Jerry-


                 The only thing keeping my engine where it belongs  is a
             2x4.  This

                 worries me, since I share the hangar & my airplane  gets
             moved around

                 when I'm not there.  So, to answer your question,  getting
             the rear mount

                 was my #1 project.  I do have the local guy who could
    fab it
             for me --

                 he's ready to whip it out for me quickly once  given the
    right

                 measurements but he doesn't weld, so I'll have to  find a
             welder too.


             Mark here is a photo of the prototype strut bracket.  Two
    things to
             note:  one, the inside measurement is 1" which is also  the
    outside
             measurement of the rod end.  You may have to file the  inside
             faces of
             the bracket to get a smooth fit.  Secondly, the  bracket is
    off set
             toward the pilots side about an inch to clear the pan  bolts so
             that  you
             can get a wrench on them.  check to make sure it will  still
    line
             up with
             the firewall bracket.  If it will do the job, I will
    complete the
             welding and send it to you.  You will have to enlarge the
    bolt holes
             (Rod End) in the bracket.  Also, the bolt holes that  attach to
             the pan
             will have to be enlarged (presently drilled for 1/4  inch.)   I
             am not
             set  up  yet to make the final version but it will be
    similar to
             what
             you see here. Lastly, there is a lip on the pan that  will have
             to ground
             away in the area of the bracket.  I do have an extra  Barry
             washer.   Jerry

             P.S.  It is heavily constructed.  If you want to drill  a few
             lightening
             holes, go for it.


         Jerry -

         Thanks - I'll drive out to the hangar tonight after work &  check
         clearances & whatnot and get back to you.

         Mark


    Well, the hard point itself doesn't allow for any offsetting at  all.
    The bolt hole is dead-center & there is no structure anywhere else
    (e.g., toward port) to tie into.  The rod ends don't look like  they
    would support any kind of angle to the strut.  Further, the  prototype is
    set up for bearing from underneath.. Based on the photo, it  looks like
    the mounting brackets don t extend out enough to allow a strut  to come
    down from the top.

    So - it looks like this bracket won't do the job for my  installation.
    Thanks, tho.

    Mark

    What is the matter with coming up from the bottom Mark
    as in this 3D?

    Coming down from the top is not out of the question.
    That big 1/2 inch shank on the rod end can take some bending  loads.
    There are ways around it. Do me a favor and use a fish
    scale hooked to the back of the engine to measure the force
    required to level the engine when you have a prop on there.
    Or if you don't have a prop yet you can hang the weight of
    a prop off the prop flange. This  will tell me precisely
    where the CG of your engine is so I can  calculate the exact
    loads on the rear motor mount.

    Also are you thinking of replacing the oil pan? If so
    a bracket suitable for coming down from the top can
    be incorporated in the back panel of the oil pan.



Paul-

The design of the M2 has the fuselage forward top skin taking  torsional
loading from the engine.  The 5th hard point is part of this & the
designer prefers that it be used when mounting a high power engine.
He's ok not using it up to about 220HP at the prop.  So I was pretty
happy to dedicate it to the rear engine mount.  And, of course, Jerry
has already built a perfectly lovely engine mount, so the idea of
mucking about with it to add additional tubes for the rear mount don't
satisfy.  Finally, I was liking the strut with rod ends design because
it would make it trivial to adjust thrust angle should it be  necessary.

You are right that much of the weight is already carried by the SBeam.
We picked the engine up by hand & were suprised how far forward the
redrive brought the CG, even without a prop.  I don't think a prop  will
result in a CG at the SBeam, but it won't be all that far off..  I  will
get a scale & measure the weight at the rear.  I'll add weight to the
prop flange if anyone can tell me what a 3-bladed prop weighs.

I was not planning to replace the pan.  I agree it's shape is a
nuisance, and that it will be difficult to drain oil from once the
radiator is mounted.  But I wasn't seeing a compelling need to  replace it.

Mark

I just sent and oil pan alternative. Move the ears over to the center
of the pan and space them far enough apart to clear the center pan  bolt.
The 1/2 bolt going through the pan ears and the rod end will
take considerable bending load no problem. You will
then need short spacers between the rod end and the pan ears on
each side. The same trick will work on a Jerry Hey style
steel bracket.

Paul Lamar

Here is what I had in mind.

Paul Lamar

Paul and Mark,  can we not build a strut bracket similar to the
prototype but with the strut centered?  We could use a piece of
square tubing with one side milled out to form a pocket so that the
bolt head could be reached with a socket.    Jerry


OK here is the proplem. Mark wants the rod end in the center.
This is looking at the front of the engine without the front
cover on. As you can see the left pan bolt hole is too
close to the center. So put the rod end in the center, move the tab
over  and use a spacer on the 1/2 bolt. No biggy. Also you can get allen
metric screws from McMaster Carr to give you more clearance
around the pan bolts heads.


Paul Lamar


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