RV-12 Rudder Pedal Block Extensions

Thus far, I have been very pleased with flying the DOG Aviation RV-12 … it is truly a nice flying airplane. My only minor complaint stems from the rudder pedal configuration, in that, I find it difficult to make large rudder inputs with my feet on the rudder pedals without also pressing on the brakes unless I keep the balls of my feet pulled back in an unnatural position. Of course, for most ground operations or while in the air, this is not an issue … but on short final or during takeoff roll it requires a cognizant effort to pull the tips of the toes aft to insure large rudder inputs are not accompanied with unwanted brake inputs.

Sliding the feet higher on the rudder pedals would help but then the tips of my shoes (size 12) run into interference with the firewall shelf. Admittedly, it is not a big deal … just a few moments of uncomfortableness while pulling the toes aft to keep them off the brakes during takeoff and landing.

That got me thinking ... Gee, if the F-1290 pedal blocks were a little thicker, it might put my feet in more of a natural position on the rudder pedals and  help keep them off the brakes. With all the buzz about 3D printing, I decided to see if I couldn’t make a set of pedal blocks that are exact copies of the Van’s F-1290 pedal block … just a little thicker so the feet are in more of a natural position when on the rudder pedals. But that posed a problem … I have never used any type of 3D modeling software, so where do I begin?

EAA (Experimental Aircraft Association) to the rescue. I was talking to some friends at the airport about wanting to 3D print a set of thicker rudder pedal blocks, but didn’t have access to 3D software. I was informed that as an EAA member it was possible to obtain a free full featured (minus stress analysis) version of Solidworks Educational Premium that college student’s use. The EAA has formed a partnership with Solidworks allowing EAA members to download Solidworks Educational Premium for free … along with a 1 year license agreement which can be renewed as long as EAA membership is valid.

Knowing nothing about Solidworks (or any other drafting program), it seemed like learning to draw the thicker pedal blocks would be a daunting task. When first launching Solidworks, my eyes immediately glazed over … the sheer number of menus, options and submenu items available is truly daunting for a beginner. Fortunately, within Solidworks (under the help menu) there is a very good built in tutorial that starts out simple and builds on previous lessons.

After playing with the tutorials for a few evenings, I was able to acquire enough knowledge about Solidworks to successfully draft up a thicker rudder pedal block by carefully measuring the F-1290 pedal block and entering those dimensions into Solidworks then adding an extra ½" to the overall height of the petal block. I did not want to change the mounting bolt hardware so a recess was made for the mounting bolt to drop into. With a little bit of tutorial practice and some patience, making an accurate drawing for a thicker pedal block was not that hard. Below are a few screen shots of the finalized design drawing.

Top view of the thicker rudder pedal blocks drawn using Solidworks.

Bottom view of the thicker rudder pedal blocks.

Side view of the thicker rudder pedal blocks.

 End view of the thicker rudder pedal blocks.

A couple of years ago Tom, a friend who is building a RV-10, mentioned he bought a 3D printer and made the offer should I ever want to have something printed, to let him know. I told Tom about my using Solidworks to create a drawing for thicker rudder pedal blocks and he said he had plenty of blue HDPE filament … so Tom printed two blocks for me that are hollow inside with a crosshatch pattern for strength to save on material, since they are just for proof of concept. Thanks Tom!!!

The blue RV-12 rudder pedal block on the left was printed by Tom using the Solidworks file I made.

Side by side one can see the blue pedal block is the same as the black Van’s pedal block on the right … just a ½" thicker.

Bottom view of both rudder pedal blocks. Have to say, as a first time effort at making a 3D drawing and then having a part printed from the drawing, the thicker rudder pedal block looks great.


The big question now is how well will the thicker rudder pedal blocks actually work out? Only one way to find that out … install them.

The thicker proof of concept rudder pedal blocks installed on the pilot side of the DOG Aviation RV-12.

For comparison, these are the original Van’s F-1290 rudder pedal blocks on the passenger side.

So you are probably wondering … was it worth the effort … absolutely! My feet are now in a much more natural position when placed on the rudder pedals. Although the blocks could even be a tad thicker, the positioning of my feet on the rudder pedals is much more comfortable while moving the rudder pedals and staying off the brakes ... so I’m calling this effort a success.

Now that I know the Solidworks drawing I’ve made will produce a functional part, the plan is to make up four rudder pedal blocks from a tougher black material such as NylonX or CarbonX. Unfortunately, Tom’s 3D printer does not have the proper type of printer nozzle required for those filaments, so I will need to have the final pedal blocks printed elsewhere.


Return from the future:


As previously mentioned, the printer nozzle on Tom’s 3D printer is not suitable for printing stronger filament plastics like CarbonX or NylonX … so a few months back, I contacted Steve at rvplasticparts.com who is a fellow RV owner on the Van’s Aircraft Forums (VAF) that has a cottage business of 3D printing accessories for owners of various models of Van’s aircraft. I told Steve I've made a drawing of a taller rudder pedal block and had already printed a prototype which fit nicely. However, I wanted to have a set printed using a stronger material such as CarbonX or NylonX … Steve decided NylonX would be a good choice. I told Steve he could have my drawing to use if he wanted to add the thicker rudder pedal blocks to his product line and he decided to take on the project.


Steve tweaked my drawing a tad and will be offering the taller rudder pedal blocks in an assortment of thicknesses. The prototype Steve sent me is 3/16" taller than my original prototype … which should be perfect since my prototype blocks felt good … but, as mentioned earlier in this post, could stand to be a little thicker. Another change Steve made was increasing the thickness of material under the bolt head from ½" to ¾" feeling the end result will be much stronger. The original rudder block from Van’s was ½" so I made my drawing using the same thickness which created a surprise when I tried to test fit the new taller NylonX rudder pedal blocks Steve sent me …. the original AN4-15A bolts were not long enough, so I needed to order longer AN4-17A bolts. Below is a photo showing the new NylonX rudder pedal block on the right, my proof of concept prototype in the center and Van’s stock rudder pedal block on the left.

As can be seen in this photo, the NylonX rudder pedal block on the right is 3/16" taller than my original blue prototype in the center which is 1/2"taller than the stock Van's rudder pedal block on the left.


As previously mentioned, my blue prototype shown above felt good and is a vast improvement over the stock Van’s rudder pedal block … but I felt the block could stand to be even a tad taller. When the longer AN4-17A bolts arrived today, I headed to the hangar to test the fit of the new NylonX rudder pedal blocks Steve printed for me. At first, I only replaced one block so I could compare the feel of my prototype with Steve’s 3/16" taller rudder pedal blocks. The overall feel was about the same … but I noticed Steve’s NylonX rudder blocks allowed larger rudder inputs before the foot actually began pressing on the brake pedal. So overall, I’m very happy with the thicker NylonX rudder pedal blocks Steve printed and will order another set for the right side of the airplane.

The new taller NylonX rudder pedal blocks installed. Note to fellow RV-12 owners, changing to these rudder pedal blocks will require longer AN4-17A bolts to replace the AN4-15A used to install the stock Van’s rudder pedal blocks.


A big thanks to Steve at rvplasticparts.com  for taking on my project and sending me a prototype to test. I think this is one modification other RV-12 owners will want to look into … especially if keeping your foot off the brake during rudder inputs feels slightly uncomfortable for your foot.


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The photos below are just stored here so I can post them on the forums. Basically, kicking around an idea here. Background: The owner of a RV-12 has a grade in front of his hangar to traverse and is trying to figure out a good way to get his airplane into the hangar without holding onto the tow bar so he can hold a winch controller or pull a rope connected to pulleys.

I suggested reversing the tow bar and pull it with a winch or rope/pulley setup connected to the reversed tow bar. However, it was pointed that without locking the nose wheel somehow, should the tail begin to track off center a little, the castering nose wheel will make matters worse and quickly get the airplane off track … true enough.

So that’s had me thinking for a few days and I think I’ve come up with an idea that may solve the guy’s problem. During the last unexpected warm day we had here I slipped up to the airport to take a few photos I will post on the forums. The idea is to use the RV-12’s steps to support a board traversing the bottom of the fuselage that the tow bar can rest on and be secured between blocks. The blocks will prevent the tow bar from moving side to side thus keeping the nose wheel locked straight while the tow bar is being hauled aft into the hangar by a winch or rope/pulley arrangement. Below are proof of concept mockup photos using a yard stick so the RV-12 owner can see my vision in a picture form.

The tow bar is placed on the nose wheel reversed as shown here and will sit on horizontal piece of wood or metal traversing the belly of the airplane. The areas where the blue tape is placed around the tow bar will need blocks attached to the horizontal piece to capture the tow bar. The blocks will capture the tow bar preventing side to side movement thus keeping the nose wheel held straight as the airplane is pulled backwards into the hangar.

The horizontal piece needs to be connected to the RV-12’s steps using a vertical piece that has wooden pins which will insert snugly into the step’s tubing as shown in this photo … or the vertical piece could slide over the step’s tubing, builders choice. The vertical piece will likely need some gussets where it meets the horizontal piece to stiffen the assembly, so the fixture has no side to side play. The steps will lock the whole structure preventing ant side to side movement and also support the tow bar as the airplane is pulled aft into the hangar.

As can be seen in this photo, the Van’s tow bar ends well forward of the com antenna.

Looking aft, As can almost be seen in this photo (bad focus), the com antenna is biased to the pilot side of the RV-12’s bottom fuselage … so a cable or rope connected to the center of the tow bar handle will easily pass by the com antenna.


I  believe my idea will likely work well, however not having an incline to traverse to get inside my hangar, won’t be constructing a working version to prove the idea actually works.

DOG Aviation RV-12 Receives Two Accent Trim Colors - Completing The Paint Job

As mentioned in the previous post, Jeff at Custom Aviation was given a picture of the desired paint scheme for the DOG Aviation RV-12. The paint scheme picture was made using a photo of a mostly white RV-12 found on the Internet which was edited using a photo editing program to create the paint scheme design. I feel Jeff did a terrific job of interpreting my picture and masking the RV-12 accordingly for the accent trim colors. I told Jeff that the edited picture was just an overall concept and that he had free reign to do what he felt would work out the best and look good based on his experience …  the end result closely matches my design.


I desired taking some photos of the masking process … so when Jeff finished masking one side of the RV-12, I made the drive to the paint shop with a trailer to retrieve the wing cradle (thanks Mike for towing your trailer up there and back) and while there, took a few photos of the masking tape applied onto the RV-12's fresh off-white base color.

Jeff at Custom Aviation has completed masking the left side of the RV-12’s fuselage for the accent trim colors.

The wing tips will also receive a little trim accent … the tips were masked accordingly so the main trim color will extend to just inboard of the landing lights.

Left main gear wheel pant masked for the accent trim colors.

The stabilator will also be receiving accent trim colors along the outboard tips.

A couple of days later, Jeff called and said the painting was completed and I could finish up attaching the rudder, tail cone fairing, landing light lenses and the inspection port covers … thus completing the reassembly of the RV-12. I’m pleased with the transformation from an unpainted, unfinished looking airplane to a stylish, freshly painted airplane that looks ready for travel. Below are photos of the before and after.

The DOG Aviation RV-12 about to enter Custom Aviation’s paint shop at Portage County airport.

The DOG Aviation RV-12 after being painted by Custom Aviation at Portage County airport.

A keen eye may notice that the fuel cap just aft of the rear window is not painted. I elected not to paint the fuel cap because over time they always seem to become chipped. The plan is to either try polishing the fuel cap or perhaps look into having it chrome plated.


As one can see in the above photos, the colors chosen for the Dog Aviation RV-12 are a little out of the ordinary, in that, quite a few airplanes are typically painted red, white or blue and/or combinations thereof. Wanting to be a little different, purple and green were chosen as the trim accent colors. These colors will match nicely with the green RV-12 stitching on the seat backs and baggage bulkhead cover along with the deep purple powder coating used on the instrument panel, flap handle and steps. I would have preferred a little darker royal purple …but here again, did not want to dive into custom mixed paints. So chose a purple that, although not quite as deep as I would have preferred, still looks good.

The top and bottom of the outboard portion of the wings received accent trim paint extending to just inboard of the landing lights.

The outboard portion of the stabilator received the same accent trim colors and scheme as the outboard portions of the wings. The new stabilator tip fairing is not installed in this photo, but it is painted purple as well.


The decision was made not to install the stabilator tips, wheel pants and gear leg fairings while the RV-12 was at the paint shop for a couple of reasons. Mainly, I want to get an accurate measurement of just how much weight the paint alone added to the RV-12. Plus, the RV-12 has never flown with the wheel pants, gear leg fairings and stabilator tip fairings installed, so I did not want to add any unknown variables during the initial flight home after paint. Fortunately, the RV-12 flew the same way on the way home as it did on the way up to the paint shop.

The freshly painted DOG Aviation RV-12 arrives back home to hangar 45.

Now that the RV-12 is back at the DOG Aviation hangar, the next step is to drain the fuel tank and remove everything except the items that are required to be in the aircraft at all times so the new weight and balance calculations can be made. After that is completed, the stabilator tip fairing, wheel pants and gear leg fairings will be added and another weight & balance measurement made. That way I will know how much weight the paint alone added along with the new balance numbers … plus, will also know just how much the numbers change when the wheel pants, gear leg fairings and stabilator tip fairings are added.


Return from the future. Rather than start a new post decided to just add a photo of the completed DOG Aviation RV-12 with the stabilator tip fairings, wheel pants, main gear leg and intersection fairings installed.

The DOG Aviation RV-12’s final configuration ready for traveling. The stabilator tip fairings, wheel pants, main gear leg and intersection fairings are all installed.

DOG Aviation RV-12 Receives Off-White Base Color

The base paint color chosen for the DOG Aviation RV-12 is an off-white (not quite as dark as I would have preferred). When looking at color chips for a creamish off-white that leans towards brown, I found an off-white that was a tad lighter than what I wanted and the next darker paint chip seemed too dark for my liking so I went with the lighter off-white. Not wanting to step into the world of custom mixed paint, decided to just go with the lighter off-white color. Sure, could have opted for a custom mix … however, should a touchup be required in the future, hopefully having chosen a standard color from the color chart will result in a closer match. Interestingly, when looking at the paint for the first time after it was sprayed, it seemed really white to me … however, when compared to a bright white airplane just painted at the shop with Matterhorn white paint, it is truly a darker creamish off-white color.

Painted canopy sitting on the wooden canopy frame I made specifically for this purpose (mentioned in the previous post). The wooden frame keeps the thin edges of the canopy skirts that protrude below the canopy frame off the saw horses … this prevents the skirts from becoming bent and scraping paint off the fuselage where the canopy overlaps.

Fuselage and stabilator ready for reassembly.

Side view of the fuselage from the front.

Painted right wing, flaperons, rudder and anti-servo tabs. Jeff the painter taking a well-deserved coffee break.

The fiberglass parts …. wheel pants, intersection fairings, tail cone fairing and gear leg fairings.

Jeff wanted me to begin assembly of the tail section so it could be masked off for the accent trim colors while on the airplane. This will involve reinstalling the vertical stabilizer and horizontal stabilator along with temporarily pinning the rudder in place. The rudder will receive the accent colors while off the airplane. The wings will also be attached so masking can be applied to the fuselage and the wing tips for the trim colors.

Tail section and canopy reattached and cowlings installed.

Note to fellow RV-12 builders: Those that have completed the service bulletin for the bearing bracket on the stabilator will discover that attaching the stabilator onto the tail cone is a tougher challenge now. A few suggestions … grind down two AN4-12A bolts to remove the threads and put a small taper on them so they can be used as “pins”. Raise the nose wheel and place it into one of the holes in a standard concrete block. Tape really thin foam wrap sheets onto the side of the fuselage to prevent scratches. Place the stabilator onto the 25” saw horses you made to prop up the fuselage … the alignment will be close enough to work with. Have two helpers hold each end of the stabilator and insert the counter weight into the fuselage and slide the stabilator forward so the counterweight arm bolts can be installed. Carefully move the stabilator forward and in position. Forget about installing the washers on either side of the bearings and just temporarily use the tapered bolts to “pin” the stabilator in place. At this point, only one person needs to hold the stabilator in position as each “pin” is removed one at a time and replaced with the AN4-12A bolt and the required washers. I would suggest wearing a miner’s light (preferably one with an incandescent bulb to reduce glare) and use a comfortable creeper … you will be on your back for quite a while. If you don’t have a washer holding tool, use painters tape to tape each washer onto a thin metal ruler and slide the washer in place and slip the bolt through it. It sounds easy … but it is not … IT IS an exercise in patience … lots and lots of patience. Frankly, I think this is one of the toughest tasks to perform on the RV-12 … it is amazing how difficult inserting two bolts through two bearings and four washers can be. I also found using a small piece of vinyl tubing with a wire tie wrapped around the bolt and back through the tubing made for a very easy way to hold the bolts for initial insertion into the holes in the bearing brackets. I've installed the stabilator three times now and although it has become somewhat easier to do, it is not a task that can be done quickly … at least not for me.

Two AN4-12 bolts that have had the threads ground off and a slight taper placed on them so they can be used as “pins” to quickly get the stabilator in position without worrying about the washers on either side of the bearing. Once the stabilator in position, the “pins” are pulled one at a time and replaced with a threaded AN4-12 bolt and the appropriate washers. The vinyl tubing and wire tie shown makes a great tool for holding the bolts for insertion into the bearing bracket assembly since there is really not much room for a hand.


After the tail section was installed, work began preparing the wings for installation. The wings were placed in the wing cradle and the flaperons were attached to each wing.

Freshly painted wings attached to the fuselage.

 In the past, I’ve used a couple of pieces of metal bent into a" V" and taped  them onto the outer edge of the wing and flaperon with duct tape to secure the flaperons from moving while the wings are off the airplane. Not long ago I read a post on the forums where a guy suggested using a welding rod inserted through the very aft edge of the wing and slid into the aft portion of the flaperon to capture it. This worked really well … and I can wholeheartedly recommend using this method to secure the flaperons during wing removal/instillation.

Two welding rods with 90° bends on at the ends makes it easy to lock the flaperons for wing instillation/removal.

As can be seen in this photo, the aft edge of the outboard portion of the wing has a gap just large enough to insert a welding rod.

The gap along the aft edge of the flaperon aligns with the gap along the aft edge of the RV-12’s wing.

Looking closely one can see the welding rod in the gap between the inboard edge of the wing and outboard edge of the flaperon. The welding rod captures the flaperon securing it in the neutral position. Using the welding rod to “pin” the flaperon means the flaperon no longer needs to be held during wing instillation or removal.

The next step involves Jeff interpreting a picture made of my desired color scheme which I overlaid onto a photo of a RV-12 using a photo editing program. Jeff will use the edited picture as a reference for applying the masking for the trim colors and N numbers. When the masking is completed, the two trim colors will be applied to the DOG Aviation RV-12.