I am getting ready to tack weld up my motor mount.
I was lining up the engine with the fuselage. I had leveled the fuselage
and made sure the firewall was vertical using a carpenters level. I had the height
of the engine about right and it was perpendicular to the fire wall.
I knew this because I measured each side of the motor plate back to the firewall.
I also had the engine leveled fore and aft and side to side.

Then I said to myself; self, how can you be sure the engine is centered from side to
side? Well I could put up a string on a couple of posts and measure over to the center
of the fuselage fore and aft to make sure the string was parallel to the fuselage
center line and then measure over to the engine e-shaft center line.

Then all I would have to do is wiggle around under the string lie on my back and try
to tack weld the motor mounts parts without moving anything. Ahhhh???? 
Heck it is hard enough for me to tack weld when I am in the normal position
and the part is on the bench in front of me.

Another way of doing it is hang the engine vertical from the ceiling over
a firewall mock up on the floor or on the bench. You then must balance the engine
such so the center line of the engine is perpendicular to the firewall mock up.
Not an easy thing to do. Ahhhh???? 

Then I thought..... I think I will go back to plan A.

Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

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