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The Atom Special


Richard Harris
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My blades are repaired and now have a pronounced sharp LE very similar to Terry W's diagram.

Now I had an Ah Haa moment when reading your reply. Thank-you Frank! I couldn't get 0.8mm FG sheet either so I used 1.0mm approx also. My flight symptoms sound just like yours and Steve J's experiment was revealing also.

I'm learning the hard way.

So Steve you suggest that I could make some 0.8mm sheet. I would like to try. How do you suggest it could be done. I have all materials to hand, glass cloth and west systems epoxy.

It seems the flexibility of the plate is the key so Terry's Idea using the test rig may be very useful too.

Thank you all. My enthusiasm has returned. Cheers

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If 1mm thick FG plate is used there is no reason why my triangular plate can't be increased in size, adding an extra 30mm to the diameter should work I would think.

If I had some 1mm thick sheet I would experiment and get the correct dimensions for you, unfortunately I dont so I can only guess.

Dont give up

Rich

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Hi Rich,

Thanks for the reply about the plate thickness. I'm reading between the lines and assuming that the amount of flex is the key to the blades self adjusting their pitch to the varying load during rotation (advancing or receding) .

So my question before I embark on an experiment, is there any way to measure the amount of flex required of the plate? If it's just emperical, how do I know when I have a plate that will work with a specific set of blades (as they are made differently by various persons and not by a machine)? Do we look for a certain upward curve when the auto- gyro is suspended buy the rotor tips for instance? If

Any suggestions would be welcome and as I have a couple of weeks to wait on HK I will try it out and report back

Cheers D

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  • 1 month later...

Hello,

Sorry I've been a bit quiet due to having a testing session about 4 weeks ago and my Atom coming to grief and suffering minor damage. Repairs done, I had to wait for another opportunity. Time to reflect. A little more left rotor (aileron) and more forward rotor (elevator) trim was required. Remember I now have the correct 0.8 mm rotor plate.

Well today was it. And It all came together!!!! spin up good. I jogged along with it as it spun up so she didn't get to far away.

Then lift off was pretty text book as in other videos. Not easy to fly but then no drama once I settled in. I had 3 flights of about 4 minutes each. Boy am I stoked. It's been a long time reaching success.

Thanks Rich. I'm even thinking that my Panther is repairable and I might have another go with it.

Cheers D

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Dete,

Congratulations thumbs up your patience has paid off, try and get plenty of practice now that you have your Atom is sorted. I have said it a 100 times but it is one of the best pieces of advice I can give, keep it in close and get used to flying this way.

On another note I have been fully testing a new (revised older design) model with excellent results, I have passed on my drawings etc to David and will be keeping my fingers crossed it makes the grade for publication wink 2

 

Keep up the good work

 

Rich

 

Edited By Richard Harris on 16/09/2015 21:05:50

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  • 2 weeks later...

Hi all!

After 9 months of contemplating, I have finally decided to take the plunge. I am currently scratch building a Piper Pawnee but after some frustrations I needed to get my mind off it and I think the Atom will be an awesome challenge. Quick question though... Is there any special setup needed for your Tx? Do you setup a fixed wing model or a heli model?

Kind regards and happy landings

Bossie

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After four "warm up" flights with my Crane Fly I decided to give the Atom a go. The first attempt at ROG resulted in a roll over to the left (not enough rotor speed?). A hand launch resulted in a 60 degree climb and without the presence of mind to throttle back a crash to earth but only with damage to a bent motor shaft. I am using AJ blades with 0.4mm shim so think I will try 0.8mm next time, hoping for less lift with faster speed up. hang angle and throws seem correct.

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Yep roll left on take off sounds like classic insufficient rotor speed at lift off. If up to speed just power should give a smooth lift off.

High climb rate could be too much lift, my Atom lept into air at 60 deg with 0.4mm shims. Increase them to 0.8mm and perfect. Slightly more shim will also help faster spin up, maybe helping take off

Keep at it and you will get there, just try to remember if it climbs, reduce power

Good luck, Steve

Edited By Steve Jones 2 on 28/09/2015 20:48:45

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Hi guys.

Hope you are all doing well. Is there any other option for the 0.8mm triangle for the head? I am realy struggling to get hold of a sheet like that over here in SA. If I can just get that sorted together with the blades. I have never attempted to make my own blades so this should be interresting. Unfortunately with our wonderfully strong Rand ordering blades from AJs becomes quite expensive.

Happy landings

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Hendi,

If you are struggling to get hold of fibre glass sheet you could always replace the clear brittle plastic hinge sheet that comes with the HK head. You will need to find some polypropylene sheet of around the same thickness, generally identified with three P's in a triangle.

As for the blades they are easier to make than most think.

Rich

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Hi Hendi,

The blades are not hard to make. I have pictures on page 73. There is no need to use 2 x 1/4" hard wood on the leading edge. I used poplar and spruce as that is what I had. my blades are a bit heavy but it doesn't affect the flying. There is more info on the Panther forum.

The FG plate 0.8mm was critical to get mine to fly well. It was unflyable with 1.0mm FG and was transformed by the thinner plate and is now 'fairly easy' to fly but requires constant attention during flight.

I got mine from Hobby King in 10 days to Australia at the cheapest postage rate. Yes Our Dollar is crook too and things are 30% dearer. It was worth it! ( I find a link later)

I think I took the hard road but it was worth it. The Atom comes on every flying outing now.

For what it's worth, Cheers Dete

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Hendi,

I hope you manage to get on with your build this weekend, work does get in the way sometimessad

It has now been 14 months since this model was published (where did that time go!), I have been busy building and testing away and next month will see another freebie autogyro plan in RCM&E wink 2 This one is a cracking flyer using all the hardware as the Atom but a lighter loaded model.

I will start a thread in due course, need to get on with some house renovation work first before the cold weather sets in!

Rich

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I'm glad to report success on a cold and windy day by increasing the blade shims to 0.8mm. Faster spin up so ROG with no problems, still needs a bit more down and left trim but very pleased. Saving it now until calmer weather when I will also take the two blade version out. Thanks to Rich Harris and look forward to the next one.

John

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It was a wind free day at our flying site today so I thought it was time to bite the bullet and try to fly my atom!

After numerous attempts I did manage to get airborne but it was not what could be called controlled.

Anyway the last flight ended with a broken mast and one tail fin so its back to the workshop.

Haven't had so much fun trying to fly a model ever! Any tips regarding exponential settings Richard? I dialled in 40% after the first hops but the next hops seemed to be less controllable. The Atom zoomed up on the first attempts so I trimmed the head down, and I was able to make the model hop, but I was never comfortable with it.

Would nose weight help?

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  • 1 month later...

We are two experienced model aviators who built respectively Atom autogyro. One with AJ-blade and the other with home-made blade.
We have closely followed the setting of angles, rudder travel and center of gravity according to the construction manual. We also checked the radio range control.

At the start, we have always been sure that the rotor come up at the right speed, "whistling" sound.
So far everything is OK but once in the air the models is out of control (same for both models).

If I compare with a fixwing plane it is, as if the center of gravity is too far back and too much rudder travel!?
You have to constantly try to compensate for the wild behavior Atom does in the air.
After many attempts, which always made in low or no wind, remains the problem.
What can it depend on?

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Hi there, that's the challenge of these, just because people have flown aircraft or helis it is not automatic they can handle these

The Atom flies really well, both mine do straight away but as its small it's quite lively if over controlled...

Make sure the hang angle is about 16 degrees, a little more is ok. Set the head at about 6 degrees back then the tail is flat...head tilt should also he's tightly to the left when viewed from rear.

Set rates on your transmitter and I like about 25% expo... Personal choice.

Get a day with light winds then try some test hops, building up speed and power - but you will not need much. Mine take off on less than half speed, it's not ground speed which is important, like fixed wing, it's rotor speed.... That's where most go wrong if they already fly.

Once in the air keep speed steady and do left turns but not too far away. It's a small model and so is easy to get confused if too far away. If it climbs too much try using throttle , not forward stick as this kill rotor speed

Good luck, keep at it and with patience you will get there..

Steve

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