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S1-11-b Slave Strut Question

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rbilu

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Have been making the parts for the slave struts. Have had to make a fixture for tapping the bushing that goes in one end of the slave strut (.3125 x 24) as per plans and then back drilling to open the last 2.125 up to .375. The bushing receives the clevis depicted above.

Looking at the wings, my slave arms are attached to the aileron hinges and tightened, measurements taken etc. But looking at the arms and their directions of travel, it is a mystery to me how the heck this slave can work at all. The 3 degrees of dihedral in the bottom wing and the 7 degrees of sweep in the top make for some poor alignment of the directions of travel.

One end of the slave strut is a channel (fork) with a .375 opening and two gussets laid over it. It's welded to one end of the streamline tube. But the arm and KP3L bearing are .250 thick. (a good bit of slop there if no washers are added when inserting the bolt) On the other end, the clevis has an opening of .250 as per plan, a close fit.

I don't see anywhere in the plans where it shows me which end of the slave strut goes where. I suspect the clevis goes on the top wing aileron and the fixed portion on the bottom as the bottom arm would then try to keep the slave aligned with the direction of flight??? The top arm is the one with the peculiar travel path and allowing the clevis to turn as the ailerons are applied might make this all work.

There is no angular movement in the bore of the KP3L bearings that I received, which it looks to me like will be necessary??? Is this setup the same on the S1 and 2's???
 

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