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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default Is 14V cordless sds drill ok for diy?

On 21/04/2021 15:22, Theo wrote:
Mike Halmarack wrote:
On Wed, 21 Apr 2021 05:44:53 -0700 (PDT), Murmansk
wrote:

I've got a Makita 18V SDS drill and it's very good - although I've only
used it for drilling 6.5mm holes in very hard brick and concrete, which
it does well.


Very clearly put. But not encouraging in terms of the viability of the
14v version.


What we're concerned about here is the power delivered. P=V^2/R and so the
power increases with the square of the voltage.


It would if a motor was a resistor. Since it isn't you are talking total
crap

However what isn't
discussed is decreases in the resistance which will also contribute. An
improved battery with a lower internal resistance can deliver more power,
even at the same voltage. This is why a lithium ion drill is better than a
NiMH of the same voltage - the NiMH has a higher resistance and so can't
deliver as much current.

More total crap

However it's hard to beat a square law, so I would be looking at trying to
get the higher voltage.


And a final piece of total crap just to get the bullseye
Theo



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Religion is regarded by the common people as true, by the wise as
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