HS Spar Hole Sizing

The drawing calls for AD4 rivets in the locations discussed, but the instructions say to drill #40 holes in the last checked item and the first unchecked item. These are from 6-3 referring to the HS drawings.

Shouldn't we be match drilling #30 here? I don't see anywhere in the instructions later before riveting to upsize from #40 to #30.

I just noticed on the second step under "Drilling the Horizontal Stabilizer", it says to drill #40s there as well.

here are is where the rivets go, I don't know how the original HS is built now, this was a drill apart and add forward spar stiffeners. O ya, there is a top and bottom to these stiffeners, take out your calipers and measure.

It is common throughout the plans to first drill to #40 for fitting parts together and later going to the size required in the drawing. It is not clear from your photo what they want in the next to the last step.

Farther down the page they talk about match drilling flanges to the skins, and a couple other things, but not this point in particular. I guess it makes sense to start #40 and then go #30, as going right for a #30 might wander a bit.

I did indeed install my HS-0001 upside down and match drilled that way into HS 710 and HS 714. The holes aren't straight along those pieces, but they have the 2xd edge distances required, and I sent a pic to Vans and they said I am OK. From now on anything that looks symmetrical, I will measure and double check. It was on the plans, but didn't notice "up" till afterwards.

From now on anything that looks symmetrical, I will measure and double check. It was on the plans, but didn't notice "up" till afterwards.[/QUOTE]

Thank you guys for the post, missed the UP as well.