Rivet line alignment

[fairchild]

Thinking about the rivet line in the wing skins. As you look down the wing it would be nice to have rivets into the ribs be straight lines. To get that I have to have the
fluits in the ribs be straight as well. The rivet positions are marked on the master rib form (from the rib page in plans) by tick marks a 1.5 inch intervals down the rib flanges.
If I cut all my nose rib blanks the same length--- (with the idea of trimming later depending on their position) - they will be fluited before I trim so that will cause the rivet line
to be staggered. I can deal with that--- but i dont want the trimming to throw off the rivet spacing- OR--- get me in a situation where a rivet is trying to go in on the edge of the fluit because I
trimmed a bunch off the back of the rib and the whole rib shifted to the rear (nose rib-)

Is there an easy solution to this - besides just calculating the nearly exact (less a little fudge factor) length of each nose rib based on what the spar is doing--- I believe
John snapp did this somehow correctly as he mentions having two 1/8 inch spacers that screw to the back of his cutting jig so he can modulate between 3 different lengths--
(thats what I get from his video---- if I understand what im seeing)

I feel like I might be able to do that If ( I say IF....) I can figure out what the spar heights are at the rib stations. That seems like it is hard to see on the plans. The spar drawing
does not appear particularly transparent to my eye there-- I cant really tell if there are 3 lengths or 4 lengths of ribs- (model B plans)

Anyone here cut them using shims on the cutting form (using the router like JS did) ?

Id rather go slow and NOT make any big mistakes......

Tim

[marcusofcotton]

Rivet lines should not be affected by your Spar cap strip trimming.
Study your plans a bit more and then draw out where your cap strips will be. Should be plenty of information to do that and then you will know.

[S Lathrop]

I made certain that all the flutes on the rib flanges were in the same place. over the entire length of the ribs I marked the rib forming block where the flutes were to be placed. Getting the rivet lines straight on the wing skins was easy. I had to do this because of the way I formed flanges for the holes in the ribs. I made a block similar to the rib forming block but with all the flute positions cut into the block. and the block was slightly smaller to allow for the radius of the flanges.

I think this is what you were asking?

[Chris In Milwaukee]

I agree with all of the above. The rivet location is in the same place on each rib, regardless of where you trim the spar side. No worries there.

Check my build thread here to see what we're talking about:

https://bearhawkforums.com/forum/bearhawk-patrol-plans-build/21676-fluting-party

Those flutes will always be in the same spot.

[fairchild]

Are yall saying that the nose rib (for instance ) does NOT move closer to the spar if you trim the tail off the nose rib ???? (you are in effect)
OH WAIT------- if I measured my rivet tick marks from the FRONT of the nose rib---- then where ever I trimmed the tail of the rib on the spar side---
it would HAVE to be the same as all of the others. I just DONT want to lay out my 1+1/2 inch spacing by starting at the aft end of the untrimmed tail end.
OR--- I could just lay the finished rib on the Master form to mark it - as long as the FRONT profile is matched up--- and just ignore that overlength tail end.
yes- I see now-------- couldnt see the forest for the trees ! I had it in my head that I would be marking the rivet positions from the back (which is variable)


Also--- Got Eric newton's Wing CD today in the mail. YEAHHHHHH !!!!! will dive into that tomorrow head first !

Thanks for the re-cageing my brains gyro !
Tim