marcusofcotton

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Posts posted by marcusofcotton

  3. Posted

    Dot 5: WRONG

    MIL-PRF-5606H: RIGHT

    Just say'in that you can't go wrong with 5606. You don't need but a liter or so and will have plenty extra for future bleeding.  I'd source it at the local aerodrome maint shop.

    I'm inclined to agree...

  6. Posted

    TJ, what prop are you using?

    64/34 Tennessee, its to much prop but it works for now, later on there may be a 68inch luga in my future plans

    That Luga should get it off short, have you heard of anyone else putting that large of a prop on the Jabiru before? I purchased that very slightly used 62/32 that Lonnie Prince had, surely a nice improvement for my short field.

    Only know of one other that has the prop on a Jabiru and he seems to like it. That prop that you have I looked at that one last year. What did it do to your cruise?

    I was expecting it to drop but it didn't seem to, might be something to his varying pitch design - it seemed to work for me. If I was to order another from him, I'd probably try 64/32.

  7. Posted

    TJ, what prop are you using?

    64/34 Tennessee, its to much prop but it works for now, later on there may be a 68inch luga in my future plans

    That Luga should get it off short, have you heard of anyone else putting that large of a prop on the Jabiru before? I purchased that very slightly used 62/32 that Lonnie Prince had, surely a nice improvement for my short field.

  9. Posted · Edited by marcusofcotton

    Perhaps I should've explained in the original post that I was using one clamp on the top side and one on the bottom. It went pretty well for me, but the bungees were not new either.

  11. Posted

    Doug,

    ~12 years ago did the course for weight shift control. Last year I stayed after at Oshkosh for the fixed wing airplane version so I could get the certificate for my Avid. This time from Brian and Carol Carpenter/Rainbow Aviation, guessing same folks for you?. I got more out of it than I expected, Brian and Carol did a great job. I don't recall the balance other than a fair bit of time on the regs as some have a hard time getting it. Don't worry about prior knowledge, you'll do fine from what I've seen on the list. You'll be bored at times but it works out okay. 

  13. Posted

    A few more details:

    Weight for entire gearbox/adapter (with oil) is projected at slightly under 19 lbs.  Installed engine weight (total with everything fwf) falls in the 165 - 185 lb range.

    Final gear ratio is 3.83:1 with the broad powerband of the Apex in the 6200-8300 rpm band (pto) (approx 120-162 hp for the 2011+ Apex)

    The prop flange is designed considerably higher than the RX-1 w/ C box.  This is a big improvement since with the RX-1 we had to make a bit of a compromise with regard to prop height (low if you try to tuck the motor under the cowl... or raise the motor for a better centered prop which would necessitate upper cowl mod)

     

    Note: power chart below is pto rpm (after 1.23:1 internal reduction, so crankshaft rpm would be figures below x 1.23)

    chart.jpg

    What does one need to do to open this chart? I get 404 error. To get prop speed do I need to divide engine rpm by 3.83 and 1.23 or just the 3.83?

    Thanks!

  16. Posted

    The simple answer is no. But there are many variations of each engine which will affect the weight.

  17. Posted

    One disadvantage to powder coating is that it hides cracks until they are bigger. Agreed that it looks nice and is tough.

  18. Posted

    Absolutely run the thermostat like Jim says. Sorry I haven't gotten out to get the nose wheel pictures for you yet, been pretty busy here.

  19. Posted

    I'll try to get some pics after work tomorrow night. This is a Matco unit, you might give them a call, probably can buy complete for less money and the engineering is done. I don't know for sure if the spring section is solid or hollow, guessing solid, steel but unknown alloy.

  21. Posted

    Steve, I'll try to get some pics soon, hopefully tonight. Thousands of aircraft out there with free castoring nosewheel. It is a bit different at first but you get used to it very quickly.

  22. Posted · Edited by marcusofcotton

    You should be able to purchase an RV6A assembly (the one of your pics with the unfinished wheel pant). That's what I have on mine (including Avid drawings for same). I'm planning on taking mine off later this year to install Grove taildragger gear I purchased. Thought about selling it but I'm kinda thinking of hanging on to it as a boost should I sell in the future when the Bearhawk is done. Although I'm really falling in love with this bird. Thinking about the possibility of the enclosed trailer route for retirement ( or pre-retirement) travels... 

     

    As Ed mentioned, it also provides stabilizing compared to the original style Avid nose gear as it puts the wheel farther forward.

    20170716_182017.jpg

  24. Posted

    I have never seen the original aluminum tanks (that cracked...). The traditional fiberglass tanks are a structural part of the wing. I the aluminum tanks were conceived the same way the flex of the wing could/would crack them.

    But if the tanks are "free floating" within the wing there would be no stress an they would remain intact - but we would loose the structural function of the tank. With no tank installed in the wing there is a diagonal tube in place.

    The only real issue with the original fiberglass tanks is if they are not compatible with ethanol. So if a ethanol resistant resin is used I don't really see the issue with the traditional tanks. 

    The issue with having multiple connected tanks in the same wing isn't so much the fuel flow out as fuel in... unless the connection can manage the flow correctly. 

    Fred

     

    Free floating would be good, unfortunately with the original fiberglass tanks cracks can develop from the stresses even without ethanol. :o(  I like the idea of rotomolded, not sure how much weight gain there would be though.

  25. Posted

    Without crunching any numbers, you have A drawn in at 45* to horizontal. Any upward wheel movement would be greater than outward movement from that point up, very close at that point. Were you thinking 4" spread between the two wheels? Only 2" upward movement before spring bottoming would be of great concern to me. Better buy bushwheels and keep the pressure low. ;o)

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