Attaching Leading Edge Skin

Started drilling and setting the leading edge to the ribs/spar.  Here are some pictures of the progress.

I start my measuring and drilling the hole nearest to the spar (first pic) then measure out the remaining eight holes using a rivet spacing tool and square to draw a line and mark the locations.  Seems to be working out okay.  Measure twice - drill once is the mantra.

About two hours work for the first two ribs.  Of course I have been taking my time and the remaining ones should go a bit quicker.  Now that I have the mark, measure, drill, process figured out.

Thanks for checking in -

Greg.

Should I Re-do My Leading Edge Bend???

A bit of a pickle here.  I noticed my leading edge skin has a little "buckling" in the bend on the bottom side.  I don't think this is a problem.  It is a bit ugly.  How does this impact the aerodynamics?  I'm not sure.  I will get some input from the CX4 Builders Group to see what they think.  I guess for aesthetics it should be trashed and redone.  But then I've wasted a big chunk of costly .020 6061-T6 aluminum.

Anyone out there have any ideas or recommendations?

Does this call for a new bend?  I tried to push the dimple out but it didn't work.  

Going to delay drilling and riveting the skin until I can check with the designer and other builders to see if this is a problem or not.

Darn!

Greg.

Update - 9/10/13 - I asked Dave Thatcher (CX4 Designer) and he said "no problem - Just hit it with some bondo and it will be fine"  I may just do that.  Thanks Dave.

Marking Skin for Rivets - Measure Twice, Drill Once (or maybe measure more?)

Marking the rivet holes for the inboard leading edge rib.  Measuring per plans for 1.5" spacing I can only get eight (08) holes on a rib.  Hmmmm.  All the pictures I have seen and the plans show nine holes...

Here is my initial marking for the rivet positions at 1.5" spacing

Setting the 1.5" spacing with the rivet placement tool

That's marked on the center of the rib flange from just within the trailing edge to the leading edge end of the rib.  With the 1.5" spacing I can only get eight holes.  Is that enough?  On the plans the rivet locations indicate nine locations:

Plan clearly shows nine rivets on the top flange and eight on the bottom

I checked the plan and the first rivet location (at the spar) is just inside the trailing edge of the rib.  The second rivet location measures about 3/4" from the first.  Then they are evenly spaced at 1.5".  Even allowing for the 3/4" space between the first two holes I can only get eight.  I think the best thing I can do to meet the nine rivet requirement is to adjust the space between the rivets.  Maybe making the space 1.25" instead of 1.5" will work?  I'll try that and get back to you...

Thanks for checking in -

Greg.

Leading Edge Bending and Attachment

August 31 - Saturday

Spent a couple of hours preparing and then bending the left wing leading edge.  Used an 8' 2x4 to do the bend just like the instructions said.  Thought I was going to need help doing it.  I was able to do the bend and it was pretty easy.  I just used the 2x4 to press down on the sheet I cut to make the bend.  I then clamped and strapped the leading edge skin to the spar/rib structure.

 Pressing the skin onto the ribs after making the bend.  I first just pressed down on the sheet without the rib/spar structure to the initial fold/bend.  Then I placed the rib/spar structure into the skin and squared it.

 Here I clamped the skin to the leading edge.

Now I have to line up and mark the skin for initial drilling.  Then match up the ribs to the holes and cleco in place.  Will try to get that started tomorrow.

Thanks for checking in -

Greg.