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  • #61
    Originally posted by Brian Jackson View Post
    Tailboom Standoff cones test fit. Their tips will connect to thin jury struts in tension (via turnbuckles) to the midpoint of the bolt at the aft end of the engine mount. They work opposite of a single compression strut (not shown). More to follow. Some things just take more time than one might anticipate.
    Them there concave tapered thingamajigs look pretty nice.
    I could make me a pretty nice pot pipe outta one of those !!!
    Nice job Brian
    Style and detail won't make it fly any better, but it will surely look nice.
    Life,The leading cause of Death

    Live and Learn--OR--Die and be an example

    321.252.7705

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    • #62
      Originally posted by gyrojake View Post

      Them there concave tapered thingamajigs look pretty nice.
      I could make me a pretty nice pot pipe outta one of those !!!
      Nice job Brian
      Style and detail won't make it fly any better, but it will surely look nice.
      Thank you Jake. Was going more for a Hookah than a bong :-) Actually the shapes of the fittings (and many other parts) was dictated by load; thickness can diminish at a proportion to length. I just removed material where it wasn't needed and you end up with the shape of pulled taffy.

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      • #63
        Ordered the wheels, tires, axles and innertubes today from Azusa. 6" and 4" AzusaLite wheels for the mains and nosewheel respectively. Not having ordered these types of parts before exposed my ignorance of many things. For example, tires... many tread types, plys, profiles, etc. But after studying their site and catalog for a couple of days I think my best guesses were at least somewhat educated before ordering. I went with simple Ribbed tires instead of other tread types like Knobby, Turf, Sawtooth, etc. Flat profile on the mains and round profile on the nose.

        I did not order any bearings with the wheel halves because I am told these need to be replaced with better quality. Will be ordering them from Aircraft Spruce if an Aurora equivalent (or better) is available.

        Axles... where to start. I relied on the Forum for guidance here because the GyroBee plans are vague here and simply spec "KB2 Axles". I did order 5/8" diameter solid steel X 8-3/4" long, no step, with a 1" threaded end. From the plans this appears to be the correct length. They are referred to as "Mini Axles" in the Azusa catalog. They will require aluminum sleeves that are 3/16" wall to fit tight. Since they are 5/8" diameter continuously, the thru-holes for the strut fittings will need to be centered very accurately to leave 3/16" of steel on either side of the hole. I'm a little concerned about this detail.

        Anyway, that's where the project is at currently.
        Last edited by Brian Jackson; 10-15-2018, 12:16 PM. Reason: typo

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        • #64
          This is the gyro with the adjustable camber as discussed.
          A close up of the connection plates to give you an idea of what's going on..
          Last edited by gyrojake; 10-15-2018, 05:20 PM.
          Life,The leading cause of Death

          Live and Learn--OR--Die and be an example

          321.252.7705

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          • #65
            Thanks Jake. I will analyze the photo when time permits this evening.

            Also to add, I believe I may have misspoke about avoiding the Azusa wheel bearings in my earlier post. Searching the forum archives revealed a post I was incorrectly remembering that instructed to "Use the better bearings." It didn't say avoid them. So I apologize for the wrong information.

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            • #66
              Azusa has 2 levels of quality for their bearings. Super cheap stamped race loose bearings, and sealed bearings with hardened and ground races. I've never had a problem with the good ones.
              "Nothing screams poor workmanship like wrinkles in the duct tape!"
              All opinions are my own, I've been wrong before and I'll be wrong again. Feel free to correct me if I am.
              PRA# 40294

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              • #67
                Originally posted by Jazzenjohn View Post
                Azusa has 2 levels of quality for their bearings. Super cheap stamped race loose bearings, and sealed bearings with hardened and ground races. I've never had a problem with the good ones.
                Good to know, John, and thank you. I ordered the Azusa precision bearings today from Aircraft Spruce. Was surprised they're less than $2 each. Bargains usually makes me skeptical.

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                • #68
                  While the Forum is currently suffering some coding issues I'll add this entry that doesn't require photos. Bearings are seated, nosewheel assembled and inflated, and I went ahead and ordered the round profile tires for the mains to replace the square profiles I'd ordered earlier to reduce parasite drag. This was a good bit of practical knowledge available through this Forum that would be tragic to lose, so am hoping the Forum issues can be resolved soon.

                  Having conversed with Azusa Engineering directly, I have decided to bend the axles themselves rather than the axle strut tubes. This is allowed without the need for subsequent heat treatment, and the steel is ductile cold rolled so no issues with fracturing in the ~10 degree range needed.

                  Currently there are 2 fabrications going on: Strut connections for the tailboom supports, and lathe work for the axle inserts. Also fashioned a crude hoist from a ratcheting strap to make the ship a little easier to work on. Am confident the Forum will be running smoothly again by the time there's any interesting photos to post.

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                  • #69
                    Descriptions in photo panels. 2 more posts to follow with photos in each of the component parts for the tailboom support. The thinner airfoil shaped struts are in pre-load tension while the singular wider airfoil strut is in opposing compression. It is surprisingly lightweight (hollow machined cones) while being extremely rigid. The turnbuckle system provides a means to control pre-load stresses.

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                    • #70
                      Tailboom compression fitting. Not shown in photos are 2 opposing milled flats on the upper tenon sized to match the I.D. of the airfoil shaped compression strut extrusion. This is where the strut attachment bolt penetrates. The final part only weighs a couple of ounces yet it began as a 3" O.D. round bar weighing several pounds. It seems counter-intuitive to use such large material for such a small part, but it needed a much larger cone base to cover a 2" sq. tube because so much width is lost due to the ~45 degree mitre. I wanted to spread the compression footprint across the entire width of the tailboom tube to the side walls, rather than concentrate all the load at the midpoint of the top wall.

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                      • #71
                        The geometry gets real interesting where the airfoil compression strut meets the fitting at the tailboom. Allowing .090" separation at all points between strut and fitting meant the clearance notches would resemble an inverted Nike logo. Since this was 3D modeled I could extract a flat pattern to print and glue-wrap around the tube to get the exact shape. I used a vice and clamp to secure the motor section of a small router in midair where I could carefully slide the tube, rather than trying to keep the tool square with the part by hand. A couple of stainless brackets and wooden wedges allowed me to have a mechanical flat on the tube to keep it square and wobble-free while carving.

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                        • #72
                          While I'm at it, thought I'd share the axle inserts. These were completed some time ago while the forum was having issues.

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                          • #73
                            Making progress on landing gear. It was time to install the axle inserts shown in the previous post. The first photo shows how I secured the LG strut inside a square tube at both ends with wooden wedges on 2 adjacent sides. There wasn't really a good way to secure a round tube to the saw's miter feed with clamps alone. Not visible in the photo is a mechanical stop clamped to the saw's extendable top at the far end of the tube. This allowed cutting both LG struts exactly the same length without introducing measurement errors.

                            The 2nd photo shows the initial drilling. I used the same centering trick shown in post #58, with one additional "twist". The tube had already been drilled on the other end for the keel connection insert, and I wanted the new holes to line up exactly with the existing hole. I placed the shank of a long 1/4" drill bit through the existing hole that magnetically held a dial level (upper right in photo). This allowed the tube to be rotated until the bit was perfectly plumb. Since the drill press had already been plumbed and leveled, the two sets of holes were necessarily aligned.

                            The last photo shows the match-drilling of the axle insert. The astute may notice a change in vices. The heavier one in the last photo was required due to a slight load deflection noticed in the previous one which tended to shift the tube a couple thousandths during tightening. The tiny offset wasn't visible but could be heard as a scraping sound while doing a power-off test plunge of the bit. Also in the last photo you'll see a 1/4" center punch passing through the tube and insert at the first hole. The drill press has a small amount of runout which I didn't want throwing the insert out of rotation during the match drilling. The punch locked it in place. Surprisingly both inserts and tubes are interchangeable, with nearly identical bolt friction though I still have them designated left and right. I didn't expect such close tolerances. I could brag but it's more likely a happy accident, as Bob Ross used to say.

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                            • #74
                              Artistic little phuck ain't you? Looks great, very nice.
                              I personally would get rid of the sharp points, as to not catch rags or flesh while working on it and cleaning it.
                              Life,The leading cause of Death

                              Live and Learn--OR--Die and be an example

                              321.252.7705

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                              • #75
                                nice work

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