---------------------------------------------------------- RV8-List Digest Archive --- Total Messages Posted Mon 10/19/09: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:12 PM - Flap Motor repair attempt report (Vincent Himsl) 2. 09:49 PM - Dynon, tachs, transducers, pulses and more oh my (Vincent Himsl) ________________________________ Message 1 _____________________________________ Time: 07:12:23 PM PST US From: Vincent Himsl Subject: RV8-List: Flap Motor repair attempt report Hello=2C I attempted to repair my flap motor and this is my report. Problem: Wires broken frayed at entry to flap motor housing. Solution: Not touching the worm gear i marked case and dissassembled the motor. The o nly items removed from the airplane were the end=2C brush assembly and outs ide case (stator?) of motor. Discovered that the wires entered the black plastic brush assembly. My assembly snapped together and wasn't glued thus I was able to separate t wo halves with a Jeweler's screwdriver. Soldered new wires to stubs inside housing. Cavities inside housing allowed me to reroute the wire without the solder joint causing an interference pr oblem. I cleaned the rotor and brushes. Rotor was clean and didn't have much oil o n it. The brushes however had a kind of varnish coating. Burnishing the bru shes fixed that. I didn't do the grease removal that is mentioned a lot on the list. Why? I took the rotor in my hands and manually rotated it to determine the load the motor felt raising and lowering the flaps. The feedback force is essent ially zero even with my leaning on the flaps to restrict their movement. I saw no evidence of grease working its way up the rotor. I reassembled the motor and tested. Works great and I didn't spend $300 plu s bucks for a replacement. Will let you know if motor goes south in future. But for now=2C I need to w ork on my 40 hours so as to make my RV-8 a respectable airplane. Vince H. RV8 N8432 20 hrs. _________________________________________________________________ Hotmail: Powerful Free email with security by Microsoft. ________________________________ Message 2 _____________________________________ Time: 09:49:08 PM PST US From: Vincent Himsl Subject: RV8-List: Dynon, tachs, transducers, pulses and more oh my Hello=2C After exhaustive searches=2C I broke down and read my Lycoming manual. I kn ow=2C like asking for directions and admitting you're lost. I have a Van's tachometer transducer connected to a Dynon D-180. Now the tr ansducer puts out 8 pulses per revolution but I=2C like most=2C had to set it at 3.5 or 4. Why? Well... the Lycoming manual clearly (when actually read) states that the ta ch transducer output gear turns at a .5/1 ratio. In other words when the en gine rotates once=2C the tach transducer output rotates 1/2 turn. If you se t your Dynon tachometer input to 8 pulses/rev=2C you will get half the RPM. Doing the math:(.5 Trev/Erev) x (8 pulses/Trev) = 4 pulses / Erev which i s where most of us have been setting the Dynon using trial and a lot of err or. Trev= tach port rev Erev= engine rev pulses= transducer pulses. Hence the 4 (some 3.5) pulses per engine revolution. Again only a compariso n with a calibrated tach (tru-tach) will let you know for sure how close yo u are. Now if I am wrong=2C don't tell me for it appears to be working. Vince H. RV8 N8432 20 hours and 'climbing' _________________________________________________________________ Hotmail: Powerful Free email with security by Microsoft. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv8-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV8-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv8-list Browse Digests http://www.matronics.com/digest/rv8-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.