Giant Muffler

[dawjr32223]

Hey,Guys. Needed a muffler for the new dust collector installation, but it had to be a certain length - so I made one. Here's some pictures.

[geezer]

Where is the piece that directs the air/gas into the packing material and slows the it down to create a muffled effect, all I see here is a straight pipe type muffler which is not that effective, do you plan on using a piece in the middle of the muffler to redirect the air flow to the outside in to the packing material..

[dawjr32223]

Where is the piece that directs the air/gas into the packing material and slows the it down to create a muffled effect, all I see here is a straight pipe type muffler which is not that effective, do you plan on using a piece in the middle of the muffler to redirect the air flow to the outside in to the packing material..

Hey, Geezer. There is no piece (initially anyway) most of these types of mufflers are open flow-through just like a glass pack muffler for autos. Much of the sound pressure wave is diffused by being exposed to the "softer" environment, much like a room filled with draperies versus a bare one. The difference in sound level is dramatic, at least with the store bought ones and they are so much smaller than this one. The last one that I saw this size (this one is 7" diameter) was on a 15hp bagged dust collector and this one is only 2hp. Even at this stage I use the airgun to blow air straight through and the sound difference between in and out is appreciable.

[Jason]

The Borla muffler I used on my car is similar with the straight through effect. Well mine does have a curve in it, I can see through it and its still far quieter than not having it. My resonators are also this design.

[Tanh]

It's a resonator. Rather than a muffler in the classic term. Although some would argue that a resonator is one type of muffler, I disagree. The expanding gas should flow through the "soft material" slowing it down, hitting the outside wall and reflect back into the incoming wave. This theoretically should cancel out the waves and quiet down the sound. The materials and distances are carefully calculated for the particular application and are not picked at random from the air, as I had once thought. If there is a phase mismatch between the reflected and incoming waves you get some odd affects acoustically. Like a drone at certain RPMs where there's mismatch.

Actually the resonator is tuned for a certain frequency and very inefficient at most others that are out of it's range. Some cars like my volvo use 2 resonators to cover a portion of the low and high RPM bands. So to cut those out of a 6 cylinder turbo and maybe replace it with an aftermarket one will make the note loud and very annoying. But if loud and annoying is what you're going for, then go ahead. I've learned my lesson already.

[agent4573]

Almost every motorcycle muffler is made that way. They work fine, except for one or two specific rpm's that give you a drone. If you really want to quite it down you can put a baffle in the end. Basically weld on an end cap with a piece of tubing sticking about half way down into the muffler. Once the air gets to the end of the muffler, the end cap will force it to go back down into the standpipe to exit and increase the noise reduction properties of the muffler. Only downside is that it increases backpressure, but if its sized large enough that shouldn't be a problem.