Saturday, December 15, 2018

Final trim tab prep

 Started today by deburring all the trim tab parts starting with the skin holes.

 Then I worked on the spars.

 And the trim tab control horn assemblies.

 And the skin edges.

 Then I dimpled the trim tab control horn assemblies.

 Next I dimpled the bottom row of holes on the spar.

 And dimpled the holes in the skins.

 Then I countersunk the top row of holes in the spars per the directions.

 Next I primed the trim tab parts.  Control horn parts....


Next is on to assembly!

Thursday, December 13, 2018

More Elevator Trim Tab Prep

 Got started tonight by folding over the closeout tabs per the directions (sorta) by clamping them with the hardwood cutouts left over from the V blocks I made.  The process is the same for all 4 ends so rinse and repeat.  Be sure to radius the edges of the block that serves as the form in this process to prevent cracks!

 Bottom tab goes first.  I just used my fingers to start the bend then a small straight wood block to get the trailing end to start to fold.  Then I just used a small, flat, and smooth hammer to sloooowly tap the tab down and into place making the bend nice and clean.  A thousand lite taps is better than a few heavy ones!

 Then the top one gets done the same way.  It just folds down over the bottom one.

 Then I drilled the closeout tab rivet holes per the directions.  One side...

Then the other side...

 Then I bent the bottom of the skin to the 15° angle called out in the directions.  I wish I had a brake for this but all I have is hand seamers so my results are just OK not spectacular.

 Then I worked on preparing the trim tab control horns.  These get made out of two parts that must be modified by cutting off one ear of the horn.  I assume these are used on two different setups so Van's has us modify them for the particular application we need them for.  Mark and cut...make sure to leave the edge distance to the hole!

 All cut....

 Then smoothed on the large 3M Scotchbrite wheel.

Then I match drilled the trim tab control horn assemblies to the trim tabs.

Tuesday, December 11, 2018

Elevator Trim Tab Prep...

 Started tonight by masking off the area that gets scuffed up where the foam ribs glue in.  This takes a while to do right.

 Scuffed the area with 150 grit per the directions.

 Next I pulled the tape off and replaced tape over the area just scuffed.  This area won't get primed later to keep it clean for the pro-seal to glue in the foam ribs.  I went ahead and taped it off and also scuffed up the entire inside of the skin for primer due to the fact that it will be more difficult after the next step of finishing the bend in the trailing edge of the skin.

 I used my homemade brake to finish the bend in the trailing edge of the skins.

Then I checked my work by cleco'ing in the spar and checking how the skin was sitting.  No pillowing, puckering, and they are straight.  A straightedge from spar to trailing edge checks for ski jumps or humps.  These came out great!

Monday, December 10, 2018

Elevator leading edge rolling!

 Started tonight by rolling the leading edges of both elevators.  Not the most fun job but it has to be done.  I used the same PVC pipe I used on the 10's rudder and the emp parts of my RV-7 a million years ago.  It works!   I used fiber reinforced packing tape to tape the pipe to the skins.

 Then I twist it while pushing down.  I used pliers to rotate the pipe as far as it would go.

 Then I moved down to the other sections.  Flip it over and do the top side.  Then roll the other elevator the same way.

 Next I match drilled the #30 holes full size.

 All drilled.

 Next I put in the pop rivets.

All done.  I did the other elevator as well. Van's is really getting skimpy with the hardware.  I have 3 of these kind of pop rivets left over.

Sunday, December 9, 2018

Black Death!

 Got started on a snowy day finishing up the trailing edges of my elevators.  I am going to use this 3M VHB tape on the trailing edges similar to how I did the rudder.

 I finally am forced to get out the black death, AKA Pro-Seal.  I have this small kit that should be just enough to glue the foam ribs into the elevators.
 Buttered them up per the directions and inserted them in the elevators.

 After I placed all 4 of them, I moved on to clecoing the trailing edge to the VHB tape.  You can see I already have one side of the AEX wedge stuck in place at this point.

 I pulled the covering from the other side of the VHB tape and installed the cleco's thru the aluminum angle I made a while back to help keep the trailing edge straight.  Then I weighted down the skins where the foam ribs are to ensure good contact with the pro-seal.

 The VHB tape needs a few hours to fully stick according to the directions.  So I left that alone and moved on to trim tab stuff.

 I went to Lowes and purchased an oak board to make these trim tab fixture/jig things.  Marked them all.

 Cut them at the band saw.  The best of them will be used to help fold over the close out tabs on the skins.

 Next these templates have to be glued to the foam blanks.

 All glued.  Used spray glue.

 Then cut them on the bandsaw.

 After a few hours I then went on to squeeze the trailing edge rivets.  This is the flush manufactured head side.

 And this is the shop head side.

 Then I installed the pop rivets in the root shear clip and skins where they over lap.

 The way I got those results was to cleco the whole thing leaving out about every fifth cleco.

 I would partially squeeze about every fifth rivet.  Just enough to set it so nothing can move.

 Then I would go back and remove the cleco's in between the riveted holes and squeeze the rivets in those.  Then rinse and repeat until all the holes are filled with partially squeezed rivets.  Here is what it looks like before final squeezing.  The idea is to move around and not start at one end and squeeze them all in a row.  This is a guaranteed way to make a curve in the trailing edge.  Moving around spreads out the expansion created by squeezing.

 Then I go back and final squeeze.  I used a set of flat squeezer sets but put a small piece of the AEX wedge in between the set and the manufactured head of the rivet.  This makes the angles all align and works great.  Just don't over squeeze!

 The end result!

 Then I put the pop rivets in the other elevator shear clip.

Next I squeezed the remaining rivets on the outboard side of the elevators to the counterbalance rib.  The last one at the trailing edge on the bottom is a pain due to clearance even with the no hole yoke.  I just put a MK-319-BS pop rivet in there and moved on.  This is a Van's approved substitution.