Added a Ply bulkhead under the stock one in the Arreaux. this is from the existing coupler side after I've installed the retention allthreads and nuts. You can see, I added a second set of nuts to provide support for the end of the altimeter tube as it doesn't reach to the end. *

This is a 3.125" section of 1.52 BT, with a 1/8" bulkhead epoxied into the end flush. I added washers so that this will slip down on the bolts thru the existing bulkhead *

Inside of the Altimeter bay with altimeter mounting board *

With the mounting board dropped in the Altimeter bay, the perfectflite and battery just fit *

1.52" BT fits perfectly inside of the 1.9" coupler. This image from the coupler side of the payload section *

4-40 bolts with locknuts are inserted from the existing payload section, thru the existing bulkhead. There is about a 1/2" open air section between the existing bulkhead and the new one at the end of the 1.52 BT. This is where I'll put the terminal blocks for the ematches, You can also see the cap about to be installed. The outer bulkhead matches the outside dimensions of the existing coupler. The inside coupler matches the inside dimensions of the 1.52 BT *

Cap on, whole assembly ready to be slid inside existing coupler
Another view
payload section with new screw eye and kevlar shockcord. You can just see the lock nuts on that side
Slid together and ready for nuts and washers

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Another view *

Payload section with new screw eye and kevlar shockcord. You can just see the lock nuts on that side *

Slid together and ready for nuts and washers *