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Old Nov 09, 2012, 09:27 PM
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Update

Change number 1,001. I momentary set aside the Computer Fan conversion and opted for the tradition motor/prop configuration and will build ducts for them. The duct shown is for illustration, I will build the duct from aluminum sheeting. Here are a few pictures of the work in process.
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Old Nov 10, 2012, 07:28 AM
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Doak VZ-4 VTOL (1 min 19 sec)
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Old Nov 13, 2012, 12:46 PM
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I had to settle for what I could purchase from Home depot and able to fabricate in my shop. Found this 10" concrete form that I am able to cut fairly easy and the weight is not bad. I cut the tube to 2.5" for this version and can see that I am able cut it to 2" for future versions saving on weight. One thing about my builds, I build first being mindful of weight, but it is not the highest of priority. Once I have a flyable aircraft, them I start looking for ways to reduce the weight.
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Old Nov 14, 2012, 02:23 PM
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She is starting to come together.
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Old Nov 15, 2012, 01:21 PM
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Ok, she is ready for the electronics installation. Most if not all of the controls (Pitch, Roll & Yaw) will be handled via Thrust vectoring however, I installed some oversize flaps in hopes of lowing the Stall speeds of this wing. The Wing itself has a very high lift airfoil so we will see if these flaps are necessary.

I have two controllers that I am considering, one a Flip with a MPU6050 and a ATMega2560 also with a MPU6050, I have not made up my mind yet as to which one.
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Old Nov 15, 2012, 03:22 PM
Jet's are cool!
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Looks pretty cool Rimshot, cant wait to see it fly!
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Old Nov 24, 2012, 11:06 AM
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Because I have had exceptionally good success with the variable pitch tail rotor system built for Black Mollie, I am strongly considering adding one to this build to simplify development. Once the transitional procedures are in place, the tail can be replaced. I am very happy that I started building parts interchangeable between all of my builds.

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Old Nov 24, 2012, 03:32 PM
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lookin' good Rev ..... always loved the vz-4 ..Built a moc-up one time , and had two lift fans , like this one , controlled roll and yaw , like a bi , but the pitch was controlled via .. a small motor and prop mounted inside the fusalage , blowing out the back , with a vane on a gyro.....worked , but is was old school with gyros...

carry on--- soldier of vtols'

Terry
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Old Nov 24, 2012, 05:56 PM
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Update

I have the servos and mounting brackets installed, now I need to come up with a push rod and control horns.
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Old Nov 27, 2012, 01:47 PM
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I have a new appreciation for all of the coat hangers once discarded. I purchased a 2-56 threader and have utilizing coat hangers for push rods ever since. The servos used here are only for the flaps and will not see much usage however, in the future, I hope to replace them with some metal gear servos. I am going to start flight testing using one of Whitespy's flip board and later upgrade to to a ATMEGA2560 or greater, want to make sure the concept is good before investing to much resource.
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Old Nov 27, 2012, 02:03 PM
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BTW, here is a look at the airfoil.
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Old Nov 28, 2012, 04:14 PM
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I now have one servo assembly nearly finished, need to shorten the push rod a few more turns. My best guess at this time is, I will only need 120 degrees max travel on these servos. The MG995 will do that easily and with a servo extender or modifications to the WMC, they will travel a full 180 degrees. At present, I see no need for that much travel because I want to maintain some downward thrust to help ease the wing loading. I made the decision to use the 5000 mah battery and that puppy weighs in at 480 grams.

Because of the tube size, I am limited to a 10" prop diameter, the ones shown are 9" with a little more tip clearance than I would like. Figured, I would get all of the bugs worked out first, then add the 10" pops later for maximum efficiency.
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Old Dec 01, 2012, 02:26 PM
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I had to move the Wing assemble backwards about 1.5" and the nose gear forward about 1.0" to balance the copter, now I am able to use the smaller 2200 mah batteries. Even by my own standards, she's becoming a little to heavy and the motors presently used, just will not generate enough thrust to lift her. I ordered some magnet wire and will rewire these RCTimer 750kv motors to 1500kv. At that time, I will switch to the larger 5000 mah battery.

Now it is a matter of cleanup, making modifications to the WiiCopter Firmware for the flaps and titling the rotors. We should be able to start flight testing maybe as soon as next week.

I used the V-22 model in the RealFlight Simulator to run simulations of a rolling take-off with the rotors tilted at 50, 60 and 75 degrees, lets just say, I will be one happy hobbyist when this build is complete.
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Old Dec 04, 2012, 01:38 PM
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Rather interesting I come across this thread now since I am in the middle of my own propeller/ducted design build.

Rimshotcopter, I hope you dont mind if I add a few photos and description of what I am doing...

So.....I am building the tri version of the terminator Hunter-killer(A8M heavy assault)

First pic is what I trying to create. The rest are what Ive done and or parts being used.
I bought some 5 gal buckets from Home Depot and have installed Rimfire .60 size 650kv motors with 11x7 3 blade MAS props. The power is 6s.
The two forward ducts will be tilted forward/aft, but only by about 15-25 degrees. They will be able to move opposite directions for stability...yaw control along with tail unit that can tilt side to side as well as forward and back.

The buckets will be mounted to the frame of the vehicle using high strength aluminum servo blocks from servocity that are ball-bearing supported. This takes the strain of the weight OFF of the servo and the entire fan unit can be directly mounted to the servo/servoblock with no pushrod or control arm.

I do not know total weight nor am I close to having an idea....but probably around 9 to 10 pounds. The total size of the vehicle will be roughly 8 feet wide and similar length long. Because of the size of the vehicle, if the 3 duct/fan rotors is not enough to lift it, there is plenty of space in the wing/pylon areas to add in additional thrust producers and hide them.

I have also setup the mounting in the buckets so I can add motors/props upside down from the main installed motors if needed. See photos.

The 11x7x3 and 10x7x3 size props I am using have both pusher/puller available.

Also...this vid here shows an example of a much smaller HK done using 55mm GWS ducted fans:
DIY 3roter (EDF ver.) Rev.3 "Hunter-Killer" by あんきもさん (3 min 29 sec)
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Old Dec 04, 2012, 02:04 PM
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Welcome kahloq and no, I do not mind at all. In fact, I am excite about the company.

I also had looked at using a plastic bucket and may revisit that idea later because it would allow for larger props. Your last picture with the dual motors is very interesting and I also had considered that option. jy0933 made an argument that the second prop "either the lower prop cant get enough air or the top prop get dragging faster due to the demand of more air" which sounded very logical to me, so I set the idea aside. Too many other issues to address. I love how you have your motor support and that servo assemble is my dream!! Would love to purchase a pair of them.

Yes, Please join the party.
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