Originally Posted by Doug Sams

Back when I was a kid, I recall seeing the coupler style mounts in the catalog. But none of my kits ever had one.

Upon becoming a BAR, I remember studying these more closely, and coming to the conclusion this was a case of over-engineering. Having the coupler tube spanning the gap from the aft centering ring to the front centering ring provided no extra benefit. If the rings were properly sized - ie, sanded to the right size - they would have no problem sliding into the airframe (or outer motor tube) - the coupler tube didn't add any functionality, IMO.

[Conjecture] That said, I suspect it was a vestigial construct. At some point early on, it was needed, but as the centering rings evolved, somebody (at Estes) realized one day that the rings were sufficient, that the extra coupler was superfluous, and they stopped using them.

(Here's where it'd be nice to get input from someone who was there back then )

Doug

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