I ran into a problem while drilling the Front H.T. Frame 6B1-1  for my fuselage. Part of the problem is that I am working off of two sets of Drawings. One set is dated 12/03 and the other is an updated set dated 2/05. The new set has correct dimensions for the part in question if you are also building the updated Horizontal Stabilizer. Unfortunately I am having to use the old dimensions which call for the Front H. T. Frame to be placed a sta. 320 (the new plans place it at 340)  because I have already completed my Horizontal Stabilizer and the attachment points will need to stay where they are. But . . . there was a mistake on the old drawings! The old drawings call for the Front H.T. Frame 6B1-1  to be 214mm wide. This is clearly too narrow. 

Here you can see my problem. It's actually worse than it looks because the Bottom Longeron (not in place here) will stick out past the skin (the part the rule is laying on) a couple of millimeters . The H.T. Frame, which is about 3mm shorter than the skin, will actually need to meet against the Longeron. 

Here's another view. I used the new drawings to reverse engineer the proper dimensions for my "custom fit" part. That's what all the extra lines are about. The line labeled 2-05 is actually the line for the H.T. fame called for in the new drawings (note: this line is actually the reference for the backside of the part, whereas the distances between the parts in the plans are from the rivet lines--I allowed for this so I could line up the part to figure the proper width as measured from the thickest point). My location, will need a part 10mm smaller than the new drawings (5mm on each side) which call for a part that is 232mm wide. So 232-10=222 right! Not 214mm as called for in the old drawings. The funny thing is I was looking through some of the photos in the assembly manual and found one that shows some space in between these exact parts on the demo. Also my friend Clyde Barcus measured his supplied part and it is 214mm as well. I'm guessing that other builders have been disappointed with this loose fit. 

This should give you some idea of the amount of space involved. The fuselage side skin will need to run down the flange beginning at the top of the photo and onto the Longeron Flange (beneath the pencil) at bottom. The gap between the two flanges (where the pencil is inserted) should be closed so the skin will be somewhat flush. This space is about 4mm wide on both sides. That would produce a very visible wave in the skin at this point. I think I'll go ahead and make a new set of forming blocks and fix this problem by making a new part of the correct dimensions. What was that again . . .lets see . . . carry the one . . .Ah, yes . . . 222mm. To be honest, if it where only about 2mm I would probably let it slide. 

Update:

Here you can see my new 222mm wide HT Frame. It comes all the way to the edge! Beautiful! Compare this photo to the first two on this page.

From this angle, with the bottom Longeron installed, you can see it's a nice fit compared to the photo above (the one with the pencil) demonstrating the large gap between these parts. The skin should lay across this nicely.

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