|July 25, 2004||HOME|
Two days ago I made the f-798 shims and drilled the forward HS spar to the rear fuselage deck. This morning I rechecked all that. I spent the extra time on it because the plans show about 20 different attachments in one view. I just wanted to be sure I hadn't missed anything. Well, I had missed something, but I'll get to that later.
I drilled the pilot holes through the f-711c HS attachment bars and the rear HS spar. The plans don't really call it out, but it is obvious that the spacing should be such that the bolts will center on the two reinforcing bars on the HS rear spar.
The item I had missed was the making and attaching of the f-712d up elevator stop. Here, I marked out the rough dimensions of the cut. Van's calls for fabricating this from a piece of 1x1/2 angle. It doesn't make sense because neither leg is longer than 1 inch, so why not use 1x1 angle? I dutifully followed their directions anyway...
The plans also call for trimming 5/8th inch off the vs-702 (the vertical stabilizer rear spar) at the bottom. I measured it and marked it and rechecked it.
Note below, the elevation transformation inducer (indicated by the yellow arrow) necessarily employed to provide the correct angle for hacksaw work. Yeah, I hate being short! At least a wine box provides the proper height adjustment.
I fitted and drilled the VS front spar attachment plate (f-781) to the front spar where it had been trimmed. Note the little jog in the attachment plate. This offsets the leading edge of the VS 1/4" to compensate for prop torque at cruise. You see some builders adding a trim plate to the rudder because they didn't get this right. I hope I don't have to do that...
Here you can see the angle set into the attachment plate. The plans also call out optional use of a spacer (f-781b) but I didn't need it. The fit was perfect.
With the HS fully attached, I clamped the VS in place and began checking alignment. I rechecked the alignment of the HS for being both perpendicular to the airframe and to have 0 degree incidence. Both were right on. You check the VS by measuring from the top to the tip of the HS and look for identical measurements in both directions. I struggled with this a little as I was using the soft padded clamps and they tend to wiggle a little. I added a regular c-clamp at the bottom and fixed that problem.
Just another shot of everything clamped together. By this point, I had drilled the f-781 attachment plate to the HS front spar. I still don't have the up elevator stop in place, so I'm a little ahead of myself here.
Oh! The cavalry has arrived! Bill popped his head into the shop to provide some unsolicited advice. Here he's suggesting that I should get the fuselage up on saw horses. "Oh honey! Your ideas are so wonderful!" Now he's happy!
Ah yes, I think he's measuring to see if the vertical stabilizer is the right thickness. "Doesn't make sense," you say? Why else would he be up there with a tape measure? He is so helpful. How could I do this without him?