ORIGINAL: frets24

Your work looks very nice and I like the idea of your exhaust manifold. I am sorry to tell you that I don't think it will hold together with the type of solder you are using.

I am a plumber by trade and it looks as if you are using a standard low temp antimony solder commonly used for joining low psi and low temp house pipes. You need to be using silver solder or brazing solder...it comes by the stick and not on a roll. It needs the copper to be heated to a bright glowing red to use and does not require any any paste or powder before solder/brazing. You can build the same thing, with the same type fittings, but it will need to be new parts...you can not braze over the parts you have already soldered.

What you have already built may last a few flights using a 2c engine; it will come apart very quickly if used with a 4c engine.

Your solder may be a different alloy in Czech, so check it out well on a test stand before commiting it to the plane...it may hold up as it is.