Quad racing motors in single motor "prop in slot" Park Jets

Discussion in 'Electronics' started by e3_Scott, May 24, 2018.

  1. LukeWarm

    LukeWarm Top Gun

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    I seen a few post where the they were complaining about the position of the prop in the slot when using the shorter motors. I do understand the concern because the prop performs more efficiently if it is in the middle of the slot. I also like mounting the prop in the middle of the external part of the motor's shaft. This problem is easy to fix. When building the jet and cutting it out, add an addition half inch or so to the mount's length. Cutting the excess off with a razor blade is easier and lighter then adding more to the mount later. This also allows for a perfect custom fit of any motor.
    I like two bladed props better because, for general use, length is king. If you want more reading in this subject area, try these.
    The-Science-Behind-the-Slot
    The Components of Thrust; How to choose a propeller.
    An Airplane Propeller’s Pitch
    How to get the most out of a motor
     
    Last edited: Dec 25, 2018
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  2. e3_Scott

    e3_Scott Top Gun

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    Thanks for your input. In my experience and testing these quad motors in park jets for well over a year and a half, I just left the motor mount where it is and trim the leading edge of the prop slot forward to open up the prop slot area which I wrote about in the original post of this thread. This does sometimes require shortening the fuselage and the nacelles underneath, but is not that difficult to do and tends to keep better balance on the plane by keeping the weight of the motor closer to the CG. All testing I have done is with two bladed 6" props of several different pitches, prices and manufacturers.

    Cheers,

    Scott
     
    Last edited: Dec 25, 2018
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  3. LukeWarm

    LukeWarm Top Gun

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    Scott. You've made many great threads and post, thank you for all that you do for this forum.
    CG can be easily adjusted by battery servo and receiver placement, but if the slot is cut much larger, this affects the look and aerodynamics of the jet. As you can see by my post, I've done a little experimentation with the slot. My son designed the PDF tiling system and a good part of most of the jets that were sold by this site. During the designs, slot placement and size underwent scrupulous evaluation. I know because I was there for some of it. This is one of my son's threads. Split-Elevons!
    If you would like some more CG info, check out this thread I made many years ago. Useful-Center of Gravity-Information
     
    Last edited: Dec 25, 2018
  4. Great Info :)
     
  5. e3_Scott

    e3_Scott Top Gun

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    Hi Everyone -

    This video is not so much about quad motors, but I didn't see the need to start a new thread:) Basically a review of what I got up to in 2018 and some thoughts about projects I will be looking to work on in 2019. As mentioned in the video, I will be doing some long term reviews on many of the motors/ESCs and batteries I have been using since spring/summer of 2018 to provide my feedback on how they have held up after continued aggressive use.

    Cheers,

    Scott
     
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  6. Keep up the excellent work Scott and Happy New Year to you also. :)
     
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  7. e3_Scott

    e3_Scott Top Gun

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    Hi Everyone -

    Since becoming involved in testing quad motors in my park jets, I have been following Joshua Bardwell on YouTube (his channel is here https://www.youtube.com/user/loraan/videos). Much of what he discusses does not pertain to my needs in the hobby, but I do learn something from most of his videos and have enjoyed his interviews with Ryan Harrell who runs miniquadtestbench.com https://www.miniquadtestbench.com/ This video shows a little more insight into Ryan's test lab and the lengths he goes to try and keep the data as accurate and consistent as possible.


    Perhaps a bit technical for some, but certainly a reminder to me that environment, batteries and other things do play a part in motor testing and the numbers I might get or performance I might see at the field could be far different than other folks. I live about 200 ft above sea level and being close to the ocean and in a "temperate rain forest" climate zone, my numbers could be far different than someone at higher altitude, drier climate, etc.

    What I have noticed over all the motors, props, ESCs and combos thereof is that often bench testing does not tell the complete story when I get to the field. Bench testing allows me to find whether a prop is too much for a motor based on amp draw or allows me to ensure I match the correct ESC and battery to the motor/prop combo to prevent burning something out. Often as with the RCINPOWER GTS2306 V2 2750 kv motor mentioned in a previous post, the performance at the field is slightly better when compared to other motors, sometimes I have found it to be worse. I shot this video awhile back discussing my thoughts and lessons learned comparing bench and field testing.


    Cheers,

    Scott
     
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  8. e3_Scott

    e3_Scott Top Gun

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    Hi Everyone -

    A brief video discussing my initial impressions of the RCINPOWER GTS2306 V2 2750 kv motor now that I have about three flight sessions complete with it. Motor link https://www.banggood.com/RCINPOWER-...s=mywishlist&ID=515953528524&cur_warehouse=CN Links to all the other components discussed can be found in the comments below the video on YouTube or hear on the motor test spreadsheet https://docs.google.com/spreadsheets/d/1KLR_wdkJ1OdGcf5f9jxxxU8qqmz_kXjMQH8NOLjW3NQ/edit?usp=sharing


    Cheers,

    Scott
     
  9. e3_Scott

    e3_Scott Top Gun

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  10. e3_Scott

    e3_Scott Top Gun

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    Hi Everyone -

    I still had a little Christmas money left over that people were kind enough to give me and when notification for this video showed up in my inbox today, I couldn't help myself...plus it was on sale for 29% off :)


    3400 kv is the highest kv I have seen yet on a quad racing motor of the size I would use in a standard park jet. The motor testing part of the video starts at about 11:55. His equipment shows that this actually a 3400 kv motor and on 3S with the King Kong 6040 prop discussed in the post above is producing 1606 gr/56.6 oz of thrust, although with a pretty hefty amp penalty of 62.7A which would probably be closer to 45A in the air. I do still have a bunch of 3 bladed quad props I had picked up but never really tested, so might play with those also on 4S if I have an ESC that can handle the amp draw;)

    #ParkJetnoise

    Cheers,

    Scott
     
    Last edited: Jan 13, 2019 at 12:42 PM
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