Wing attach blocks

[142YX]

I believe AN-6 is a 3/8" hole.

Correct!

[sonex892]

I've been following this thread closely, as I am just now clamping my spars together to updrill.

I believe the question I have is directly relevant to this thread, so I will add it here instead of starting a new one.

I currently have the blocks at 3/16" and am mating the spars to updrill to 1/4" slowly in increments. I am set up to do this tomorrow morning.


Can someone please clarify what the final, last size of these holes will be when the wings are mounted and attached to the aircraft? Is the 1/4" the final size? I was told the final bolts are AN-6 and that would mean larger holes, obviously.

Robbie

The final size you go at this point depends on how you are going to rig your wings. Now is the time to make this decision.

For the sonex factory preferred piloted drill method dont go larger than 1/4". OR
For the bushing drill guide method, updrill the wing attach blocks on the clamped completed spars to 3/8". In a drill press before assembling the wings.

I just added a couple of drawings as pdf's in sonextalk files section, in a folder titled alternative spar drilling. Its a pictorial description of how to carry the drill bushing guide method. This method has been described in words numerous times before but I thought a drawings might help make it easier to understand.

http://groups.yahoo.com/group/sonextalk ... 0drilling/

I used the 3/8" OD x 1/4" ID bushing drill guide method and would do it again.

Steve
Sonex 892 VH-ZSX
3300 TD 118hrs

[Sonex1517]

Thanks everyone - that's exactly what I had been told - just triple checking since this is definitely one of those moments I want to get right.


Robbie
Sonex 1517

Sent from my iPad using Tapatalk HD

[jmtraylor]

Nick, you're not the only one to do this. I followed the up drill by 32nds technique and it bit me on the right side. I've since purchased the bit Kerry recommended and remade the blocks. I have yet to build the courage up to try again so I can't comment on how the new bit works.

Mark

[142YX]

Nick, you're not the only one to do this. I followed the up drill by 32nds technique and it bit me on the right side. I've since purchased the bit Kerry recommended and remade the blocks. I have yet to build the courage up to try again so I can't comment on how the new bit works.

Mark

Hi Mark..

Read on in the thread.. i document my rebuild and found that the recommended drill bit works great - i am a firm believer in this method now.

Its frustrating whey you are doing it, but you will feel great when you finish the repair. And you can't put a price tag on the piece of mind that it will give you.

Good luck with yours!

[vernd]

Hi - I am currently working on main spars, and about to do the initial drilling on the wing attach blocks at 3/16. I've read everything I can on this forum and on the old Yahoo forums hoping to prevent any issues with this drilling, as these are such critical holes further on in building. I also see there have been some issues even at this early step with "wallowing of these holes". Even tho there is a lot of good tips already shared, just looking for any further thots or bits of advice that I can use to make this drilling successful, and to ensure these holes line up for further match drilling when upsizing to 1/4", and then later wing alignment. Any suggestions much appreciated.

Thanks....Vern