will never complain again.The other aspect of this is that I suspect if this does NOT resolve the issue then it is with AOL. Can you double triple confirm that somehow AOL is not blocking them? Make sure that Prospero is listed as a friendly site or whatever AOL terminology is used.Mark
            [email protected]

            Edited 1/15/2007 1:09 pm ET by SYSOP

          15. User avater
            Sphere | Jan 15, 2007 09:57pm | #24

            I DID do a CCleaner as posted by CapnMac a few weeks ago, and I am sure I "allowed" from Taunton.com..does Prospero use a different something?  I saved my registry ( listen, I am not a geek) and maybe I have blocked it by mistake?

            Seems like the timing was real close...but I did recieve a notification that my SUBSCRIBED thread had a response, so my email addy is viable, butthat thread had MANY posts, and I got one email notification.

            Should we move this discussion to a new place or continue in an email fashion, so as to not defray the OP's intent?

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          16. User avater
            BossHog | Jan 15, 2007 09:31pm | #23

            "if I don't mark the side of the scale that I'm using, I have to slow down and figure it out every time I pick the scale up again."

            I've had that problem too. At times I've blocked off part of the numbers with correction tape so I don't accidentally use the wrong scale.
            Shared joy is a double joy; shared sorrow is half sorrow. [Swedish proverb]

          17. User avater
            Sphere | Jan 15, 2007 10:14pm | #25

            About SCALE...I worked for cheepskate..he broke his 250' tape end off.  Decided it was cheeper to re-attach the end at the 12" and figguer it in...well, he forgot one time.

            Laid and poured a footing for an elementary school ( I just LOVE the Irony in that) and it was all off by a foot...track hoes yanking footers was as far as it went, but it cost him a bundle.

            I gave him 5 100' tapes for xmas that year. LOL And one 250' fiberglass surveryors type...I quit before it got done, and heard that he did something else even more boneheaded, and went belly up.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

          18. blue_eyed_devil | Jan 15, 2007 10:29pm | #26

            Great story Sphere.

            My engineer brother did the same thing with a tape, chopping one inch off it, then fixing it. He was out of town when his  12" x 15" basement window got broke. His best buddy came over to fix it, then wondered why the pane he bought from the hardware was one inch short, both ways LOL!

            blue"...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."

            From the best of TauntonU.

          19. User avater
            Sphere | Jan 15, 2007 11:00pm | #27

            This was the same feller who got p.o ed at his general Cont. and went out and moved his GC's batter board nails an inch outta line.

            What goes around, wil come around, and getcha.

            Spheramid Enterprises Architectural Woodworks

            The secret to a long life is knowing when its time to go.  M. Shocked

  2. User avater
    McDesign | Jan 15, 2007 04:26am | #2

    Yeah, but really, you're kneeling in the center of the room, so measure some arbitrary distance from both walls to where you are, about the center, mark those, then split that difference.  Plus, you're right there in the center to make your marks.

    Your way you have to walk from the smart end of the tape back to the middle of the span to make your mark.

    Along the top of walls, it's even better - most rooms are under 16' wide, so your regular 25' Stanley will stick out half of that, as you stand on a chair in the middle of the wall measuring left, and then right, split, and make your center mark - never have to move.

    Big rooms get the FatMax and its manly 11' stick-out.

    Forrest - happy with my method

     

    1. Jer | Jan 15, 2007 02:49pm | #5

      Exactly the way I've been doing it for years.
      KISS = Keep It Simple Stupid

  3. blue_eyed_devil | Jan 15, 2007 03:05pm | #6

    Gene, thanks for that mental math tip. I've used all of the methods that the boys have just suggested and I can think of another too, but I like yours because it uses math in it's procedure.

    I often use sticks  to narrow my centering dimensions down. These sticks can vary from size from 1x1's to 2x4's. They can be any length. I bump the stick to both edges and mark the end on the plate, then use my tape to find center...unless the marks are close enough, then I do it by eye.

    Sticks can be wonderful helpers....much faster and they don't hook on the wrong side LOL!

    blue

    "...if you just do what you think is best testing those limits... it's pretty easy to find exactly where the line is...."

    From the best of TauntonU.

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