I started off today by mounting the bottom cowling to see how my just-installed aft bottom baffle seals fit into the scheme of things.  They look good and functional, so I’m pressing onward, upward and forward!

I spent about 45 minutes going through another few versions of cardboard mockups for the lower right exhaust bracket before dialing the last one in that was good enough to import into Fusion 360 CAD.  After modeling it up I 3D printed a 0.020″ thick version and checked it out in situ.

It’s hard to show all the nuanced gaps and seams that need to be tightened up in pictures, and of course there’s the invariable relational and unintended consequences thing where making one mod negatively affects a different area of the part.  That being said, here is Version 1 that kicked off this very iterative process.

Besides trying to get the seams around the pipe sleeves as air tight as possible, my initial main concern was the “water level” of the bracket itself in that I want it to be very close to covering half the exhaust pipe, lest I get more than a half moon and the installation and removal of the bracket around the pipe would be difficult, if not impossible.  Also, the right outboard “bird beak” needed dialing in, as well as both screw hole positions.

I have a specific position on the lower left where I want the platenut to get mounted, thus the hunting and pecking with each version to get the inboard screw hole positioned correctly.  I still had more finetuning on the curves around the sleeves, and of course more dialing in the “bird beak” on the right.

Version 4 is very, very close to the final configuration I need.  Any more fine tuning at this level will simply be with a file after I plasma cut this bracket half out.  The seams are certainly close enough with the seams that very little extra filler rod material will be required to fill any gaps.  I’m calling this one good!

As a point of interest, here is all the versions of the lower right exhaust bracket in their reverse progression from top to bottom.  These each took about 12-14 minutes each to print, but also required a good 20 minute cool down before removing them from the print plate.  I’d say each one, including the markup and CAD work represents at least one hour each.

It was getting a bit late, but I wanted to get a few rounds of the top right exhaust pipe bracket under my belt before calling it a night.

Here I’m on version 2 (or 3?) of the cardboard bracket mockup (pic #1) before getting one good enough to import into CAD.  I then got the basic outline modeled up and 3D printed a plastic mockup (pic #2).

I essentially worked on filling the same gaps and problem areas on versions 2 and 3, I simply wasn’t aggressive enough on my gap fills on version 2 as required.  I also played around with the top inboard and outboard corner radiuses a bit too.

Here we have the final version (#4) for the night.  I actually kicked off the print and intended to check it in the morning, but curiosity got the best of me and I snuck back out to the shop to see how she fit.  As you can see, I added the mounting screw holes in each corner for this version.

I then marked around the perimeter of this bracket mockup and each of the mounting screw holes to ensure that there was enough meat behind it to mount plantenuts, and to also ensure that the bracket would cover the gap around the exhaust pipes. Looking good so far!

Tomorrow I’ll see how far I can get in constructing this right side bracket… if possible and the plasma cutting goes smoothly, I’ll try to get this tacked up to have James weld this sucker up along with the left outboard pipe.  A long shot, but I’ll try.  We’ll see.