Rebuilding a muffler

When my second John Deere track loader arrived the muffler was just laying on the turbo outlet broken off at the connection.
Someone had done some repairs on it more than once in the past And since the shell was still in reasonable condition I figured rebuilding it one more time was in order
Attachment 42568
Note how the inlet pipe only extended inside a couple inches, This was how they had repaired it the last time the inside of the muffler was just a hollow shell.
Attachment 42569
I punched louvers in a length of 4 inch exhaust pipe for the inlet pipe and to create some pathways for turbulence inside the muffler
first I cut a short slot in the pipe with a cutoff disk
Attachment 42570
Then using a punch and the louver die I made I set the louvers into the pipe
Attachment 42571
a look from the inside
Attachment 42572
After grinding down and removing every other tooth from an old circular saw blade and torching out the center I welded it and an end plate I made from a 1/8inch disk I had to the pipe
Attachment 42573
Usually there is so much carbon soot in mufflers that the easiest way to weld them is with a torch
Attachment 42574
All is left now is to remove the broken piece of the old muffler
Attachment 42575
Installed and ready for work