Stabilizing success

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I skipped a major step during the tailcone build sequence by never installing the horizontal and vertical stabilizers onto the tail cone. I didn’t see a point of doing that in the garage just to take it all apart again for storage for years. Now that I’m in the hangar and have the room, no excuses are left. I didn’t build either stabilizer, as the original tail kit owner built them. After looking over them and cleaning them up, I “touched up” a few of the rivets I felt were under squeezed. They aren’t primed on the inside either but even after 10 years of sitting around, they are looking good and corrosion free.

The process went as planned and I spent the better part of one full day getting it all drilled and bolted on. I had purchased the CNC brackets from somewhere to mount the horizontal stab so I didn’t have to make them. I have no clue where I got them from, however, as I bought them on a whim years ago. Either way, they’re nice and you should buy them.

The only hiccup came when working on the elevator trim cable. The original builder had installed the plastic snap bushings the trim cables run through while building the stab. Unfortunately, he put the wrong size bushing in one of the holes that was buried in the spar. The cable wouldn’t pass through. Fortunately the hole was the correct size but man was it a pain in the ass and fingers getting that old one out of there.

Laura helped me bolt the rudder on next to set the rudder cables up and do some trimming for the rudder trim wires and tail light wires. All easy stuff and its really exciting to see the tail feathers finally get attached.

I was able to finally hook up the elevator torque tube after drilling the horns. I was careful to get them lined up accurately and am pretty happy with the end result with the right elevator being lower on the trailing edge by about 1/16″.

I then set out to start the rigging process by centering the stick and adjusting pushrods to get the control surfaces all lined up. It takes quite a bit of stick movement to get the control range established by the plans and I found some interference with a bolt on the aileron rods under the seat pans. I was able to switch the bolt orientation and it cleared right up.

The autopilot roll servo went into the right wing pretty easily as well. I had the mount installed during wing construction, so it was a matter of bolting it in and attaching it to the aileron bell crank. The wiring hooked up quickly since I had already ran the wires and installed a connector.

I cleaned up a bit of the wing root area as well, hooking up the CPC connectors, pitot/AOA tubing, and ensured it all cleared the control rods inside. I had planned to mount a bracket holding the CPC and pitot/AOA tubing somehow, but the whole bundle is so stiff, I’m not too concerned with securing it further. It’s also well clear of the torque tube despite the appearance in the picture.

Finally, we had some good light from the sun on the propeller and I couldn’t help but drool over it for a few minutes. The orange over black with the polished leading edges are just too damn cool looking. The scimitar shape is sexy too!

Legal Disclaimer

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I’ve realized a good amount of pictures were not appearing correctly on some posts, especially those over the past year. I’m not web specialist so I think I finally have them all fixed. If you see some that are still rotated 90*, please let me know.

I also realized how horrific my spelling is. I typically vomit all these blogs to myself in an email and realized that the spell check function isn’t working before I post them through WordPress. So I have this false sense of confidence that everything is perfect.

Please excuse my grammatical short comings and focus on the awesome sideways pictures!

Throwing gas on a fire

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I’m getting bad at taking progress photos, as quite honestly I’m under the gun on getting this thing airworthy and ready for inspection by November 12th.  So I’m really powering through a lot of tasks and am so exhausted by the end of the night I just forget to document it all.

We got the wings back on and permanently bolted on.  I had to order a few washers as the nuts bottomed out on the threaded portion before they should have.  I just added one washer on each bolt and got the proper torque value with no spinning in the hole.  I did the same with the main landing gear bolts on advice from another builder who had a bugger of a time replacing the bolts after the holes elongated.

Fuel testing is next on the list and a big hurdle to climb over.  We had pressure tested the tanks, but I was still a bit nervous to put avgas in them for the first time.  I collected all the gas cans I could muster and had enough to hold 36 gallons for the first fuel tank test.  I also bough two two-gallon cans to calibrate the fuel senders.  This test is not only for the tanks, it will see if I have leaks in the lines and will finally show what fuel flow the pumps provide, a key test point for first engine start and flight.

We started by filling the left tank at two gallon intervals and capturing the value on the avionics to create the level points.  The cans nor the amount in them were exactly precise, but it was close enough.  Parish and Jacquie came over and helped us with the reward of eating pizza on the ramp after filling the tanks.

We did 30 gallons in the left and then removed the sump drain to empty the tank and prepare for calibrating the right tank.  The right went pretty easy and we had no leaks on either tank!  I was nervous about leaks but the tanks held great.  Parish and I worked out a good technique of draining the fuel and switching gas cans.  Much easier with two people!

After the right tank was calibrated, I removed the return line from the firewall and put in an empty can to get ready for the flow and pressure test.  It took a few long seconds for the pump to purge air and draw fuel, but after what seemed like eternity, the noise changed and the pump got a hold of liquid.  Unfortunately, that liquid came spewing out of the firewall instead of the hose!  Turns out I mixed the fuel supply line and return line on the tunnel side of the firewall.  That caused a big oh shit moment!

A bit of head scratching and cussing lead to digging in the already disassembled tunnel even more to get at the firewall.  Folks, not an easy task.  Two extensions, crowsfoot, and a lot of scratches, but I was able to get the lines un-crossed and hooked up on the tunnel side correctly.  

We flipped the fuel pump on again and had fuel coming out of the correct line.  We also had fuel coming out of the filter fittings.  Yup.  So, back in the tunnel I go.  Like an idiot, I didn’t use fuel lube (EZ Turn) on the AN NPT fittings into the fuel pumps.  I did for the fuel pumps manifold, but not the filters.  Gah, idiot.  So I had to take the whole fuel pump/filter module out and get at it on the bench.  While it’s not impossible, it’s not easy.  I’m definitely putting another tunnel access panel on the copilot’s side during the first annual.

Fittings were properly lubed and torqued, so the module went back in and we turned the pump on for a third try.  That was the ticket, as we got good pressure readings and good flow.  I turned the pressure up a bit to 45 PSI on the regulator and we did flow tests equaling 45 GPH on a single pump and 75 GPH with both on.  Plenty of fuel to feed the thirsty engine on take off!

Tess had one more surprise for me, though, when I attached the return line back to the firewall and found one more leak, this time at the outlet of the pressure regulator.  Seems that I didn’t torque that line at all.  Oops.  Again, this is why you extensively ground test!  Got that one all fixed and ran the pumps for about 30 minutes, just recirculating fuel with no issues.  She’s ready for engine start!

Back to my roots

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The wings are initially fitted to get the wing root covers installed and hook up fuel lines, vent lines, while getting the flight controls initially rigged.  The wing root cover brackets went on quickly and I fabricated the two fuel vent lines that exit the bottom of the wing root cover.

You also drill the bolt hole in the rear spar and work out a few other fasteners.  I installed the flight controls and worked out the stick to the plans while adjusting the rigging and pushrods.  It wasn’t too bad of a process with a little patience and double thinking before adjusting a rod end the wrong way!  In an afternoon, I had all the controls lined up nicely with the wingtips and fuselage just as described in the plans.

I also finished up the fluid lines up front.  TS Flightlines really came through again on an awesome product.  I had one line that didn’t quite fit to standards and the return lines for the fuel tanks from the tunnel had the wrong fitting (my fault) on them, so those went back for modification.  If you don’t know, TS will rebuild the lines for free until they are correct.  You get what you pay for and I’m glad I spent the money knowing I’ll have lifetime quality hoses.

On a side note, my engraved parts came back looking fan freaking tastic.  The door handles are an extra set that I had and will go on after paint.  The data plate turned out perfect, as did the fuel caps..

Speaking of fuel, a while back I misdrilled the holes in the tunnel on the right side for the fuel line.  I decided at that time to just use a 90* elbow but that made torquing and replacing the incorrect fuel line difficult to say the least.  So I broke down and ordered 90* bulkhead fittings to do it correctly.  I had to dig into the tunnel to put the proper spacers (covering up the now too large hole) and secure the lines from the fitting to the fuel valve.  Boy am I glad I did this, because while looking around since I was in there, I discovered a cross threaded line on the fuel valve that would have made a mess come testing time.  I was able to clean the threads on the fitting and got it on correctly.  I took my time to reinspect all other fittings and lines.

With the airworthiness inspection scheduled for early November, I am shifting into inspection mode so try to check everything I can while working in an area.  It just so happens that the 137 articles Vic Syracuse has written for KitPlanes all mention loose jam nuts!  I want to break that chain but came close to being a statistic in your next bathroom reading material.  The left aileron jam nut had just enough space that it caught my eye while working the fuel lines.  Ha!  Not today, Vic, not today!

Another little side job that had been lingering was wrapping the aircon line with insulated tape to ensure the thermostat coil was in good contact with the line.  I had ordered this sticky tape months ago and finally crawled into the baggage area to finish that up.

Finally, Laura came over to help me pull the wings off so we could prep and install the wing root brackets and finish up the few tasks before permanent install.  This coming weekend will be critical for staying on track towards inspection, as I need to get the entire tail surface wrapped up and the fairings done.  Fingers crossed!

I give you wings, Red Bull gives you diabetes

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Before the wings go on, I finished up a few odd jobs since the parts came in from various suppliers.  I ordered enough hose to route from the air oil separator to the cowl exit and secured it in place.

I also finished securing the air con hoses from the firewall to the compressor.  I made a bracket to hold hose clamps on the bottom of the valve cover and it keeps the hoses from flopping around the side of the engine.

I also did something on the right side of the engine.  I don’t know what I did, but I took this picture which meant I did something over there.  I know I secured a few wires, added a ground from the engine to the mount (which I may have mentioned before, I don’t know), or maybe I just felt it looked pretty.  Either way, here’s the right side of the engine and the mass of wires; enjoy.

Tapping into my network of gulible aviators, I ropped two guys into helping me install the wings for the initial fit.  I must admit, I typically don’t read ahead more than a few steps in the plans so I was pretty dissapointed to find out the wings go on then have to come back off before getting bolted on for good.  It figures, though, you wind up doing everything twice on this airplane so why would the wings be any different?  We got a few sawhorses and a plan together and according to the time lapse video shown below, we installed the wings in about 27 seconds!

Really, they went on a lot easier and smoother than I expected.  I ordered new nuts for the wing attach bolts but will reuse the original bolts used during construction of the fuselage.  I did get the suggested hardware store bolts to align the wings initially and they worked very well.  I also felt better seeing the good fit between spar components, as I had a scary moment a few years ago when I realized my spacers weren’t the proper combination even though the dimensions worked out in the end.  Either way, everything fit snug and as it should, so all is good.  Great job Steve, smile for the camera.  Or not.

It’s pretty bad ass to see wings on the plane after 6 years of telling everyone you’re building a plane but it actually looks like an enclosed canoe.  So I decided to have a bit of fun and hook up the ZipTip lights.  Combined with the gull door lights, it looks like a space ship!

The evening was getting late, but the big triangle box was too tempting for me so I pressed on with hanging the prop.  Following the manual, I inspected and oiled the critical o-ring on the hub and ensured no damage as it slid on the prop flange.  Again the engine hoist came in handy as I secured the prop to the hoist and used it to lift in place without asking for a third back surgery.

The bolts for the propeller are rediculously stupid and hard to get to.  Once I got each one threaded, a challenge in itself, they can each be turned about one revolution at a time before all the others have to be tightened in sequence.  There just isn’t much room and you want the prop to go on evenly.  An hour later, I had the bolts hand tight and the prop was on.

I realized quickly by my goose bumps and those on the propeller blades that it was chilly, so I went and got some socks for her.  David makes these as a business (search BladeSox on Facebook) and they are just the bee’s knees.  I don’t care if they make me a super dork.  I had him do the tail number, Van’s new logo, and the best – our RV10 logo created by Sam at Plane Schemers.

It’s really starting to look like a plane now!

Wipe the cowl off your face, we’re moving!

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Thanks to a great guy on base that has a side business of welding, I had my AFR (O2) sensor bung welded on the exhaust per Ross’s recommendation on location.  I chose the #6 cylinder, but he said it doesn’t really matter.  I chose that one since it fit well there.  The sensor has a controller that I attached to the engine mount just above the battery box.

I never have been able to wrap my head around the nose gear fairing made by Show Planes until I physically put it all together.  The idea is to not only support the lower cowl around the exhaust openings (and air exit) but also smooth the exiting air flow around a turbulent area.  I started by attaching the front and rear fairing together and then positioning it roughly on the lower cowl.

The rear piece has a few lips that fit over the bottom skin to help locate it correctly, so I did an initial fit before starting to trim the nose gear slot.  Bryan shows a very tight opening for the gear leg, but I’m not sure how much it actually moves, especially on a grass or dirt strip, so I’ll leave a bit more room.

Once initially trimmed, I drilled into the bottom fuse and used nut inserts vs. sheet metal screws.  I figured it’d give a better grip long term and less chance of stripping holes.  Once the fairing is on, it reminds me of a duck billed platypus.  Ha!

I chose to use more SkyBolts to secure the fairings to the cowl.  I am also following Joe Keys’s lead on making a cover plate to cover an extended nose gear leg slot.  This will allow the cowl to fit a bit better going on and coming off since I have the dreaded three blade propeller.

I finished up by extending the cowl slot as far as possible while still covered by the fairing and epoxied the front fairing onto the bottom of the lower cowl.  Getting the lower cowl on and off is a bit of a challenge, but it does just fit and the blade sox I have really pay off here to avoid nasty scratches on the prop blades.  

Since the cowling was the last big project left to complete at home, the fuselage is ready to join the wings at the airport!  I was able to complete all of the interior, electrical, avionics, and engine including cowling at home which saved a lot of time and money in the long run.  Now I need to fit the wings and tail surfaces to finish up the build and need the hangar space to do so.

On a sunny afternoon, we rolled the fuselage out and did a good blow job (hahahaha, grow up) to get most of the dust off of everything.  I found a roll back wrecker driver that made me feel comfortable and who wasn’t in a hurry to move it the few miles to the airport.  He did a fantastic job, talking through each step and making sure I was happy with how we winched it and tied it down.  He took his time on the curvy bumpy back roads after managing down our driveway of doom and destruction with ease.  I think I breathed twice during the 45 minutes it took to move it and I only panicked once when I thought tree limbs were going to scratch the windscreen but were actually three feet clear.

We rolled it off the wrecker onto the ramp and quickly had it tucked away in her forever home at IPJ.  Laura helped me roll the wings still in the wing rack down from the other end of the field (a 20 minute walk with those puppies).  Two guys who I know flying the Diamond were kind enough to let me store the wings for almost a year in their hangar free of charge.  Truly great people makes things like this happen, can’t say enough.

About five trips later, we had all of the tools, parts, pieces, dust, and components all in the hangar.  For the first time, everything is together in one space that will be a flying airplane very shortly!

Insert witty title here – baffles, oil door, random stuff

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The baffles are all trimmed up and ready for a coat of high temp engine paint.  Looking back, I wish I had them powdercoated, but too late now.  They’ll get scratched up and at least this way I can touch them up, similiar to my mentality for the interior.  The front ramp area was trimmed significantly for the air conditioning compressor and turned out pretty nice.  I removed the front fence on both sides, as others say there is no point in them.  I can always add a bit of tape later to warm CHTs up if needed.

The rods that hold the bottom of the baffles together were a bit of work, as you have to put some bends in the rods and then thread them.  I’m using these as mounts for the sensor wires as well as a few other wires including the starter wire and alternator b lead wire.  It really cleans up the wiring nicely and keeps everything tucked away.

With each connection at the engine, I get to verify functionality by turning on the avionics and looking for realistic numbers.  For instance, I now have 14 different temp sensors all telling me the garage is in the low 70’s!

I fabricated up a bracket to mount the throttle cable to for the throttle body.  It routes under the bottom of the engine and since it’s not exactly a stock setup, there is not stock cable mount.  It was a pretty simple fix with some angle channel and a few bolts.  I am thankful I ordered a lot of various 1/4-20 bolts for the engine case since they are not standard AN bolt threads.  The throttle cable is now attached and rigged with good travel on the throttle body and throttle lever, so I’m 50% complete with engine control cables.

The prop lever didn’t work out so quickly or successfully.  After I mounted the Show Planes bracket and hooked up the cable, I began to wonder why the governor is sprung to low rpm/high pitch.  Yeah, oops, no, that’s not right.  The governor can be configured a few different ways including rotational actuation and mine is backwards.  I called Whirl Wind and as always, they took great care of me.  I sent the governor into them and they shipped it back corrected the same day they received it.  Now it is sprung to high rpm/low pitch as it should be with proper activation with the cable.

In an effort to reduce the crap on my workbench, I decided to wire the spark plugs and coils to get rid of two big bags taking up room.  I ended up re-configuring the mount for the coil connections on the top case mounted coil and it made running the signal wires cleaner and easier.  The plug wires themselves were pretty easy and quick to run now that I have the MSD crimp tool.  The biggest challenge was deciding how to route and secure the wires.  I’m pretty happy with some Amazon plug wire organizers and a few adel clamps.

Since everything inside the baffle area and the baffles now on for good (thank goodnes, they are a pain to get on and off a bunch), I could test fit the plenum, ducts, and cowling for the first time.  Boom, it all fits!!!  The plenum is just clear and will allow a bit of shake room for the engine within the cowl.  The intakes and cooling ducts clear the inlets by about 3/8″ and I test fitted the bulb seal which I think will work nicely.  Everything lines up nicely and I think it’s going to work out to a clean and effective installation.

I will need to check the oil from time to time (it’s a joke folks) so the oil door needs to be fabricated.  I have the hidden hinge from Cleveland Tool and planned on using Cessna push button releases for the fasteners but decided against them once I got them in hand.  I just don’t like how they work or look.  I want it convenient to pop that door open and thus will sacrifice looks a bit for functionality.  I ended up ordering the winged Skybolts.  The releif area was cut out using the cutting wheel and I realized that I didn’t leave enough of a flange to mount those Skybolts.  I test fitted the top cowl with the plenum on and ensured there was plenty of clearance for access to the dipstick and then fiberglassed on more of the flange to correct the issue.

The door itself is a perfect mold and only required a bit of sanding.  The stiffner was epoxied on with West epoxy and a bit of flox to add rigidity.  Once it cured, man it is super stiff!  I let it cure on the cowl with clecos to get good form.  Installing the hinge was pretty simple, just a bit of adjustment to get the hinge point located properly and the spring will allow the door to stay open easing access to the dipstick.  I’ll lay up a funnel shape to enclose the dipstick tube and seal the opening in the plenum in a bit.

Finally, I knocked out a nagging job with the air conditioner.  The condensate drain wasn’t routed to the exterior since I redid the ducts in the tail so I had to come up with a way to allow that water to drain out.  I experimented with a fuel tank bung that I had surplus and a short piece of tubing.  It equaled a great fitting vinyl tube with aluminum tube insert threaded into the bung and riveted to the bottom tail skin.  I put an angle cut on it to help create a low pressure on the tub which will help suck the fluid into the airstream.  Elegant solution, if you ask me.  I know, I’m incredible aren’t I?  So humble too.

I really foamed that up

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Now the cowling is fit, some tricky bits come up on the to-do list including the engine intake ducts and cooling ducts.  All of these are complicated by my air conditioning and plenum choices.  If I get it right, it’ll be magic and a work of art.  I probably won’t get it right the first time, as some of you may have guessed.  I started with getting the engine intakes started.  These start at the cowling openings and form the bottom 1/4 of the opening.  they curve inward and join a Y that holds two K&N air filters before hitting the throttle body.  The ducts are well molded and nice light but strong fiberglass.  The problem is they don’t fit very well with the exhaust and other accessories on the engine.  The Show Planes instructions leave a lot to be desired, but once you piece the components together, it starts to make sense.

I first had to cut a relieve for the alternator.  Not sure if it’s just the Plane Power or if all alternators will require this, but mine was about a 1/2″ too low impacting the right duct.  Next, I had to trim quite a bit for the exhaust coming from #2 cylinder.  I tried to get a good 1/2″ to 3/4″ clearance and will using some heat shielding to protect it from the close proximity.  

On the left side, the air conditioning compressor dictates a much larger modification.  Gaylon wound up elimintating this duct all together but I want to at least try to keep it.  The problem is the compressor blocks some of the cowling opening and thus reduces not only intake air flow but cooling air flow.  I’m hoping since I have a plenum and will have the cooling intake completely sealed, that the minimum reduction won’t interfere with adequate cooling.  Time and testing will tell.  I also want to keep the left side induction to maximize manifold pressure thus power and performance of the engine as well as keep the redundant induction air supply (think alternate air on the stock setup).  

I had to notch out a few spots to create clearance around the compressor and mounting bracket.  Once I had the areas trimmed away and fit properly, I laid up fiberglass by hand to enclose the reliefs.  I debated on creating a mold or plug type thing but determined it’d be next to impossible for me since I’m not good at it anyway.  Plus I tried one of them and was pretty happy with the results, so why make it more complicated?  I did two layers of glass then a third on the inside.  I honestly don’t know what weight it was, but it’s very thin thus the three layers added up to about the same thickness as Show Planes had with the same rigidity.

A bit of sanding and trimming, and everything with the ducts were finished up.  I painted them black just to hide them inside the cowling a bit and because I wanted to.  The last two sensors to install for the engine are intake temperature sensors that I had mocked up and ran wire to but not yet permenantly installed.  I bolted those on and sealed them with RTV to avoid air pressure loss.  I also drilled the required water drain holes just below the air filters at the lowest part of the intakes.

It all sounds so simple now, but trust me, I spent many hours thinking, debating, looking, thinking some more, and finally working out the fit of the ducts and getting a solution that I am happy with.  These were just a warm up for the cooling ducts!  Show Planes have you modify the stock baffle ramps and provide upper cowling ramps to be epoxied to the cowl to help guide airflow into the engine baffles.  Since I am using the plenum, I need to keep air going from the openings to under the plenum.  I had originally invisioned carving foam and creating a mold, but once I got busy working, carving foam was going to be next to rediculously impossible.  It’d take me weeks just to do the molds.  So, I took another approach, use what I had on hand and don’t reinvent the wheel.

The upper ramps from Show Planes are the same size as the openings, so I started with those as a transition to the plenum.  Part of the kit is some thin flatstock fiberglass that I wound up using to create the cooling ducts.  I used some manilla folders to create templates and basically pieced it all together using the fiberglass and super glue.  Starting on the right side was simple, as there is no modifications needed and it’s a much simpler routing for air to enter the plenum covered area.

Again, I figured I’d use this rough build up as a mold to create a sleek curvy, sexy, duct that would look like it came from a Formula 1 team.  So I got a brilliant idea of filling it with blocks of foam and then using spray foam out of a can to fill in the gaps.  I’d then sand, trim, and shape before using it as a mold.  Well guess how that worked?  Not great, folks.  Not great.  I didn’t realize that spray foam has to be exposed to air to set up.  So me putting the duct in a plastic bag in a box resulted not in a nice firm square, but a grocery bag full of gooy sticky snot.

I then decided I’m making it difficult and should just keep it simple, stupid.  So I decided to stick with the original prototypes and just reinforce the joints and smoth as much as possible.  While I waited for the disaster to finish curing so I could clean all the foam back off, I started on the left duct.  This was much more complicated with the compressor in the way.  Not only do I need to get around the compressor, but also the tensioning arm and v-belt.  Finally, the prop governor is there too and oh, wait, I forgot, the refrigerant line from the compressor.  Again, I used manilla folders cut up as templates and just pieced it all together, maximizing the amount of space and using the upper ramp from Show Planes as the starting point.

The end result is not too shabby, even if it’s not beautiful.  I hope it’s functional.  I finished cleaning the foam and set about reinforcing all of the joints with glass tape left over from tip fairings.  Once cured, I did a final fit and trim to provide about 3/8″ clearance from the cowl openings and evened them up with the induction ducts below.  This clearance allows the engine to vibrate and twist a bit within the cowl without cracking the ducts, as you don’t want the two rigidly attached to each other.  I really debated on how to close that gap, thinking about creating flexible ducts from the start or taking what I have at this point and using a rubber strip to seal it.  In the end, I copied an idea from the DA-40 I fly and ordered some bulb seal from McMaster Carr.  I’m hoping this will keep the air from leaking around the duct but allow the engine to move within the cowling.  Again, some testing during first few flights will tell.

I may go back and cosmetically clean these ducts up before paint just to make them look good, but for now, I shot a coat of black paint on them to mask imperfections.  I still need to fabricate up a small ramp that will cover the exposed face of the compressor and help direct smooth air into the ducts.  If I find high temps on 1 3 5 clyinders during flight tests, I’ll copy Gaylon and pull the left induction intake to open that entire side to cooling.  I’ll be honest, this has really weighed on my mind how to create these ducts.  I’m sure there’s a better or fancier way of doing them, but for me, this is a good start.  If they work that’s great and if not, I at least have a good starting point.  These were the last items needed before cleaning the engine off and sealing the baffles using 3M firestop.

What’s under the hood?

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While I worked on the wiring, I made progress with mounting the engine cowling as I’m really starting the countdown to moving to the hangar.  The cowl had been at the airport for months, so I retrieved it to start measuring and trimming.  With the baffles and plenum initially fit, I started with the mock up prop spinner plate from Whirl Wind.  This mock up has spacers that position the backplate as if the propeller was on, which is then used as the template for positioning the cowl.

I also used the spinner backplate to tac the cowl halves together and do an initial trim on the front joint.  Clecos worked well holding it in place as I trimmed and ensured a good fit resulting in even circular openings for the intakes and prop.

I started with the top cowl, laying it over the fuselage skin and clamping it to the spinner backplate with spacers for a nice clearance gap.  I used the reference line method to mark the edge of the firewall on the cowl overlap and measured twice before cutting it long so I could sand it to fit.

The cut came out well and a few minutes blocking it with sandpaper resulted in a nice fit.  The bottom cowl was next and needed a clearing slot cut for the nose gear leg before even rough fitting.  The Show Planes cowl has a unique fairing that I still didn’t understand quite yet but did know that I need not worry about a finished product at this stage.  I cut the opening as small as I could while giving room to put the cowl in place.

With the two halves fitted and tapped in place, I established the horizontal split line and the Sky Bolt line.  It’s key to establish where the skybolts will go on the horizontal line so that the firewall line can be even creating a nice symetric appearance.  Once the split line was figured out and marked, the bottom was similar to the top for the aft cut and soon the overlap was gone and sanded to fit with an adequate paint gap.

Finally, I trimmed the horizontal split line on each cowl half and used the top as the line to match with the bottom.  A bit of sanding and fitting the bottom cowl 5-6 times, and I was happy with the result.  Next up was to lay out the skybolt holes and install the brackets for the receivers.  The manual gives a target spacing that I was able to hold to pretty closely.  I started from each side’s horizonal split line placement and did a bit of math to evenly space the upper firewall bolts.  I think used the same spacing on the lower cowl each side to confirm no interference with the engine mount bolts.  It’s tight, but it works.  Lastly, the horizontal spacing was calculated and marked.  In the end, the fasteners will be in line and evenly spaced and will look great.

I transfered the locations onto the fuselage skin around the firewall then positioned the tabs for drilling and riveting.  Pretty soon, those were primed, shaped to match the curve, and installed.  Next step is to use drill guides to drill the initial hole through the cowl.  I thought I’d be able to use the light method from inside but with the new grey fiberglass gel coated parts from Van’s, that option doesn’t work.  I couldn’t drill from the inside using the cleco adapters, so I wound up carefully measruing and marking the centerpoint of each tab and making a #40 sized hole to get started.

Once a few holes were in, the adapters allowed the cowl to stay in place and I then used the adapters as sight gauges while progressing drilling the holes big enough to accept the skybolts.  I stopped every few increments on the step bit to check alignment with the adapters in the tabs.  It was a bit time consuming, but the process worked well and I had no issues with all of the holes.

The split line fasteners were the last ones to be installed, as I used some walrus teeth (2×4) to prop the cowl in place and firewall fasteners to secure it.  Laying out the drill holes and then confirming with a #40 hole was the first step.  Unfortunately, you can’t drill progressively since you don’t have a way to hold the clecos adapters in place as sight gauges.  So I installed the tabs and then marked the centerpoint of the hole before taking time to step drill while the cowl was off the plane.  The skybolts have enough leeway to allow a small margin of error, so it worked out fine.

I’m not sure it was really that much more work than the stock method using the piano hinge, but I’m happy with the result.  It’s dirt simple to remove the cowl and I personally really like the looks of the fasteners.  They aren’t for everyone, but they are for me!

Brains and speghetti

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Hanging the engine seemed like a big step, but wiring it and plumbing it is the real work.  I knew the connections to the ECUs and sensors would be a big job, but I thought the days of electrical wiring were mostly over.  Boy was I wrong!

I brought it on myself, really, as I knew using SDS would be deep in a mess of wires resembling an Olive Garden menu.  It’s absolutely worth it though, as I’ll wind up with a powerful and efficient (relatively speaking) engine with lots of tuning ability and choice of running LOP with a simple flip of a switch.

I started by screwing the ECU relay box to the ECU case itself with a few screws tapped into the ECU case.  This creates a tidy package that will bolt into the cabin side behind the subpanel.  I also put the mixture knob relay box on with double sided tape to secure everything in one palce.  I had already mounted rails with nutplates in the subpanel.

SDS supplies a harness with labeled wires and prefabed Dsub connectors.  I fished all the wires that will go firewall forward through the stainless penetration and quickly realized there was no where near enough room to run all the wires.  I still had the CHT/EGT and other EMS wires that needed to come through for the AFS EMS plus a few other misc wires.  Without regards to symmetry, I decided to scrap more of the expensive firesleeve penetration kits and just run with a silicone high temp grommet and fire stop.  The plans call for a plastic grommet and fire stop, so I’m still above minimums here.  Two more holes painfully drilled and deburred in stainless steel allowed enough room for the tangled mess.

I underestimated the amount of connections and sensors needed for everything!  It seemed the wires never stopped and I always had more hanging waiting for their turn in the spot light for a trim and terminal.  Injectors, coils, EGT, CHT, hall sensor, TPS, MAP, AFR, oil pressure, fuel pressure, original bell telephone…okay not the telephone.  I routed everything as neatly as I could keeping in mind strain releif, heat sources, and interference from other wires.  I’m sure someone could do it better or neater, but this is working for me and I’m not really trying to win a neatness contest at this point.  I chose to use zipties for now and will experiment with a 500*F rated sprial loom from McMaster Carr to clean everything up a bit down the road.

I focused on the firewall forward and finally had everything connected and pinned out.  I created a carbon fiber plate for the THREE MAP sensors, yes, three of them.  I also used Bryan at Show Planes’ transducer mounts to avoid more stuff on the firewal and create less plumbing lines.  I also worked on the spark plug wires which use MSD terminals and wires.  They were pretty easy to make up and I went ahead and drained the preservative oil out of the cylinders to install the spark plugs with the adapters and anti-seize.

I did run across my first dumb ass moment when I relized my perfectly placed EGT probes are not perfectly placed.  They are smack dab in the middle of the spark plugs and thus need to be removed to change the plugs.  Not the end of the world, but will add maintenance time down the road.  If I get tired enough of them, I’ll remove the exhaust, weld up the holes and reposition them.  Speaking of welding, I had Charlie on base weld up a mis-drilled EGT hole (interfered with the induction intake) and the AFR bung.  As always, he did an amazing job for the reasonable cost of a few cases of beer for the shop.

Fast forward a week or two, I finished the brains by working cabin side of the firewall underneath the panel.  I just love contorting my body in some ungodly yoga pose upside down while having my face inches away from my work area to work under the panel!  Fortunately, the wife came out and stood by my side as an assistant for the three hours it took me to terminate all of the extra wires inside.  I had to pin out a few switches, mixture knob, sensors, grounds, power, and signal wires for the ECUs and EMS.  It wasn’t fun, but it went well and I got all of the connections made correctly with her help and a lot of triple checking.

We also remounted the air oil separator on stand offs I created and bolted the improperly drilled holes to seal the firewall.  Mounting the ECUs was a rediculously difficult endeavor but thank goodness I had already installed the rails and nutplates.  Without those, it would have been impossible, truely.  I hope I don’t have to get those boxes out very much if ever at all.  The wiring needs some tidying up underneath that I’ll do another day but at long last, it’s all hooked up.  The final step was to fire up the master switch and check out the ECU programmer now that it is installed in the panel filling the last hole.  It’s at long last a complete instrument panel!