Delta Whiskey Posted September 29, 2010 Share Posted September 29, 2010 You may have seen my other thread about a Gentle Lady Glider, but as it turns out the one I have is called a 'Graduate' and is pictrured here: As you can see I've stuck a motor in it, and with a 2s 1100mah battery in the biggest gap you see above, and it feels far too tail heavy, so I did not attempt to maiden it yesterday when I had a chance, I've moved it up to the front section and it's still too tail heavy in my opinion, so I've been trying to find out the official C of G on google but cannot find out anything about a Graduate Glider, only about Graduates and gliders ! Anyone come across one of these? Also, I've not done any maths about the electric setup, so if I could gain some advice here too, I'd be much appreciated ! I have an 1800kv motor (yes I know it's too fast but it's the only one I can get to fit the nose section) and a 25amp ESC and was planning on using the 2s 1100mah 7.2v battery mentioned above on a 8 x 6 folding prop, but could also use a 11.1v 1300mah lipo which is heavier and may help with the above C of G problem - would do you think? Will it burn up and catch fire, on the bench after a minute run at full power all seemed fine, just a little warm to the touch with the 7.2v lipo, and it will only be on for ascent........and landing approaches? Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted September 29, 2010 Author Share Posted September 29, 2010 bump. Quote Link to comment Share on other sites More sharing options...
Lee Smalley Posted September 29, 2010 Share Posted September 29, 2010 use 30% of MAC mean/aero/chord looking at the wing i would just measure the chord and set the c of g at 30% of that and give it a chuck over long grass Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted September 30, 2010 Author Share Posted September 30, 2010 Thanks Lee. Well for the maiden today, it was a bit of a disaster! 1st attempt with a whole lotta lead stuck around the nose, and an extra battery squashed in to add more weight, it finally balance at 30% ish of the chord, and the setup showed on a test box that another flyer had, that it was pulling 30amps at full power, so they said the 25amp ESC would be ok ! The guy hand launching it for me said if you want to go over long grass and into the wind we launched if from the pits that only had a couple of cars in it, the glider struggled to climb then went into a right handed circle, trying to correct it on the rudder, it went even tighther into the circle and with the rudder on this 3 channel setup still on the throttle side, I decided to just close the power and hope for the best as it was not responding much. It went straight in between two cars clipped the wing tip on the rear of one car going in, and landed near the front of both cars! No damage to the cars or glider! Closer inspection revealed the rudder was reversed, so after moving it over to channel 1 (futaba setup), so that all the surface controls were on the right stick (mode 2) we tried again. This time it went straight but still struggled to climb and ended up going into a descending circle again, and the long grass came to the resuce, so good advice there from Lee! I have some spare 1300mah 3s batteries so will try them on my next outing, do you think this will improve the setup or am I just using too small a prop for this size glider (2.4m span) and if so what smallish motor can I get to fit on the SMALL nose section that would be suited for a larger prop? Thanks for any tips here ! Edited By Delta Whiskey on 30/09/2010 17:59:20Edited By Delta Whiskey on 30/09/2010 18:19:03 Quote Link to comment Share on other sites More sharing options...
Erfolg Posted September 30, 2010 Share Posted September 30, 2010 Ehmm, Is it the first of April? If not, seems a little hazardous to launch from the car park. It is a joke? Is the story meant to have us all reaching for the BMFA handbook, quoting pages and clauses which have been infringed? Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted September 30, 2010 Author Share Posted September 30, 2010 I hope not Erflog, perhaps I should have omited this bit , just trying to build my escapade of today attempts! It's a large grass pitts in the middle of a private enclosure that has long grass around it on one side so just with the wind gently blowing today from the direction it suited this launch that luckily the launcher recommended even with one of the two cars being his ! We prettry relaxed too on this sort of thing, but I think we can tighten it up a bit now ! No rule book bashing please ! Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted September 30, 2010 Author Share Posted September 30, 2010 Oh just found out it's a Model Air Graduate plans by a Ken Phillips. Quote Link to comment Share on other sites More sharing options...
Former Member Posted October 1, 2010 Share Posted October 1, 2010 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 1, 2010 Author Share Posted October 1, 2010 Seems to be exactly what was happening Eric , in skidding sideways I suspect because of the low forward speed. The more power of the 3s battery though should give it some more oomph I hope! Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 22, 2010 Author Share Posted October 22, 2010 Well, nice calm this evening saw me get two sucessful flights in using the 3 cell battery gave it enough umph on the same setup, however it was still a dog to fly ! Despite extra weights around the nose, and with the 2s battery still onboard, it was still too tail heavy. For a thermal soaring unpowered glider, I would have thought that by sticking in a motor, esc, and batteries it might have come out nose heavy but alas ! Next Calm day, I will try and cut out the nose area a bit more to move the 3s batt forward even more, but there's not a lot of room ! Anyway it flew ! Quote Link to comment Share on other sites More sharing options...
Stuart Mallett Posted October 23, 2010 Share Posted October 23, 2010 Hi delta whisky, I had a glider called the "Graduate" which came as a Kit which was a "100" inch soarer but had instructions on "electrification" in it. I believe there was a "Freshman" in the same seris, Aussie I think. It was meant for use with a brushed 600/700 direct drive motor, 10x6 folding prop and 6 - 9 c cell nicads with a servo operated power switch, safety provided by a 30-40amp car fuse!!!!!Maybe that explains why using brushless and lipos means it wont balance without the church roof on it. I carefully cut symetrical panels in the top,bottom and sides wherever I could to lighten the back end, this worked wonders.I think a friend of mine still has one that has never flown nor is likely to. I hope you get more success.I will stick to zero gravity inducing foamy models if you dont mind. Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted October 24, 2010 Author Share Posted October 24, 2010 Thanks Stuart, I may have to start thinking about chopping bits out of the back end, though if it is designed to be a soarer alone, then even more weight up front would be needed ! It's far too heavy for a soarer but the power setup I now have seems to handle it well, even if I have got too small a prop, which the faster motor makes up for! Just got to balance the damn thing, and it should be good for these still cold bright winter days ! Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted October 24, 2010 Share Posted October 24, 2010 Hi D/W You say it is to heavy for a soarer, can you give any details such as wing/loading and AUW emty. Thanks FB3 Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted November 15, 2010 Author Share Posted November 15, 2010 No idea fly boy3 sorry - but just to update you I had another go this time I managed to move the 3s 1300mah battery a little more forward and it flew fine this morning in the patchy fog but still air and it was very graceful and a joy to fly ! On power it still climbs to much vertically, but with holding the nose down a bit as power is added you can climb more controllablly. Once up closed the throttle and it did just float around, and with all the weight up front any slight dive it picked up speed quickly to give the control surfaces more authority. My brother the builder was there two and was chuffed to see his first build fly ! Back home now, the fog has cleared and the sun is out !!! Quote Link to comment Share on other sites More sharing options...
Lee Smalley Posted November 15, 2010 Share Posted November 15, 2010 put some down thrust in it mate ! Quote Link to comment Share on other sites More sharing options...
Delta Whiskey Posted November 15, 2010 Author Share Posted November 15, 2010 good idea, but that then makes flying it not a challenge ! Will do ! Quote Link to comment Share on other sites More sharing options...
Windsor Posted May 3 Share Posted May 3 Hello, apologies for resurrecting an old post but I’m looking for the plans for this glider. I have an unbuilt kit called ‘freshman’ by Modelair the original photo on this thread looks very similar to the box photo I have so I’m fairly sure it’s the same plane. If the plans are tucked away somewhere I’d appreciate the opportunity to scan or copy them (if allowed) Many thanks in advance Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted May 3 Share Posted May 3 Hi Windsor - welcome to the forum. I suspect that although similar, the Freshman will be a different design by the same company (Modelair?) as the Graduate - in fact, there is mention of the Freshman in a post above… Quote Link to comment Share on other sites More sharing options...
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