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Bill Cannon

Member
I should have read the thread on wrong size rivets first but I didn't. I did read in Van's section 5 that sometimes a shorter rivet is called for but will do the job adequately. From now on I will cut a longer rivet but I have driven the called out for rivets and they are just a little shy on the .5/1.5 requirements. The mil specs for solid driven rivets (that I downloaded I think from here but maybe somewhere else) have slightly looser tolerances and the shop head meets those when measured with a micrometer.

The obvious question is.....

Do I drill them out and put in cut ones or let it be? Like I said from now on I will cut longer ones.

When Van's says that they will be adequate does he mean they should still meet the .5/1.5 requirement if set correctly or are they saying that the shop head will be a little small but that it's OK?????


This is my first post of many I am sure. I just started my 10. The rivets in question are on the Vert stab, rear spar attaching the lower rudder brackets.

Thanks in advance,

Bill
 
Hi Bill,
Ever hear the expression: "Let sleeping dogs lie"? The almost universal opinion here is to leave good rivets alone. You will do more damage by trying to drill them out. A few that don't exactly meet specs won't even be a thought in the whole picture. Trust the folks who have already gone before you, and Vans, who knows a thing or two about building airplanes. Build on!
 
After a while you should get a feel for good rivets. Ugly rivets that are a bear to drill out were probably OK to start with. Truly bad rivets are easy to remove - they seem to fall out when you drill them. You'll also start checking out rivets at air museums - Smithsonian, USAF Dayton, Duxford etc. There are some ugly rivets in some nice aeroplanes!
 
Shear Fasteners

Rivets are meant to be primarily for shear applications.

The important part is that they have expanded to fill the holes in all the material (layers) that the rivet went through, and then still had a sufficient formation of a greater sizes shop head, than the material directly under the shop head.

Unless it looks like bent nail that has a long tail and wiggles it will work.

I have found that if I am having difficulty forming a nice shop head, that slightly shorter will look better than too long when done.

Longer rivets are more difficult to replace, along with rivets in very thin skins.

If there are many rivets in the same structural piece and they are almost all looking right, it should not be as big a concern as, say, a bracket held on by two rivets and one seams crummy.

Practice ,makes closer to perfect, a perfect job seems to never get finished!:rolleyes:
 
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Specs...

Bill Cannon said:
......

When Van's says that they will be adequate does he mean they should still meet the .5/1.5 requirement if set correctly or are they saying that the shop head will be a little small but that it's OK?????
.....
Bill
Click to expand...

Bill... the 1.5/0.5 is just a center point of the acceptable range.

The Mil-Spec you referred to gives the entire range of dimensions, and any dimension within that range is a "good" rivet.

By all means, fix bad rivets, but it's not bad if it's in the range...:)
The specification is quite broad.

A copy of the spec. is on my web site.... gil A

http://home.earthlink.net/~gilalex/rivet_spec/rivet_a.htm
 
Seems like even though they were a little short they are probably the best looking ones I've set so far. I will keep them as part of the eventual finished product. I can see the tendency to drill out ones that were ok is there but going away quick. The plane I'm taking to smelly Delhi tomorrow probably has many that look worse than the one's that I have removed so far. Knowing this will help me take many more steps forward and less back.

Thanks again guys,

Bill
 
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