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-   -   Flap/rivet? (https://vansairforce.net/community/showthread.php?t=112512)

s10sakota 04-30-2014 06:04 AM

Flap/rivet?
 
Sorry I don't have the part number handy, but if you built your flaps you will recognize this rib and reinforcement plate!



The big hole is where the flap actuator attaches to a nutplate riveted to both the rib and bracket.

As you can see, one hole is countersunk in the bracket, but what about the other hole? (there's a cleco in the hole in the pic). This rib is way too thin to countersink...right?

What am I to do here? :confused:

Thanks!

derLuigi 04-30-2014 06:31 AM

I used a NAS1097AD3 rivet here, that's a flush head AD3 rivet with a smaller head. You can get them from Van's, they're in "The List".

I read you could simply dimple the rib and dimple the lug of the nutplate as well, I've only tried that once though (wasn't impressed with the end result) and now use the NAS1097 most of the time.

s10sakota 04-30-2014 06:36 AM

Ok thanks Mario-I just ordered some from Vans!

More than likely I'll need some 'oops' rivets during the rest of the build anyway LOL.

aeroaddict 04-30-2014 07:23 AM

What Mario said. I used my 6 fluted deburring tool to make a small countersink in the rib. I was careful on the countersink not to create a sharp edge in the hole. The rivet was not perfectly flush but has worked just fine.

longranger 04-30-2014 08:13 AM

I install almost all of my nutplates with reduced head rivets. About 10 turns or so with a deburring tool makes a good countersink.

compren 04-30-2014 09:38 AM

I did this last night
 
I dimpled the rib and countersunk the nut plate. Worked fine. I really don't see why you couldn't just use a AN470 here, but I'm also not done with my plane and don't know if anything sits flush to that location, so I chose to just follow the plans...

bill v 04-30-2014 10:10 AM

an470
 
bought some long an470's and cut them to lenght when i find this type of situation. most times a 426 works but requires the work of countersinking. the opps #3 are more important as they have more uses i used a lot of them for nutplates and filling unused holes (ex. hole for steps if not using steps)

s10sakota 04-30-2014 10:25 AM

I did order the opps rivets (NAS1097).

I always thought that oops rivets had the same manuf. head but just had a slightly larger diameter shank?

Is there something different about the head that doesn't require as deep of a countersink?

s10sakota 04-30-2014 10:28 AM

I like the idea of using an AN470 round head rivet better I think and I can't any issues with interference.

I think I will order some of these rivets and not worry about the countersinking on the thin rib.

longranger 04-30-2014 10:58 AM

Quote:

Originally Posted by s10sakota (Post 875701)
I did order the opps rivets (NAS1097).

I always thought that oops rivets had the same manuf. head but just had a slightly larger diameter shank?

Is there something different about the head that doesn't require as deep of a countersink?

Actually the NAS rivets are "reduced head" rivets. The shanks are the same size for the same dash number, and the head is for a rivet with the next lower dash number. What happens is, if you enlarge a #3 hole, you go to a -4 rivet with a -3 head. With the nutplates, I use -3 rivets with a -2 head - very small, very shallow countersink required.


Quote:

Originally Posted by s10sakota (Post 875706)
I like the idea of using an AN470 round head rivet better I think and I can't any issues with interference.

I think I will order some of these rivets and not worry about the countersinking on the thin rib.

Not a bad solution, just make sure there aren't going to be any issues with overlapping parts; it happens sometimes (inspection covers and cockpit floors come to mind). Nutplate attach rivets see no tensile loads, so the shallow countersink for a -2 head is no problem.

OLDSAM 04-30-2014 11:52 AM

Use the 470
 
I had earlier had a chance to pick up some AN470 AD3 rivets in a few different lengths, this was a perfect spot for a couple of them, one each flap. Don't remember if I cut off the -4's or not. Works beautifully, looks great, the head is still well below the surface of the doubler, no material removed from the rib, all good.

Thermos 04-30-2014 12:37 PM

Quote:

Originally Posted by bill v (Post 875694)
bought some long an470's and cut them to length

+1, I have a small stock of AN470AD3s for just this situation.

grayforge 04-30-2014 06:17 PM

For 0.032 or thicker sheet, I use NAS1097's to rivet nutplates on. For anything thinner, I just dimple the sheet metal as well as the nutplates, even going so far as to use Cleaveland Tools' SubStructure dies on the nutplates.

I recall reading that dimpling is more secure than machine countersinking since the metal parts can't slide in relation to each other as well.

wjb 04-30-2014 10:53 PM

I dimpled this hole and drove in a flush head rivet per the plans. Everything lines up nicely.


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