Can you fabricate a muffler using silver solder, or will the exhaust temperature just melt the joint?

I think silver solder would be fine. By fab you mean use it to bond aluminum? I think the aluminum might melt before the solder. I don't have specific temps for silver solder but I know you have to get it very hot. Almost to the burning point of brass.

Silver solder will work fine but not on alum. You can use Brass or steel with no prob. You do need to use a good heat source, not a propane torch like you get at wal-mart, but oxy acetalyne or map. BTW the melt point for most Silver solder is 1100, there may be some older stuff around that will melt around 850 but it has cadmium in it and puts off some bad fumes. Most of the time you will find the cad free stuff.

Their's also some aluminum solder sold by welding supply houses that is great for oxy/acetylene use. I've used it to repair oil coolers and the like...has the flux in it...
But, everything has to be real clean and brushed before soldering...

Not likely the joint will melt, since most silver solders' liquidus is at or above 1000 degrees F.

Whatever base material you plan to use, J.W. Harris have a solder to do the deed, steel to steel, steel to aluminum, or aluminum to aluminum.

You may need an oxyacetylene rig to use the high silver versions, and you may find the smaller (but much hotter flame) easier to use than the whopping lower temperature flame of a propane or MAPP torch.

I just received a header from DA and that's exactly what they used (at least that's what it looks like). They just used some 90 degree elbows to create the right curves and welded/ soldered them together.

I have heard of alot of guys using it for gas engines, but I know for a fact with 4-stroke glow engines, the exhaust is hot enough to melt silver solder, what you need to do for that is braze it.

Patriot

Brazing rod is certainly cheaper

Thanks everyone for the input.

My silver solder knowledge is from investigation only. Silver solder comes in a variety of melting temperatures starting around 800 degrees F. and going to 1800 degrees F. Jewelers will refer to silver solder as soft (1100 F.), medium (1300 or so) and hard (1800). Using silver solder is really brazing. A conversation with a Jeweler might get you started in the right direction. Stay-Bright is known to melt at exhaust temperatures.

However I did purchase some soldering rods (Model AL-3 4043 Aluminum Soldering Rod) from Lowes and was able to stick some aluminum together with a propane torch. The trick seems to be in understanding the melting point that cannot really be seen. Cleanliness is also a problem. And I found clamping to be a problem. The AL-3 has a working temperature of 700 to 750 F, which should be enough for exhaust work.

Let us know what you find.

can you tell me how to repair a pitts aluminum muffler nose over and cracked one of the exhaust tubes jb weld weld rods ??? thank

I have not had much luck with J B weld on engine parts.

Welding of any sort requires a certain skill/knack.

The quickest and cheapest way to get the muffler repaired is to take it to a welding shop that specializes in aluminum welding. Unless of course you just want to experiment.

Ed S

Don't forget, some of the products sold as Silver Solder are regular tin-lead solders with about 2% silver added. Their melting point is about the same as regular tin-lead solder. You usually find them on racks at various types of non-specialty stores.

I'm not much good with metal work but after talking to a friend who does this for a living, he modified the muffler on my G38 with this secondary muffler. It's a Briggs and Stratton lawn mower muffler. He told me that brazing was really the only way to go. The two mufflers are stamped steel but the joining pipe is brass. He silver brazed them for me. Apparently, there are brazing rods with different metal contect but the pros know which one to pick each time.

How much quieter is the engine with the second muffler on it??

Don't know yet. Haven't fired it up yet

A lot of article have been written in the mags, and ususally seem to indicate another 4 to 8 dB sound level drop.

Frank, I have fixed quite a few of these in the past. Get it real clean and find a buddy that can tig weld it for you. Do not grind away where it broke, let the welder do any surface prep he wants or needs. Just get it real clean.

The best way to fix alluminum is tig weld it.Thats what some welders and I at the place where i work do.Whenever i got alluminum to weld-take it to work LOL.