Steve Jones 2 Posted March 10, 2015 Share Posted March 10, 2015 No problem Rich, use any of my models pics Steve Quote Link to comment Share on other sites More sharing options...
David P Williams Posted March 10, 2015 Share Posted March 10, 2015 ....and you're very welcome to use any of mine too Rich. Quote Link to comment Share on other sites More sharing options...
Terry Whiting 1 Posted March 11, 2015 Share Posted March 11, 2015 Rich, Photos go ahead, I regard it as a complement Quote Link to comment Share on other sites More sharing options...
Max Z Posted March 11, 2015 Share Posted March 11, 2015 Rich, I am happy to "release" my photo's for your blog. Max. Quote Link to comment Share on other sites More sharing options...
Kevin Flynn 1 Posted March 11, 2015 Share Posted March 11, 2015 Rich you are welcome to use any of my photos, thanks again for another winner Kevin Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted March 11, 2015 Author Share Posted March 11, 2015 Cheers Gents, I have added the completed Atom photos that I can find which totals 33 models, these are located HERE. If I have missed any then please let me know and I will add them. Rich Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 13, 2015 Share Posted March 13, 2015 My brains got stuck in a loop bit of reassurance please 1/64 is o.k for the shim (0.4mm) ? John Quote Link to comment Share on other sites More sharing options...
Terry Whiting 1 Posted March 13, 2015 Share Posted March 13, 2015 Hi John, There's no problem using a strip of 1/64" , after all it's still doing same job giving the blade neg incidence.. just make sure it's positioned at the recommended measurement. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 13, 2015 Share Posted March 13, 2015 Ta Terry John Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted March 13, 2015 Share Posted March 13, 2015 Nice Flash Webb site you have there Richard . Steve Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted March 13, 2015 Author Share Posted March 13, 2015 John, 0.4mm is close enough to 1/64" for our needs, this is the correct thickness for the shim though many are using 1/32" (0.8mm) to good effect. Thanks Steve, No where near finished as you can see, just adding those photos took me a couple of hours! Rich Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted March 13, 2015 Share Posted March 13, 2015 Both mine run 0.8mm shims Steve Quote Link to comment Share on other sites More sharing options...
Grasshopper Posted March 14, 2015 Share Posted March 14, 2015 Hi Steve/Rich, I an using AJ blades with .4mm shims and so far my flights have been short - and not too sweet! The spin up seems good but stability in the air is dire. Hang angle is 15deg and throws have been very carefully checked. Could changing to .8mm shims be worth a try? Peter Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted March 14, 2015 Share Posted March 14, 2015 Peter, I am not sure about AJ blades as I always make my own. They do however have a good word from many in all their sizes so don't understand your comment on stability at the present. Could you expand what you mean to give us more of a clue - in what way and when etc Steve Edited By Steve Jones 2 on 14/03/2015 09:43:43 Quote Link to comment Share on other sites More sharing options...
Gyrocopter Posted March 14, 2015 Share Posted March 14, 2015 Here's Mick with his new Atom at Old Warden, we flew it last week and like all atoms........ it flew very well. He is going to give it more rearward tilt travel to help with the spin up on calmer days. I was most impressed with the home made head, nice woirk. Chas Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted March 14, 2015 Share Posted March 14, 2015 Posted by Grasshopper on 14/03/2015 08:35:42: Hi Steve/Rich, I an using AJ blades with .4mm shims and so far my flights have been short - and not too sweet! The spin up seems good but stability in the air is dire. Hang angle is 15deg and throws have been very carefully checked. Could changing to .8mm shims be worth a try? Peter Hi Peter I f your control throws are set as recommended , could your description of unstable flight refer to an apparent over sensitive roll response? If so a lower shim thickness will result in more lift which in turn can increase the following rate to the point were roll response is hard to manage. Reducing control throws further and or adding expo will probably not help but adding tip weights will so the question is .....do the blades have tip weights fitted? Increasing the shims to 0.8mm may also make things feel better ,but if spin up is good it may be preferable to maintain high lift and add tip weights if not already fitted. Should you already have tip weights then a more detailed account of the the flight characteristics would help. Regards Tom. Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted March 14, 2015 Share Posted March 14, 2015 ,Lovely model and great to see another air lurks to add to the growing fleet. Really like the home made head, great job Steve Quote Link to comment Share on other sites More sharing options...
Graham L Posted March 14, 2015 Share Posted March 14, 2015 Hi I am using aj blades with 0.4 shims and no additional weight and my atom spins up and flies just fine. Tip to bolt hole at 425mm and total length 450mm. Have hang of 16 degrees , 5 degrees of back tilt and left trim of 3.5 degrees. Graham Quote Link to comment Share on other sites More sharing options...
Grasshopper Posted March 15, 2015 Share Posted March 15, 2015 Graham, thanks for the information. Your idle tilt is 3.5 degrees left and (I thnk) idle ptch is 5 degrees back? My mate Sam and myself are runnung as follows hang angle 16 deg idle left tilt 1 deg idle pitch 0 deg, Sams Atom is not on AJ blades and he has had several good flights but thinks it needs more 'sorting' before it will be good. My AJ blades are 460 long with bolt hole 10mm in from root end. I note that youir bolt hole is 25mm in. Might this be a problem on mine? I am off to make some more tests in 30 minutes and will report back. Peter. Edited By Grasshopper on 15/03/2015 08:28:13 Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted March 15, 2015 Author Share Posted March 15, 2015 Chas, Nice Atom Mick has made there, I do like the head work. Is it an optical illusion or is his Atom a little bigger? Peter, I think 'Stability in the air' needs to be a bit more defined so as to pin point the issue. Could it be that it is just out of trim? As I have have mentioned before I find it best to hop the model and trim in between if needed until a hop with virtually no input from the pilot is needed. If your blades are spinning up and it is taking to the air, I very much doubt that the issue is with the AJ's, to date I have not heard any stories of bad AJ blades. Good luck with your flying today, we expect a full flight report later on Rich Quote Link to comment Share on other sites More sharing options...
Gyrocopter Posted March 15, 2015 Share Posted March 15, 2015 Rich, No, its normal size I guess Mick is just holding it close to the camera. Quote Link to comment Share on other sites More sharing options...
Graham L Posted March 15, 2015 Share Posted March 15, 2015 Peter My head tilt back is 5 degrees measured using the tailplane as the 0 degreedatum line. In other words if you put a pitch gauge on the tailplane and prop the model up until it reads 0 degrees you can then measure the tilt back by putting the gauge on the head plate and adjust till you get 5 degrees. That is a good starting point and any further a adjustment can be done when it flies. Side tilt is measured looking at the model from the rear and I started at 2 degrees left and had to increase to 3.5 degrees to trim it out properly and stop it banking right. Your blades should be fine with the measurements you have and should not affect stability . Agree with the other guys comments that without knowing exactly what it is doing when you say it is unstable it is difficult to give advice on what to adjust. Have flown 3 atoms and seen another 4 or 5 and all have flown well off the board with relatively minor trimming Graham Quote Link to comment Share on other sites More sharing options...
Grasshopper Posted March 16, 2015 Share Posted March 16, 2015 Graham, Rich et al, thanks for your input. I was unable to fly yesterday as it was raining, windy and cold. My visit to the club was not in vain as one of the chaps said he had video of one of my short lights. I have now looked at this many times and clearly the spin up is good but take-off occured probably before there was much lift with a resulting rapid bank left (stall?) and into the deck. Other tests gave the same result. I also noted that after the 'take off' applying full right roll to try to compensate did nothing at all, probably I guess as the blade speed/thrust was insufficient. Over to Grahams nice clear email: I have just checked my pitch angle as he detailed and with the tail boom horizontal the neutral pitch is 6 deg to the rear which should be near enough? The pitch throws are +- 6 deg. The roll neutral is 1 degree left so less than Grahams and the roll throws are +-12 from neutral. In my humble opinion then my initial attempts were doomed to failure as take off occured before the head speed was sufficient. What do we think? Peter Edited By Grasshopper on 16/03/2015 09:47:46 Edited By Grasshopper on 16/03/2015 09:48:06 Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted March 16, 2015 Share Posted March 16, 2015 Peter, Clue for me if my rotors are spinning fast enough at the point of take off is if just addition of a little more power creates the lift off. If 'lift off' is encouraged by the application of rear tilt (a bit like elevator on a fixed wing), it the head is not upto flying speed the the dreated 'snap left' normally happens. If your lucky sometime it can be caught, if your not then time to get the glue out. So now I try and spin up the rotor and take off with only power at the point of rotation, if it wont your not ready.....when you you get it right its really rewarding. The message I learn the hard way to start is - Dont try and force the takeoff. Good luck Quote Link to comment Share on other sites More sharing options...
Max Z Posted March 16, 2015 Share Posted March 16, 2015 I can support what Steve is saying. When there is a bit of wind, I leave the motor off, tilt the head fully backwards, wait until the rotor is more or less up to operating rpm, tilt back to neutral and apply power. Then wait until your AG takes off by itself. In a low wind situation I sometimes apply a little power early on to move forward slowly and help the rotor spin up, but always return to neutral pitch before opening the throttle fully. The trick is to recognize "operating rpm", which comes with experience only........ I have had situations where there was wind, and I left the backwards tilt for too long, resulting in taking off and flipping over from stationary . Max. Edited By Max Z on 16/03/2015 14:43:43 Quote Link to comment Share on other sites More sharing options...
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