Worked on the Tie-Down Bars - 2.5 hours

 I built up the courage to fix the oblong hole in the spar tonight. I bolted the whole assembly together including the aileron brackets. I then cut a piece of oak to fit between the brackets and clamped it tight to ensure nothing moved to drill the 1/4" hole for the AN4 bolt. Lots of time to set it up, but I wanted to make sure that there was no mistakes!
 I then set up the drill press. (no way that I am doing that by hand every again!).

Success, the hole came out really nice. I don't think I'll have an issue with edge distances but I will wait to hear back from Vans.
 
 I  received confirmation from aircraft spruce that my various selection of nutplates, AN4 bolts and washers are shipped. Should be able to finish this part off before long.
 
Next I finished drilling the K1000-3 nutplate for the one unfinished side (Once the new AN4 nutplates are in I'll tackle the last one) I then decided to tap the threads on the W-731 tie-down bar. I used my 3/8-16 tapered tap,  secured the tie-down bar in the vice and went to work. It was slow work but it went very well. The tapered tap just fit in the hole and the threads grabbed quickly. I used WD-40 to lube the tap as I went. I'd turn the tap about an 1/8th turn, then back, then turned it again cutting about 1/8 turn, and back, I do this a couple of times and then I'd blow out the chips with air and squirt in some WD-40. Every so often I would back out the tap, blow all the chip off the tap and out of the hole, and stick it back in. Takes a bunch of time, but I am very happy with the results. I tapped just about 1-1/4" deep. This allows a solid 1" of full threads while the tapered end made up the last 1/4".

Thinking day!

It's amazing how after a couple days, your mess up seems quite a bit less then what you thought at the time it happened! I looked at it yesterday morning and thought....it's not so bad. It should be fine.

I showed some guys at the EAA meeting last night about my conundrum and to my delight, each person had a warm smile. It's those moments that you learn....You learn a lot. First it tells you that everyone in that room has been there. It's a welcome to the club smile! Secondly - It's a smile that tells you 'Hey no worries, there's always a fix'. I tell you I felt like a million bucks after the EAA meeting. I've learned that's why you need to go to them.

Today I received an email from Sterling @ Van's giving his sage advice. Short and sweet - Upsize to AN4 and build on. The relief that I hadn't totally messed up was a bit short lived as I began to think my next move. First....order AN4 bolts, washers, and nutplates. Oh...which nutplate. I knew that K1000-4 was not going to work with the spacer. So now I have to think maybe a one lug, or a compact nutplate. Then...that led me to questioning edge distance on the parts. Oh man.
I should really figure out if edge distances play a factor on these parts.

Update: Called Vans to determine if edge distance was an issue. In short, they didn't think so but their answer was not definitive. It was a bit frustrating as the fella on the phone said I could leave the AN3 bolt with the slightly oblong hole. (But I have already drilled it out to AN4). Later in discussions with my friend who is an airplane mechanic would explain that edge distances are more critical with rivets than bolts due to the loads incurred when the are squeezed/bucked while bolts do not exert the same kind of pressures on the hole. He said that due to the nature of the part in tension that upsize to AN4 is alright for what I have done.




Build Tip - I've learned this so far. Think twice, act once. If you think once you will act 10 times more (worry yourself, and bug everyone around you). It's funny....I've not really messed up the hard parts (bending skins, bending tabs, double riveting the rudder trailing edge). I've just really messed up on the easy stuff. It's all because I've researched and thought about the tough stuff but paid no attention to the easy stuff. That's when it bites you.

Note to self - Remainder of build drill everything thicker than sheet aluminum in a drill press, or make a poor man's drill guide. That would have really saved my butt on this one.

Started work on the Wing tie-down brackets - 6 hours

 I started in on fabricating the W-726 Spacers for the wings. I drew up a template on autocad and transferred it to the spacers.

I marked the 1" hole center point and started with a #40 pilot hole to start. Then I opened up the hole to 1/4" Then I used a #5 unibit to open the holes up to 1" diameter. I double checked my dimensions and then cut the pieces. I was slightly larger than 2" so I ran them through the sanding station till I was satisfied.
 
 Then I got to work drilling them for the spar. I marked out lines on the spacers to ensure that they would be centered with respect to the holes on the spar web. I taped the spacers onto the web and used a hand drill with a 3/16" bit to start the holes. Once the holes where deep enough, I took the spacers over to the drill press and completed the 3/16"' holes. Very nice. Too tight for an AN3 bolt though. I then set up the Tie-down bracket according to the plans.

I drilled the first hole on the tie-down bracket with the drill press but I just could not fit an AN3 bolt in. So I upsized to a #12 bit. This time the AN3 bolt would fit through the tie down bracket allowing me to bolt it to the spar. I taped the spacers back down again and began match drilling the holes.

The left side turned out great, so I moved on the the right side. After the right side was drilled. I noticed that one of my holes was slightly oblong. My stomach jumped to my throat. Shoot.
This must have happened when I taped the spacer back down to the spar. The tape had held the spacer just slightly off and good enough to let the drill bit dig into the spar. At its widest point its 0.207" across. Enough to raise my eyebrows.




Another look






The holes in the Tie-down and spacer are good. With good bolt fit through them.



 
I'm hoping that I will be ok as-is, and that I haven't done anything serious. Truly a silly mistake. The thought of going up a bolt size crossed my mind, and I double checked if a K1000-4 platenut will fit on the spacer but it won't. I might have to buy a special compact or one lug platenut if I have to go to and AN4 bolt.

Update. Van's recommends up-sizing to an AN4 bolt here. 
Note to self for future....Drill these holes with the drill press!

Finished counterskinking the Wing Spars - 6 hours

After finishing the HS#2 (My big goal) I was happy to jump back onto the wings and keep moving forward. I continued on with the #6 access plate countersinks. Satisfied with the 0.300" diameter of the countersinks, it took no time to finish the job.




I then moved on to the #8 screw Tank attachment holes. Reading the forums and the blogs I decided to go right in the middle of the recommended countersink diameter at 0.370" Took a while to dial it in, but once I did...I was off and running.




After that was finished, I did the 8 holes for the K1000-4 nutplates. Checked, checked and re-checked to make sure I was countersinking the correct side.

Finished riveting the HS#2 - 3 hours

I woke up this morning excited to get going on finishing the HS. Just a couple of quick hours of riveting and I am done! Ready for the pre-close inspection....Again.


 In retrospect I am way happier with the second HS. Its extremely clean, not a single oops rivet (Although I still have to rivet it closed after inspection - Knock on wood), Once I have completely riveted though I will weight it against the first one. I suspect the first weighs considerably more due to the 2-part epoxy.

Started riveting the skin on HS#2 - 4 hours

Took a bit of a slow day today. I cleco'd the skins to the HS-707, HS-708 and HS-706 ribs. I then proceeded to rivet the skin to HS-707 both L and R sides.

I then deviated from the plans slightly as I riveted the HS-706 to the front spar assembly. The plans have to do this step after the skins are riveted and the first go around was really tough for my to get a good bucked rivet in that tight space. I then set the assembly into the skins and re-cleco'd everything.
 
Began the long, but quite enjoyable task to rivet the skins on. Managed to get a ways through before I called it a day.

Started riveting the HS#2 skins - 2.5 hours

I dimpled the skins (which actually takes a bit of time) on the DRDT-2 and then set starting to rivet the skins. So far....So good.