I need more clamps to be able to drill all the 1/8 holes on the spars for the outer ribs without getting burrs in between the already riveted parts on the spar.
So I started on the aileron paddle mechanism for the folding of the wings. The 4 paddle blocks shall have two bearings each. The holes for these bearings are not honed or reamed to correct size, but are approximately 4-8 hundreds of a mm too small. I should have a reamer to do this, but a reamer this size costs 150 $. The drawings say use a reamer or sand it slightly. So I sanded and sanded and sanded... which was very fiddly because the hole is only approx 17.45 mm. Eventually I got them up to 17.5 mm, the bearings I measured to 15.52 mm, so this should be a nice fit. Here I really think Sonex should have reamed this part up to correct size. The block itself is (as all machined angle components) are really first class pieces of machined aluminium, and a press fit bearing is a close tolerance fit that requires reaming. Manual sanding and measuring and trying the pieces will do, but the amount of work is at least a factor 1000 compared to reaming. I thought about simply heating the blocks to let the temperature increase the holes, but Kerry (Sonex) said that heating should absolutely NOT be done, because the bearings will not stand the heat.
For the paddle mechanism, the drawings and the machined angled paddles does not add up at all. The machined angled parts have two identical inner paddles and two identical outer paddles while the drawings call for different LH/RH outer paddles and different LH/RH inner paddles. Very confusing, but both ways will work even though the end result will be different. There were also lots of trimming to be done on the already machined mating ribs to make the paddles fit.
So I started on the aileron paddle mechanism for the folding of the wings. The 4 paddle blocks shall have two bearings each. The holes for these bearings are not honed or reamed to correct size, but are approximately 4-8 hundreds of a mm too small. I should have a reamer to do this, but a reamer this size costs 150 $. The drawings say use a reamer or sand it slightly. So I sanded and sanded and sanded... which was very fiddly because the hole is only approx 17.45 mm. Eventually I got them up to 17.5 mm, the bearings I measured to 15.52 mm, so this should be a nice fit. Here I really think Sonex should have reamed this part up to correct size. The block itself is (as all machined angle components) are really first class pieces of machined aluminium, and a press fit bearing is a close tolerance fit that requires reaming. Manual sanding and measuring and trying the pieces will do, but the amount of work is at least a factor 1000 compared to reaming. I thought about simply heating the blocks to let the temperature increase the holes, but Kerry (Sonex) said that heating should absolutely NOT be done, because the bearings will not stand the heat.
For the paddle mechanism, the drawings and the machined angled paddles does not add up at all. The machined angled parts have two identical inner paddles and two identical outer paddles while the drawings call for different LH/RH outer paddles and different LH/RH inner paddles. Very confusing, but both ways will work even though the end result will be different. There were also lots of trimming to be done on the already machined mating ribs to make the paddles fit.
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