[AntiGravity]

I've just finished match drilling the skins to the left wing and am ready to move onwards. On page 7-4 of the destructions under "Fitting the main skins" it says "Draw a couple of lines on the main skins that intersect at the center of the hole for the tiedown eye".

Now, I may be missing something, but what for? The tie down eye is on the forward side of the spar so a hole would need to be made in the LE skin. Or is there something else I have missed in the drawings?

While I wait for some knowledgeable person to enlighten me, I shall go fit my Evans Aviation pitot tube (missed the GB on that one too ).

Thanks Guys,

 

[Kevin Horton]

Does the leading edge skin have a hole in it for the tie down? If not, after clecoing the leading edge skin in place, you would extend those two lines you made on the main skins, and mark where they cross on the leading edge skin. Make the tie down hole where those two lines cross.

 

[ptrotter]

Jeff,

I saw the same thing. I just assumed that Van's made a change sometime in the past and didn't update the instructions. As far as I can tell you can ignore it.

 

[AntiGravity]

Thanks

Thanks. I'll be drilling the LE tonight or tomorrow (may need to work late tonight ) so I'll check out the tiedown hole. Its rather exciting that I now have a wing though... kind of...

 

[treeez]

The hole in the leading edge skin may not line up exactly with the hole in the tie down. By drawing the lines, you know which way to adjust the hole location when you drill it out to size.

 

[Mustang]

Should the hole be big enough to.....

Yes, and I have seen this tie-down hole done a couple of different ways. On the RV-4 that I fly, the hole is enlarged enough to allow the forged fitting to bottom out on the aluminum extrusion. However, in the instructions, it says to only tap it to one inch. This means the forging will just barely touch the skin when tightened down as the hole in the QB skins does not swallow the base of the forging.

What is the preferred method?

1.) A big hole and the tapping deep enough for the forging to be tightened onto the extrusion. or,

2.) A small hole and the tapping extending to only one inch so that the forging base is just kissing the skin when tightened to the bottom of the tapped area of the extrusion.

For mooring in strong winds I would feel more comfortable with a deeper tapping and larger skin hole, and then have the hole covered when flying around. Could just use 500 mph tape.

What is the consensus on this?

Cheers, Pete

 

[sf3543]

I used a stainless eye screwed into the hole with a jam nut up against the skin. I only put these in when I needed to tie it down, since it didn't need to be tied down in the hangar. For all the other time, I installed a stainless machine screw with a hex drive pan head. It filled the hole and looked nice as well. Never had any problems with this method.