Jerry Hey wrote:
Paul, in the attached drawing, it is clear that if I stick
with
straight line joinery with miters, exhaust sections running
at
angles
will lose capacity. I believe the solution is to use curves
instead
of
corners. Unfortunately, in my hands, drawing a curved line
in
cad
is
more difficult that cutting one out of stainless steel.
Could
you
model the pipe shape for me and send as an Iges file. Also
at
the
top,
near the muffler, I will need to put in a slip connection,
so
the
need
there is need for a short straight section. The exhaust
pipe
in
question leaves the muffler at 45 degrees and continues for
10
inches
and then in turn down for 10 more inches. The section is 4 x
1.75
inches. This is a real system that I will be building.
Thanks,
Jerry
Jerry Hey
j-winddesigns@thegrid.net
Is this a side view Jerry? If it were a front view the top
part
would
be
round.
Paul Lamar
Yes, side view. I want to have a curved version that
follows the
same
path roughly as the mitered version. I want to keep the 4 x
1.75
section constant through out. No round parts. If this
is a
lot
of
trouble, don't bother. I can lay it out in pencil.. I just
don't
know
how to get the computer to do it. Jerry
Something like this? The side view looks distorted but trust
me...
it
is
indeed constant area.
Paul Lamar
Here is a version curved in both front view AND side view along
with
the flats.
If you have not figured it out yet Rhino is amazing :) I could
never
in a million
years draw this with a pencil. :)
Paul Lamar
Can you place the flat side view on a grid so that I can pick up
the
full scale pattern? Thanks, Jerry
Sure or you can print that and scale it up so the width equals 4
inches.
Or I can send an IGES.
Paul Lamar
Here they are on a one inch grid.
Paul Lamar
Thanks again, we have decided to have the 4" exhaust pipe angle
back
from the muffler at 45 degrees for 10 inches and then curve down to
vertical for another 10 inches. If you can draw that on the one
inch
grid, I will try to find the graph paper. Jerry
Jerry, Thats what the double curve one does only it also does an S
curve
when looking at it from the front. You already have the flats on
grid paper
but here they are again. This is for the Tailwind as you did not
tell me it
was for the BD4. I'll have to check the fit on the BD4.
BTW Bob white, why the evap cores?
Paul Lamar
Opss I sent you the ones with the out the grid. Here is the grid
again.
If this is for the BD4 it will have to be redone anyway.
Paul Lamar
Why not one straight piece guys. A lot less work. You might find some
stock .049 SS tubing.
Does not have to be 321. 304 or some other SS would work here. Make
your life simple.
If not rectangular get round and squish it between metal plates in a
hyd
press to oval. I can give you a flat cutout pattern where the tube
intersects
the six inch round can.
http://www.tubemethods.com/
Paul Lamar
It may be that in some cases a straight pipe would work. In other
cases, we will have to have a curved pipe. Personally, I want no
part in building rotary exhaust systems for others with anything but
321. Also, I am sticking with .063 wall through out even though a few
ounces could be saved by going to thinner material. I want to get some
temp readings first, but I think this exhaust system, with cool tube,
will eventually carry a guarantee against ever burning out. Jerry
If the down pipe is stright you can bend it up in a brake and seam weld it.
Paul Lamar
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