nlappos

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Everything posted by nlappos

  1. nlappos added a post in a topic Tire comparison 8.00-8.50's   

    I'll bet it isn't the size or softness, it is the lack of tread. Those look like great tires, how much and where did you get them?
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  2. nlappos added a post in a topic Starting my Homemade Hackman   

    I have a hacman. When the valve is closed, carb function is normal and uses the normal jet. It leans from there, to account for altitude, mostly. And it works.
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  3. nlappos added a post in a topic Starting my Homemade Hackman   

    Here is the jet sizing chart snatched from http://www.ultralightnews.ca/bing/bingjetchart.html
    One thing I noted is that the temp is the carb inlet temp, which can be a lot warmer than ambient air. My 670 has at least 10 deg F temp increase at the carb (I used my wife's meat thermometer to check) so I jetted it for the warmer temp.
     
     


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  4. nlappos added a post in a topic Starting my Homemade Hackman   

    Old data, I pulled it down, the right one says 165 and posting it now.
     
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  5. nlappos added a post in a topic Confused?   

    japowell,
    The going battery for the 582 is a Group U1 lawn tractor battery, at about 25 lbs and about 35 AH, costs maybe $50 at Walmart . Some folks are now switching to Lion batteries at about 3 lbs (!!) but costing maybe $200.
    If you are game to stretch the fuselage, I think it is a great idea if you are 6 feet or more, the headroom and leg room are pretty scoshy on a standard Avid. Adding maybe 2" of legroom and 2" of width, plus a little headroom would be great. But I am 5'11" and fit ok,.
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  6. nlappos added a post in a topic Friendly thrust competition   

    Yep, good read - the static friction of the wheels would have to be added to the total, but you could estimate that by just pulling the aircraft slowly while you read the scale. Then add that number to the static thrust as the scale reads when the prop is wound up.
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  7. nlappos added a post in a topic Becoming a rejuvinated bird   

    1avidflyer,
    I am looking for any creep, and so far all looks good. I suspect the actual movement is all within the flex of the parts, but time will tell. So far the main nut holds torque, the clamp holds torque and the thin channel holds the springs nicely. I did put in an inspection hole and cover so I can get to the top of the bolt to set torque properly.
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  8. nlappos added a post in a topic Becoming a rejuvinated bird   

    I put a double spring on, with a shorter section that extended down to almost touch the tail wheel. I used only one bolt and doubled the spring, but also clamped the short section to the long section with a simple steel bolted clamp, so both springs act as one. This seems to work well, with no mods to the airframe. Here is a close-up that shows the clamp. This way the one bolt and the thin channel keep everything in place.

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  9. nlappos added a post in a topic YAMAHA RX-1 (140 HP) install in Kitfox 5   

    Me too! Next year.
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  10. nlappos added a post in a topic Controls   

    The bank angle tilts the lift from the wings, so some of that lift points to the side, which pulls the airplane in that direction. The trim ball stays centered, showing that the side force is balanced by the bank angle. You can create a turn purely with rudder, since that will make a side force to turn you, but when you do that, the turn is flat and the side force is unbalanced, so you skid and are pulled to the outside of the turn. A banked airplane is exactly like a banked car, where the tilt allows you to feel comfortable as the turn takes place.
    So, the ailerons bank the wings, tilts the lift of the wings so some points sideward, and that turns you.
     
    here is s good, well illustrated discussion:
    https://www.boldmethod.com/learn-to-fly/aerodynamics/the-aerodynamics-of-a-turn-in-an-airplane/
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  11. nlappos added a post in a topic Wind   

    For me the issue is always the crosswind component and the gust spread. I will fly in 25 knots with gust spread below 10k, but it should be nearly straight down a runway. Any length runway, with a real 20 to 25 knots, the Avid lands at maybe 25 ground speed when you walk it on at stall +15 mph.
    If there is a crosswind, I use about 8 knot crosswind as my max component, and even then I am wired. I flew mine in California at 20 to 25 knots with 10 knot gusts down the runway and had a ball.
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  12. nlappos added a post in a topic How to Pop In a New Starter   

    new starter in, and the door closed on the hole.

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  13. nlappos added a post in a topic avid catalina flight   

    Magnificent!
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  14. nlappos added a post in a topic Flight season 2019   

    Beautiful rocket ship!!
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  15. nlappos added a post in a topic E-Tec or Polaris 800 conversions   

    Will
    I think a lot of the forethought has gone into this by the folks who looked at the Yamaha Apex engines, and the gearbox that Teal Jenkins is testing right now (and taking orders on, via his FaceBook page) might be a ready solution. The family of Yamahas delivers 200,000 engines a year since the early 90's, so there is a mass of data on reliability behing them. It seems that there are several variants of the Apex that deliver between 140 and 200 HP, and Teal's gearbox is a dandy solution for the stepdown from 10,000 rpm to something more digestible by a prop. 
    I am sure several other sled engines are also fine, but since several folks are pioneering the Yamaha path, we can benefit from them. I posted this in another similar thread:, here are some links to explore:
     
    I think a cheaper way to get 200+ HP is to look at those turbocharged Yamahas, I saw a fuel injected, turbocharged low mileage sled for sale on craig's list for 3500, plus one of those boxes that are now being tested, (see the thread and FB page by Teal Jenkins) and you could get big horses (200+) for much less that $10K. Here is the FB page: https://www.facebook.com/groups/164864990778457/  and here is the AFF thread: http://www.avidfoxflyers.com/index.php?/topic/5824-yamaha-apex-skytrax-adapters/&page=3#comment-58241
    As far as reliability, these 4 strokes are built by the 200,000's per year. And their part pricing is 10% of the Rotax gouge.
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  16. nlappos added a post in a topic Last year the 670 will work for ac use?   

    I have a Rotax Rick 670 that slips into the 582 mount, and has the Rotax C gearbox on its nose. Works like a charm. I get 600 fpm climb at 9000 feet density altitude here in Utah.  

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  17. nlappos added a post in a topic E-Tec or Polaris 800 conversions   

    Will,
    That shelf concept would work, but a quick thought experiment would tell you why it isn't ideal. A set of struts in the same shape allows you to eliminate all the metal where it isn't needed, and leave strong, hollow members where the stress must flow. My guess is hollow struts would weigh about 15% of what those solid metal thick shelves would weigh.
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  18. nlappos added a post in a topic Operation Cannibal Fox   

    Try this for size, turbocharged, 300 HP, just need that power takeoff gearbox that Teal Jenkins is completing:
     
    https://reno.craigslist.org/snw/d/07-yamaha-apex-supercharged-snowmobile/6774271874.html
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  19. nlappos added a post in a topic Another Flapperon Failure   

    My guess is that failure was caused by bending at the nut, where threads are absolutely vulnerable to bending. The lollypop bearings are supposed to relieve any bending, making the joint purely tension-compression, but if the bearing is trapped, the bending can move down the threads and cause cracking.
     
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  20. nlappos added a post in a topic Where is the MK4 section?   

    skypics,
    Thanks for the info on the Earthx battery, good stuff.
    You can't find the MK4 section because thee isn't one, it is the "Avid Model IV" line on the "Avid Flyer General Hangar" forum. See the screenshot below:

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  21. nlappos added a post in a topic Operation Cannibal Fox   

    I think a cheaper way to get 200+ HP is to look at those turbocharged Yamahas, I saw a fuel injected, turbocharged low mileage sled for sale on craig's list for 3500, plus one of those boxes that are now being tested, (see the thread and FB page by Teal Jenkins) and you could get big horses (200+) for much less that $10K. Here is the FB page: https://www.facebook.com/groups/164864990778457/,  and here is the AFF thread: http://www.avidfoxflyers.com/index.php?/topic/5824-yamaha-apex-skytrax-adapters/&page=3#comment-58241
    As far as reliability, these 4 strokes are built by the 200,000's per year. And their part pricing is 10% of the Rotax gouge.
     
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  22. nlappos added a post in a topic Another Flapperon Failure   

    I wrote the guy twice to try and figure out what I was looking at, he provided the circled sketch. I figure today I'll just pick it all apart (thanks 1avidflyer!) to look at them all.
    culater, I also find it hard to imagine how that can crack without abuse.
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  23. nlappos added a post in a topic AVID C ready for registration, need drawings   

    Mike,
    I think the simple 3-view drawing could be made by using a regular C model sketch, and photocopying it, cut and paste the stretch into the top and side views, and copy that new version. Be sure the dimensions match what you built.
    Beautiful airplane, BTW! Nice job.
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  24. nlappos added a post in a topic Flaperon Torque tube failure   

    I posted a thread about another failure mode for the flapperon controls at this location;   http://www.avidfoxflyers.com/index.php?/topic/6464-another-flapperon-failure/
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  25. nlappos added a topic in Avidfoxflyers General Hangar   

    Another Flapperon Failure
    A Facebook post detailed a flapperon failure on a Mark IV. It concerned failure of one lollypop link in the flapperon controls, which seems to have killed all flapperon control. The poster had very poor english, but posted the below pictures. The plane was in Brazil, the failure was quite recent. The pilot was injured but survived. I posted the pics below, and a sketch of where it lies in the controls. Those rod ends look like Aurora MM-3 and MW-3 that take an AN3 bolt. Aircraft Spruce sells them and the Aurora catalog is at http://www.aurorabearing.com/pdf/aurora-bearing-610-catalog.pdf, see page 12. Even though the rod ends are trapped and can't rotate off, my experience shows that a set nut is required to hold the threads from vibrating and failing. The threaded rod failure shown appears to be because the bearing doesn't rotote freely, and puts the threads under bending - a real no-no.
    I'm going to take mine off today and inspect.



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