I've not started cutting metal from the inside of the engine yet, but have made an exhaust...

Flange from stainless steel sheet - took forever to cut - never again...
Bend from Krumsheld - I think - left over from another job.
Canister from the Pound Shop... Salt and pepper containers. There's a baffle 2/3rds of the way down the can.
Silver solder and pop-riveted construction.

4 1/2oz lighter than the exhaust that came with the engine, and has given me an extra 200 revs. A little quieter too I think.

As long as it stays together - my track record isn't good when it comes to making exhausts. It had 3/4 hour in the air today and is still in one piece... I'm keeping my fingers crossed.