Countersunk Allen Angle

Discussion in 'PSI Superchargers Tech Questions' started by altered boy, Mar 27, 2014.

  1. altered boy

    altered boy Outlaw Altered

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    needing to countersink some allens in a manifold project... anybody know the countersink angle of a 7/16-14 allen?

    combed the interwebs... but no definitive/common answer

    and what i'm using is the standard grade 8 type fastener from a local metal shop nothing exotic or off the wall... although my project sorta is lol


    [​IMG]
     
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  2. WIZBANG

    WIZBANG Member

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    82 degree I would think.
     
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  3. Bob Meyer

    Bob Meyer Comp Eliminator

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    82 is most common
    90 is out there more than you think
    100 (aircraft) is obvious.

    Hold a known (marked) good countersink against the threads, hold up to light to see if the angles match. The 8* difference can be seen easy.



    Bob Meyer
    Meyer Race Cars / San Diego
    2014 Our 49th Anniversary
     
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  4. altered boy

    altered boy Outlaw Altered

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    yep! that's what I ended up doing. had no idea what degree my bit might be. looks to be the common 82deg deal. much appreciated!
     
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  5. blue boat

    blue boat New Member

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    82* is sae standard american & 90* is for metric screws
     
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  6. Soldierboy0098

    Soldierboy0098 Active Member

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    Fastenal sells a countersink bit for that, it was less than $50 if I remember right, Just call the local branch and tell them the size of the bolt (The tool gives you a range of sizes) They refer to that style of bolt as a flat head socket cap screw and I would tell them that to avoid confusion. Alternatively if you could find the tool on there website it will probably tell you the angle.

    Hope that helps,
    Trevor Sherwood

     
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