Subject: S-Beam / RD1C install problems
From: Rotary Engine
Date: 8/16/2005, 3:57 PM
To: AA-me

>
> > Big Snip
> >
> > I think we have it figured out. Jerry assembled his and found
> > the problem.  Here is the solution. Find a tig welder
> > locally and send me the bill. My fault for not catching this.
> > Cheaper than shipping it back and fourth.
> >
> > Paul Lamar
>
> Paul, your drawing only shows the notches on one side but I sure  you
> want them on both sides.  The piece that is to be welded on just  sits
> on top of the S.beam I presume.  Is it the same for both  sides?   Can
> Rhino pop out a measured 2D drawing?    I will have to provide this
> modification for all future S-beams and of course,  for those  already
> shipped.      Thanks, Jerry
>
> They are there you just can't see them :)
> See the last message.
>
I'm going to try and get all this rework done this weekend.  A few
more questions on relocating the starter mount point.
- In the CAD drawing, you show the starter at a 5.3-degree offset  from
the horizontal.  This places the existing mounting flange holes
exactly wrong with respect to the bolt holes for the mount.  I  note in
Al's install, he seems to have shifted the starter a bit to allow one
flange hole to align correctly, and then redrilled a new hole to  align
with the other mounting bolt hole.  I assume this is what was  meant to
be shown in the CAD.
- Based on the CAD, it would seem that a chord drawn between the 2
existing bolt holes would allow one to easily locate the center of  the
new starter hole -- simply measure the flange hole to gear center
distance & mark it on the chord.  This would also be the correct
distance from the mounting seal center point.  Correct?  Easier than
trying to measure x degrees...
- I assume the 02.67 callout indicates a 2.67 diameter hole.  I note
tho that the R1.34 is more than half of 2.67 -- which is it?
-  Best way to cut the Tracy mounting plate for the new starter
position?  I'm thinking I need to find a machine shop to do it.  Also
- any reason not to cut the mounting plate so it aligns with the
bottom of the s-beam?  Saves a little weight & I don't see any reason
to keep the extra material.
- I will need to buy tube spacers for the starter area of the mount.
What material should these be?
Thx,
Mark
Yes you are right Mark. Here is another picture of Al's starter.
The radius number is a rounding error. I can reset Rhino to give  it to the
nearest .0001 of an inch if you wish :) Tracy called out 2.67".
That is close enough as it is not that critical. Glad you are so
observent.
Paint the plate in that area with blue Dykem. Scripe the out line
of the slot desired. Center punch and drill a bunch of small holes
just inside the scribe line using a drill press. Use one of those
new fangled round hack saw blades to cut between the holes. Rat
tail file to final size. Takes longer to talk about it than doing it.
As I said the slot is not critical. The two ten MM bolts are
more than strong enough to hold the starter in place.
Steel tubes will work fine. Place close fitting AN type washers
under the ends of the tubes to keep them from digging into
the aluminum.  Hard to find thick wall aluminum tubes
can also be used or drilled out of round bar stock in a lathe.



Paul-

The CAD drawing of the cutouts needed on the SBeam are not correct.
The bolts/nuts do not plunge below the top of the beam far enough to
require 2 separate cutouts on each side.  Instead, a single cutout of
4" is required on each side.

The left edge of the cutout begins 1.85 lateral inches to the right of
the lower bolt hole center.  The right edge of the cutout is 3.15
lateral inches to the left of the upper bolt hole center.  The total
lateral distance between the bolt hole centers is 9.00 inches. (note
this is not the diagonal center-to-center distance - it is the lateral
distance between extended centers.) 1.85 + 4.00 + 3.15 = 9.00

No idea when I will get the machining done -- the local machinist at
the field left this morning for a 10 day vacation.  Oh well.

Mark


OK Good info Mark. I was going to make a scale 3D but I did not quite
get around to it before I had to keep the wife happy and go off
to a family reunion in St Louis. I will get to it soon and see if
if there are some other alternatives. My damper plate is up at
the hangar. A lot also depends on what Jerry has done so far on
the beams he has. In the mean time just make the slot full width.
No problem.

Paul Lamar

Paul and Mark,  I am still thinking about what to do.  Making a
single cut out large enough to fix the problem is the direction I am
leaning.  I happen to have some .125" x .5" 304 SS strips that I just
placed on the S-beam in the outline of the cut out.  I liked what I
saw although the .5 height of the strip might have to be reduced
slightly to clear the counter weight.  It go any further, I have to
remove my engine from the engine mount.  This I am putting off  until
I get the ignition coils and wiring  installed.  For some reason MSD
dropped my order and I  had to reissue it yesterday.

Anyway,  framing in the opening around the flywheel will probably
look cool and be stronger than the original.   Jerry

How many beams do you have with the spacers welded in Jerry?

Paul Lamar


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