Announcement

Collapse
No announcement yet.

Producing an Oval on a Mill

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • oldtiffie
    replied
    Not all on a mill ..... but ..............

    Originally posted by Pherdie
    Is there a way for an HSM to produce an oval plate using a single setup??

    I realize that three different realignments (foci/centers) can be used in totality to produce an oval (assuming you can get the multiple circumferences to properly transition at simultaneous tangental points!!), but I'm wondering if I'm overlooking an easier more precise approach, using just one set up. I'd like to produce a 2" x 1" oval, 1/2" in thickness (mild steel).

    Fred
    Fred.

    As good a method as any is to use the ("old-fashioned") manual drawing board method (4 tangential arcs) which requires a straight edge, a pair of dividers, a centre punch and hammer and some "Dykem" (blue mark-out fluid) or similar.

    http://www.google.com.au/#hl=en&sour...f33b0d2303fec5

    Mark it out, centre-punch it and cut it out roughly with a band-saw. Then use a a pedestal or angle grinder to get closer to the mark-out. Then use the belt sander and disk sander if you have one to finish-off or use your pedestal grinder and a file and emery ("wet and dry") paper.

    I know it isn't a solution for doing it on a mill but to finish it on mill is very difficult without CNC.

    There is no reason why your mill can't be used as part of the "roughing" or "pre-finishing" stages but the sanders, grinders, file and "paper" will still be needed.

    Leave a comment:


  • Guest's Avatar
    Guest replied
    You have a boring head?
    Tilt the spindle about 30°, insert an appropriate tool for outside work (not boring here) into the head and feed at the Z-axis (NOT the quill).

    Done.


    Nick

    Leave a comment:


  • Astronowanabe
    replied
    make a "smoke grinder" or "bullsh!t grinder"

    OR

    cut a slice out of a 1" rod at a 26.5651 degree angle and mill or grind
    anything that is not perpendicular to a face
    Last edited by Astronowanabe; 03-12-2010, 03:02 AM.

    Leave a comment:


  • Ian B
    replied
    Pherdie,

    What's it for, how big, how thick? That might affect the suggestions on how to make it.

    eg. if it's shim stock you're making it from, sandwich it between hardwood discs, bolt the sandwich to a rotary table. Mount the r/t at an angle on the mill's table, fit a long series endmill and just mill away - you'll get an oval (ellipse?). It'll be an oblique slice through a cylinder. The more the angle, the less round the oval will be.

    Ian

    Leave a comment:


  • easymike29
    replied
    A cross slide on a rotary table will do it.

    Gene

    Leave a comment:


  • Black_Moons
    replied
    Originally posted by KiddZimaHater
    Just brainstorming, but an arm attached to the mill near the spindle could be used as a crude tracer, (kinda like a Pantograph), to trace a stencil mounted on the table next to your part?
    ??? Maybe ???
    Thats a pertty cool idea actualy. Especialy if you did something like mount a TDI on the end of the arm. just align TDI to X axis, continualy feed Y axis and adjust TDI to constantly read 0. swap X/Y axis once you pass 45 degrees around the template

    Of course, then you need an oval template to start off with.. but whatever.

    If accuracy is not as criticial, just a printed sheet and a needle could likey produce an oval accurate enough to just require some light sanding to make it 'appear' perfict.

    Leave a comment:


  • lazlo
    replied
    There's a great article in HSM magazine within the last 3 years about making a ellipse jig. It was called "Something is out of round," or some such. At a 10,000 foot level, it was the jig that Black Moons posted with acme screws to set the major and minor axes. I'll see if I can find it...

    Leave a comment:


  • KiddZimaHater
    replied
    Just brainstorming, but an arm attached to the mill near the spindle could be used as a crude tracer, (kinda like a Pantograph), to trace a stencil mounted on the table next to your part?
    ??? Maybe ???

    Leave a comment:


  • Evan
    replied
    The term "oval" has no rigourous meaning. Therefore there is no formula or specific method to make one. It simply means a shape somewhat like the outline of an egg since the word is derived from "ovum" which is Latin for egg.

    If what you want is an elipse then it is a different matter. The coordinates for an elipse may be calculated to what ever degree of precision you require.

    Leave a comment:


  • JoeCB
    replied
    Well if you only have to make one and you are not doing this for a living.. I would start out in the lathe, make a 1/2 in thick mushroom head 2 " dia on a 1" dia stalk. Set this up in the mill and get out your computer,,, calculate and tabulate all the X - Y offsets based on say .005 steps in the X direction.. and have at it for an evening or two.

    Joe B

    Leave a comment:


  • Black_Moons
    replied
    Sure, just build one of these:
    http://woodzone.com/Merchant2/graphi...1/oval-jig.jpg
    the two 'tabs' slide in the two slots and create an oval motion depending on the distance beween the two (where they are connected to the main 'beam')

    Leave a comment:


  • Pherdie
    started a topic Producing an Oval on a Mill

    Producing an Oval on a Mill

    Is there a way for an HSM to produce an oval plate using a single setup??

    I realize that three different realignments (foci/centers) can be used in totality to produce an oval (assuming you can get the multiple circumferences to properly transition at simultaneous tangental points!!), but I'm wondering if I'm overlooking an easier more precise approach, using just one set up. I'd like to produce a 2" x 1" oval, 1/2" in thickness (mild steel).

    Fred
Working...
X