Rivet callout for sheer bars (F-704 bulkhead)

cjensen · Post by **cjensen** » Tue Feb 13, 2007 2:25 pm

CJ and I have been discussing this over the phone, and he has called Van's to ask them about it, but here's a tip for you all who haven't reached this point. The rivet callout of 426AD4-14 is simply too short for a proper shop head here. The holes drilled thru the sheer bars are not pre-drilled, and are the responsibility of the builder to locate and drill. Mine MIGHT have been wallered (is that how you spell that???) out A LITTLE, I don't know. BUT, even if they aren't, they will be too short. My shop heads, well there was NO SHOP head formed, and the rivet simply squashed in to the bar. I don't have a pic of how that looked, but CJ did get a little shop head to form on his. We happened to be working on these the same night last week. Van's told CJ that it really doesn't matter what the heads look like, or if there is little shop head there. They could be put on with glue, they told him. This is getting a little long winded, so to make this long story short, I ordered some 426AD4-16 rivets that worked perfect. I did grind one to a -15, and still found it too short. The -16 worked for me, and I have PLENTY of them left over. If anyone needs 4 or 5 of these to rivet your sheer bars, let me know, and I'll send them to you. CJ and the east coast guys, I already have you covered. When I get back from my trip this week, I'll send 'me out to ya! BTW, here's what I'm talking about...

Here's the shop head. Still a little small for an AD4, but acceptable.

Hope this helps someone. It had me frustrated for a couple of nights.

captain_john · Post by **captain_john** » Tue Feb 13, 2007 5:51 pm

Yup, That is the scoop!

I suspect that a wobbly drill bit could make the hole too wide and soak up much of the rivet length.

Drill them with an undersized bit first, then open them up to #30, guys!

CJ

RVNewsletter · Post by **RVNewsletter** » Wed Feb 14, 2007 9:19 am

When you mate your wings you'll see how the size of the rivet here doesn't matter. As long as the bar is held in place until the wing spar is inserted, which is the only goal of the rivet here.

cjensen · Post by **cjensen** » Wed Feb 14, 2007 10:47 am

Yup, that's what I gathered from conversation. My problem was that there was absolutely zero shop head on two of the four (one on each) rivets needed. I couldn't live with that, even though the rivets don't do anything but hold that bar in place. Just me.

dons · Post by **dons** » Wed Feb 14, 2007 4:49 pm

Great info, hopefully it will do me some good (in maybe 2009 if I'm lucky), thanks. That's one great thing about posts like this, there is no time limit, they can be useful years from now.

Wicked Stick · Post by **Wicked Stick** » Wed Feb 14, 2007 9:59 pm

Those rivets on my 8 were slightly the same way, although not as bad as CJ's or Chads... I think mine ended up between the gauge, but still had plenty of material to hold the block in place.

The further along I get in this kit, the more I would recommend getting a set of reamers for the common sizes, 30, 40, etc. Also get a couple of regular drill bits slightly undersize 31, 41, etc. and then ream them to final size... The holes really end up much better that way for deep parts like these, the gear legs, and the wing spar attached pieces.

TomNativeNewYorker · Post by **TomNativeNewYorker** » Thu Feb 15, 2007 4:36 am

Since I work on military aircraft that are commercially built, when solid rivets are called out on a manufacturer's drawing or in our maintenance pubs, the grip length is denoted as an asterick 999 out of 1000 times. Example: MS20426AD4-*

From my experiences, if the rivet does not look long enough before bucking, get a longer one.

Wicked Stick · Post by **Wicked Stick** » Fri Feb 16, 2007 12:06 am

I think in this case, the rivet probably looked long enough when inserted, but because of the length, if the hole is slightly larger than normaly, then alot of the length gets used up trying to expand first, so it might be hard to tell on very long rivets if the length is good before bucked if your hole is a little on the larger side.

Even still, for this application, all the rivet has to do is hold the spacer block in place until the wings are slid in and it's bolted up, so I don't see any really big deal if the shop head is undersized.

Chad, the picture of yours pretty much looks like mine and so I think that one is fine. CJ's seem a little smaller, but they are holding it in place.
I did point out though that one of his on the flush side wasn't sitting flush and that he should either shave it or re-do it so as not to scratch or marr the wing spars when inserting them later.

cjensen · Post by **cjensen** » Fri Feb 16, 2007 10:58 am

Yeah, the one in the pic is a -16. I got my order from ACS yesterday, so I'm sending the 16's on to CJ for you guys on the east side to use.

pgroell · Post by **pgroell** » Fri Feb 16, 2007 1:51 pm

I'm just finishing my today's work session, and I stumbled on this problem.
I tried to buck the small length I had avalaible, thinking that the rivet is only here to keep the part from moving around before the spar gets bolted on but with no luck.
I'll add some longer rivets to my next order as I'm on the east side but of the Atlantic.
Pascal

cjensen · Post by **cjensen** » Fri Feb 16, 2007 2:46 pm

You only need a few, and they're cheap. I ordered a tenth of a pound from ACS&S for $1.86.

That'll get you plenty, and spares to share!

RVNewsletter · Post by **RVNewsletter** » Sat Feb 17, 2007 9:48 am

cjensen wrote:Yup, that's what I gathered from conversation. My problem was that there was absolutely zero shop head on two of the four (one on each) rivets needed. I couldn't live with that, even though the rivets don't do anything but hold that bar in place. Just me.

That was my situation too. Sent pix to Van's at the time and they enlightened me a bit on what those bars were doing.

captain_john · Post by **captain_john** » Wed Feb 21, 2007 8:58 pm

HOLY GUACAMOLE!

Those -16's take a WICKED BEATIN' to set!

I whacked the CRAP outta them, but they look nice now!

Thanks Chad! They were just the ticket!

Thermos et al... lemme know when you need these!

They are just what the doctor ordered!

CJ

cjensen · Post by **cjensen** » Wed Feb 21, 2007 11:28 pm

No problem at'ol! Glad they worked for ya!

Thermos · Post by **Thermos** » Tue Dec 22, 2009 5:29 pm

captain_john wrote:Thermos et al... lemme know when you need these!

Well, only two and a half years later...I'm ready!

Maybe it's time for a trip down to the Cape? I've also got some stuff to return to WS.

Wicked Stick · Post by **Wicked Stick** » Tue Dec 22, 2009 9:28 pm

Thermos wrote:
captain_john wrote:Thermos et al... lemme know when you need these!
Well, only two and a half years later...I'm ready!

Maybe it's time for a trip down to the Cape? I've also got some stuff to return to WS.

Lemme know when you want to drop by.. (This coming weekend is fine with me.) whatcha got of mine ? guess it's been so long I've forgotten

captain_john · Post by **captain_john** » Tue Dec 22, 2009 9:57 pm

2.5 years? Closer to 3!!!

Thermos, I was reminiscing about this thread today too when you texted me!

I need to look around and make sure they are still on hand. I am sure they are right where I left them... in the rivet bins!

Sunday I will be around. If you want to come by and see the systems going in, lemme know!

CJ

Thermos · Post by **Thermos** » Wed Dec 23, 2009 3:13 pm

captain_john wrote:2.5 years? Closer to 3!!!

Hey...let me enjoy my little fantasies, ok?

Dave, I've got your aileron/flap V-jigs and your pipe drilling jig too.

Sunday could be good...gotta check with the home front as we're supposed to be returning from New Hampshire that day.

RivetBangers.com

Rivet callout for sheer bars (F-704 bulkhead)

Rivet callout for sheer bars (F-704 bulkhead)

Well this is a timely thread