Hi !

I would like to build a custom muffler for my P40 so that my .91 glow engine really pufs through the scale exhausts...
First, I plan using a macs header as a starting point, then solder a custom made muffler made of copper (or brass ?) sheets (hand cut and then soldered).
My questions are : What is the best soldering technique that I should use to achieve this ? How can I avoid leaks ? Is copper better than brass ?

I have enclosed a poor drawing of my future scale exhaust.

Thanks a lot for your help !

<<...custom fullfer...>>

That was a trick to make us look, right???

Thought I was about to learn something...

OK let's be fair, I 've put it back.

I'm currently doing a review of the Hanger 9 P-40 for RCU, using a Saito 100. I'm putting a custom made exhaust exactly like the one you describe. I got it from [link=http://www.keleo-creations.com/P-40%20Warhawk%2060/exhaustman.htm]Keleo Creations[/link]. I spoke on the phone with Calvin, the owner, for quite a bit. These custom exhaust systems are all that he does, and he does a great job. I've got mine in and I can't wait to finish the plane so I can hear this exhaust.

Give Calvin a call and he may be able to make an exhaust of fit your motor.

Hope this helps.

Thx RCKen for the tip. These guys seem to make great products indeed !!! I couldn't resist posting one of their creations :

[link]http://www.keleo-creations.com/P-40%20Warhawk%2060/images/thumb5-5-P-40.jpg[/link]

But as I'm not that wealthy, I can't afford a custom build setup, I'll have to make it on my own ... I'm a builder

I would suggest using silver solder as it needs a higher temperature to melt (thus your engine exhaust heat will not melt the solder especially a four stroke) copper tubing is great for this job but when i t comes to the the exterior bit try using brass tube as it is lighter i have a magazine somewhere that has the guide to doing this will look it out and scan it in for you

I built custom mufflers for a Henschel 129. Power was .46 two stroke and exhausted through functional scale pipes. I used thin steel sheet metal and silver solder. I also made tabs that folded around each joint and put in sheet metal screws to hold the joint while I soldered. If you make a good fitting joint the solder will flow and create a seal. I did a lot of experimenting to get the required back pressure and sound deadening. After the design was perfected a friend in the sheet metal business welded lighter mufflers from aluminum sheet. I also utilized a combination of copper pipe and tubing fittings for some of the bends.

see if you cant cut an aluminum one and take it to a welding shop to be tig welded together. its not gonna cost you that much, and if your lucky the welder will be so interested in the project, he'll do it for free(or maybe a couple flights on the buddy box).

i know the last time i had a rivet replaced in my boat, he welded it for free in exchange for a bag of fish

then again this is the south, and we tend to be a bit laid back on things

tell you what, ill talk to a friend, and i might be able to get the welding done for free for you(i love friends with tig welders.)