George Lendich wrote:
Butch,
See comments below, marked ##.
Very interesting indeed, somewhat different to my own concept, but
certainly
the basics are similar to my latest solution especially in regard to
the
side MM's, although I've got my starter at 3 o'clock and have my MM
smaller
i.e. 150mm (see attached photo)
******George, the difference in MM pad height is .591" (15mm), which in
our
case proves to be beneficial since it will allow the MM bkt mounting
bolts to
be further away from the MM's resilent cluster and allow it to be tucked
in
tighter against the MM bkt resulting in a a shorter MM arm.
## I wish I could say things like this - I wish I knew what a 'resilient
cluster' was, sounds ominous!!
Why have you cut the bottom-off the flange -doesn't it add stiffening
and
stress transfer !!?
******Not really George, it's considered "Air Gapped" and it's just dead
weight...The stiffening is amply provided for by the Flange's corner
radius
and wall thickness, stress transfer remains intact and is still
dissipated by
the engine mounting face in essence there's no change in dynamics.
(Reffer to
side view)
##Thanks for that info, I can understand that one.
I've had a lot of trouble getting 2nd hand starters and have opted for
a
Turbo starter as all Aussie imports are Turbo the non-turbo are
impossible
to find.
I find the Turbo has a smaller foot-print and therefore takes up less
room,
can you include that as an option !!?
I can send the details to you if you wish !
******Absolutely George, please do!!!, especially since smaller is
better :) .....After-all this is a Yankee/Aussie Joint Venture, plus I
don't
see any problem what-so-ever fitting it in as I expect it to be smaller
in
distance between mounting holes than Tracy's 5.512" (140mm) ....IF at
all
possible please send it to me directly before you leave on Friday,
## It's on it's way!!
this way
I'll have a welcome home present when you return :)
Speaking of....I don't show a footprint for Tracy's Starter as I don't
have
access to one to extrapolate info from, could one of you guys that have
one
handy, post a dimensioned sketch so I can check for possible
problems...Need
only 2 volunteers (Just to double check) for this, and please
immediately
post your acceptance of this undertaking in ACRE so as not to jam Paul
with
excessive e-mails.
The stiffeners near the mounting bolts are very close- I found I had
to move
them a bit in the prototype to allow sufficient room.
Why are the two at the extreme bottom sides - is there a strength
issue
there, I thought 2 at the sides and one in the middle would be enough,
that
way we could move them away from the mounting bolts,
giving a little more room to move.
******You've got Good eyes George, I wouldn't have caught it, since the
standard Flange Head 10mm, 8 grade bolt fits nicely (See Bolt
Clearance-1)
FIXED already (See Bolt Clearance-2)
## Ah that's better!!
******A picture is worth a thousand words, 2 of them side by side,
UMTEENTH
more (See attachment "Comparison").....Esthetically the one on the right
looks Heavier and much more Robust doesn't it?....The Bellhousing on the
LEFT
is in what I call "The GREEN Phase" (Before structural analysis), the
one on
the RIGHT I call "The RIPE Phase" (Profiled), as it reflects the
strengthening of the weakest points of the previous....And amazingly,
all it
took was one add'l WELL PLACED Fin (Which was a trade-of to the piece I
removed from the bottom of the Flange), and obviously, the mirroring of
the
Tripod Pads....This resulted, in the one on the right being more Rigid
and
Stronger WITHOUT any INCREASE in weight.
BTW George, 6 of those Fins can be 2pc Triangle Braces (I'll post a
Detail
later on), however the 3 Tripod Pad Fins MUST be wrapped around as
shown,
this is NON NEGOTIABLE.
## I understand !! Paul suggested triangles some time ago as the Ross uses
triangles - they are a lot easier to cast (shorter taper). I guess the 3
tripods need the extra for the extra strength if used in aerobatic
application.
Something like this is a must for machining anyway. I could make the 3 ribs
as high as the PSRU mounting pad and just mill the lot of level, giving a
stable base (when turned over) for the internal milling and drilling.
I did consider having a starter location on the opposite side to allow
flexibility but couldn't get around the bolt hole being as you say
"smack in
the middle of the starter" I would like to see your design to get
around
that one. I gave myself a real headache trying to get around that
problem.
******I'll draw it up and post it first chance I get George, if for some
reason or other it's not there when you get back, please remind me.
## OK will do, I've got a couple of ideas myself.
I have been considering a deeper housing with more curve for
additional
strength, or a ring shape extension like the Ross, but these designs
would
have difficulty allowing Tracy's PSRU to be attached without
modifications.
I can see your trying to make sure Tracy's unit fit without any
modifications.
Sorry to rush a response on this as I would like more time to "mull
it
over", but I've got to go away for a week on Friday.
I would like to see other opinions on your suggestions (drawings)
however.
I don't think this is an optimum solution but may be the best for
something
universal.
I would like to hear something from Tracy on it unless he is 'dead
against
it'.
I'm not interested in trying for a universal design if some of the
main
players are against it, I'd rather just do my own thing .
Just give me some more time to consider any possible problems OK!!
******Well George I disagree with that thinking.....There are gobs of
practical reasons having to do with production quantities, up-front as
well
as on going costs, tooling, tooling set-ups, cost savings to the
purchaser
etc etc, to counteract your argument, but hey maybe I'll come up with an
excuse to fly the Limo Downthere and we can discuss them in person over
a
glass or 2 of Red ;)
Plus you forgot the fact that we are very needy of a decent well
engineered
affordable Transitioning Bellhousing for the 13B.
Butch
Butch,
I'm not trying to be negative, I do very much appreciate what your doing. I
just don't have the skills to do, what you can do - not many people have!!
There just doesn't seem to be much interest previously and I feel I'm just
banging my hear up against the wall - I was just about to give-up on trying
to meet the US needs until you come up with this alternative.
But you are right about the economies of scale, that will keep prices down
for everyone- man those CNC machining costs are savage. Just so everyone
knows it cost me $650.00 just to have the prototype machined-up.
Paul would be aware of this that's why he's bought his own machine - however
my own skills level isn't sufficient to do this type of accuracy, even with
Jigs.
I'm still looking at every alternative and talking to people in the
industry.
Sorry to be so long winded!!
BTW and as I said to Paul, your always welcome here Mate!! I will put you up
and feed ya, no problems!!
George
A lot of that one off machining cost now adays is due to the time/labor of generating
the NC mill program. If you can beg borrow or steal a copy of Master Cam
and learn how to use it to generate NC mill programs I can machine parts
at much lower cost. As a practical matter it would also be desirable
to obtain and learn Rhino for the initial design.
Paul Lamar
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