Upper Cowl Hinge Dimensions

[ravenstar]

I need some advice on cutting the F-01201J-1 upper cowl hinge described in section 29 figure 1. I can't make sense out of the dimensions vs. the shape of the hinge. The diagram shows a length of hinge that starts and ends with a knuckle on the top half of the hinge, but there's no way to cut a 25 7/8" segment so that it has a complete knuckle on both the start and end. The knuckles are 1/2" long spaced 1" apart. Either I have to start the cut in the middle of a knuckle and end in the middle, or I start at the end of one knuckle and end with a gap. A 25 1/2" segment would fit the diagram. What have others done with this piece?

 

[Fisherpd]

I don't think it matters much, as long as the end knuckles are "substantial" (you don't want a 1/8 inch knuckle at the end) and the fore and aft halves mate with flush ends. They should look like you cut the hinge with one cut with the hinge pin installed. Remove the hinge pin however - it is cut separately to be longer than the hinge itself.

My A/C is in the hanger so I can't look to see what I did, but I suspect one end has a knuckle that is 3/8 inch long the other is the full 1/2 inch.

 

[ravenstar]

My A/C is in the hanger so I can't look to see what I did, but I suspect one end has a knuckle that is 3/8 inch long the other is the full 1/2 inch.

Thanks, this is helpful. What concerns me is that both the diagrams show the start and end knuckles on one side of the hinge, but that's simply not possible with the given dimension unless both the start and end are partial knuckles (3/16" if both are even). That just doesn't make sense to me. I'm inclined to start with a full knuckle on one half and end with a 3/8" knuckle (instead of 1/2") on the matching half. I'm probably overthinking this way too much.

 

[Fisherpd]

Given that Vans used one figure for 2 parts of differing length, one might expect that the details would not be accurate for both parts. One would also hope that if the details were important, they would have provided 2 different drawings. Its good to ask the question, I believe that for some of the hinges it does matter, but not this case.

 

[ravenstar]

Given that Vans used one figure for 2 parts of differing length, one might expect that the details would not be accurate for both parts. One would also hope that if the details were important, they would have provided 2 different drawings. Its good to ask the question, I believe that for some of the hinges it does matter, but not this case.

Thanks! This is very helpful. I think I lost my perspective on the plans, so I've gone ahead and cut the hinges to the prescribed lengths and installed them. They seem to fit nicely so far.