Are these good enough?

[rizzz]

Hi All,

I rigged my wings this weekend and I just wanted to show you the end result and see if you think the results are good enough.
I followed the standard method using the special 3/8” drill bit with 1/4" pilot, the pilot was significantly dulled.

After I finished I test fitted the bolts and they need significant encouragement with a hammer to get them in and out, everything seems quite snug. When I took the wings back out and test fitted the bolts again I did find they are a little more loose on the forward vertical angle compared to the aft angle, the forward side is obviously the one from which I did the final drilling (as per the instructions) and I guess pushing/pulling the drill bit in/out constantly to clear out the hole might have slightly enlarged the hole on the forward angle.
It is really not significant and as far as I can see the holes are perfectly round, but there is a noticeable difference between the fit in the forward hole compared to the aft one.

Anyway, what do you all think, are these good enough?









BTW, you can find much more pictures of the whole process on my kitlog site:
http://www.mykitlog.com/rizzz

[rizzz]

BTW, all the mess is cutting fluid, need to clean that up still...

[MichaelFarley56]

Looks perfect! Those will work great!

Nice job and congrats on finishing that important job.

[fastj22]

When you pin both wings, is there any slop? If not, you did good.

[rizzz]

No slop at all, wings a firmly held in place and the bolts need some (harder than expected) blows with a mallet/hammer to go in/out with the wings in place.

[fastj22]

The real test will be first flight when you verify your rigging was true.
One great feeling I had was shortly after my first takeoff, being able to release the stick and feet off rudders and she tracked true.
Congratulations. Big milestone.

[rizzz]

The real test will be first flight when you verify your rigging was true.
One great feeling I had was shortly after my first takeoff, being able to release the stick and feet off rudders and she tracked true.
Congratulations. Big milestone.

Ha yes, that first take-off. Surely after reaching this milestone it can't be too far away now :-)

[tonyr]

Congratulations Michael

Looks good
Tony

P.S. The rivet that you pummeled for clearance of the bolt/nut can be drilled out and reinserted from the inside. Once the wings are on you won't see it.

[rizzz]

Congratulations Michael

Looks good
Tony

P.S. The rivet that you pummeled for clearance of the bolt/nut can be drilled out and reinserted from the inside. Once the wings are on you won't see it.

Thanks Tony,
Yes I quickly ground away most of that rivet as it was in the way but was intending to drill it out completely later and install from the inside, probably the one above and below as well. I have even seen pictures (on this forum I think of people installing flush rivets from the inside here but I don't think that will be necessary in my case.

[rizzz]

It would appear the holes were not good enough at least on the forward side, I think I’ve just been in denial the last week or so, not wanting to see the truth.

It is not really visible from the pictures here but there is too much movement in those forward angles, I made a couple of videos of me wiggling the bolt in the hole and Kerry says I need to remake the parts with enlarged holes or upsize the holes.
I also put the wings back on this weekend and got my friend to move the wings while I examine the movement of the bolt, You can’t see the wing move relative to the fuselage, that seems rock solid, but when you look closely at the bolts on the forward side, slight movement can be detected, at least on one side.

I’ve put a video on my dropbox account, I guess it’s best to share my experience with everybody so others can learn from my mistake. This will at least show you what is not good enough.
As this is my personal dropbox space, this video won’t be there forever, download it now if you’d like to keep it for future reference.
The video first shows the AN6 bolt in the spar box without the wings installed, You can see me moving the bolt in the hole forward angle, then I switch to trying to move the bolt in the aft angle, this is pretty solid, no movement at all, then I switch back to the forward angle. Finally, notice I install a different bolt in the hole, this is a metric 10mm (0.394”) bolt, at 0.019” larger this bolt seems to match the hole perfectly so that gives me an idea of how much this hole has been enlarged. Anyway, here’s the link:
https://www.dropbox.com/s/x2q73fj1i02w4c7/IMG_0717.MOV

So, I have 2 options now:

1. Re-make the forward vertical fuselage angles & forward wing attach block assemblies, re-mate the spars using a 3/8 – 1/4 bushing, reinstall the wings and updrill aft to forward this time. The holes in my aft vertical fuselage angles and aft attach block assemblies are perfect so no need to re-make those.

2. Updrill the hole for a larger bolt, given the perfect fit of a 10mm bolt as shown in the video, updrilling/reaming to 10mm is looking really tempting, given it’s only a mear 0.019” I might actually be able to take the attach block assemblies off the wings, take the angles off the fuselage and ream each one out individually on the drill press. With only such a small amount to ream away I don’t believe there would be any issues doing each part individually and then rematching everything back together.

I’m not sure which way I’ll go yet, option 2 is certainly the “easier” option and Kerry agrees this can work if executed well, but if I screw it up I would then have destroyed my aft angles and attach blocks as well. From that perspective option 2 is more like the risky “easy way out” option, I’m going to do some practice runs with my 10mm reamers to see how big the risk is.