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Section Hours: 116.2 Section Status: Complete



July 3-5, 2006:  With the holiday and all we've been a little slack with logging time.  We've only been able to get out in the shop off and on and rarely did it involve taking pictures of our progress.  The majority of what was done was busy work (deburring, dimpling, etc) and we had a few "issues" that were less than motivating.  So here's a brief look at some of it...


July 3, 2006 (9-16 step 5):  I tried my hand and got quite frustrated with the trim tab closeout tabs on Monday.  The first bend was a breeze.  I had forgotten the double sided tabe Van's calls for in the plans to help aid holding the wedges in place during the process.  I didn't have any problem though.  On the second bend I decided to go ahead and use the tape 'just in case'... turns out that was a bad idea (explained later).  As you can see the results were less than stellar.  As I was tapping the second bend around the first one the wedge was being pushed inward and I didn't realize it for a bit.  This in effect caused the bend in the first tab to move inward also (following the wedge) resulting in more material being forced into the tab until it eventually met the opposite skin.  Once this happned the only other place it could go was the opposite direction which was to push the bend down (as you can see in the picture, although the piece has been turned over).  This is when I noticed what was going on.  A couple of crappy attempts to fix it did nothing, and I finally decided I needed to walk away from this for now...
July 4, 2006 (9-7 step 9):  Angela did a lot of the hole deburring and dimpling.  She got the elevator tip ribs and counterbalance skins taken care of.  We deburred the edges of the skins and then scuffed the inside surface in preparation for priming later.  Here Angela is dimpling one of them.




Unfortunately we had a minor setback during the dimpling of one of the skins.  The lever arm of the DRDT-2 dimpler was swung all the way up (at least we thought so) while the skin was being adjusted to line up the next hole.  Apparently the arm was nearly vertical with a slight lean towards the direction of coming down... well, gravity finally took over and down it came under its own weight, and we didn't quite have the hole lined up in the dimple dies yet.  These elevator skins are only .016" thick so it doesn't take much to bend them.  It put a nice little dimple slightly offset to the side of the hole.  No problem, we'll just redimple it in the correct location... so that's what we did.  Unfortunately either the original dimple or the second one created a crack in the skin radiating out from the hole past the edge of the dimple.  Bummer!  Ideally the crack would only extend away from the hole a distance that would allow us to drill the hole out (taking the crack with it) for the next size rivet.  Unfortunately thats not the case here.  The next size rivet up is shown in the pic for reference, and drilling the hole out and redimpling for it won't remove all the crack.  A quick email and a copy of the pic to Van's requesting possible fixes wasn't very promising either... we can either replace the skin, or "just rivet it (maybe with an extra rivet nearby) and move on".  Hmmmm... I'll leave the interpretation of that to the reader... but for me, it doesn't leave me with a warm fuzzy.  We're really trying not to replace the skin either, so it was off to do some research for some other possible fixes.  Based on some of the things we've found our current thinking right now is we'll leave it as is, and during final assembly apply some proseal between the spar and skin in this location.  This hopefully will dampen any crack inducing vibration in this area.  We've got an email out to our tech advisor suggesting this, so we'll see what he thinks about it.
July 5, 2006 (9-16 step 5):  Ok, feeling a bit rejuvenated, I decided to tackle the trim tab closeout tabs again.  There was a lot of trial and error here, but I eventually figured out that the tape was almost acting like a lubricant in a way.  Sounds weird I know, but with the tape, the wedges had a tendency to be squeezed out... without it, I never once had any problem... period!  Needless to say, I didn't use the tape anymore.  Once I figured this out, and got a technique down, the remainder of the tabs were relatively painless!  I basically did them just as the plans call for:  bend with a block by hand, and then follow up with a flush rivet set in the rivet gun.  I think I had the pressure down to about 12 or 13 psi and only held the trigger about a half second at a time.




(9-17 step 4):  Back in a good mood about building again I decided to truck on with the trim tabs.  Now that the closeout tabs were bent the next step was to cleco the spars back in and match drill the holes in  the closout tabs.  The next step in the plans called for removing the spar and bending the lower skin.  However, right after that you put the spar right back in.  Not seeing any reason otherwise, I decided I'd bend the lower skin after I had done everything I needed to do with the spar clecoed in place in order to save me the time of pulling it out and putting it back in again.  So, with the spar still in I clecoed the trim tab horns in place, and final drilled them.  This plans aren't quite clear if they mean for you to final drill all the skin holes to the spar as well.  After reading through all the trim tab plans I finally decided I needed to so here I'm final drilling the skin holes to the spar.




(9-17 step 2):  The last step remaining in the trim tab preparation was to remove the spars and bend the lower edge of the skin up 15 degrees.  These tabs will be attached to the rear spar of the elevators by edge of the skin.  Putting this bend in the lower skin allows it to clear the elevator rear spar flange when the trim tab swings down.  This wasn't exactly easy, and again time consuming.  It's pretty late, so I'll sleep on it, and try and figure out a better way to do the other one.
July 6, 2006:  We heard back from our tech advisor regarding the cracked skin from yesterday... he seemed to think the proseal idea should be sufficient, or at least provide enough buffer to give us time to notice and rectify the issue should the crack start propogating in the future.


(9-17 step 2):  Ok, I must have been tired last night because I bent the lower edge of the second trim tab skin tonight using the exact same procedure and it took all of about 10 minutes!  Next I deburred all the holes and made sure all the edges were deburred.  While doing this the portion of the skins aft of the tabs appeared to stick out way too much (left)… I just didn't like the way it looked so I sanded them down (right)… mainly just for appearance.  It doesn't bother me as much now ;-)




(9-17 step 6):  Once all the trim tab pieces were deburred, next step was to countersink the upper flange of the spars, and basically dimple eveything else.  Unfortunately our 1/8" dimple die (needed for the #30 holes in the closeout tabs) is relatively fat and will not fit in the space available for the closeout tabs.  We'll either have to shave our existing dimple die down, or see about getting a thinner one.  We'll see...
July 7, 2006:  We ordered Rivethead-Aero's trim cable anchor brackets (left) to replace Van's WD-415 (right).  The Van's supplied brackets are nothing more than a nut welded to a small piece of sheet.  Numerous reasons to ditch these and go with the others, but the main ones are:  1) they're available, 2) solid billet vs a tack weld, 3) they just simply look better!




(9-7 step 4):  The brackets will get mounted to these cover plates.  The brackets are used to anchor the end of the trim cables where they exit the elevators.  First step is to mark the location of the brackets…




(9-7 step 5):  The brackets then got clamped to the cover plates and the holes were final drilled in the plates, removed, and debured.  After that, I put all the dimples in the cover plates, the reinforcement plates, and the nut plates.




The last thing for the night was to go back through the plans and verify that we were ready for priming.  I had forgotten the dimples in the closeout tabs of the elevator skins and the trim tab skins.  I held off on these because we didn't have a small diameter dimple die.  I picked a couple up today at lunch from Avery Tools, and finished the skins up tonight.  Now, all we need to do is alodine, mask the skins and then prime!
July 14, 2006 (9-7 step 5):  I got to looking back at the cover plates and, like many before me, wondered why Van's calls out pop rivets for attaching the anchor brackets to them since access is not an issue.  Angela & I discussed it and figured it was probably because of the lack of space to place 4 rivets on that tiny peice of sheet.  Getting 4 rivets in there is one thing, dimpling them for countersunk rivets is another.  So, after making some checks we decided we could countersink our new billet brackets, and dimple the plates to accept countersunk rivets.  This will make for a much nicer installation.




(9-10 step 1):  Ok... on to the 'fun' stuff... actually that should probably say 'necessary' stuff... but I'll probably get some disagreement from some there too... Anyway, since I hate sanding we're going to alodine everything but the skins this time, mainly for surface prep purposes, but the warm fuzzy we get from the corrosion resistance standpoint doesn't hurt either!  Everything will fit nicely in exactly 1/2 of the long spar empennage box our kit came in so I rigged up a way to fill one half of it with alumiprep, and the other half with alodine.  Getting the chemicals in it is easy, getting it out was the issue.  I basically scoop as much of it out as I can with a cup, and then the last bit exits through a removable panel I installed in the bottom of each end.  The plastic liner is taped in position over these panels, and when its time we simply remove the panel, pull the tape off and drop the plastic down through the hole.  The liquid runs into a bucket waiting below.




After all the parts were hung up to dry I went on to mask off the areas of the skins that needed to be kept free from primer.  Here you can see the inside of the trim tabs where the foam ribs will be glued in.




And here are a couple of the skins with the trailing edges masked off for foam ribs and also where the AEX wedge will be sealed in (just like on the rudder).  Also, on the upper left of the skin in the foreground you can see the spot I've masked off for the cracked dimple.  This is where we'll seal the skin to the front spar and rib in that area.
July 15, 2006 (9-10 step 1):  Next step was the priming... my favorite part :-/  The screen door (foreground) works well because it allows air to pass through making it less likely to blow light parts around (and some of these parts are very light!)  I think we're going to see about getting another one since the parts count is usually more than one can hold.  Also, since we're going to need some saw horses for the tailcone we talked about getting them now and using them to elevate the screen doors to a more workable level... so I don't have to do all this 'back-breaking' priming as you can see ;-)




Once the priming was done I removed the tape from the masked off areas.  On the right you can see the spot that was masked off for sealant where the cracked dimple is.




(9-10 step 3):  Alright… now that the priming is done, the fun begins… lets put some stuff together!!  First step is to rivet the inboard and outboard tip ribs together.  After that, the thin strip of skin that goes around the tip ribs goes on.






(9-10 step 7):  While I was doing the tip ribs, Angela came out and started clecoing the spars together because the next step was to rivet the hinge reinforcement plates and nutplates to them.  After that I riveted the root ribs on, followed by the elevator horns.  Not a whole bunch assembled tonight, but this is where we're going to have to call it a night... way past my bed time!
July 16, 2006 (9-10 step 6):  Today I don't have a whole lot of time to devote to building, so I plan to sneak some in wherever I can.  My first covert garage ops involved gluing the trim cable snap bushings into the elevator front spars.  For odds and ends sealing jobs like this I'm using an adhesive adopted by a lot of builders, E6000.  This stuff is about $3-$4 at the local crafts store.




(9-11 step 3):  Next I installed the nutplates on the trim cover reinforcement plates, and then backriveted the plates onto the skins themselves (the plans actually swapped the rivet callouts for each of these).  After that I was off.  Angela decided to take over while I was gone so she jumped in and started backriveting the elevator rib halves to the skins.  She breezed through one pretty quick but then hit a snag on the second.  Unfortunately she found out the hard way about paying attention to the plans (sometimes hard to do since they're vague & incorrect in some places, but every once in a while they'll sneak a single word in that makes a HUGE difference).  You see, each rib is made up of two halves.  One half is made up of the side flange that mates to the skin, the front flange that mates to the front spar, and the rear flange that mates to the rear spar.  The other half is made up of a side flange that mates to the opposite skin only.  Intuitively she thought that if the smaller half of the rib mounted to the lower skin on the left side, then the same would be true on the right side.  In reality though, the opposite was true.  The reason this is done is to keep the webs of the ribs facing inboard, and the flanges pointed outboard.  Well... the real bad part of this whole deal was she didn't notice it until almost the entire skin was done (double DOH!)  So, while I was gone Angela managed to backrivet 7 rib halves (56 rivets)... and then drill out those 56 rivets!!!  I know I shouldn't have, but I gave her a hard time about feeling like she had to outdo me on the number of drilled out rivets... I might need to make that one up to her :-/  The impressive thing is, she got all of that done before I returned, and if she hadn't have said anything, I might not have known (she did a good job of drilling them out!)  Anyway... I was motivated to get back at it, so I jumped back in and fastened the remaining rib halves to the 3 remaining skins... that is except for the one that's near the skin dimple that contains the crack.  We'll apply some proseal to that one later so I'm holding off on attaching that rib half for now.




(9-11 step 6):  After the rib halves it was time to attach the rear spars to them.  I could get away with this now because the rib half that's not attached yet is one of the ones that doesn't have the flange that the rear spar attaches to.  While attaching the rear spars my original intent was to place the manufactured head of the rivets on the aft facing side since part of this will be potentially visible.  However, after squeezing these the shop head caused the flange to curl up slightly even though it was fully seated to begin with.  So I turned the remaining rivets around and no more problem.




(9-12 step 1):  Once the rear spars were on then the shear clips and gussets were attached to the rear spars.  After that I wanted to sneak one more thing in before bed.  The next step was attaching the skin to the rear spar on the right elevator (not the left one though.  Half of those rivets are also used to attach the trim tabs, and that is done near the end of the assembly)  So anyway, I squeezed the rivets I could on the right skin, and left it at that.  Tomorrow Angela & I will buck the remaining ones on this skin (the squeezer won't reach).


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