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Mike Cuy's Building Notes

 My Pietenpol wing is rigged to have 3/8" washout at the aft end of the 3rd rib in from the end of each wing.  Much like a J-3's washout or Aeronca Champ's washout are set at.   My ailerons were rigged to each have about 3/16" to a 1/4" droop on the ground with stick neutral.   The older IA's at my field who helped me said this practice was commonplace on Cubs to DC-3's and the idea is that during level cruise the airflow over the wings pushes the ailerons up to the neutral position taking out the bit of normal play in the aileron cable system. I believe my dihedral is about an inch at the wingtips.   What I've found on my Piet is that an improperly rigged (twisted) horizontal stabilizer can make you think you have a wing (roll tendency) rigging issue.   You can even have one elevator rigged a little higher or lower than the other and it makes like a wing issue so sorting these things out in your flight test period is helpful in whiling away the hours in your practice area.    My Uncle Tony Bingelis has some excellent passages about rigging and flight testing our airplanes to get them to fly as hands-off and cleanly (there's a word you don't hear too often associated with Pietenpols) as possible and this relates to gentle and straightforward stalling characteristics as well.    The Piets I have flown with no dihedral fly just great but for hands off, folding charts, reaching down for wayward sunglasses on the cockpit floor in flight kind of times the ones with a little dihedral don't wander as much in roll.  

Smoke System

the smoke setup I have is still as per original idea and is about as simple and reliable as you can get.  I use a 2 quart poly pump-up bug sprayer from the Wal Mart garden department, hacksaw off the plastic handle, remove the spray wand and discard and adapt 1/4" plastic airspeed tubing to the sprayer nozzle with rubber hose and either tye-wraps and or hose clamps. The 1/4" poly line is connected to a 1/4" copper, stainless, or aluminum tube which connects to a fitting (mine is a Swaglok fitting) that you weld into one of your aft exhaust pipes (they run hotter than the fronts on 65 Continentals) about 1-2" down from the flange. On the ID of the fitting that is welded to the exhaust pipe you drill two No. 60 drill bit holes in your exhaust pipe wall and whala, you have a smoke system.    (I suppose you could drill one hole with the same equivalent area but have not tried that) Might want to put a vibration loop or two in your metal tubing from the firewall to your exhaust stack to dampen the stresses and strain on the tube so your metal doesn't fatigue.    The smoke oil I use is Texaco Canopus No. 13 which is basically a mineral oil.  They used to call it Corvus oil.    Every other year the Thunderbirds park at our NASA hangar when they are in town and I salivate beyond measure when I go up there and see beyond the cyclone fence about a dozen 55 gallon drums of the smoke oil ready for the Thunderbirds to use in our airshow.  

Brakes

I purchased Comet brake calipers at a local lawnmower/ go-kart shop   http://www.hoffcocomet.com/comet/aftermarket-brakes.asp  (scroll down when you get there) and traded aerial photos of a machinist friend's home for him to turn some rotors that fit my wheel hubs.  My wheels are 19" and my rotors are 6" in diameter and the Comet DC Series caliper just hold me for run-up and no more---which works out fine.  As you've seen my plane at Brodhead, I made up heel brakes ala Cub/Champ and actuate the calipers with 1/16" cable.  Lots of ATV brakes out there too now which I'm sure would be worth looking into Depending on what suites you. 

Fuel Tank

My behind the firewall tank is just like Jack's being 5052 .040" and TIG welded.  I have the tank well supported so it doesn't oil can on me that I can tell and no leaks after 300 plus hours.   Used Fuel Lube on the screw-in fittings.  Small can will last you two or three lifetimes and to share with other homebuilders.  I liken it to cold bees wax...very stiff and sticky but better than using teflon tape (which is verboten in fuel systems...see Bingelis books) or other goop  

Weight and Balance