Here is another fail safe design. The Brits invented it almost
100 years ago. It was used on Brooklands race cars. It is called
the Fishtail muffler.

The flat panels must be beefed up or they will resonate and crack.

The last one is a tuned tangential with Fishtail.

Paul Lamar ...No rotor no motor.


Ed Anderson tried a fish tail muffler on his RV 6 about 5 years back.
Said it disintegrated within a couple of flights. I don't remember
whether he reinforced the panels though.

Mark Wrathall

Ed just squashed the exhaust pipe flat. See the last two jpg's.
That is not a true fish tail muffler as the exit area is reduced
compared to the cross sectional area of the exhaust pipe.
That speeds up the exit air velocity and adds more back pressure.

Also it was not reinforced and one or more designs
had holes drilled near the squashed ends.
Consequently it failed where the pipe was over stressed in the bend and
the flat parts probably resonated.
-- 
Paul Lamar ...No rotor no motor.

Paul,
Here's my GIF on the Fishtail. I haven't sorted how to trim yet.
George (down under)

You almost got it George. Save this on the hard disk. Open MS Paint.
Load this into MS Paint. Move it up and to the left. Then use the line
device in MS paint to detect the lower right pixel counts on where you
want to crop the picture. Look to the lower right to see the pixel
count change as you move the cursor around with the mouse. Note the pixel
count for the right lower crop position. Then select Image > Attrbutes. Enter the
noted the pixel counts in the width and height boxes. Select OK.
Then save as jpg and email that. How old is that version of A cad?
-- 
Paul Lamar ...No rotor no motor.

2004 Paul,
George ( down under)


I am amazed it does not put out a simple jpg.
I guess that is why it fell behind Rhino and Solid Works
and a zillion others like Turbo Cad..
Back about 20 years ago it was the dwg program of choice.
I started with version 4 round about the middle of the 80's
and used it up until the sluggish Windows version came out
around 2000.
-- 
Paul Lamar ...No rotor no motor.

Paul,
It does a JPG , but when I look at it , it's very poor quality and some
lines are missing. Then again it might be just XP trying to read it.
George ( down under)

It is. That is a problem with the XP viewer. It tries to scale everything to
the same size doing a bad job in the process.

Try loading it into MS paint to get a true view at the actual size.