Category: Main Spar

So as I was doing a last double check on things and getting ready to start riveting on the top skin, something didn’t look 100% right.  I was doing the final check of the AN3 hardware to verify that I had torqued and installed torque seal on all the nuts when I realized that two of my wing ribs didn’t have any AN3 hardware installed.  Specifically the 2 of the outboard most ribs. (See photos below).

[inpost_fancy thumb_width=”200″ thumb_height=”200″ post_id=”653″ thumb_margin_left=”0″ thumb_margin_bottom=”0″ thumb_border_radius=”2″ thumb_shadow=”0 1px 4px rgba(0, 0, 0, 0.2)” id=”” random=”0″ group=”0″ border=”” show_in_popup=”0″ album_cover=”” album_cover_width=”200″ album_cover_height=”200″ popup_width=”800″ popup_max_height=”600″ popup_title=”Gallery” type=”fancy” sc_id=”sc1534549605819″]

Read more

Got a few more hours to work in the garage on my main spar.  I continued to countersink the various holes on the flanges of my main spar.  I’m sure I mentioned this in one of my Empennage posts, but I had previously had bad luck with the 3 flute countersink bits and opted to purchase some of the single-flute bits from Cleaveland tool.  In each bag that have a warning that its easy to break the pilot off of these countersinks if you apply a side-load on the countersink.  HA, I’m sure that warning is for other builders, not me!

Read more

Picking up where I left off I get the J-Channel prepped for the next spar.  This time I decided to pre-mark the 1/16 depth on the J-Channel to mark the alignment vs using my digital Caliper.  Pulled out the edge-marking guide I purchased from Cleveland tool and made quick work of it.

Basically a rinse-repeat of the previous update and quickly got the J-channel match drilled and set aside.

Next step was to get my countersink set up to make the appropriate cuts on the spar.  Reading the directions, it took a while for me to fully understand what was being described in the text.  Basically for ALL the nutplate rivet holes, you countersink them to just flush with the rib flange.  (also there are a few additional rib attachment holes between the nutplates that area also just countersunk flush.  Being slightly nerve-wracking I started SLOW and checked each countersink till I got more confident that I was doing things right.  (As always I started with a TEST piece before I worked on the spar!)

Once both spars had this level of countersunk done (13-3 step 2), I reset the countersink to accommodate skin dimples and begin to countersink all of the remaining holes in the spar flanges (13-3 step 3).  Easy enough and using a good countersink cage really helps to ensure you don’t screw up.

Once everything is countersunk, time to start installing the nutplates for the tanks.  Again, nothing technically difficult but did take the time to make sure that my rivets really sat flush prior to squeezing.  If they were just slightly proud, a turn or two with the deburring tool fixed the situation.  (Also plans don’t call it out but be sure to deburr the inside edge of the spar web)

I ended up skipping 13-3 step 5 for now since I didn’t have the right countersink (on order currently) and moved to installing the nutplates for inspection plates.  Again, nothing difficult.

EDIT:  Before you laugh at me, I totally misread step 5 and ordered a #19 piloted countersink.  Plans clearly state to “Drill a #19 hole and dimple for #8 screw.  Countersink with a #30 piloted countersink.”  Oops.   Read more

With all of the kit inventoried and stored mostly out of the way, I can begin working through the first section of the Wing Kit.  Starting with the Main Spars, I have to add on an extension piece and prep it for priming.  Nothing that I haven’t done before.  One of the decisions I made for the wing kit was that I was going to work on both wings at the same time vs completely finishing off one wing, then starting all over again on the other one.  Watching Jason Ellis and his youtube channel I think this is going to be the better way to go.  The only issue I may run into is not having enough space to work on two different wings at the same time.  I may end up working on both, then getting one wing complete to the point where it can sit in the wing cradle, then get the second wing to the same point.  One of those things I’ll honestly figure out as I go along.

Speaking of the wing cradle, Read more