Updrilling Mated Spars

[Gunther]

Hello to all. I have clamped the spars together to updrill the spar blocks from 3/16" to 1/4" and the three alignment holes from 3/32" to 1/4". Can the updrilling be done by hand or should I use my drill press? Should I up up drill in small steps such as 1/64" or 1/32"? Any special considerations or cautions that I should watch for?

Thank you,
Gunther

[Sonex1517]

Hi Gunther

As always, Sonex tech support is the one to ask.

My personal experience is to updrill directly from 3/16" to 1/4" with the spars mated and clamped. Be certain the drill bit enters at a perfect 90 degree angle. (I know how important it is because I failed to do this properly)

Once this is complete, using a high quality piloted bit to go directly up to 3/8" is the recommended process. Several specific piloted bits have been discussed in recent threads.

There are numerous techniques that work, so you need to find what works best for you - the factory strongly recommends following the plans. Others have different methods that also work but do not follow the recommended process. There are links to those methods in other threads.

I just finished my wing rigging yesterday. It took me three tries but I got it done!

The Sonex Foundation offers a tool loan program if you need a piloted bit.


Robbie Culver
Sonex 1517
Chicagoland
Tails and Wings complete - finishing fuselage.
N1517S reserved

[Sonex1517]

Gunther

I should have added I was referring to the wing block holes to updrill directly.


Robbie Culver
Sonex 1517
Chicagoland
Tails and Wings complete - finishing fuselage.
N1517S reserved

[rizzz]

I updrilled from 3/16 to 1/4 directly on a drill press.
My little drill press did not have the stroke to push all the way through so I borrowed one from a friend, it was bigger than mine but still did not reach all the way through.
I resolved the issue by inserting the drill bit initially as far as I could in the drill, install the mated spars perfectly perpendicular to the drill bit on the drill press, drill as far as I could into the blocks/spars, retract, loosen the drill bit and now move it as far out of the chuck as possible and tighten again, then drill through the last bit of material. Worked great.

Personally I'd be a little hesitant to do this by hand, I would just be too scared to stuff it up,
But, I've seen it done so I know it works, (here for example: http://www.synelec.com.au/sonex/showcon ... ings/spars, scroll all the way to the end of the page),