S

Skyhawk

Member
Hi.

I riveted the rear HS spar, HS603 to HS609, yeasterday. Went out pretty nice. But, as allways, later I began wondering if the way the rivet is has any impoprtence? I have the shop head backwards, on the spardoublers, but when I look around everybody else seems to have it the other way.
Does it matter, for example in this case with two pieces of different chicknes, and one of them is more like to have elonginated holes? If its fills better on the shop head, i dont now.

Your teories please?. :) If any, maybe i?m just to pedantic...
 
Personally I try to put the shop head on the side with the thicker material. I think this method is slightly stronger. I have no evidence to back this up. As far as I know 43-13 does not mention this anywhere. It's your choice.
 
Skyhawk said:
Hi.

I riveted the rear HS spar, HS603 to HS609, yeasterday. Went out pretty nice. But, as allways, later I began wondering if the way the rivet is has any impoprtence? I have the shop head backwards, on the spardoublers, but when I look around everybody else seems to have it the other way.
Does it matter, for example in this case with two pieces of different chicknes, and one of them is more like to have elonginated holes? If its fills better on the shop head, i dont now.

Your teories please?. :) If any, maybe i?m just to pedantic...
Click to expand...

Most recommend putting the manufactured head on the thinnest material side. This is to prevent distortion of the thinner material (which it does nicely). Sometimes it just looks better to do it opposite to this so sometimes people ignore this rule.
 
Skyhawk,

Terminology:

- FACTORY HEAD (or MANUFACTURED HEAD): the head that was already formed when you received the rivet. AN470s have round/dome factory heads. AN427s have 100-degree c-sunk flush factory heads.

- SHOP HEAD: the head that you form in the shop by squeezing/bucking.

If you put the shop head of those rivets on the 1/8" doubler side, then you did the right thing.

In this case, factory heads on the front of the spar, shop heads on the doubler at the rear.

When you rivet HS-810 and HS-814 angles to the front spar, you'll put the shop heads on the 810/814 side...thicker material.

This isn't a hard & fast rule, just a rule of thumb. Use it when you can, but on occasion it makes sense to deviate. You'll see as you go along...
 
Mel, me and countless others follow the accepted practice of GENERALLY placing the manufactured head against the thinnest material in a stackup. This is not a rule chiseled in stone but practically speaking, doing so lessens the chance of the material distorting around the rivet head. At times however, I will orient the manufactured head on a given line of rivets to simply produce a more pleasing look. Structurally, it makes no difference and unless a specific orientation is noted by the designer, the choice is yours.
 
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Rick6a said:
Mel, me and countless others follow the accepted practice of GENERALLY placing the manufactured head against the thickest material in a stackup.
Click to expand...
Terminology check...

SHOP HEAD = the bucktail. And Mel just said the *opposite* below. Let's be careful what we say. Newbies are reading this!
 
dan said:
Terminology check...

SHOP HEAD = the bucktail. And Mel just said the *opposite* below. Let's be careful what we say. Newbies are reading this!
Click to expand...
Sorry for the misinformation. I stand corrected. The MANUFACTURED head is generally placed against the thinnest material in a given stackup. I should proof read a bit more carefully!
 
I agree with all of the above except nobody has mentioned that you should also consider that, in the event you need to drill the rivet out, from which side will you have best access to the factory head. You can drill out rivets from the shop head side, but it's not fun.
 
Skyhawk said:
Hi.

I riveted the rear HS spar, HS603 to HS609, yeasterday. Went out pretty nice. But, as allways, later I began wondering if the way the rivet is has any impoprtence? I have the shop head backwards, on the spardoublers, but when I look around everybody else seems to have it the other way.
Does it matter, for example in this case with two pieces of different chicknes, and one of them is more like to have elonginated holes? If its fills better on the shop head, i dont now.

Your teories please?. :) If any, maybe i?m just to pedantic...
Click to expand...
I did it both ways (on separate spars, I mangled my first HS).

What you did is right, but ... (there's always a but) ... be carefull when you go to rivet your skins because the shop heads (the ones you made) will stick out slightly higher than the manufactured head (the one the rivet came with).

When you go to squeeze the rear of the skins, some of the spar rivets will interfere with some of the skin rivets. If you're careless you may chip off a chunk of shop head and you won't be able to replace that rivet without taking off the skin.
 
Called Vans myself on that one

I was told by Vans that once driven, the material does not care what side the shop head is on so strength is not an issue. As far as what looks better or more technically correct? I'm not the one to say.
 
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