I removed my Hushpower the other day to re-do the heat shielding around
 it.
  It's submerged and does not get enough cooling air around it. I used an
  aluminum heat shield and some woven ceramic insulation  with aluminized
  mylar, I don't know what that particular heat shielding is called, but,
 the
  aluminum burned through and the mylar melted. So, I'm doing a re-design
  where I have double stainless steel heat shielding with forced air going
  through the air space. Backing that up will be a layer of fiberfrax.

  But, back to the Hushpower. When I pulled it off, I shook it and it sounds
  like a baby rattle. So, I'm going to use a bore scope and see what's what
  with it. Hmmm....

  Brian Trubee

  Good idea Brian. Harbor Frieght has a cheap bore scope.

  I like the outer case design. I would cut it open and gut it
  and then weld it backup.


  Paul Lamar

 Paul,

 I tried one of these and it couldn't handle the heat.  Packing melted
 within
 the first hour.  (Maybe Brian could cut it open, stuff it full of SS
 shavings, and weld it back together.  The outer shell is made of 304 SS,
 but
 the perforated cone appears to be made of mild carbon steel.  It melted
 and disintegrated after about 25 hrs.

 Mark

 I am not sure I would put anything in it but shavings might
 be small enough to be spited out :)

 For the new guys this is what can happen if your cheap automotive
 muffler fails. This one caused a crash. The pilot lived fortunately.

 Rotary mufflers are best from Inconel if weight is important but
 .064 thick SS 321 is OK too for a 30% muffler weight increase trade off.

 Paul Lamar

 Paul,

What material was the baffle made of?  The Hushpower II has a cone-shaped
baffle.

Mark

Looked like mild steel to me.

Here are some fail safe ideas.


Paul Lamar