o.k. so the hush power muffler is toasting up?

           best,

           George W

         George,

         "Melting" is more like it. After my initial 20 minute flight
     with the
         new HP2 muffler, there was "cake frosting" dripping from the exhaust
         pipe onto the hangar floor. The 304ss baffle was already
     beginning to
         scale.

         Mark S.

         Mark,
         Scaling isn't that bad a thing. I'm not surprised that your glass
         packing melted. That is to be expected at 1600 F Fine scale on the
         exterior of the muffler wouldn't be uncommon. Is the muffler
     becoming
         misshaped? Is the interior screening melting? I'd like to know
     as I'm
         trying to get all the stuff together for my 20B.
         Bill Jepson


     Bill,
     The airplane is currently down for some electrical mods at this time.
     So, I haven't flown again with the HP2 since the first short flight a
     few weeks ago.  The strange thing is that I didn't notice the melting of
     the fiberglass until I had shut it down.  It could have already been in
     the process of melting with the fiberglass being blown out the exhaust
     as I flew.  I noticed the goo on the hangar floor after it had been
     parked for 15-20 minutes.  It is amazing that it was still hot enough to
     continue melting the glass long after shutdown.

     No, the baffle inside the muffler hasn't melted, but it sure looked like
     it had been through the fires of hell.  We'll see how it holds up.

     My recommendation is to either place the muffler 3-4 feet back from the
     exhaust ports, or build a muffler from inconel or thick 321ss.  Another
     option would be to turbo-charge and forget the muffler.

     I'll report back after I fly again.

     Mark

     Is the Hush Power muffler inside the cowl Mark?

     You have room in there for a huge tangential muffler with
     a JB Wagner thick wall 304 SS Jerry Hey cool tube running down the
     center.

     You may need to add a patch to the outer or inner skin where the exhaust
     directly impinges on it.

     Paul Lamar



Paul,
I was hoping to locate a piece of inconel tube/pipe or at least 321SS
pipe.  I'm getting tired of building mufflers only to have them
self-destruct in a few hours.  From what I can tell, the Wagner tubes
are holding up.  I hadn't considered using a larger diameter "handrail"
to fabricate a tangential muffler.  I'll check into that.

Mark

P.S.  My tig welder is broken.  ;-(


Too bad. That is bad news. I am sure Jerry will weld something up
for you.

Some heavy duty sheet metal shops can roll up 304 SS into a large tube or perhaps
two 180 degree sections of  large tube. Same goes for Inconel sheet.

0.065" 304 SS would probably work but .090" would work for sure. I don't
thing Wagner has hand rail in eight or ten  inch in diameter.

Paul Lamar ...No rotor no motor.

You could do a spin tec type muffler or maybe use rock wool or
steel wool instulation type packing.

Clifton

That stuff goes away immediately :) The best plan is put nothing
in the muffler. Parts inside the muffler glow white hot.
You can stand behind this airplane and look down the exhaust
pipe and into the muffler when it is running. Even metal parts
are melted and spit out if they are too thin.

My 182 O-470 will (and has) spit parts out of the muffler eventually.
These are high continuous HP engines not at all related to
car engines.

Paul Lamar ...No rotor no motor.

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