horizontal stabilizer atttachment to fuselage

I was leaving a lot of the airframe stuff until I had some of the more fiddly jobs like wiring etc. done. I'm stuck towards the end of wiring and sick of it. So I'm heading back to some "real" aeroplane building. It's good to be actually doing something after many years of very spasmodic building.

I'm attaching the horizontal stabliser.

It's all aligned to within about 1/32" (insofar as you can do such a measurement that accurately) and nicely levelled.

I've drilled the outboard holes attaching the HS to the fuselage with a long #40 drill. I was able to get the holes nicely vertical and comfortably keep all the edge distances. Everything is still well aligned and level and I've got some clecoes in those two holes holding everything in position.

I've now come to drill the inboard holes. I don't have the plans in front of me but I believe it's plan 48 which shows they are 1 1/4" inboard from the outboard holes. I have marked them and predrilled them in that position on the HS forward spar. But I'm looking for an effective way of drilling through the predrilled holes into the fuselage now.

I've got a QB kit from about 2003. It has the top of the fuselage attached all the way back to the rear deck where the empennage attaches.

That makes it virtually impossible to get to the the holes even with a right angle drill. The top flange prevents getting to the holes vrom the vertical. The top of the fuselage prevents getting the right angle drill atttachment to the holes from the forward direction. Practically how do I get it in there to drill these holes.

It looks like I will have to crawl right up to the back of the fuselage or put a helper in there to hold and operate the drill while I position the right angle attacment and align it in each of the inboard holes to be drilled. That seems to me to have all sorts of possibilities for error.

Another option seems to be to drill some holes in the upper flange of the front spar above the holes to be drilled in the lower flange and use a long drill to go straight into the holes to be drilled in the lower flange. But I want to avoid putting holes in the top flange if I can...but perhaps I'm just being too sensitive about that.

Can I please have your ideas about how to accurately drill these holes in this tight little spot?

Thanks

I didn't have a quick-build when I drilled these holes but I did have the F 810A (rear most turtle deck bulkhead top) installed.

In order to get to the area to drill it (as one of the pieces of angle on the HS interfers with drilling) I removed the F 810A and then later put it back in place.

The only thing I can think of is a flexible or angled drill.

http://www.averytools.com/prodinfo.asp?number=9751

http://www.google.com/products/cata...nmYcTuX2CcT30gHAoZzGBw&sqi=2&ved=0CFoQ8gIwAg#

http://www.google.com/products/cata...=X&ei=0WYcTtPsE8up0AGf2MzqBw&ved=0CF8Q8gIwBA#

-Jason

kens_cockpit said:

.....I'm looking for an effective way of drilling through the predrilled holes into the fuselage now.....your ideas about how to accurately drill these holes in this tight little spot?....

Click to expand...

There is a tool that is just the ticket for accurately drilling the holes you describe. The tool has served me very well over the years and is available either as a chuck-on attachment or dedicated drill motor. Google "Pancake drill" for more information.

Pancake drill

That was soooo cool I bought one even though I didn't need to... 40$...