Hi everyone, I've set a time to meet with the CNC shop to discuss the
possibility of making the spacer. I've had some success with the 3/16
front and back plates. The plasma leaves a bit of rough edge on the
Aluminum, the thermal conductivity of the aluminum make it much more
difficult to cut a clean edge in thicker Al plate. See attached Pictures
of 3/16 plate cut and cleaned. Also see Rev 9 of the slide throttle assembly.
Paul, Any comments on the subtle changes to the attach flange or anything
else. Also will we be attaching the manifold tubes to the throttle with
silicon hose? How long should the tubes be, both port side and manifold
side? FWIW thats where we are. T.W.
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Couple of points on your 3D's Tom. Back to front.
A: The round flanges should be made tall rectangles
so they can share bolts at top and bottom. Also it is
easier to align the bolt holes when bonding the tubes into
the rotor housings. We trial assemble the engine with center,
front and back rotor housings and then bond the tubes in
with pre welded flanges while the inner plate is bolted up.
The inner plate serves as an alignment tool. Been there done that.
B: They should be near the end of the short
tubes that are bonded into the engine so they can be bolted to the
inner slide throttle plate. That is essential as the engine must be
able to be taken apart to overhaul of course.
C: The tubes are two inches in diameter so they should pilot in the
inner plate for alignment and inside smoothness reasons.
D: The outer 2 inch tubes or 180 degree bends can be welded to the outer
plate for compact size length and sealing reasons. Again they should pilot in
the outer plates for a smooth joint. A bit of sanding after welding
will take care of any protrusions.
Paul Lamar
If you are going to CNC the spacer, why not combine the spacer
with the inner (or outer) flange? Fewer parts, more rigid construction,
same amount of aluminum, and lower cost.
Bill Dube'
We are trying to keep the cost down and avoid using an NC mill.
A sheet metal punch can punch the 3/16 inch thick plates
for less than $10 each. My guess on on a 1/4 inch deep cavity
in aluminum plate would be several hundred dollars.
Then of course you would have a surface finish problem in the
bottom surface of the cavity.
The 1/4 inch thick spacer can be cheaply cut by water jet no problem
if Tom's friend can not do it cheaply. I have a source here in
Ventura county for water jet cut parts. They made some 3/8th inch thick
rotary engine intake manifold flanges for us about five years ago. I am
also not sure it cannot be punched.
Rigidity is not necessarily an advantages as the Teflon is quite
soft with a low modules of elasticity and will twist and bend to
conform.
Paul Lamar
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