Page 1 of 2 12 LastLast
Results 1 to 10 of 14

Thread: Alignment Issue

  1. #1
    Join Date
    Jun 2006
    Location
    NE NC/SE Wisc.
    Posts
    1,276

    Default Alignment Issue

    I have a tube, 6" long and 1.5" in OD. I need to drill 3 holes, each 120 degs. from the previous one. These holes are through the wall of the tube. 0.25" from the end of the tube. There is no problem drilling the set of holes on the first end of the tube as is mounted in my vertical rotary table (RT) and then drilled in the correct locations.

    However, the problem occurs when I need to drill another set of 3 holes in the opposite end of the tube. These holes are to be in the same angular position as the first set of holes. How would I align the tube in the RT so that when the hole was drilled it would be in correct alignment with the matching hole on the other end of the tube? Once I get the first one lined-up, the rest will be easy. Getting the first one aligned is the problem. Appreciate any assistance or ideas. Thanks.
    Bill

    Being ROAD KILL on the Information Super Highway and Electronically Challenged really SUCKS!!

    Every problem can be solved through the proper application of explosives, duct tape, teflon, WD-40, or any combo of the aforementioned items.

  2. #2
    Join Date
    Oct 2002
    Posts
    1,739

    Default

    how close does it need to be? how about good old fashioned layout lines.
    run one down the side of the tube and use that as your location.

  3. #3
    Join Date
    Aug 2003
    Location
    North America
    Posts
    429

    Default

    Mount the tube in your lathe and scribe a line lengthwise down the tube using a cutting tool laid on its side just touching the work and moving the carriage from one end to the other. Using a small prick punh will then get you within a few thousandths alignment from one end to the other.
    Arbo & Thor (The Junkyard Dog)

  4. #4
    Join Date
    Aug 2006
    Location
    Taylorsville Ky
    Posts
    6,056

    Default

    I use Starrett key seat guides like these. http://toolmonger.com/2008/08/21/dea...eat-clamps-34/ You can use them on almost any scale to scribe a straight line on a shaft. I have not bought from that company, I just did a google to get a photo.
    It's only ink and paper

  5. #5
    Join Date
    Mar 2001
    Location
    East Iowa
    Posts
    376

    Default

    Lay the tube in the V of a piece of angle iron, line up the edge of the angle iron with one hole or it's mark, then use the edge to scribe a line along the tube.

  6. #6
    Join Date
    Nov 2009
    Location
    Winchendon MA
    Posts
    1,138

    Default

    After drilling the first holes clamp a VEE block on to the tube in the middle, indicate flat, turn pipe around and indicate flat again with out moving the VEE block, you can't get much closer than that.

  7. #7
    Join Date
    Sep 2011
    Location
    Langley, British Columbia
    Posts
    1,269

    Default

    Quote Originally Posted by duckman
    After drilling the first holes clamp a VEE block on to the tube in the middle, indicate flat, turn pipe around and indicate flat again with out moving the VEE block, you can't get much closer than that.
    This idea gets the prize. Simple and more accurate than anything else. We use the same principal when we're bending tubes and have to align multiple bends in a single piece...
    Keith
    __________________________
    Just one project too many--that's what finally got him...

  8. #8
    Join Date
    Mar 2010
    Location
    Winnipeg Manitoba
    Posts
    2,411

    Default

    Put a tight fitting pin or if threaded, a threaded pin, into each hole at one end, flip and use the pin as a "stop" against the side of a jaw (of course it is a bit more complicated mathematically, i.e. knowing the center of the pin, and would be fiddly the first time, still...)

  9. #9
    Join Date
    May 2011
    Posts
    870

    Default

    Put the tube in a mill vise and put one hole centered at each end at the proper spacing from the edge. Now set the thing up in the rotary table and locate the outboard hole with a drill blank or piece of straight stock of the same diameter in the drill chuck. Rotate and put in the other two holes ... then, take the part out, flip it, and repeat on the other side

  10. #10
    Join Date
    Aug 2002
    Location
    Albuquerque
    Posts
    3,155

    Default

    Quote Originally Posted by DATo
    Put the tube in a mill vise and put one hole centered at each end at the proper spacing from the edge. Now set the thing up in the rotary table and locate the outboard hole with a drill blank or piece of straight stock of the same diameter in the drill chuck. Rotate and put in the other two holes ... then, take the part out, flip it, and repeat on the other side
    +1 Or as they say "ditto" . :-)
    ...lew...

Posting Permissions

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