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06-29-2010 | 12:16 AM

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dem45133

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From: , NM

RE: Scaling info needed

Thank you both (Kitbuilder and Charley).

Kitbuilder.. I think you right on the power to weight comment... as the idea is to prove out the wing, but I’d like to be close on the stall and cruise Vs.Charley... I've thought about the helicopter... but the mechanical design engineer in me (natural, not by education) sees it as a device trying to self destruct in all directions simutaineously at all times... but one never knows I just might.

Yea... I've looked at basically all the STOL mono-wings... and I still may go that route but pattern after the Pete high-wing open cockpit. My design does include a lot of mechanical innards (nice professional engineering term there, I know!) but its really not that difficult, at least for me. Standard aviation fasteners and pins, all locking. Weight, flutter control engineering, and carrying forces +G and -G will be my biggest problem to control and design/calculate. My budget will be in the $20K range and yes I can do a $30-40K category bird for that amount by not using a conventional aviation engine (which is generally close to 1/3 the cost, if not ½, with most of that cost for their &&^%%$* lawyers anyway) The weight penalty for using a Corvair conversion over the Rotax 912 or 914 is only about 10 lbs (with the appropriate crank mods necessary for any automotive conversion, as all were designed to deliver torque only... not carry prop gyro forces or even lateral PSRUs). The Rotax engine alone is about $20K... comparable Lycoming are about the same. I can build up the Corvair for about $3000... running direct drive at 2700 rpm at just over 1/2 its rated hp, but continuously. I've been rebuilding automotive and commercial engines as well as restoring early 1900s antique engines for 45 years... Its not a problem for me. BTW, these little model engines are very very cool…have to watch that.. I’ll start collecting them. The last third of costs is avionics.

Charley... I do have machining capability. I acquired it a few years ago.... a 1936 Van Norman #12 horz and vert Mill (9x39x17), as well as a 1920 Hendey 14x5 lathe... including both the 3 jaw and a 4 jaw chuck as well as a center stabilizer. Still cuts fine 60 tpi threads like it was new. Both were already converted from their original 3-phase to 220 single, just needed cleaning up and adjusting the clearances. Both work like a charm and still accurate to 0.001.... MY COST... the RT fuel to travel from Cincinnati OH to Rochester NY at 7 mpg to pick them up and haul home... on a tandem axle 12K capacity flatbed antique engine show trailer I built from scratch back in the 90s. Each of the machining units weigh in at about 2600 lbs. I also got another 1500lbs (at least) of tooling. It was a REAL FIND for me... as the primary want of the owner was "a good home" not the scrap yard. I had that... but no money at the time. I had to ask my wife (since we were living on her check) if we could afford the fuel. They then were her Christmas present to me (her idea!).

Yes.. I've been blessed to be a horse of a different color... not much I won't build. My skills are in the top 10% and am meticulous to a fault. The last project was an $800 (yes $800) sight unseen 27ft 30 year old “ready to sail” sailboat with a running outboard. I bought it on eBay. I built up a triple axle 32ft long trailer to haul it home from Green Bay WI with never laying eyes on the boat it was to haul. I had an accurate drawing with one known dimension... that's all I needed. It fit like a glove. I designed the trailer with a sliding triple axle group similar to a semi trailer and fully adjustable everything (although it didn’t need anything but minor tweaks to the bunker’s height... which BTW slid up and down in slots cut buy the above mill)... able to haul up to 18,000 lb gross and 31 or 32 ft 15,000 lb boat. The sailboat lives home too. Its in a shed. The trailer cost three times what the boat did in new and used materials, but 1/4 the cost of a factory and built with MY features. It took me three weeks to build full time. A year later I salvaged another hurricane damaged boat for the inboard… the 1650 lb lead keel paid for the trip to FL. I’ll pull anything anywhere and did so professionally in the mid 80s (OTR). I just recently was finally able to buy a Cummins diesel 1 ton 4x4 dually with 5th wheel and gooseneck hitches and all Chrysler’s whistles and bells … its 9 years old but only 100,000 miles and show room mint. It will relieve my 242,000 mile gas v8 ’94 heavy ¾ for the heavy work its been doing rather routinely for 15 years now. It’ll be 10 years before I let the 1 ton see salt or the woods… maybe never… I’ll always have an old beater around for that duty.<o

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>Some people watch TV after work… I go out to the shop and build or restore something. I’ve never used my wrenches to earn a living.. it wouldn’t be fun then… I am a Environmental Scientist specializing in hazardous and radiological waste management. Have been for 20 years now. Yes, sometimes my co-worksers don’t believe my project stories until I show them the pictures or they come out to our place. It took 16 years, but my later-in-life Master’s degree is finally starting to pay off. I was also farm born and raised (rented, not owned) which is where most of my mechanical skills developed… very early in life. Dad was also a machinist…so I learned something of that too.<o

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>Dave

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