OK folks I need your feedback on this. Are you learning anything from this?
Is it clear what is going on?
Paul Lamar
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Okay Paul,.........For the sake of those subscribers who are having a hard time
understanding the theoretical technicals :) and are more interested in the
practical aspects/techniques, I'm going to take a shot at VERY VAGUELY
explaining it the way I've seen it from the beginning.
For the benefit of simplicity we'll use The RWS Re-Drive since this is where
the ACRE front MM plate combo originated from.......The re-drive is mounted to
the engine via a spaced out (forward) 1/2" al transition plate, which is bolted
to the 13B's outer perimeter........The mounting diameter of the re-drive
(footprint) is quite smaller than the plate's mounting diameter bolt
circle........Now visualize a 12" dia musicians DRUM, which has a rigid
exterior, with a membrane on top.........Now if you glue a can 6" dia x 12"
high in the middle of the membrane, and then pull on the top of the can
with "x" lbs. and let go, you'll notice the can will oscillate back and
forth......Un-glue that can and re-glue a 10" dia can same height & weight as
the the other and pull on the top with the same "x" lbs. and let go, you'll
note that the oscillations are less and smaller......This would be considered a
STIFFER installation........Anything you do outside of the skins attachment
point, will have no effect on these oscillations. What I mean by this is, if
the membrane that overhangs from the drum's exterior can be cut, burned or
stapled to a wall, it won't make one bit of difference to the end results......
Now what is happening here is that by increasing the FOOTPRINT you are in
essence DECREASING the UNSUPPORTED material between the dia of the can & the
outer membrane support......Making the plate thicker will increase the
stiffness but ideally what you really want to do is increase the footprint to
match the drum's outer dia. this would in MOST cases be considered ultimate
stiffness.......Obviously orientation, external jerking, shaking, dropping etc.
will most definitely aggravate all of the above situations and cause failure,
UNLESS you take all of this into consideration BEFOREHAND..........
With all
that said, in my opinion there's absolutely nothing wrong with the ACRE's mm as
it's only a stretched version of the original re-drive which has been cleverly
modified by Paul to double up as a very efficient, light and filthy CHEAP front
mm ;)...... Jerry you're going to make a lot of people fly faster, safer &
cheaper, thank you......Dan, you have instilled a sense of safety, confidence &
security among'st us all, thank you......Bulent, tsk,tsk, not nice :) nobody's
screwed, au contraire' mon ami, they are re assured now that this is the most
analized MM ever ;)
For me personally I planned on mounting directly to the outer bolt circle with
a front housing a la Bulent's, Ian's even if it meant CNCing to death :) That
was until Paul introduced the "Ultimate PSRU/MM", now we're talking caviar,
"It's the PRIMO way to go".......So, I'm thinking, thinking, thinking...ooommh!
Butch
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