tuned pipe silencer/filter

[_laxmasta2039]

hey guys,

with all the sound decibel regulations, along with the ever-present problem of pollution, i was wondering if anybody has seen,made,or heard of a screw-on [or some type of detacheable] silencer that would also work to filter the outgoing exhaust......i was thinking that it might work to put a RC car inner air filter [not the huge foam outer one]

on the end of an extra long stinger.....anybody wanna cast thier two cents?

joe

 

[Hammerhead]

Hey laxmaster!

If you are just playing, it might be okay, but if you are racing, I wouldn't advise it. If you run your pipe cold, a lot of unburnt oil builds up in the pipe. If there is no where for it to go, then your performance will be seriously degraded. There are a lot of other facters involved with pipe tuning that I don't know the terms for that will also be effected. Keep in mind that a lot of the ingredients in RC fuel are enviromentally friendly anyway. If you use Klotz based fuels, you will be safe. You can pour the stuff on grass, and it won't kill it.

Noise can be regulated within the limits of most racing organizations with pipes and silencers on the market. For example; if you use a macs quiet pipe with a prather silencer, you will be within the limits.

Hammer

 

[_laxmasta2039]

prather silencer.....didnt know they made one.

is it detacheable?

joe

 

[wswatzell]

Joe,

Prather makes 2 sizes that i know of. here is a link to tower hobby's site for the 7.5cc (.45ci) size

http://www2.towerhobbies.com/cgi-bin/wti00...p?&I=LXDR49&P=0

it is removable, but it is not a screw on. it uses a pipe clamp to hold it in place. just loosen the clamp & it should pull of with a little effort.

Wade

 

[_laxmasta2039]

wade,

i saw the one on tower [after hammer said prather makes them] but my engine is a .18....... do you have any experience w/ one of those? it looks like just an extension of the stinger...... if so, it wouldn't be that hard to home-make one.......

joe

 

[Hammerhead]

Hey Joe! If you think you can make one, you should try. Even if you aren't successful, it will be a learning experience.

I would recommend using an empty can of spray deoderant. If the can is aluminum, it will be plenty light. Take a pipe, drill a lot of small holes in it, and that will be the guts to it. then shishkabab the can with it. You can cut slots in the pipe that will close down on the stinger with a hose clamp.

Those Prather silencers are a dime a dozen. I would buy one and try it out if you are worried about the aestheticss of you boat.

Hammer

 

[Mad Max]

If you want to make your own look at this,theres a muffler there made from WD-40 can

http://www.modelgasboats.com/Home/Archives...2002_issue.html

 

[Propjockey]

I made this muffler years ago as an experiment on one of my airplanes--worked awesome. I used it on .25, .35, .40, .46, and a .76 engine, and it worked well on all of them. Now I use it for late night break-ins and tuning, so the neighbors don't get too upset with me!

I used a length of 1/2" aluminum pipe with several small holes drilled in the end. This was inserted into a Ronsonol lighter fluid can that had holes drilled in the front end of it. Then the assembly was inserted into a mousse can that had the back end cut to let the exhaust out. JB Weld holds it all together and I stuck the bottom of a Coke can on the rear to clean it up. A piece of 7/16" silicone tubing was used to attach it to the outlet of the factory muffler.

The exhaust travels through the pipe, out the holes and into the lighter fluid can, changes direction and travels forward. It comes out the holes in the front of this can and into the mousse can, changes direction again and travels back the length of the mousse can and out the rear.

The funny thing is that it worked better on the bigger engines. On the .25 and .35 you could still hear the engine, but not much. On the .46 and .76, the only noise was what came from the prop. In the air, they were ALL so quiet (with the exception of the .25), I couldn't tell when the engine died!

 

[Propjockey]

The back end. (looks like a SuperTrapp for motorcycles)

 

[wswatzell]

Joe, i don't have any experience with them, but i would try to make one myself, it sounds like a fun project.

Wade

 

[MikeP]

Propjocky,

Thats some nice work on that muffler.

Hey Laxmasta,

Most .21's meet noise specs. without mufflers. You should be fine on an .18. But if I had one like the one Propjocky made I would use it just because it's cool looking.

-MikeP

 

[_laxmasta2039]

thanks all....

the reason im worried about noise regulations is around here all the good ponds are at parks or in picky "gated communities", keeping noise to a minimum could be the difference between having a place to run and not. then again, if i can get permission, i think a silencer might find it's way into my field box if i get the urge to hear the sucker roar [ok, i know, it's just a .18] ;D ;D

dime to a dozen......the prather ones one tower are 20 bucks apiece [for a 7.5 one] i think i'll try taking a small can of wd-40 or something small like that and try one for myself.

i'll post how it goes,

joe