Rudder and VS and the unpleasent truth

The vertical stabilizer and rudder is finished. I washed off the excess zinc chromate with acetone, leaving only zinc chromate at the mating surfaces. I guess a very practical feature with single component primers is that they easely can be washed off, and that is also a bad thing. Single component is nowhere near as tough as epoxy based primers. The rod end bearings must be adjusted, but this job requires two persons. With the VS and rudder finished it is definitely going forward.

But things are also going backward. During the time the HS was in the jig, the wood in the jig changed shape, probably due to changes in temp and moisture with changing seasons. The result is that the hinges on the HS do not line up. The error is approximately 5 mm. To get it right I would have to shim each tip hinge bracket approximately 5 mm out. This is a lot. It will not look good, and it will also mean more forces on the HS spar. I have a set of usable skins, and have decided to replace the skins on the HS. Just to take them off without damaging the skeleton, will take a lot of time. This will be the third time I fit the skin on the HS, and the third pair of skins.

Rudder, leading edge

Finished the leading edge of the rudder. Need to debur and prime before riveting.

Riveted on the rudder skin

The rudder skin is riveted on the rudder skeleton. I used Cherrymax rivets on the control horn. I need to get a pipe wrench tomorrow to bend the leading edge into shape. I thought I could do it by hand, but it is way too strong and I just can't get a good grip on the pipe.

Stiffeners elevator, Rudder

Finished drilling and deburring the stiffeners on the left elevator. Started again on the rudder. The skin has to be riveted on to free up some clamps that is on the rudder jig before doing anything else.

Rudder and elevator

I was going to prime, but run out of gloves. Have to put pop rivets (LP4-3) in R-410 because none of my tools fit inside, and I have already riveted the assembly together. Due to some drilling difficulties, I will have one 4/32 and one 5/32 solid rivet, and two LP4-3 rivets. This looks strange, but is perfectly OK.

Elevator skeleton and priming

Made the skeleton for the right elevator. Primed the skin, stiffeners, skeleton and the rest of the bits for the rudder.

Elevator and rudder

Finished the rudder. Deburring and dimpling and fine trimming. My controller has to come and look at the rudder and VS before I rivet on the skin.

Started on the right elevator. Measured up and fabricated the stiffeners.

Deburring and dimpling

Dimpeld the rudder skin and skeleton and deburred them.

Drilling the rudder

Marked all lines and holes and drilled the rudder skin to the skeleton. Also made the strips to fasten the fiberglass trimming and details.

Fixing rudder

Finished trimming the rudder skin. Cut out the slots for the hinges. Used cutters for a rough cut, then a dremel for the rounded corner and a file to get straight edges.

Trimming rudder

Started trimming the rudder for hinge points etc.

R-410

Time to do some work again. Started with cutting and filing R-410 into shape. Spent some time studying how to cut/trim the rudder, but I'm still not completely sure in which sequence this should be done.

Bending the rudder skin

Bended the rudder skin and started mounting the rudder jig. There is a lot of trimming to do on the rudder, and I need to mark all that before assembling (I'm not entirely sure if it is best to cut everything before riveting). Ordered "RTV 3145" from Aircraftspruce, probably the most expensive glue ever, 33 US$ + shipping for 4 oz (118 ml), a Christmas gift all by itself, he he. This is needed at inside the trailing edge of the rudder to prevent cracking.

Rudder skeleton riveted

Riveted together the rudder skeleton. At first it seems like the rudder is fastened to the rod end bearings with only two rivets each, so that only six 2/16 rivets are holding the whole rudder. But when looking just a bit more closely, the rod ends are really holding the rudder with the bearings and the rod end nut squizing the plates and spar together. The six rivets are only there to keep the jam nut positioned. Nice design.

The jam nuts on the rudder seemed to be bare steel, so I primed them using the zinc chromate rattle can.

Primed the rudder skeleton

Primed the rudder skeleton parts with the P05 Strontium Chromate Epoxy. The aluminum plate from Sweden arrived within a couple of days last week.

Finished rudder spar

Deburr and priming next, I think.

Rudder spar assembly

Fixed the rudder spar lower assambly. Lots of drilling through lots of pieces. Two holes left in the R405 + the top spar before deburr/prime.

The aluminium was sent from Sweden. Certainly much cheaper than sending from the US, I wonder how long it takes.

Hinge support plates

Drilled the hiinge support plates.

Adjusting rudder hinges

Drilled holes in the rudder spar and started adjusting the holes for the hinge bolts.

R-405

Fabricated the R-405. Piece by piece ...