Engine mount tube size and thickness??

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I’m building an experimental Bush type plane. I’m ready to fab the engine mount. I’m using a 320A2B. Which is the conical mount. My question is this -
A - is .750 x .049 wall standard ?
B- What size and thickness tubes for the through bolt end of things. As in where it attaches to the firewall and where the rubber bushings bolt to on the engine side. Thanks.

 

[Racerx]

No clue on exact sizes. But I strongly recommend chromoly, and a tight fit up is absolutely paramount.

 

[Bell206]

A - is .750 x .049 wall standard ?

Not that I'm aware of. Tube diameter and wall thickness is factored of a number of things.

B- What size and thickness tubes for the through bolt end of things. As in where it attaches to the firewall and where the rubber bushings bolt to on the engine side. Thanks.

Same. It depends. Are you fabricating a one-off custom mount? Perhaps give an engine mount fab shop a call for some input or try and adapt an existing mount?

 

[Dana]

For the bolts, whatever is a close slip fit (you may have to drill it out) on the bolts with a reasonable (1-1/16-1/8) wall thickness. For the rest, whatever is strong enough based on the calculated ultimate loads. Typically long column (Euler) buckling is the critical case.

 

[Stewartb]

This may help. https://www.supercubproject.com/drawings/