nlappos

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Everything posted by nlappos

  1. nlappos added a post in a topic Shipping engines   

    Simplicity is essential. Rotax Rick says to use a big plastic tub, lots of pillows, and ratchet tie-downs. I did this to send my 582, and he used it to send back the 670, and it was perfect. He sends and receives dozens of engines this way. I used Fedex Ground, cost about $250 each way across the country (Utah to Florida), with declared value of $5000
    Zero bother, too. Here is Rick's discussion:
    https://rotaxrick.wordpress.com/shipping/
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  2. nlappos added a post in a topic My Wheelbarrow is getting closer   

    I saw this in Star Wars, didn't I?

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  3. nlappos added a post in a topic Tailwheel spring design   

    I had Wausau Spring make me a tail spring, they did a good job.
    http://www.wausauspring.com/
     

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  4. nlappos added a post in a topic MK4 Engine swap   

    The Rotax Rick 670 is a viable alternative, and a drop in. I uses the 582 mount and fits like a glove, produces 91 HP and starts and runs great. It costs about $3750 plus your old 582 for a zero time 670.
    The whole story:  http://avidfoxflyers.com/index.php?/topic/5734-new-rotax-670-install/
     
    Rick's pricing page:  https://rotaxrick.wordpress.com/pricing/
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  5. nlappos added a post in a topic Bush gear failures   

    109jb,
    I think your math looks great and we agree!  
    I think an easy way to check the poly disks is to just put the diagonal strut together, and put 2400 lbs of tension on it to see the deflection. A simple rig with a hydraulic cylinder and a strong mount should do the trick. Or you could pick up a VW beetle with it!
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  6. nlappos added a post in a topic Bush gear failures   

    I did some trigonometry on the gear dimensions and angles in your sketch, which seems to agree with the basic dimensions of my Highwing llc (Fitt) gear, shown below. The force on the diagonal rod with the disks on it is about 2400 lbs of stretch on the rod during a reasonably hard landing (3 g's, about 8 feet per second sink rate).
    That means the poly pucks will see a compression of about 2400 lbs during that event. For my springs on the Highwing gear, that compresses the steel by about 1.5",  and at 3.8 G's, maybe 12 feet per second, it compresses the spring completely.
    It might be great to see what the compression on the poly pucks is at that load, 2400 lbs, just as a comparison. the durometer doesn't measure spring rate at all, it is a measure of how the material resists being dented by a sharp pressure. My guess is the stuff is very stiff and would work well as a stiff spring.

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  7. nlappos added a post in a topic Avid MK4 For Sale.   

    aschlem, you wrote, " it has carried a AW inspection up till i bought it." 
    Can you clarify - does the aircraft have a current experimental airworthiness certificate?
    Thanks
    Nick
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  8. nlappos added a post in a topic Heated Seat   

    Power draw for seat heaters? I checked two that are sold at Walmart, both were 48 watts, about 4 amps. Easy load for even a 582 (175 watts total).
    https://www.sojoyusa.com/product/universal-12v-heated-car-seat-heater-heated-cushion-warmer-high-medium-low-temp-switch-45-minute-timer-black/
    https://www.walmart.com/ip/Asdomo-Car-Seat-Heater-Cushion-Warmer-Cover-Winter-Heated-Warm-High-Low-Temperature-12V-Heated-Seat-Cover/997437231
    And 1avidflyer, for temps below -30, they invented GPS so you can easily find Key West!
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  9. nlappos added a post in a topic Building wings without washout   

    Washout is primarily a safety concern. Making the root at a higher angle of attack means it stalls first, giving you stall warning ( buffet and pitch nods), but keeping the tips unstalled and roll control still available. If the whole wing stalls at once, roll control can actually reverse, since the flaperons call for more angle of attack, so the down flap wing might stall first.
     
    I'm not sure what advantage you think you'll get with zero washout.
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  10. nlappos added a post in a topic Rotax 582 RaDIATOR CAP Woes   

    The common manual for the gray and blue head 582's all call for the higher pressure now. 
    Installation manual, all 582 models, gray and blue head:
     

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  11. nlappos added a post in a topic Leveling the fuselage   

  12. nlappos added a post in a topic Garmin GTX327 Mount   

    Yingling Aviation, $41.   https://cessnadirect.com/011-00677-01
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  13. nlappos added a post in a topic Avid Flyer Angle of Incidence   

    Supermotive, I am pretty sure the airfoils are NOT standard, one member a while back even published the airfoil coordinates as a result.
    I have in my files an old, old build book that defines the wing construction for the MK IV and the Speedwing, and the wing incidence angle method for the speedwing is not mentioned, so it might be the same method as the MK IV. Below is the manual section defining the wings, the addendum pages 2A-1 thru 2A-5, which starts off "Speed Wings are constructed exactly the same as standard wings, except for the changes identified in this addition to the manual."






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  14. nlappos added a post in a topic Avid Flyer Angle of Incidence   

    Super, the wing incidence/fuselage angle procedure is in the Build Book, which is in http://avidfoxflyers.com/index.php?/topic/4220-avid-mk-iv-build-manual/
    See Sec III, chap 8 for how to level the fuselage, and then Sec VIII, Chap 6 for how to find and set the wing angle. This will set the angle of incidence to the "factory" (ahem!) setting.
    I took the liberty of snatching them here:
     




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  15. nlappos added a post in a topic NR Luga prop deliveries   

    Could be, Jim. It was about 18 months ago.
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  16. nlappos added a post in a topic NR Luga prop deliveries   

    My stepson bought a Luga from the Ukraine, and it only took a few weeks. He said the quality was excellent, and the price and customer service (several phone calls) was superb.
     
    http://www.lugaprop.kiev.ua/catalog_en.html
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  17. nlappos added a post in a topic Wing rigging issue   

    Kent,
    I think you are saying that from the rudder hinge line to the end of each wing (maybe 18 feet?) the two wings differ by 1 inch on that pair of diagonals? That is darn straight, frankly. The wings are 144" long and 1" fore and aft swing is about 1/3 of a degree out of line. That wing is aligned by mounting it by the two spar ends, and the spars are 27.5" apart. If the forward spar end of one wing butts 0.2" closer to the centerline of the airplane, that wing will be 1" more forward than the other.
    Tjay's idea of pulling a string across the entire wing forward spar just to see that alignment is a good one. If one wing is a bit swept, the fix might be to see how the root end butts into the fuselage.
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  18. nlappos added a post in a topic New Rotax 670 Install   

    Ethanol earned a bad name when first introduced (1990's?) because it dissolved the carb seals and such and made a real mess. Now, all that is far behind but the Internet Gurus haven't learned anything in the 20 years since. 
    Rotax PREFERS ethanol over avgas because it is much more anti-knock , Rotax's worst enemy, and the seals and such are all designed to easily handle it. Four week old avgas loses some of its octane, and is more risky for Rotax engines, and they tell you that. Ethanol doesn't lose its anti-knock properties so fast. WWII fighters uses alcohol injection to raise the octane of their engines and gain more power.
    Also, ethanol gets its anti-knock without lead, unlike avgas, which leaves lead deposits like crazy.
    The reason why I posted the pages from the engine manual is because the internet gurus never read it, and don't believe it even if they did. After all, what does the engine designer know about his engine?
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  19. nlappos added a post in a topic wing spars for Europe   

    One solution might be to ship shorter spar sections, perhaps 3 or 4 feet, and assemble them in Europe. If you use 2.5" tubing, and epoxy a doubler over the joint (6" length of 2.75" OD, 2.5" ID, 0.125" wall section), you would be very strong, and each section would weigh about .6 lb. You'd have some visible rings around the spar at intervals, but what the heck!
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  20. nlappos added a post in a topic Vote! Vote! Vote! Vote! Vote! Vote!   

    This year's election is just like all others. The President is elected on the Monday after the second Wednesday in December, December 17 this year. Until then, the person with the most apparent votes (call him Joe Biden this year) is called the President Elect, and only cry babies weep in their soup and decide not to let the system progress.
    I couched dozens of Little League teams, and none of them had behaved like trump. They'd never play another game if they had.
     
     
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  21. nlappos added a post in a topic New Rotax 670 Install   

    Yes, I run high octane ethanol mix, and Rotax recommends it over pure gasoline! The internet mythology about gasohol is simply amazing. If you read the Rotax ops manual, the higher octane of gasohol is strongly favored over pure gasoline, knock is an engine killer, and alcohol stays high octane. The normal octane enhances of gasoline wear off in a few weeks, especially if the gas is stored a while.
    Note that the lead in high octane gasoline is not at all attractive to Rotax:

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  22. nlappos added a post in a topic 670 info   

    Anders, here are some close-ups of my exhaust



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  23. nlappos added a post in a topic New Rotax 670 Install   

    I love mine. It starts and runs great, and delivers the power it is supposed to. The rave valves cut fuel consumption so it doesn't burn much more than the 582 (at the same power). It also only weighs maybe 10 lbs more than the 582, for 91 HP. At my altitude (6000' pressure, 9000-10000 ft DA in the summer), it delivers about 65 HP, so I get decent performance.
    The only negative side is the extra power needs more cooling, so the belly radiator is needed.
    Rotax Rick did a great job, his workmanship was perfect, and he really helped me on the install, always returned my calls quickly. 
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  24. nlappos added a post in a topic Air Screw   

    I used this video for the basic setup of my carbs, and found it really helpful. https://youtu.be/PiZh1Ox1vmA
     
    Allen , I am sure you know this, but for those who are looking to learn from these informative threads, here is the source material.
    The thickness of the needle controls the mid-range mixture, with numbers 272, 274, etc used to control mixture in this area, see http://www.ultralightnews.ca/bing/rotax-bing-54-carburator-tuning-and-troubleshooting.html
     
    Engine sputter or misfires (0 - 1/8 throttle)
    This area is controlled by the low speed or idle jet, and air mixture screw. Check to make sure the jet is clean and the proper size. Check to see the air mixture screw is set correctly.

    Engine sputter or misfires (1/8 - 1/2 throttle)
    This generally indicates a lean fuel mixture. Check to make sure your needle and clip are in the right position and are not damaged. The air screw still has some effect here.

    Engine sputter or misfires (1/2 - 3/4 throttle)
    This area is controlled by the needle jet and jet needle. Verify that you have the correct jet and needle jet. Also verify that they are located BELOW the white plastic retaining cup. If they are located on top of the retainer the engine will run rough in all ranges, since the mixture is wrong in all locations.
    The mid range is controlled by the needle and needle jet. The needle jets are available in various sizes with the larger numbers giving a richer fuel mixture and the lower numbers a leaner mixture.
     
    Here are the various jet needles:
    https://www.aircraftspruce.com/catalog/eppages/needlejetbing54.php

    A reported problem with ALL Bing carbs is with failure of the jet and or needle clip. This can result in erratic running, lean fuel mixtures, engine returning to and idle during flight.
    To determine whether you need to adjust the needle jets you require a EGT gauge and tachometer.
    For example:
    Many owners of 582's have reported high EGT readings in the 5600 to 5800 rpm range using the stock needle jet of 272 - using a 274 or 276 eliminates this problem.
    Owners of older model 532 report having a problem keeping the engine set at 5400 rpm. It would jump up and down from 5400 to 5800 resulting from  a lean fuel mixture. Again the larger jet usually cures this problem.

    Engine sputter or misfires (3/4 to full throttle)
    This area is controlled by the main jet. Check to make sure it is in place and snug. Make sure there is no water in the bottom of the float bowl. Make sure the needle and clip are in good working condition. If the needle fails around the clip retaining area this will allow the needle to jump up and down causing erratic running. Proper float level is also important here to little fuel flow can cause an lean mixture while to must flow can result in a rich mixture.
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  25. nlappos added a post in a topic Landing gear drawings   

    Lowell Fitt has a nice design that he sells as a kit, I put it on and love them. I can get you his email if you pm me.


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