[dbaflyer]

I cleco'd on the top skin tonight and it fits well with the exception of all 16 of the forward bottom rivets. This is on both sides. The holes seem to be off a couple 32nds and I was not able to get the clecos in. I started at the aft end and worked forward but after staring at 8 clecos laying sideways I decide it just wasn't going to pull together like so many other parts do. Has this been an issue for any one else and do you have any thoughts on how to move the alignment a little bit?

The longeron and side skin are already counter sunk and dimpled from the QB factory. If I just drill these holes with the skin off and dimple do you think they'd be easier to pull into alignment?

 

[airguy]

It appears that the longeron holes in the skin are slightly low - can you work the flange on the bulkhead to give a slight bit of uplift on the entire skin to bring those into alignment? Could the bulkhead be low by that amount, resulting in the misalignment by pulling the skin down? It might be easier to drill out the bulkhead and refit it in alignment with the skin.

 

[RV9Ralph]

Did you remove the protective plastic film on the underside of the ront panel? It makes a difference in fit on other locations during the build.

RV9Ralph

 

[MarkW]

Dennis,
You did not mention if the skin rivet holes are forward, aft, low or high.
First do not drill off the fuse and expect them to line up later. I just finished this skin a few weeks ago and had no problems. I found that any time something did not line up correctly, it was something I was doing wrong. Is it possible that this skin will only go on one way. Is there a topside and bottom side? Is it on upside down? It appears your problem is starting at the lower skin seam going forward. If your alignment problem is fore and aft, there may be a problem. Let me know if you need me to measure anything. My unfinished plane is 20' away.

 

[dbaflyer]

Today I tried to just do that row of rivets to see if it would line up. This would eliminate the blue plastic and I think the bulkhead position. They just do not line up. This time I started at the fore point and worked back. Everyone of the first 16 lined up great. Then starting in the next one they are off and alignment issues start. You can see the skin to longeron here is really flush and good.

Here are the same good ones from the outside.

From the inside along the poor fit. On some the F7112 is pulled away from the lower skin. In other cases the two skins are together and pulled away from the longeron.

This is from lying on the floor and lookup up:

 

[MarkW]

I always assumed that Van's used a standard spacing between skin rivets whether they were wing, emp. or fuse. I just measured this skin and find different spacing. The forward rivet holes that you. Are having a problem with are about 31/32". The ones aft of the lower skin seam are closer to 1". For the fun of it I measured the very forward panel skin and it is more like 28/32".

 

[dbaflyer]

I just measured my skin and it matches yours. The aft holes are very close to 1 inch and the fore holes are 31/32. So are the holes already dimpled on the fuselage. There is one spot on the fuselage between holes 24 and 25 counting from aft that measure 1 and 1/32. Possibly just slightly more. But the skin measures 1 inch. Not sure how to deal with that. This is right were the two side skins overlap and just aft of the F706A bulkhead. I'll call Vans Monday and see what they say.

 

[dbaflyer]

Vans got back to me on options for resolving the hole misalignment. Option 1 is to use my existing skin and drill the 16 forward holes to #30, dimple the F7112 #30, and then countersink the side skin and longeron to receive the #30 dimpled skin. Option 2 is to have a special F7112 made without the forward 16 holes prepunched. I would then attach that skin to the side of the fuselage with the after 16 holes clecod in place. Then back drill from inside the fuselage through the existings holes I have to create brand new holes in the F7112.

I am leaning toward option #2 because if I mess that up only the skin is damaged not the fuselage structure. In addition Drilling the current skin #30 and getting that hole to line up with the fuselage won't be easy since I have to offset the hole so the center of the #30 hole lines up 1/32nd inch over. I'm not as worried about have 16 rivets on either side of the fuselage that are 1/8 inch rivets, but it would look a bit odd.

Other pros/cons of these two options?

 

[a8301]

Top skin on my 9A was 1/2 hole out of alinement (QB) I found a minor mistake the factory made. Drilled out some rivets fixed it and it pulled every thing in place.

Bruce 9A

 

[Rupester]

I agree ....go the new skin route

... putting a new skin on there, and backdrilling the 16 bad holes makes a ton of sense. Easy to do at this point; you have little time invested in the existing F7112. Option A seems too .... well .... "klugey", if you know what I mean.

 

[grayforge]

I concur on method 2. This will match the holes exactly and look correct as well.

 

[dbaflyer]

vans sent new skin

I had it clecoed on Friday, but just got done match drilling it tonight and it looks good. I can't say enough for how easy it was to work with Sterling at Vans to get this done. Very good experience.