Diamond Demon Flashes New Skin In The Sun

David Millburn from down under (That’s Australia mate) shows off his freshly covered Ben Buckle Diamond Demon. Purchased in late 2013, she’f nearing the fledgling flight!

Ben Buckle Diamond Demon build by David Millburn, Australia.

Great color combination.

Hopefully he’ll fill us in on radio and power system. She’s looking great!

Ben Buckle Diamond Demon build by David Millburn, Australia.

Ben Buckle Diamond Demon build by David Millburn, Australia.

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Customer asks a good prop question with implications…..

Hi Dave,

Quick question about the APC props. I note that for multi-rotor the sizes seem to be with 4.5 pitch. Is there a reason why I should not use say, 9×6 with 9x6R for multi rotor craft?

Thanks
David

Answer:
Hovering props or props that produce best thrust in static air tend to be pitched about 1/2 of diameter or less. As you add more pitch, they can fly faster, but have less bite in static air. They can actually be stalled and have less lifting force until the prop gets to moving forward. This is also why props which are the same otherwise make more noise with lots of pitch. Initially they are stalled or partially stalled. So, if you need more prop than a 9-4 to apply the power to the air you have available in your system, you go to 10-4, not a 9-6. Certainly a 9-7 would be such a bad choice as to be worthless.

All this is considering the model is essentially hovering all the time. Even forward flight isn’t quite as forward as an airplane. Other types of flying and machines can have other considerations that make higher pitch (relative to diameter) correct but this is unlikely in all multi-rotors except maybe a racer.

What we call these props is 1/2 square. Meaning pitch is about 1/2 the diameter. A pattern aircraft or war bird might use a 3/4 square (like a 10-7 or 11-8) or even a square prop (like 12-12) because hovering is not a required and speed is more desirable. These setups are poor on hole shot, but once they get moving they really go.

Dave
Hi Dave,

Quick question about the APC props. I note that for multi-rotor the sizes seem to be with 4.5 pitch. Is there a reason why I should not use say, 9×6 with 9x6R for multi rotor craft?

Thanks
David

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Bill de Blasio to resign?

It’s only a mater of time in my view. The police are continuing to turn their backs on him. He has earned a complete disgust from those the public value as indispensable protectors. How can this stand? What we are seeing is how effective ostracism can be. And, all the while, traffic tickets are down 90%, the predation of the drug war has been reduced. Officers are under instruction to withhold revenue from arrests and ticketing except where absolutely necessary. This of course begs the question, what the hell where they doing before? The society of NY hasn’t fallen apart. Be aware of the important lessons being demonstrated by accident in New York City. This partial shutdown just like government shutdowns can’t go on for long. It won’t take long for the public to realize how unimportant and dispensable such a huge overbearing government complex is. They will bring this “strike” to an end soon. My prediction is with the resignation of de Blasio.

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Understanding Flush Aircraft Riveting

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Why Barrack Obama is making the right move on Cuba

I agree with President Obama on opening up with Cuba. Probably for very different reasons than why he is doing it. You might disagree and point out Che hated and killed black people and you’d be right. You might also point out all the firing squads and mass graves of Castro’s Socialist revolution. You’d be right. Many horrible things have been done in the name of “the greater good”. Whenever I hear the utterance of that term, it is always employed as justification of violence or threats of violence being used against a persons natural Liberty to peaceably make their own choices. It appeals to the worst element in mankind’s capacity to use violence and force to control others for the achievement ones own personal goals and objectives.

While the Castro’s, Che and many of their past and current actions are truly evil, what of the people that live in Cuba? Is our disgust, is the enemy of Liberty the people who are imprisoned by the Castro’s?

As a first principle, I regard all attempts to control and limit voluntary exchange as evil. If the people of Cuba wish to trade with the people of Florida or Texas or France or Alaska or Russia or whomever, why not? How do you or I gain a right to act as a 3rd party controller preventing two willing and peaceful people from trading? Simply stated, our embargo hasn’t kept one steak or lobster off the plates of the Castro’s. They live like kings off the people they farm in the name of the “greater good” regardless of our personal offense. I see no right, effectiveness or kindness in refusing an element of freedom to an oppressed prison population of a Socialist state.

As an aside, if they wish to be free from the slavery of their service to the Castro’s, it can only happen when they have something to be free for. It can only happen if exposure to glimpses of freedom and Liberty grows in them a desire to take care of business. By interacting with them, we can provide that encouragement and example.

No person has a right to control, limit or inhibit voluntary exchange between two other people. If we wish to be free, we must identify and reject those who claim a right to impose their choices on others by force.

Clearly, if you wish not to trade with Cuba or consume Cuban products or offer products to Cuba, I support you in your choice. I wouldn’t dream of using force to make you consume or provide services to anybody anywhere. I ask simply that you to consider conferring the same respect of personal Liberty to everyone.

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Spirit of Sam Power System Decoded

I’ve had a number of inquiries for an alternate Spirit of Sam power system. I worked out a system for Phil Pearce. He’s had a chance to do some run time and amp draw tests. Here are his comments thus far.

Phil Pearce Spirit of Sam Afterburner Setup

Phil Pearce Spirit of Sam Afterburner Setup

Good morning Dave. Here are a few picture of the little 5 oz Wren, built for the Spirit Of Sam event at the Society of Antique Modelers events. The rules call for the power battery be a single 160 mah lipo. The task is endurance, using the second best flight time of two flights. The motor you provided is an “Afterburner High Performance Brushless Motor. The number on the info. sheet says: MR-012-030-4000-1.5 I ended up using a GWS 9/7 prop. As the picture shows, the rear lipo is for radio power. The BEC is disabled. My procedure for maximum flight time is to hand launch with full power of about 1.5 amp draw, than establish a slight climb at minimal power of probably about 1 amp. I level out at about 200 feet and only use enough power to maintain altitude while looking for signs of lift. The motor will start slowing down at somewhere between 8 and 10 minutes with no thermal help. I must immediately start a landing approach while the prop is still spinning and plan on landing in about 15 seconds. Unfortunately a folding prop is not allowed. The drag on a stopped motor is dramatic on this small light model. I hope this is what you wanted. Thanks again for you help. Regards, Phil

P.S. If you have any advice on another prop, please advise. PP

Phil Pearce and his 5 ounce Wren Spirit of Sam competition model.

Phil Pearce and his 5 ounce Wren Spirit of Sam competition model.

Equipment is a 4000kv 12mm Afterburner with 1.5mm shaft. Running in a GWS LPS gearbox 4.8:1 ratio.

close up of gws lps gearbox with afterburner motor installed.

Close up of GWS LPS gearbox with Afterburner motor installed.

Links to parts supplied by Radical RC:
GWS LPS 5:1 “B” Pinion: GWGER002
GWS LPS 5:1 “B” Blue Spur Gear: GWLPS4B
GWS LPS 5:1 Blue Spur Gear: GWLPS4B
GWS LPS Ball Bearing Set: GWLPS2A
GWS LPS Gearbox Shaft: GWLPS6A
GWS LPS Gearbox Frame: GWLPS5A
Afterburner Motor (Take 1.5mm shaft option): MR-012-030-4000
Screws for AFterburner Motor: MR-SCREW-080-125-2
All parts needed are contained in the system linked below. Replace motor with 12mm Brushless Afterburner. Note, If you buy the brushed motor system to get all the parts, consider buying a pinion. A puller is needed to remove one from the included brushed motor and it can be ticklish. Some skill, minor tools and a drill press (or press of some sort) are required to install a pinion on LPS RXC OR RLC Drive take “B” gear ratio option: GWLPS-RXC or GWLPS-RLC
GWS LPS Gearbox Frame: GWLPS5A

side view motor and rx battery spirit of sam geared brushless power system

Side view motor and RX battery.

Note, the point of this blog post is to record what we did in a way that will last longer than my memory. If you want to do the same thing, all the links are provided. ;-)

Some thoughts that I have based on what I know thus far: An “A” ratio (less reduction) could be considered in order to reduce the pitch or perhaps the disk diameter. That might lead to a 9-4.7 or 9-5 or 8-6 being optimal. I’m tickled by the idea of a 4 or 5″ high rpm setup in order to try and get the model to glide with a stopped prop longer than Phil reports with 9″ props. Not being experienced in the competition, my thoughts might be completely off base here. The higher KV Afterburner motor should be avoided because the higher no-load current. Although it might be more efficient at wide open throttle, the minimum no-load current would kill you in cruise (partial throttle flight). So, the lesson is stick to the 4000kv motor. Anything you can do in this contest to utilize a low non-load current motor would probably be an advantage over most motors with higher no-load currents. The no-load current rating is one of the fixed parameters (motor constants) of every motor. Explaining it fully is beyond the scope of this article.

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Micro Stick Fleet Tryout

Gil Weiss from southeast PA sends a beautiful photo of his Micro Stick. Just test flown. Looks Great Gil!

Gil Weiss Micro Stick from South East PA.


Hi Dave,

Several years ago I built a Micro Stick. The kit went together very nicely. The little plane sat on a shelf until today. I enjoyed the last nice day of calm warm weather here in SE PA and test flew the plane. It was a real Hoot! Flew great and had an unbelievable roll rate. Landed fine. Other than add some more “expo”, no changes were required. I will keep this plane in my active fleet from here on out.

Regards, Gil Weiss

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John Harper’s Creamsicle Stick 600 Part 4

Hi Dave…
The Stick 600 got its maiden flight today. Test pilot Doug says it’s a real sweetheart, and had it alternating between floating and zooming. My watt meter says I’m getting around 248-250 watts with the 11×5.5 prop, and we had about 70% of the 3s 2200 battery left after a 6-7 minute flight. Due to my complete imeptness attaching photographs, Susie is going to send you some pics and short videos. As you can see from the takeoff there’s no shortage of power. Nice plane!
Thanks, John

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Stick 600 – Creamsicle Part 3

creamsicle comparison stick 600

How does she stack up?

John gives us a comparison photo between his Stick 600 and a Great Planes ElectroStick. His comments: “Here’s a comparison with Test Pilot Doug’s Great Planes Electrostick. It’s about 5 lb. with a .32 Rimfire. It flies nice but not very slow.”

Front 3/4 View of John Harpers Stick 600 Creamsicle

Front 3/4 view.

John Says: “Here’s a front quarter view. All pictures by my lovely and talented wife Susie, who is a damn fine pilot in her own right.”

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Stick 600 – Creamsicle Part 2

stick 600 creamsicle

John Harpers Stick 600, the business end.

To: John Harper: (July 31, 2014)

I made a mistake in that last email. I calculated the Power 15 from Eflight. If you used a Power 10 then it’s 36 amps, 11×5.5 prop, 2357 feet per minute at 83 degrees. Should be very impressive. That is a much smaller motor and battery than my lowest recommendation. I think your test flight is going to prove to me that I could have recommended something even smaller than I did.

I think you’ll end up around 405 watts if you meter it. You may be using a different motor than the E-Flight. I’m just guessing. Hope you can balance it. The normal motor on the small end of 3S that I recommend is about 8 ounces hanging out in front of the firewall. You’re only 4.3 ounces.

It should be a barrel of fun. You’r ship will do all that mine will do but at 1/2 pound lighter, it will be cable of doing them even slower. I’m wondering if you’ll have to add a touch of throttle to keep the glide from getting uncomfortably slow? That’s the only thing I would watch out for. It’s capable of descending under control in a nose high probably 45 degree angle of descent. But, you need a little speed to find a flair at the end. ;-) You’ll be amazed at how low and slow you can trust this airplane. If you’ve been flying a bunch of overweight models, this is really going to be different for you.

Dave

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