I'm new to conversions and wanted to start a new thread for mufflers. There seems to be a good supply of ignition systems but as of yet I haven't seen a muffler supplier. I know there are tons of conversions out there and wondered if someone has capitalized on the muffler area for larger engines. I am personally looking for mufflers for a Poulan 60 (Gillaroni cylinder) and Homelite 300, both are saw engines. It would be nice to throw the stamped steel monsters out for something smaller and lighter. Or does everyone just make their own.
Tim

There is a company, (Abell, I think) that has a stock line of mufflers. If you give him dimensions or a tracing of your exhaust, he will finish machine one to fit your big engine. The prices are reasonable.

Ask rcign1 ?

Good luck,

Jim

B&B or bennet will custom make one at no extra charge the last one I bought was 35.00 shipped to my door.

Darin

Ive been making up some mufflers for myself and some friends. We have been trying to get away from the "diverter" type of muffler and go to a seperate header and a large volume muffler for less noise without a loss of performance. I have a Poulan 46 conversion I plan on trying some things with. When I get some RPM/DB readings Ill be sure to post it.
Adam

I've been talking to the Abell answering machine for about 2 months. Not a single returned phone call from them. I've called them about 6 times in the past 8 weeks. I've left messages upon messages. Zip- Nadda- nothing.

Tell me about it. I've been having a tough time finding good mufflers for conversion engines. B&B and Abell are about the only sure bet, but they are really more exhaust diverters than real mufflers. Most of the aftermarket muffler shops don't much care to cater to our needs. We are either viewed as too cheap to pay for good stuff or too small volume to justify the tooling cost. As much as I hate to admit it, there are probably a lot of truth to both.

The bright side is that engine conversion seems to be a fast growing "sport". Some of us actually enjoy it more than flying planes with them - hey, you know what I'm talking about. So may be in time, things will start to get better.

mousse cans on my glo engines make good power but they don't seem to hold up to the vibes and heat of the big gassers. i love the big canisters sold for gas engines but since i destroy (crash) planes and engines at an alarming rate i cant see myself paying those high prices. i have some alternatives to the wimpy mousse cans that i'm going to try some day.
the big red can is from a dissposable fire extinguisher, measures 9"x3" , weighs 5 oz. is heavy duty alum and has the same 1" neck as the mousse cans.
the other can is also heavy alum has a lrger neck and came from an automotive glass repair shop, the black glass primer from sika.

Dont give up. Here is a pic of a project I just finished for a friend of mine. This isnt a conversion but it shows what a couple of stubborn modelers can accomplish when they wont settle for what is available. He designed the mufflers and I welded them up and fabricated the headers.

I dont know if there is a market/demand for the conversion enthusiast but I have a demand for a Poulan system and possibly a Ryobi setup that I will be starting on next.

So if anyone has any Ideas for some posible configurations and would like to share them please do. Ive considered a firewall mounted muffler with a header running to it or even a more conventional header/cannister setup.
Adam

Being a tool freak, I look for every excuse to buy more tools. Heck, I just bought an $800 pressure washer to clean mildew off my soffits. Still, I can't bring myself to invest in a good MIG or TIG welder just to do RC mufflers.

Aneat, my vote goes to a "wrap-around" style muffler for the Poulan 46cc or any of the Kioritz (Echo) engines. I also like the idea of a separate header and firewall mounted canister muffler. The "in-fuse" canister setup is great if you got the room for it, but not every fuselage lend itself well to that kind of modification.

I use the inner piece of Quadra or US Engines muffler and make a 3/32 aluminum plate to go over the back of it. Cut the pipe or pipes out of the back piece, cut holes and braze or weld pipes to the front piece. No power loss and just as quiet. Now it will fit flush to the firewall which was always a pain in the butt. Will fit other engines as it has a small inlet hole to be cut bigger. Wish I could figure out how to make pictures come on.

Volfy; I had a larger Tig welder years ago and have always been into welding as a hobby. I ended up selling it and was fine for a few years until I had a bad experience getting an aluminum swingarm welded at a local shop. Poor quality work and way overcharged. :angry: So I bought one of the new smaller Lincoln square wave Tig setups and love it. I do a lot of other stuff with it and have just began to get into what I may be able to do for RC. Ive been flying smaller stuff but all the possibilities with this conversion stuff may get me into bigger planes :stupid: After looking at mufflers I thought I could do something similar.
Adam

Here is another with some potential. These are from water filter cannisters where I work. Every couple of months the change them and one is on every drinking fountain, ice maker, coffe machines etc. They are aluminum, 3" dia and approx 14" long with one end closed and ~.050 thick
The bad part is they have some kind of plastic lining that can be a pain to get out

Aluminum tubing this size isnt to expensive but every little bit helps.

If someone has access to some type of CNC machining getting the flanges or any other ends/fittings made would be nice. I can bend the tubing and weld everything and I even have a lathe/mill setup, but making the flanges is time consuming for me because everything is done manually.
Adam

Adam, do you think a TIG is much better for welding aluminum? Lincoln has a MIG that supposedly can do aluminum, but perhaps not quite as intricate as what you can do with a TIG? Sooner or later I'll find enough reasons to get a welder.

I like the Tig better for several reasons. I originally bought it to weld chrome molly steel and it does a much nicer/cleaner weld for that. Ive seen some nice mig welds on aluminum but im not sure how it would do on the thinner stuff. Im pretty sure you need a seperate cable for doing aluminum with mig because the wire tends to gall up feeding thru.
Another thing when welding with the Tig there is no smoke, sparks or splatter. I never was comfortable welding in a shop with balsa wood and saw dust in the cracks and corners with sparks flying everywhere. And if you have ever mig welded you know the sparks and splatter really flies.
Its nice even in the winter I can go in the shop and weld for a while and there is no smoke to clear out.
Adam

Adam, I know what you mean. To do many RC related metalworks, you almost always need a good welder and a milling machine.

As for aluminum tubing stock, I've bought from http://www.onlinemetals.com/ before and their prices are not too unreasonable.

thinking of making my own muffler for a poulan 46. how did you make the header. i have a few ideas but would like to know what others have tried.. how much volume do you need in the canister to maximize output also? any suggestions?? thanks

Volfy,

I have a MIG welder that works very well for thin steel but I can't get near as nice of welds with aluminum. I bought the Argon gas, aluminum sheath for the gun, different tips, and aluminum wire. The MIG leaves a lot of splatter and will suffice for about 3/32" or thicker but for thinner stuff go with a TIG. I cut out the parts and have my friend TIG weld them and they turn out beautiful.

I have been contemplating buying a TIG welder and plasma cutter for my hobby interests. I have wanted to build mufflers and motor mounts for other modelers for years and would not be in it for the profit so much as the enjoyment of fabricating unique objects. If there is enough interest from other modelers, I will buy them and post a notice here.

Doug

I buy 3/4" alum. tubing from Lowe's for the outlet tubes, I use a pc. of 1-1/2" x 1-1/2" alum. square that you can buy at any glass place that installs "store front" type windows/doors, I make a 1/4" thick or whatever thickness needed to clear the side of the engine cooling fins, and use thickwall alum. ferrells inside to keep the square tubing from collapsing(?) ; cap off the end of the sq. tubing and you're done......works for me........

Duhawk; Look at another thread I started for the Poulan 46. Ive got some info on there about a header/muffler combo.

Doug; Ive done the same with my Tig. I bought it for my own needs and enjoyment and try to help out others when I can. I can usually barter or trade with other modelers and we can usually work out a deal without any money changing hands.

Of course money works too
Adam

i saw that earlier.. i have a friend with a welder.. what type im not sure but thats what he does for a living so im sure if i design something he can weld it for me.. is there any certain volume needed for the canister? what works best? also what did you do to match the start of the header to the engine.(where it screws in) does the poulan have a round exhaust port? and one final question what type of performance would you get with a 46 poulan on say a 15-16 pound sport plane? looking for good vertical.. thanks

I made a flange for my header out of 1/4" aluminum. The Poulan has a sort of D shaped exaust port so it is kind of a pain to mill out.
As for muffler volume Im not sure what would be ideal. There has to be a compromise somewhere. I have been trying to go off the size of what is commercially available for a similar engine size. I think anywhere around 2 1/2" to 3" dia and 10" to 12" long should be close.
I plan on trying some different baffle configurations and even a cannister with no baffles and see how it goes.
Adam

how do you make the baffles inside? maybe its a stupid question but have to ask if im gonna try one on my own..

Thanks Doug. If I do get a TIG welder, it would be strictly non-profit too. In fact, I would have to make a boat load of mufflers and motor mounts just to break even. What it'd be good for is making stuff that are not commercially available - like accessories for these conversion engines.

Ive got the pieces for a muffler like the one I have on my Poulan.
When I get home Ill get a pic and post it. There are probably a lot of different ways it can be done.

The simplest explanation Ive heard is. "There are 2 things flowing thru a muffler, sound and gas. The trick is to attenuate the sound as much as possible without restricting the flow of gas"

Adam

Here are most of the parts for the muffler on my Poulan at the time. They are layed out pretty much like they go together. Exaust goes in thru the pipe from the right and into the chamber to the left and out of the holes in the tube. After that it goes thru the drilled round piece in the center. From there it goes into the outlet tube thru the holes drilled into it and out.

Pretty simple eh

Adam