rvrepairer
I'm New Here
Hi, I am building an RV4 empennage and I have a question to which the answer is probably obvious, but I want to make sure prior to drilling all that expensive aluminium.
In cross section, a flange or stiffener consists of a flat portion, then a radiused portion joining the flat portion to the web. It is my job to choose where to drill holes, both longitudinally along the length of the flange, and laterally in terms of the spacing between the web and the outside edge of the flange.
W
W
W
W
W
.C
...C
......C
...........C
...................C F F F F F F F F
Where W is web; C = curve (radius) and F = flange
The obvious place to drill a hole is half way between the web and the outside edge of the flange:
W
W
W
W
W
.C
...C
......C
...........C
...................C F H F F F F F F
But you could argue that the dimpler will mark the radius because it is too close to it, which will work harden this portion and distort the part.
Perhaps it would make more sense to drill the hole half-way along the flat portion of the flange:
W
W
W
W
W
.C
...C
......C
...........C
...................C F F F F H F F F F
Like so.
Or you could contrive arguments that it would make the most sense to drill the hole as close to the web as possible... Or as close to the edge of the flange as possible whilst respecting edge clearances...
I've looked at lots of pictures but it's not quite clear to me which strategy VANS is using.
Next question - if I have a long flange presumably it makes sense to have the first and last rivets in the flange as close as edge-clearances allow to each end of the flange?
Many thanks for putting my mind at rest as to the correct approaches.
In cross section, a flange or stiffener consists of a flat portion, then a radiused portion joining the flat portion to the web. It is my job to choose where to drill holes, both longitudinally along the length of the flange, and laterally in terms of the spacing between the web and the outside edge of the flange.
W
W
W
W
W
.C
...C
......C
...........C
...................C F F F F F F F F
Where W is web; C = curve (radius) and F = flange
The obvious place to drill a hole is half way between the web and the outside edge of the flange:
W
W
W
W
W
.C
...C
......C
...........C
...................C F H F F F F F F
But you could argue that the dimpler will mark the radius because it is too close to it, which will work harden this portion and distort the part.
Perhaps it would make more sense to drill the hole half-way along the flat portion of the flange:
W
W
W
W
W
.C
...C
......C
...........C
...................C F F F F H F F F F
Like so.
Or you could contrive arguments that it would make the most sense to drill the hole as close to the web as possible... Or as close to the edge of the flange as possible whilst respecting edge clearances...
I've looked at lots of pictures but it's not quite clear to me which strategy VANS is using.
Next question - if I have a long flange presumably it makes sense to have the first and last rivets in the flange as close as edge-clearances allow to each end of the flange?
Many thanks for putting my mind at rest as to the correct approaches.
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