If you think there is 10 lbs to save in Tracy's PSRU, that's huge
 considering CG and all...If someone is willing to get the necessary
 components that can be whittled and you direct in the ares to be machined,
 I
 would be willing to do this for a very small sum to cover the tooling and
 possibly the fixture material, about $200.  NO other machine shop would
 touch something like this for under $1000 .................

 thanks

 jeff

 I'm interested! My psru still in the crate.
 C. Smith


 Here is another way Jeff. We rejected this idea a few years ago because of
 excessive cost. The cost on NC milling has come way down recently.

 The big weight savings is it combines the schertz beam with the adapter
 plate. A schertz beam alone weighs up to 9 pounds depending on the length.
 Bob White tested it for us in a crash.

 The right side can be much shorter to accommodate a rad on the cool side
of
 the engine. I'll do a suggested dwg for you. It is a half inch thick.
Jerry
 Hey tested it for deflection and Jarrett did an FEA.

 Paul


 I will have bottom Radiator, and what looks like 25.98 between barry
 centers
 if I read the drawing Paul made of the mount for me correctly.
 So combo plate, then some shaving on the housing, what, 19 lbs saved????
 8-D
 C. Smith

 Not quite that much as some goes and some stays. I would say 15 pounds is
 possible.
 We should standardize on the asymmetric mount as it can be used with a
 bottom rad or a right side side rad.

 It will look something like this. I'll have to redo that zenair dwg if we
 use this plate.


 Paul Lamar


 I think I like this method. The strength is proven in the crash test. Can
 you proceed with a new drawing for the Zenair mount?
 Jeff, can you make these if Paul sends you the cad file? Cost to produce?

 Paul, what was the depth of the cutaway for the gear housing in the image
 Tracy-PSRU-10-2000-dwg, and how thick should the flanges created be? Can
 the
 RD-1C be safely disassembled by an average skilled person?
 Jeff, with numbers from Paul, can you make the modifications to the gear
 housings? Cost to modify?
 I bought the 4130 sheet for the S-beam, but much of the cost is in the
 fabrication, so I can eat $46 in material.
 C. Smith

 The max thickness on the housing should be 1/4 inch everywhere.
 Tracy got carried away and made everything a 1/2 inch thick or thicker in
 some places.

 The Ross gear box was 5 or 10 pounds lighter.

 Tracy's older 2:17 PSRU comes apart rather easily. You take out the 10-32
 screws holding the front cover cover on and the large ball bearing should
 come right out.
 On mine Tracy glued it in with red RTV. Then you have to unbolt all the
 long
 1/4 28 screws holding the unit to the adapter plate.
 After that it should fall apart. As I recall on the 2.85:1 the ring gear
is
 pressed and keyed into the housing so you don't need to remove that. Power
 is taken from the planet carrier. Ignore the green and red parts. Those
are
 just my idea for a built in torque meter.

 Paul Lamar


 Jeff,

 This may or may not help you. It is looking at the adapter plate from the
 prop point of view with a dual set of dimensions. The radial set came From
 Tracy.

 BTW guys I suggest everybody get a copy of free Q-Cad as it works on both
 Windows and Linux. That way I can send you 3 view 2D dxf dwgs and you can
 dimension them yourselves if you are interested or need to make the part
by
 hand.


 Paul Lamar


 Other wise I need to do a lot of extra work as modern 3D cad dwgs don't
 normally have dimensions on them. They are drawn to exact scale and they
 can
 be loaded into a NC Mill without anybody reading the dimensions.

 Paul Lamar


 Q-cad installed and running, but it's not really free. It terminates at 10
 minute intervals, then after 100 hrs total for good. However $35 isn't bad
 for the ability to get some stuff done and not have to take up time that
 could be better spent upgrading Kasauga mills, or designing new stuff for
 rotary aviation.
 C. Smith


 Thanks Craig. I think it is well worth the $35 for a 2D cad program.
 Seems rock solid. I'll send some dxf's for it shortly.
 In fact try this one and see if you can dimension it.

 Paul Lamar

Paul, I bought a cad program on e-bay for $24 called  DesignCAD  3Dmax v18
just to try out the rendering part. It does 2D drafting and 3D solid
modeling, 3D rendering and animation and has a huge symbol library. I seems
easy to use with all the normal drawing commands etc.  They had about fifty
listings on this program recently.It has multiple import/export formats
including dwg and dfx as well as a lot of newer ones.You own it outright,
no
time or save etc limitations.

george grimes

Does it work on that 2D dxf I just sent.

Paul Lamar


Paul, The listed import file extensions are   DWG,DXF,IGES,WMF,HPGL,and
XYZ  . There is a setting for 2D/3D operation. I downloaded the rear housing
dxf file and lost it  on the hardrive. I saved t twice because it showed 174
KB and saved as 22.4 KB    I will eventually capture a dxf file  on the CD
drive where I can find it and try it out

george grimes

Well Design Cad does not work on Linux so I can not try different files
in case someone has problems. Q Cad works on both. Like Office, Thunderbird
or Firefox it is a cross  platform application with complete file compatibility.


Paul Lamar