Homebrew muffler options
 

I have been making puck shaped muffler out of small aluminum gas cylinders flat stock and weed wacker handles. I copied it from the type that are sold for Ryobi conversions. The flat stock disk is lathe turned to put a shoulder that a single drawbolt in the center holds in place. Imagine a tuna can with bolt though the center of the circle. The piupe ids usually stuck in radially. That all looks great and works on the ground. When I fly it gets hot enough then the pipe falls off sue to the solder melting.

So, how much do welders charge to TIG a bead around a pipe? ...ballpark.

Next idea is to braze up steel tubing an use the Briggs and stratton type cigar mufflers. Somone sells something that looks simmilar and they call them sunfflers. This option has me worried about the extra weight hung from the jug screws. If I did a pits style that would be a lot of weight far from the jug screws. I imagine that between the vibration and G-forces it might not end well.

Anyone have any neat ideas on homemade no tig buffler options? I am fixing to fly my BME 50 clone.

RE: Homebrew muffler options
 

I am building mine from 1 1\2" or 2" aluminum sguare extruded channel. make it as long as you want and cut exhaust opening to match engine, then place tubing inside to support two bolts clear thru. cut squares for each end that fit tight and use aluminum braze (ace hardware has it). It will take the heat with no problem. Then out the top drill two holes for 7\16" tubes for exhaust opening. Work great. Have 28cc, 31cc, and 40cc all with this arrangement.
The channel should be 1\16" wall for light weight. Mine all weight around 3 oz.
Hope this helps.
Jack

RE: Homebrew muffler options
 

here's what I do, this style Poulan is super simple to modify the stock muffler as it's only held together with the springs, just take out the two baffle plates in the middle, weld up the stock outlet and grind it to look like it was never there (takes a little time with the Dremel), cut a hole or two for the outlet tube(s), I use tube from a folding camp chair, and enlarge with a chainsaw file and weld in place from the inside for a clean look. I use the MIG welder at work and just use a LOT of tack welds to do it, I've done it with my little 110v arc welder turned way down with 1/16" rods but it's a bit messier and takes a LOT of patience.

RE: Homebrew muffler options
 

Rangerbob, I noticed that you have long stacks on your mufflers. Have you found that helps with scavenging, or is that mainly to clear a cowling on a plane?

RE: Homebrew muffler options
 

I set those up to sell, so I made them long so the buyer could do what they want... I haven't done much testing or anything. they aren't quite as long as they look, about 4" max, probably an inch above the spark plug

I need to get a pic of the one I set up for my giant trainer, they stick out the side of the muffler swept back at an angle

RE: Homebrew muffler options
 

I have been using bernzomatic AL-3 rod. I guess that is aluminum braze. It melts when you get after it with a big engine. Seems fine for the little ones though.

Mufler?....Would that be mooo-flier? I am sure some you have realized that I am dyslexic. Sometimes the spelling/seeing issue is compounded by a few cold ones. :)

RE: Homebrew muffler options
 

A bit off topic, but .....the piece of metal that the engines are sitting on in your photos.....looks a lot like Butler MR-24 standing seam roofing? I was a Butler dealer for 30+ years, and it just happened to catch my eye.

RE: Homebrew muffler options
 

that's actually the tailgate mat on my Ranger :)

RE: Homebrew muffler options
 

Sorry....forgive the stupidity....or blindness....or both[:o]