flickroll

flickroll

Well Known Member
I have started construction of an RV8 empennage kit. I have a dumb question regarding orientation of the rivets on the horizontal and vertical stab spars. Which way do the shop heads go, forward, aft, or does it matter? I've looked everywhere and cannot find reference to this. Thanks
 
No Dumb Question

There's no such thing as dumb question, only dumb building by continuing on without knowing what to do. :D

This has been discussed quite a bit on here but it's probably one of those things that's hard to find with the search engine.

The general rule of thumb is to orient the rivets so the shop head is on the thicker material. If you put the shop head on the thinner material it may distort the material which is why you put it on the thicker side.
 
I agree with Jamie's comments, however, also understand that it isn't a hard and fast rule. If you're able to set a much better rivet in one direction or the other, do whatever works best for the given situation. If you end up folding the rivet over just to get it oriented on the "right" side...
 
agreed with both of the above comments... Sometimes, when I'm confused as to what side to put the shop head on with two peices of equal thickness, I just look at Brad's site and copy what he did! :D He's building a -7, but still a great site. (http://www.rv7factory.com)
 
One more thing to consider...repairs. Not that I *ever* want to drill out a mess o' rivets to replace a part or effect a repair, when faced with a choice (like thicknesses of metal, etc.), we try to opt for having the factory head on the most accessible side, figuring if there is *ever* a need for repair, it'll be way easier to drill out the rivet.

Of course, this is probably waaaay overkill and thinking too much about it...
 
Jamie said:
The general rule of thumb is to orient the rivets so the shop head is on the thicker material. If you put the shop head on the thinner material it may distort the material which is why you put it on the thicker side.
Click to expand...

Van's has not specified direction in any way so don't see why not follow this. It will be strong enough build either way.

http://home.earthlink.net/~gilalex/rivet_spec/rivet_a.htm


MILITARY SPECIFICATION (MIL-R-47196A) - RIVETS, BUCK TYPE, PREPARATION FOR AND INSTALLATION OF

"3.3 Installation.
3.3.3.1 Head direction. Unless specified on the engineering drawing or specification, the manufactured head of the rivet shall be located on exterior surfaces."
 
Rivets on HS rear spar

FWIW, I thought about rivet replacement at some point in the future and that it is recomended that factory heads go forward. However, when actual rivet setting time presented itself, I did shop heads aft because - It was much easier to set with a squeezer and a better job done. The sqweezer yoke was a little too deep to clear the spar flange. So there you are! Ya I did figure out that I could have reversed the sets but it's done.
 
Rivets on HS rear spar

FWIW, I thought about rivet replacement at some point in the future and that it is recomended that factory heads go forward. However, when actual rivet setting time presented itself, I did shop heads aft because - It was much easier to set with a squeezer and a better job done. The squeezer yoke was a little too deep to clear the spar flange. So there you are! Ya I did figure out that I could have reversed the sets but it's done.
 
flickroll said:
I have started construction of an RV8 empennage kit. I have a dumb question regarding orientation of the rivets on the horizontal and vertical stab spars. Which way do the shop heads go, forward, aft, or does it matter? I've looked everywhere and cannot find reference to this. Thanks
Click to expand...

I did it both ways (built two HS's - don't ask). I did my second HS with the manufactured heads facing out because on the first one the shop heads kept interfering with squeezing the skin rivets. My pneumatic squeezer actually nibbled the shop heads on a couple of them. Besides, I think it looks much better with the man'ned heads facing out. Feel free to follow my follies here: http://www.rv8alog.com/empennage/empennage.htm
 
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Jorge, Nice log site

I just finished looking through your builders site. NICE JOB! Great site. I'm sure I'll be referring to it frequently.
 
Interesting reading. Here's a couple of things that I did not know:

3.3.3.2 Rivet set. Flat dies may be used on the manufactured head of universal head rivets provided the head is not flattened beyond the dimensions specified on Table II

*** This means that you can squeeze universal head rivets with a flat die. Not sure why you would want to, but there may be situations where its useful.

3.3.3.4.1 Driven universal heads. Driven universal heads may be formed on the shank side of the rivet using the next smaller size universal type head riveting die (example, 1/8 inch die for 5/32 inch shop head rivet). Driven universal type head sizes shall conform to the respective rivet diameter shown on Table III, unless otherwise specified on the engineering drawing or specification.

*** I remember asking my inspector about this.... could I use a universal set to backrivet? Looks like it's OK!

Vern
 
vlittle said:
3.3.3.2 Rivet set. Flat dies may be used on the manufactured head of universal head rivets provided the head is not flattened beyond the dimensions specified on Table II

*** This means that you can squeeze universal head rivets with a flat die. Not sure why you would want to, but there may be situations where its useful.
Click to expand...

Do you remember that tanks has some tooling holes in the most outer ribs? Van's one tip was to fill it with rivet. You don't need that big rivets anywhere else so you don't have suitable universal head for riveter either but you could use flat head here to do the job.
 
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