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SquishyOleo

Member
Hi All!

I'm current building a 9A and have a question about substituting rivets. In a couple of spots where I just can't get an AN426AD3-3.5 to set properly, Van's told me that I could use a MK-319-BS blind rivet instead. Upon further research, I discovered that the MK blind rivets have 120 degree heads as opposed to the AN solids which have 100 degree heads. I realize that the blind rivets will probably just reform the dimple when they get set but is it standard/good practice to use a different head angle?

Thanks!
 
If the designer of your aircraft said it was ok, it ought to be ok. I have used a few of those rivets where I just couldn't get a solid rivet to work, or where, dumb me, I simply forgot to install a rivet before closing up the surface. You will use a lot more of these rivits on the bottom flap skins.
 
I used MK-319-BS rivets on the forwardmost holes on the leading edge of the HS on my -10, and they look great. When the hole is filled before painting, I don't think it'll be noticeable.
 
I have to believe when Van's okay's you to do a rivet substitution, it assumes you will prepare the holes accordingly.

For maximum quality, use either a 120 degree countersink or dimple set when installing 120 degree rivets. The end result will just look better too.
 
Same dimples - per manual...

Rick6a said:
I have to believe when Van's okay's you to do a rivet substitution, it assumes you will prepare the holes accordingly.

For maximum quality, use either a 120 degree countersink or dimple set when installing 120 degree rivets. The end result will just look better too.
Click to expand...

Rick... that would give the smoothest results....

However, Van thinks that the usual dimple is OK...

My early RV-6 construction manual (can't find a date on it...) says...

"The MK-319-BS rivet (available as optional equipment from Vans Aircraft) can be used with the same rivet spacing called for the AN rivets. The dimple countersink for the AN rivet can be used, but the holes will need to be enlarged for 3/32" to 7/32".

NOTE - 7/32 is an ERROR - I copied the error directly from the manual -- ACTUAL is 7/64

This is for the horizontal tail skin... and is repeated in the final wing skin attach instructions.

Wing bit says...

"...the MK-319-BS rivets can be used with skins prepared for AN rivets...."

Van says using the existing dimples is OK....

gil A - actually read the manual....:D
 
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Hey All,

Thanks for all your responses. I asked Van's about it and they didn't say anything about re-dimpling the hole for the 120 degree head - but I would like to do it. I'm currently looking around at the standard aircraft tool suppliers for the dies but no one seems to have them for 3/32 size. Any ideas as to where I could get my hands on a set?
 
SquishyOleo said:
Hey All,

Thanks for all your responses. I asked Van's about it and they didn't say anything about re-dimpling the hole for the 120 degree head - but I would like to do it. I'm currently looking around at the standard aircraft tool suppliers for the dies but no one seems to have them for 3/32 size. Any ideas as to where I could get my hands on a set?
Click to expand...
If you were setting CS4-4 rivets, here's what Van's says in Section 9 page 9-4 of the RV-8 builders manual. "The rivets have 120 degree countersink heads. So if you have a rare and expensive 120 degree countersink cutter this is the place to use it....." Well, the cutter is neither rare nor expensive and can be had at Cleaveland. http://www.cleavelandtoolstore.com/prodinfo.asp?number=CC120

The only dimple die I know of for 3/32" 120 degree rivets is available here.
http://www.sonexaircraft.com/eshop/cart.php?target=product&product_id=16442&category_id=260
 
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az_gila said:
"The MK-319-BS rivet (available as optional equipment from Vans Aircraft) can be used with the same rivet spacing called for the AN rivets. The dimple countersink for the AN rivet can be used, but the holes will need to be enlarged for 3/32" to 7/32".
Click to expand...

Hold your horses before drilling. 7/32" doesn't sound very good... I would rather consider 7/64" instead for those rivets.

Some info of MK-319-BS rivets:
http://rapidrivet.thomasnet.com/ite...pop-rivets/open-end-rivets/mk-319-bs?&seo=110
 
YES - 7/64 - manual error

Pirkka said:
Hold your horses before drilling. 7/32" doesn't sound very good... I would rather consider 7/64" instead for those rivets.

Some info of MK-319-BS rivets:
http://rapidrivet.thomasnet.com/ite...pop-rivets/open-end-rivets/mk-319-bs?&seo=110
Click to expand...


Pirkka - you are correct, I just transcribed the sentence from my old manual - error and all....:eek:
Van has probably fixed his error by now...:)

The number is 7/64 and I corrected the original post...
Thanks for the fact checking...

gil A
 
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