VS fairing holes

Hi,

I am currently finishing the preparations on the vertical stabilizer. On the side view section on DWG 6 there are 6 fairing attachment points marked with a circle and a cross. Do I need to dimple these holes in the root rib VS-704 / nose rib VS-705 and the skinn VS-901 like the other holes? The remark says "Leave open for empennage fairing attach, 6 places on each side of the assembly". I understand that this is just that I am not suppose to rivet them, but nothing is mentioned about dimpling. On DWG 44 about the fairing attachment, there is mentioned that 8 AN507C623R8 screws are used.

Secondly, the last hole in both the VS-705 and VS-706 rib, just in the front bending of the skin VS-901, is not pre drilled in the rib. Do I suppose to drill this myself, using the prepunched hole in the skinn as a guide? Or is this done with a reason?

Thank you!

No dimple

On drawing 44, upper left corner, you'll see that in about two years you'll be installing k-1000-06 plate nuts in the crossed out holes to hold the emp fairing in place. K-1000-06 plate nuts are not countersunk and therefore you shouldn't dimple. The screw however is countersunk so hopefully there is enough meat in the fiberglass fairing to accommodate.

Thanks for your prompt response!

Great, I do not countersink the 6 holes on both sides. The plate nut K1000-06 itself probably has two holes that need to be countersunk, right? Strange that nothing is mentioned about that now, because that means that I have to dimple the skinn & rib together in one go.

Any idea on the second question about the two last holes of the rib that are not predrilled in the rib? Do I have to drill them myself in the rib?

WVM said:

Thanks for your prompt response!

Great, I do not countersink the 6 holes on both sides. The plate nut K1000-06 itself probably has two holes that need to be countersunk, right? Strange that nothing is mentioned about that now, because that means that I have to dimple the skinn & rib together in one go.

Any idea on the second question about the two last holes of the rib that are not predrilled in the rib? Do I have to drill them myself in the rib?

Click to expand...

It's one of those little puzzles that Vans built into the project so that you have to think now and then. Match drill the ribs.

Thanks! Expensive puzzle...

So.... If you have dimpled already? Not having seen the proper nut plate until the wings arrived, and not finding a "k1000" in my reference books, I took my cue off the nature of the screw.

I read about the negatives of flatten a dimple just the other day that so not does not seem to be an option.

I understand these holes will be enlarged to #27 which will reduce the dimple a bit, so is it acceptable to put the counter-sink required into the main hole of the nut plate enough to get it to lay flush? Or use the k1100-6 instead (will the screw be long enough)?

Hi RPCoates,

I luckely didn't dimple yet! But a friend who is completing a RV7 is currently attaching the fairings and did not dimple them. He wasn't sure that this needed to be done upfront at the construction of the stabilisor. As I now have the option to do so, he informed me about it. He was happy to not have dimpled the holes upfront, but noticed that the nutplates also need two dimples, and nothing is mentioned in the empennage kit to drill and dimple those two holes per nutplate.

I marked the skin and ribs to not dimple the holes.

Thanks

Another wrinkle in the puzzle is how you plan to attach the empennage fairing. I ended up just putting in a nutplate in the aft most VS hole. Same story on the HS. I think the plans are overkill on the number of screws holding down the fairing.



You can see the blue dots where the holes were left open. After I got the fairing fitting really tight on the VS/HS skins, I ended up dimpleing and filling those holes with rivets.

WVM said:

Thanks for your prompt response!

Great, I do not countersink the 6 holes on both sides. The plate nut K1000-06 itself probably has two holes that need to be countersunk, right? Strange that nothing is mentioned about that now, because that means that I have to dimple the skinn & rib together in one go. ...

Click to expand...

Get some reduced head rivets for attaching nut plates. You can machine countersink for them with just a few turns of a speed deburring tool.