Logistics – Jigs, Air

The electrical power went off for quite a while today at our house and at the boys, as heavy thunderstorms and high winds knocked down trees and power poles around the area.  Our internet connection was also down for about an hour. Tornado warnings were issued for Wake County, so not much work was done directly on the plane.  I did use the time, however, to stage and later assemble a few logistical items.

IMGP3690Many RV10 builders recommend using a piece of angle iron for both jigging and back-riveting the trailing edge of rudder, elevators, and ailerons.  I had a six foot long section 1.75 inch wide, perfect for this application.  Here I am measuring for the attachment holes.

 

 

 

IMGP3693The plan is marry the angle iron with a 2×4 for clamping onto the workbenches.  Making the combined unit removable will help with flexibility in the cramped shop space.

 

 

 

 

IMGP3696The holes are recessed in the front side wood face to allow the bolt heads with washers to be flush with the surface.

 

 

 

 

IMGP3698Clamped on the workbench side the angle iron can be adjusted up or down relative the the top.  Before using the unit to align the rudder trailing edge, I plan to belt sand the iron and the married 2×4 wood.  This will ensure they are absolutely flat,  plus removes rust from the old iron surface.

 

 

 

IMGP3702Also spent time with the power out to assemble the Ingersoll-Rand ARO 1000 Series air filters and regulator.  (l-r) 5micron filter, 5micron filter, 0.3micron coalescing filter, and 160psi regulator. The goal is making sure no dust, oil, or water gets to the spray gun for priming/painting. These small units supposedly can handle ~50cfm of air, much more than the 5cfm needed for my Asturo ECO/SX gun.

Rudder Drilling – Part 2

Used a chart and homemade guide to get the necessary 5 degree angle to drill perpendicular to the chord line as per instructions.

IMGP3685A rough drawing of the trailing edge configuration.

 

 

 

 

IMGP3687Home drill guide in operation.

 

 

 

 

IMGP3688Drilling in progress.

 

 

 

 

IMGP3689This close-up shows the trimmed trailing edge.  A bit more rounding is needed to smooth the AEX piece.  I intend using ProSeal (or equivalent) on the trailing edge, so hopefully some of the empty space will get filled with this material.

Rudder Drilling – Part 1a

The last few days I have been researching how to drill and countersink the rudder trailing edge.  By hand measuring the AEX aluminum strip I determined the acute angle to be about 10-to-12 degrees.  If the common drilled hole through both sides is perpendicular to the chord, this means the countersinking bit will be about 6 degrees off the drilled line when removing material to accept the skin dimples. This angular difference does not seem like much, but we shall see how it goes.

I have also spent quite some time finalizing the bonding strap and static wick configurations.  Using #10 screws, nut plates, and a 3/8″ braided copper mesh should do the trick for effective electrical connectivity.  My intention is utilize the open area near the middle hinge for the bonding strap.  Parts were ordered and have arrived from Aircraft Spruce.

MISC LOGISTICS – continue to acquire painting supplies and work on the configuration of the shed for alodine/prime processes.  I have my eye on a 7.2CFM, 2HP air compressor, but need our finances to stabilize a bit before pulling the trigger.

Rudder Drilling – Part 1

Eric helped match drill all the rudder skin holes common to the spar and stiffeners.  I do not understand the instructions drilling the trailing edge. In one step the plans call for drilling perpendicular to the chord of the rudder, later it talks about countersinking holes perpendicular to the trailing edge surface.  Right now these seem like contradictory instructions.  I will need to get some clarification before proceeding.

Rudder Skins

The rudder skins were prepped and rigged ready for match drilling (Sections 7.6.3 – 7.6.5)

IMGP3662Today I used the soldering iron trick to cleanly peel away vinyl from the edges and rivet lines on the exterior side of the skins.  There is a big debate in the community about the utility of leaving the vinyl on (scratch resistance vs. corrosion potential), but I think it looks cool.  Besides the plane parts are currently stored in our climate controlled bonus room, plus I do not intend to spend decades waiting to process and corrosion treat these materials.

 

 

IMGP3665Removing the vinyl strips…

 

 

 

 

IMGP3667Final product.

 

 

 

 

IMGP3669Here the rudder trailing edge is being attached for final trimming to appropriate length.

 

 

 

 

IMGP3671and the whole nine yards clecoed together ready for match drilling.

Rudder Framework

All the steps for 7.4 and 7.5 were completed today, along with 7.6.1 and 7.6.2. This means all the rudder framework parts (spar, horn, ribs, stiffeners) have been drilled, countersunk, and deburred ready for corrosion prep.  It took about 5 hours to get this done.

IMGP3642 The first steps involved countersinking nut plate fastener holes on the Rudder Horn.  This is a crucial part of the airplane steerage mechanism as the rudder control cables will attach here.  Countersinking this side with a micro-stop countersink cage was easy, the backside not so.

 

 

IMGP3643the back part of the horn piece is rounded, meaning the countersink cage cannot be aligned perpendicular to the surface and parallel to the hole.  As a result, hand countersinking was required.

 

 

 

IMGP3646Voila.  Using a hand crank attached to the #30 countersink bit, I was able to get the proper alignment.  It took a while longer to hand-bore out the metal, but actually I liked the control.  The appropriate flush rivet was continually used to check the depth, which in my opinion turned out quite nice.

 

 

 

IMGP3649Next was drill out the lower spar rib and corresponding flange part to match the attachment points to the horn.

 

 

 

 

IMGP3655aThe striker plates were also countersunk by hand.  These will eventually be flush riveted to the lower rudder spar.  They serve as the contact points for the rudder stops prepared in Section 6 for the vertical stabilizer.

 

 

 

IMGP3653Horn, striker plates, lower rib and spar clecoed together after match drilling and deburring.

 

 

 

 

IMGP3658Stiffeners attached to the rudder spar.

 

 

 

 

IMGP3659One rudder skin clecoed in place for stability.  Next steps will be debur the other skin and peel vinyl strips off the exterior surface along the rivet lines.

 

 

Rudder Ribs

Finished separating the ribs parts with associated deburring from steps 7.2.1 and 7.2.2.  Also ordered inital round of attachment hardware for the bonding straps and static wicks to be used on the vertical stabilizer and rudder.

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MISC – Peter helped move the first dunk tank section out to the shed, plus added bracing to work surface legs. The premium buckets which will hold the alodine and brightener chemicals also came in yesterday.  These were relocated out to the shed this afternoon.

VS Metalwork Complete

 

This week all the preparation metal work leading up to alodine processing has been completed. This means corrosion prep, priming, and final assembly with riveting remain, but at least all the fitting, match drilling, deburring, dimpling and countersinking operations are done.  From the build plans Sections 6-1 through 6-4.5 have been signed off.

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VS Skins

The first use of the DRDT-2 dimpling device was on the vertical stabilizer skins. 

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A spare tablesaw base with 2×4″  mounts was adjusted so the height of the C-frame bottom was level with the top of my EAA-1000 workbenches.

 

 

 

IMGP3583Laying  a 5/8inch sheet of MDF on the bench top provides a seamless surface to the DRDT-2.  This picture shows the MDF will support the skin exactly level with the male die for the dimpling operation. 

 

 

 

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This setup allowed us to dimple with the skin resting on the bench top (saved me from building a special platform just for the DRDT-2 for this purpose).  The process went quickly and the results were excellent. When properly setup, the DRDT-2 will produce a uniform dimple every time.

 

 

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Repair Rudder Stops

In Section 6 the rudder stops are supposed to be fitted and match drilled against the upper of the bottom hinge brackets.  I was about to post a picture of this activity when I noticed the lower bracket was showing in the picture.  As a result, I went back today to correct back to the appropriate configuration (upper of the two brackets).

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