the different weight codes.........I do not have scales sensitive enough
to tell
the difference but perhaps the post office, UPS, etc scales would do
it.......
As time permits I will put that on my
short list !!...........
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Original message from "George Lendich" <lendich@optusnet.com.au>:
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Kelly,
Yep! your right, I was referring to the
matching code. I mentioned this in case anyone would take rotors from
different sources, however if they came from the same engine their likely to
be matched.
I don't know how the counter weight is matched,
I have seen and heard of rebuilds that do all sorts of things and even
balancing which is not as good as factory balancing. I believe it's to do
with what's ( what weights)allowed for in the physically
balancing.
For those uneducated in the physical balancing
process, the e-shaft is spun up with dummy weights (bolted onto the
e-shaft lobes) that represent the weight of the rotor, all seal weights
( except apex seal and spring) and the oil in the rotor. The counter weights
are then adjusted for best balance. Adjusting involves adding or removing
metal from the counter weights. I don't believe static balancing is accurate
enough fro a 2 rotor ( because of the rocking couple) but might be good
enough for the single rotor. I believe that's what Richard Sohn has done to
date for his single development.
I think if we take parts from other engines (
as I am doing ) it would be advantageous to know the variance of the code
system. I believe someone was working to identify what the difference in
code represented in weight - but no final outcome to my knowledge. If we
could also nail down the weight of the corresponding counter weight it would
solve a lot of problems for experimental builders. Instead of matching
things we could just weigh them.
Is there any information you can give on
different weights from your 3 sets?
George ( down under)
George,
I presume you are making reference to the letter
(A,B,C,D) weight code for
rotors........Engines that have not been opened (stock) will have
matched weight
rotors within one letter of each other (that is
AA-AB-BB-BC-CC-CD-DD)......
I have not heard of such a weight code for the counterweights
but I stand to
be educated if there is one.......I have managed to collect 3
sets of 89-91 rotors
(9.7 to 1) with matching weight codes.........FWIW
--
Kelly Troyer
"Dyke Delta"_13B
ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold
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Original message from "George Lendich" <lendich@optusnet.com.au>:
--------------
Kelly and All,
Even when the weight of the rotors and the
counter weight are confirmed as being compatible - one should also
remember the lettering stamping system which matches a paired set,
for balancing through similar weight. I have never been able to confirm
what the difference in weight is exactly, which is a shame.
George ( down under)