How much faster Rotary Hammer vs. my Hammer Drill

Discussion in 'Tools' started by kurango, Jan 4, 2013.

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  1. Jan 4, 2013 #1

    kurango

    kurango

    kurango

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    I have a 7.5 amp motor hammer drill. This hammer drill takes me 40/45 minutes to drill a 3/8" hole 2.5" deep, drilling into beach rocks. It take me a few seconds to drill the same hole into concrete.

    How much (many minutes) faster would a 5.2 Amp SDS Plus Rotary Hammer, 2920 blows per minute do the same hole into the beach rocks?

    TIA,
    kurango
     
  2. Jan 4, 2013 #2

    Wuzzat?

    Wuzzat?

    Wuzzat?

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    7.5a x 120v = 900w.
    5.2a x 120v = 624w.
    The second one would take approx. 900/624 = 1.4x longer. My guess at the tolerance on this number is +/-50%.

    There is also something called "the force of a blow" which relates to pile driving but the formula might be somewhat applicable here.
     

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