Martin McIntosh Posted December 22, 2013 Share Posted December 22, 2013 Having a bash at this while waiting for the paint to dry on my Mustang. It is quirky enough to catch my attention. Obviously this is a tricky build but have come up against a couple of obstacles so far. The text states that the ailerons have a flat bottom but the ribs shown on the plan have pronounced undercamber with some reflex at the tip. The fairing ribs attached to the fus. sides do not show whether the sheeting goes over the top or is recessed below the top of the fus. This may become clearer when I get that far. Anyone else out there looking at or building this model yet? Quote Link to comment Share on other sites More sharing options...
Steve Terpstra Posted December 22, 2013 Share Posted December 22, 2013 I'm still waiting for my copy of RCM&E to come in the mail. I seen a picture of this model some time ago and knew it was a "Must Build" if the plans were ever produced. I'm also hoping that some one starts a build here so that those of us interested can follow along. Steve Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 22, 2013 Author Share Posted December 22, 2013 Tried to reply but it got lost. I think that the site is being updated as I cannot post pics here at the moment. Quote Link to comment Share on other sites More sharing options...
Mike Bell Posted December 22, 2013 Share Posted December 22, 2013 Hi Martin, I'll give Martin Bell a nudge (I'm hid Dad) and ask him to comment on the ribs. I suspect he means that the shape is flat enough to be laid direclty on a flat board without packing. Mike Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 22, 2013 Author Share Posted December 22, 2013 Thanks Mike. I shall try the picture download again soon. It said `please try later` after I uploaded the few I have, Martin Mc. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 22, 2013 Author Share Posted December 22, 2013 The site is back up but has reverted to its usual trick of not allowing me to insert text after pics. So here are the pics first: Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 22, 2013 Author Share Posted December 22, 2013 All went in backwards but never mind! I did not really intend to start a blog on this but rather hoped that someone was going to do one as I am still up to my ears with the Mustang. I decided to slot this in over Christmas while waiting for coats of paint to dry. Anyway, in reverse order, I spot glued the TE on then added the top spar which was pre bent by wetting and steaming with a heat gun. This prevents strain on the TE. I pre made the spar box and slotted this on as the ribs were added, using 1/4 sq. in the centre to maintain the slot width. I then cut and fitted the top rear sheeting. It would be silly to do this without first filing the slots for the carbon strip, would it not! It was then removed and the lower spar and sheeting added. The sheets were, of course, tapered before fitting. I hope that I can shape the aileron to that curved surface. This will be made next. Quote Link to comment Share on other sites More sharing options...
MartinBell Posted December 23, 2013 Share Posted December 23, 2013 Hi, I've put what pictures I have of my build in an album here: **LINK** I'm afraid they're not the greatest quality as I only had a naff camera phone at the time. As per my usual approach to designing and building there was a fair amount of 'make it up as I go along' involved. Even I had to scratch my head at some points during the build! As for your questions Martin: The ailerons do indeed have a bit of curvature to their underside but they're flat enough that you can get away with building them on a flat surface. Indeed, I wouldn't worry a great deal about cutting the subtle curvature into the ribs - a straight line would be absolutely fine. The sheeting for the fuselage fairing butts up against the side of the central fuz box with the highest point being flush with the top of the central box (if that makes any sense at all!). Maybe this pic shows it? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted December 23, 2013 Author Share Posted December 23, 2013 Hi Martin, thank you very much for joining in. A picture is worth a thousand words as they say and things are now very much clearer. Having already cut the ribs they are as per plan with under camber. The plan does not show the aileron LE (unlike the wing TE) but I have devised a pair. The way I have cut them means sheeting after shaping but should not present a problem. I am just in the process of cutting the aileron TE sheets to shape and shall use these as a jig to align the ribs on the LE. I shall be using a 35/48 1100kv motor on 4s and 6kg DMG MI servos @ 26gm each. It looks to me that you are either very good at cutting intricate parts or that a lot of this was laser cut. I shall be using GRP for the hinges etc. since I find this easier to work with than small bits of lite ply. Martin Mc Quote Link to comment Share on other sites More sharing options...
MartinBell Posted December 23, 2013 Share Posted December 23, 2013 Yes, the design was largely devised on CAD so I had a lot of the parts cut on a CNC router to speed things up. Patience is not something I have a whole lot of! Quote Link to comment Share on other sites More sharing options...
Colltheflyfisher Posted December 31, 2013 Share Posted December 31, 2013 Hi Martin, really like the loook of the Ellipse, I have a cnc router and was just drawing the plan onto autocad. You dont want to save me a load of time do you???? I can assure you Im not out to make money from your hard work, I just like accurate joints! Quote Link to comment Share on other sites More sharing options...
Steve Terpstra Posted January 1, 2014 Share Posted January 1, 2014 Mr Bell, I still don't have the plan sheet yet, can you tell me what the wing span and the projected weight is? Also, is this model hard, easy or somewhere in between to fly? It apears to be a mostly flat bottom wing so I'm guessing that it creates a good deal of lift? Thanks for your time. Steve Quote Link to comment Share on other sites More sharing options...
MartinBell Posted January 4, 2014 Share Posted January 4, 2014 Steve, The span is 49" and weight is in the region of 3 1/2 pounds. It flies pretty much like most other fun fly models but it can be a lot more twitchy if you use large amounts of control throw. However, if the controls are toned down then it is fairly simple to fly. Quote Link to comment Share on other sites More sharing options...
Steve Terpstra Posted January 4, 2014 Share Posted January 4, 2014 Martin, Thanks for the quick reply. Your Ellipse is on my must build list, still waiting for the plan sheet. Steve Quote Link to comment Share on other sites More sharing options...
JohnnyB Posted January 26, 2014 Share Posted January 26, 2014 Hi everyone, Just been reading through the January issue article/plan feature describing the build of the fun-fly model called the ELLIPSE. The bit that has me stumped though concerns the motor. In the article it says that its a home built "12 pole stator with 7 turns which operates at around the 750Kv mark." So, what I'd like to know is - what commercially available motor would actually suit this application at the higher end of the power range? John. Edited By David Ashby - RCME on 29/01/2014 08:52:44 Quote Link to comment Share on other sites More sharing options...
David Ashby - Moderator Posted January 29, 2014 Share Posted January 29, 2014 Post moved to existing thread Johnny, I know Martin stops by this one Quote Link to comment Share on other sites More sharing options...
glen johnson Posted January 29, 2014 Share Posted January 29, 2014 I would have thought the G32 motor from Hobbyking would be ideal £22 from UK warehouse here's the link John **LINK** Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 29, 2014 Author Share Posted January 29, 2014 I looked at that but does a 32 glow turn a 14x10 prop? No, so that is why I am going with the D3548/4 1100kv which is happy on a 10x6 at very respectable revs. I already use one. Quote Link to comment Share on other sites More sharing options...
glen johnson Posted January 29, 2014 Share Posted January 29, 2014 That's a fair point, but you don't have to swing that big a prop on 4s you're most likely to go for the 12" prop swinging a larger prop slower is more efficient The article does say the motor use is around 750kv Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 29, 2014 Author Share Posted January 29, 2014 I certainly see what you mean but I shall go with what I know works. It is difficult to figure out from the photos just what the original prop size may be. Considering the short span it may be 12" max. The motor I intend to try will swing larger than 10" and since full power would rarely be required, flight times should still be reasonable. Also I have a motor from the same stable as the G2 and it will not pull the skin from the proverbial. Now that the Mustang is complete I have returned to the Ellipse build. I have probably used as much debonder as glue on the ailerons so far just trying to get the ribs and tip alignment right. It is very difficult to shape the LE with the tip rib in place and impossible to build without it but I think that I am nearly there with this. The rest should be quite interesting. Quote Link to comment Share on other sites More sharing options...
Mike Bell Posted January 31, 2014 Share Posted January 31, 2014 The motor Martin uses is indeed home made so details are a bit sketchy. Prop size is 14x7 but we have never done any trials on other prop sizes, it works so haven't felt compelled to tinker. Other important consideration is that Martin uses 5s batteries. This is definitely overkill but he is of the never can have too much power school of thought, especially for competition. On 5s and 14x7 it can produce over 900 watts which is way more than what is needed to fly the plane. As with any Fun Fly type of plane, extended fast flight is not recommended as flutter is always a possibility and this isn't what they are built for. Full power is only ever used for climbing events and then only for 20 seconds at a time. I would suggest a good high performance set up would be an 800 watt motor on 4s batteries. The 4-max PPPO-3548-790 motor would be worth a look at. I have bought one to replace my Irvine 39 for next years Nats but haven't had an opportunity to try it in anger yet. Feels like it has plenty of thrust on the ground though. Mike (Martins Dad) Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted January 31, 2014 Author Share Posted January 31, 2014 Thanks for the info Mike. For first flights I shall stick with a small prop on 4s. Wings, ailerons and tail feathers now done. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 3, 2014 Author Share Posted February 3, 2014 Some pics of the progress so far. The tail feathers are now finished and covered in the obligatory clear film, in this case Solarfilm Polyester. These bits were thankfully straightforward to build. The carbon tube has been glued in with Liquid Weld. Just trying to put off that daunting fus and fairings. Quote Link to comment Share on other sites More sharing options...
glen johnson Posted February 4, 2014 Share Posted February 4, 2014 Looking good Martin what colour's are you going to be finishing the plane with? Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted February 4, 2014 Author Share Posted February 4, 2014 Same as the original except I was going to replace the blue with red but I seem to have run out of this so it may be transparent violet. Quote Link to comment Share on other sites More sharing options...
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