Stephen Jones Posted January 3, 2015 Share Posted January 3, 2015 Hi , What is the average AuW builders are getting , Mine is 630 Grams What size prop are you using , I have a 10x5 What size battery and C rating are you using And finally what are you're static thrust readings . I have gone through all my batteries ranging from 3s 2200 20c - 3s 2200 25c , 3s 1300 20c - 3s 1300 25c . So far my best performance is from a 3s 1300 20c lipo that is pulling 11.5 amps . Steve Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted January 3, 2015 Share Posted January 3, 2015 Also any chance we can have a look at those final radio installments as it seems to be very cramped in there . Steve Quote Link to comment Share on other sites More sharing options...
Phil Winks Posted January 3, 2015 Share Posted January 3, 2015 Posted by Stephen Jones on 03/01/2015 19:05:47: Hi , What is the average AuW builders are getting , Mine is 630 Grams What size prop are you using , I have a 10x5 What size battery and C rating are you using And finally what are you're static thrust readings . I have gone through all my batteries ranging from 3s 2200 20c - 3s 2200 25c , 3s 1300 20c - 3s 1300 25c . So far my best performance is from a 3s 1300 20c lipo that is pulling 11.5 amps . Steve Steve that 11.5 amps on a 3s equates to approx 127.65 Watts which is fine for a 630g model of this type you should be looking for approx 80 to 100W per 450g any more and she'll be ballistic your AUW seems about average from what I've seen others posting I've not got to fitting the electronics but I also expect it to be close fitting but then my ESC is a little bigger than Richards Edited By Phil Winks on 03/01/2015 19:21:39 Edited By Phil Winks on 03/01/2015 19:23:31 Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted January 3, 2015 Share Posted January 3, 2015 Thank,s Phil, So you think i should be good to go as is . Steve Quote Link to comment Share on other sites More sharing options...
Phil Winks Posted January 3, 2015 Share Posted January 3, 2015 Posted by Stephen Jones on 03/01/2015 19:22:08: Thank,s Phil, So you think i should be good to go as is . Steve Absolutely Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted January 3, 2015 Share Posted January 3, 2015 Posted by Phil Winks on 03/01/2015 19:24:28: Posted by Stephen Jones on 03/01/2015 19:22:08: Thank,s Phil, So you think i should be good to go as is . Steve Absolutely Ta ,will see what the weather brings us tomorrow . Quote Link to comment Share on other sites More sharing options...
Phil Winks Posted January 3, 2015 Share Posted January 3, 2015 No idea what the weather in Bury's going to be like but here in the SW its looking like a good if not dull and chilly flying day Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted January 3, 2015 Share Posted January 3, 2015 Martin, build looks good and plenty of work in that Head good luck with the flight tests. Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted January 4, 2015 Share Posted January 4, 2015 Martin: I have found the only way to know if things will work Is to give them a try.. I think everything looks fine. With that bing said I will add my 2 cents. Only one thing I would change befor your maiden, on the motor the gap between the motor and the prop nut is too much the first time the prop hits the ground the shaft will bend and you will be calling it a day. AND YOU WILL HIT THE GROUND. I would measure the gap and cut that much off the end of the shaft so the prop nut is right up tight to the motor body. Trust me been there, have the bent shafts to show for it. Good luck mate. Bill Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 Thanks Bill, you are of course quite right about the long shaft but when I tried to remove and reverse it in order to fit the direct bolt on adaptor my expensive hex driver snapped off in the grub screw . I shall wait till I bend it before cutting the end off completely. Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted January 4, 2015 Share Posted January 4, 2015 Well this morning the weather is fine , Blue skies , calm Batteries all charged up . Checked the programming of my Field Force 7 Transmitter , Hmmm why is that servo doing that , re checked the programming , swapped the servo to a different channel . Ok this is not playing ball lets try a different model memory that i know is ok , Still one of my servos is acting up . Ok i thought lets try a model that i know is ok and i powered up My Sipa 200 the Camouflaged one , and one of those servos start acting up . Conclusion my Transmitter is at fault . So much for my Maiden today, Steve Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted January 4, 2015 Author Share Posted January 4, 2015 Stephen, Better to find out on the ground before the maiden!..talking of the Sipa, whatever happened to the plan submission to the mag? its cracking little model. Rich Quote Link to comment Share on other sites More sharing options...
Stephen Jones Posted January 4, 2015 Share Posted January 4, 2015 Hi Richard , Yes i always check my models before i fly as it is all too easy to have the wrong model memory set . But this seems to be a fault with channel 1 . My Sipa 200 , The plans have been sent in both PDF form and CAD form . And i have done a write up to go with it . Which Graham said he was pleased with . My last Email from Graham simply said Speak soon . Steve Quote Link to comment Share on other sites More sharing options...
Nigel Banham Posted January 4, 2015 Share Posted January 4, 2015 Hi Richard, Advice please!!!!! I'm the man with the ASP.12 i.c. engine on the front of my Atom. I ran in the engine and got it to 15k with a 7x4 prop before switching to an 8x4 for the maiden.....so lots of urge at the front. I tried to fly before Christmas - nice bright windless day - and found that despite plenty of forward speed, the rotors were not (rotating) , so no lift. Took it home and increased the rotor incidence, ie tilted them back slightly more than the 90 degree angle with the mast. Tried again this morning but it made no difference - still the same result. Two questions. My rotors are set up to spin anti-clockwise, as yours appeared to be - some autogyros go the other way - does this make any difference? Secondly, should I attempt to spin the rotors as fast as possible at the beginning of the take off run? Well - at least it provided entertainment to my shivering club mates at our bright but very frosty fly-in! Many thanks, Nigel Banham Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 More ramblings. As I said I am not entirely happy with my rotor blades so have made a new set ready for covering. These only took a few hours and have been finely balanced span wise and against each other using PVA. I have incorporated 1/4sq spruce and piano wire to weight the LE and add strength. The scales used are cheap on ebay but don`t get caught walking down the street with them or you are likely to get your collar felt Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 Everything out of sequence because this site has gone silly again! Click on the bottom right as usual and everything turns blue then disappears. Quote Link to comment Share on other sites More sharing options...
Max Z Posted January 4, 2015 Share Posted January 4, 2015 Hi Martin, I had a look at the pictures you posted earlier, and with my limited experience (one Atom built and successfully flown) I wonder about some aspects of your rotor head. First thing is that I am missing any visible shimming to ensure negative blade incidence. Have you allowed for it in another way? Secondly the blade pivot bolts seem to be further inward than as per Richard's design, leaving a rather small gap between blade root and central rotor holding plate. It was widely discussed before and should be about 14 mm. Your setup seems to be very stiff, aggravated by the larger holding plate than the standard HK item. Max. Edited By Max Z on 04/01/2015 17:58:56 Quote Link to comment Share on other sites More sharing options...
Terry Whiting 1 Posted January 4, 2015 Share Posted January 4, 2015 Martin, Following Max's observations I thought your blades leading edges looked rather rounded but then it may be a trick of the light and the photo. If they are rounded this is the type of profile they should be... Terry Edited By Terry Whiting 1 on 04/01/2015 18:28:53 Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 Hi Max, thanks for your observations. The head and blades are from a CFL and built to that spec. with 4mm shims fitted. There is plenty of flex and they spin up OK. I have nearly finished covering the blades detailed above and shall fit them soon. I shied away from the HK head because of unavailability and the fact that I already have two made. Also, it needs so many mods that it was just as easy to make my own. The proof of the pud. as they say ---. Wish me luck. Martin Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 Hi Terry, I agree. The new blades are to that profile. Martin Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 Some pics of the new blade profile. Quote Link to comment Share on other sites More sharing options...
Steve Jones 2 Posted January 4, 2015 Share Posted January 4, 2015 Hi Martin, Both my Atoms use blades without weights - 1/4 spruce leading edge then the rest medium stiffness balsa. Your profile looks Ok, mine are just done by eye with razor plane and sanding block lengthwise. As for shims I started with 0.4mm on the first one and this generated a reasonable spin up but far too much lift!! Take off was at half throttle at about 60 degrees !! Rich suggested more shim to kill the lift so i added another 0.4mm ply strip to take the total to 0.8mm. This time the take off was perfect with a faster spin up. On the second Atom, my yellow one I went straight for 0.8mm shims and it flies great. As for the head angle its just rear of 90 degrees to the mast. If I set the tail booms level on the bench the head forward arm measures 6 degrees... Hope this helps Steve Quote Link to comment Share on other sites More sharing options...
Caveman Posted January 4, 2015 Share Posted January 4, 2015 Hi guys, I have a query - I notice in Max Z's posting above he mentions that the gap between the blade root and the central rotor head should be 14mm, in order, I think, to allow sufficient flexing of the mounting plate. I have built mine as per Richard's instructions in RCME and my gap is only 4mm! According to Richard's write up, the blade mounting hole should be 430mm from tip of the blade, which is 450mm long, hence the distance from mounting hole to blade root is 20mm, and leaves a 4mm gap to the rotorhead. If the gap should be 14mm then I will need to remove 10mm from the blade root. Have I misunderstood something, or are the instruction wrong? Incidentally, the blades I received from AJ were actually 461mm long! Therefore my mounting holes are 441mm from the tip to compensate. Can you also confirm that, for the AJ blades, the shim at the back edge of the blades root should be 4mm thick. Your advice would be appreciated, to ensure (haha) a perfect maiden flight! Cheers GDB Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 4, 2015 Share Posted January 4, 2015 New blades now finished and fitted. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted January 5, 2015 Author Share Posted January 5, 2015 Posted by Nigel Banham on 04/01/2015 16:00:33: Hi Richard, Advice please!!!!! I'm the man with the ASP.12 i.c. engine on the front of my Atom. I ran in the engine and got it to 15k with a 7x4 prop before switching to an 8x4 for the maiden.....so lots of urge at the front. I tried to fly before Christmas - nice bright windless day - and found that despite plenty of forward speed, the rotors were not (rotating) , so no lift. Took it home and increased the rotor incidence, ie tilted them back slightly more than the 90 degree angle with the mast. Tried again this morning but it made no difference - still the same result. Two questions. My rotors are set up to spin anti-clockwise, as yours appeared to be - some autogyros go the other way - does this make any difference? Secondly, should I attempt to spin the rotors as fast as possible at the beginning of the take off run? Nigel, You are correct, the rotors should spin in an anti-clockwise rotation (looking from above), if they did spin opposite then the recommended trim settings (in roll) would be opposite. Yes, give the rotors a good spin bevore attemting your take off run. Just to double check that you have good spin up you can hold the model above your head so that the rotors are tipped back into wind(remember to have your radio switched on). They should spin up pretty quickly in a breeze, if no breeze is about then a brisk walk into wind should get them going. You will hear them whistle as they get up to speed with a strongish pull from the lift. If they dont do this then you have an issue somewhere, if this is the case please report back. Rich Quote Link to comment Share on other sites More sharing options...
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