TonyS Posted February 27, 2011 Share Posted February 27, 2011 Hi Chaps, I've hunted around for a blog on this beastie and can't find anything that does it for me. On that basis I'm going it alone so to speak.... I ordered the 52" as the 80" is a short kit and frankly, I need all the help I can get. The pack arrived from the US and I had to cough up the obligatory taxes before HMRC would let me get my hands on it. The kit is remarkably small i.e. a rolled plan - 1:1 scale, a pack of laser cut sheets of ply and varying thicknesses of balsa, a couple of carbon spars and a tiny pack with two small tubes in it. The only other item is a bundle of stapled A4 sheets giving the instructions with pics. All good so far. The cut parts are, I must say, some of the very best I've ever had the pleasure to work with. The accuracy of the fit of every piece is amazing. So much so that the wings were built within a couple of short hours and I got so engrossed with the speed of it all I didn't take any photos. Doh! I shall post a few pics in a minute when I've taken some... Quote Link to comment Share on other sites More sharing options...
TonyS Posted February 27, 2011 Author Share Posted February 27, 2011 First the parts sheets - brilliant cut. Then the wings... The wing tips have dihedral.. Quote Link to comment Share on other sites More sharing options...
TonyS Posted February 27, 2011 Author Share Posted February 27, 2011 The missing bit of the build blog is straightforward really. I like to lay the plans out with some thick polythene sheet over to protect from glue drips. In this case the build calls for thin cyano which wicks beautifully into the close fitting joins. To begin with you lay the ribs onto the plan. As it's a full scale plan it can be used to place accurately. The ribs are numbered. Most of the remaining pieces are not. Occasionally to prevent confusion parts are labelled B for bottom and T for top. Sliding all the ribs onto the main and second carbon spars is a pain doe to the very close tolerance of the cut but take your time and they do eventually go on. The carbon spars have to be cut to size. I would recommend NOT cutting to the measurements in the instructions but to mark the lengths from the plan. The leading edge ply parts all fit very snugly and the outside ply parts on each wing have a tab that inserts into the tube. In this way, the spar is held in place. I measured mine according to the instructions , 41.4" for the front spar and 45.4" for the rear. Now there's confusion. Come on you yanks. You either want to stay imperial or go metric but 41 point 4 inches !!! Anyway, I digress.... Quote Link to comment Share on other sites More sharing options...
TonyS Posted February 27, 2011 Author Share Posted February 27, 2011 Once all the Leading edges are on you can fit the trailing edge ply parts. As everything interlocks it's like building with meccano. Once these are in place it's possible to glue the doublers at the centre of the wing and behind the motor mounts. Now for some advice... Make sure you buy the motors etc before building. The motor mounts need fitting around now and the kit kindly provides either pre-drilled mounts or blanks that you can drill yourself. As I haven't got my motors I don't know if the pre-drilled ones will work with my motors so I had to stop building the wings and go onto the head and body (erm... nose and fuselage...) You are told that to complete the kit you will require two motors, two ESC's, a battery, a receiver, two props and 4 micro servos. There are recommendations given. What they rather frustratingly don't tell you is that will also need some wing retaining bolts and nuts as these aren't supplied. I plumped to do all my shopping at BRC and bought: 2x A2208-14T 1450Kv (120W) motors 2x BRC Brushless 20 Amp ESC's (probably a bit of overkill but that's how I like my ESC's 6x5.5 APC props 2x BRC -9 9g micro servos rated at 1.5Kg 2x BRC 9HT micro servos rated at 2.2Kg A Speccy receiver Had I known I'd have thrown in a couple of wing bolts and nuts but there you go.... Quote Link to comment Share on other sites More sharing options...
TonyS Posted February 27, 2011 Author Share Posted February 27, 2011 The head and neck come next and this again, is a breeze as all the bits slot together. I thought I'd found a part that didn't fit - sometimes the building instructions are a little too brief and you have to play around a bit at first. With this kit I would say ALWAYS dry fit all the bits first. I would also add that if you think a part won't fit without modding then you've probably not worked out how it goes together. The head looks lovely when it's done.... Oh I nearly forgot - you'll need around 2 oz of lead to stick in the head too! Quote Link to comment Share on other sites More sharing options...
Peter Gallivan Posted March 7, 2011 Share Posted March 7, 2011 Hi Tony, just found this blog!!! I am just starting to cover my pterodactyl great build and great fun!!! spent ages rubbing down the sheeting but worth it a it looks so good. Keep up the good work hoping to have mine ready to chase a few parakeets!! I have a couple of Scorpion S-2212 (1920kv) and 30amp Ripmax Dragon Esc's bit ott I know!!! Savox servos in the wings and a couple of snall chep LSX 180 9grm servos for the tail. Tested it on a 3cell Lipo with 6x5.5 props and sounds wicked. need to finish the covering (have done the ailerons!!! plucking up courage to do the wings using transparent Oracover red for the wings and yellow gold for the rest. keep up the good work I shall be watching with interest!! Peter Quote Link to comment Share on other sites More sharing options...
Andy Green Posted March 15, 2011 Share Posted March 15, 2011 Hi Tony Have you seen my build on the 80" version. Or more details Here. AndyEdited By Andy Green on 15/03/2011 08:09:34 Quote Link to comment Share on other sites More sharing options...
TonyS Posted March 17, 2011 Author Share Posted March 17, 2011 Looking forward to seeing pics and video? Peter. Sounds like a monster...! Andy, thanks for the links - I'll be having a look through them tonight. Quick question for you though. I'm at the point of wiring up the motors and these are soldered to the ESC motor wires (as the wires are sheeted into the LE of the wing I figured ..why not? This is however my first twin motor and I was wondering. Should I reverse the rotation of one of the props to balance the whole thing out? All ideas / thoughts / instruction gratefully received. T Quote Link to comment Share on other sites More sharing options...
Andy Green Posted March 17, 2011 Share Posted March 17, 2011 Tony I don't think there's any need to change rotation of one of the motors, I've not heard of this before. The real problem with twins is loosing one of the motors, and the model Yawing under power, but this is less of a problem with electrics. One thing I want to try is to mix rudder with throttle ie on rudder slow down one motor & speed up the other to aid with Yaw. Mine is fast, flys like a pylon racer. But great fun. Remember it's the ESC to motor wires that are extended, and check rotation before you seal the wirs in. Andy Edited By Andy Green on 17/03/2011 08:59:48 Quote Link to comment Share on other sites More sharing options...
TonyS Posted March 17, 2011 Author Share Posted March 17, 2011 OK, back to it but for a short time only so..... All the parts arrived i.e. motors, ESC's, servos etc etc. Then I ad to order a stock of wire (to extend the ESC to motor sections, shrink wrap tubing, Y lead harnesses (to join the two throttle leads from the two ESC's) and for the ailerons. (There is a lot of thinking and shopping to do to complete this kit!!) Finally wired up the motors and, despite thinking about this beforehand and, despite the reminder from Andy I managed to solder the wires and shrink tube them before realising I hadn't checked the direction of rotation!! Guess what, .....they both were rotating clockwise so that was two wires to swap on both sides........ Oh, well...... So, firstly I glued on the lower LE strips, clipped while the glue gripped.... Then onto the bench to see progress but mainly to dry-fit the various pieces of wing sheeting.... Then wiring up the motors.... Note that I've used some scrap depron to hold the ESC's in place. The aileron servo is not yet secured. Looking quite good. I am nervous about having soldered all the wiring connections and sheeting in the motors and wiring. There's also very little room so I won't be able to easily use removable servo mounts. Still, it should all keep the weight down. Quote Link to comment Share on other sites More sharing options...
TonyS Posted March 19, 2011 Author Share Posted March 19, 2011 I'm thinking of the covering and fancy a skin-like finish (think of a bat wing).by this I mean instead of the cut outs being totally transparent I'm thinking of tissue and dope with a brown finish, darker on the solid parts of the wing and very pale at the open areas so they look semi-opaque.The last time I used tissue and dope was 1980! Anyone any ideas / thoughts?T Quote Link to comment Share on other sites More sharing options...
TonyS Posted March 28, 2011 Author Share Posted March 28, 2011 A bit of progress has been made and I'll report further shortly. Just thought that it might be worth adding a note of caution to anyone planning a similar build. I bought some 9g servos to operate the V Tail but as you'll see from the picture, these do not fit into the fuse where suggested (and given the VERY tight space there are no real alternatives). I am now buying some Ripmax SD 100's which are a low profile servo rated at 1.1Kg rather than the ones I have which are rated at 1.5Kg. I'm hoping that these will be up to the job. The alternative is to start carving into the fuse sides which would really weaken the whole plane. Quote Link to comment Share on other sites More sharing options...
TonyS Posted April 8, 2011 Author Share Posted April 8, 2011 Right, back on for an update.... The Ripmax sd100 servos arrived and these fit beautifully into the fuselage. I do hope that they're powerful enough for the job. Can't see why not as this shouldn't be ridiculously fast and, given the short fuselage the pitch will be highly sensitive to elevator movements so not much should be required. The pushrods that I'm using for the control surfaces on the elevons are 1.5mm carbon rods with plastic clevises... The clevis has rather a large spindle and this meant drilling out the control horn at the servo end. This left a very thin connector and I'm guessing that it wouldn't take too much punishment to break this so I'm going to have to be VERY careful...(See the pic two up for the extent of the problem).. Now the servos are in I can finish off the filling and sanding and worry about the covering. Quote Link to comment Share on other sites More sharing options...
TonyS Posted April 8, 2011 Author Share Posted April 8, 2011 The fuselage is not as much a squeeze as some of the models I've had to play with and I'm only using a 1700 mAh battery which gives me a bit of extra room.. Filling the wing leading edges is being done using balsa colored Model Lite. Because of the shape of the wings there are some ridges in the LE that need treatment... I'm still agonizing over the covering material. I'd love it to look like skin but would also prefer to use an iron on. I think that I'm going to have to plump for tissue and dope but we'll see.. Quote Link to comment Share on other sites More sharing options...
TonyS Posted April 22, 2011 Author Share Posted April 22, 2011 Finally stopped agonizing over the covering and went for tissue and dope. The nice chaps at Ben Buckle supplied the tissue and I bought some Deluxe materials Tissue paste. The web, which often contains total rubbish came up trumps with lots of advice on tissue covering which I read carefully. Some of it I followed and some I made up. Before I begin I'd like to say how easy it has been (so far) to get an excellent tight covering. The method I used was pretty straighforward. First, cut a piece of tissue roughly the right size to cover a section of the bit to be covered. Next, paste around the perimeter. I made sure that where the pieces overlapped it was solid sheet... Then stick the tissue around the edges... Trim the excess to give a reasonable bit to wrap around the edges (about an inch).. Then, where the edge is curved cut the edge at regular intervals.. Turning the piece over I then put a bead of paste on the reverse under the excess flap.. Then gently rubbed the excess round the edge squeezing the paste out. After a few very quick panels... With the paste dry i used my fingers to smear a little water onto the tissue being careful not to over wet. I hadn't pre-treated the balsa underneath so I needed to ensure it didn't soak the balsa and risk warping the wing. When the water dried the tissue went taught. When I'm done I'll dope it with shrinking dope. I'll need to weight the wing during drying to ensure it dries without warping due to the stretch and so it retains the washout. Quote Link to comment Share on other sites More sharing options...
TonyS Posted April 22, 2011 Author Share Posted April 22, 2011 Sadly I ran out of tissue paste so I'm hoping that my club shop has some tomorrow - fingers crossed..... Quote Link to comment Share on other sites More sharing options...
Andy Green Posted April 23, 2011 Share Posted April 23, 2011 I use wallpaper paste, another thing to note, using water with dope you might see some white patches, just a quick brush with cellulose thinners will get rid of them. A PS Tissue is easier if put on wet, dunk it in a bowl and ring it out.Edited By Andy Green on 23/04/2011 22:04:45 Quote Link to comment Share on other sites More sharing options...
TonyS Posted April 23, 2011 Author Share Posted April 23, 2011 Top tip Andy.I shall go in search of some wallpaper paste tomorrow.T Quote Link to comment Share on other sites More sharing options...
Matt Chamberlain Posted May 6, 2011 Share Posted May 6, 2011 Hi Tony and all other watchers of this thread. I'm watching on with great interest on the progress of Terry! I've just started my 52" Marston Pterodactyl and will post updates on this thread too. Not wanting to swamp Tony's progress on here, I'm documenting my build on my blog which can be seen as follows: http://mjc70.blogspot.com/ Obviously feel free to view this and comment with any tips which you might have. Now I'm underway with the build, I intend to update this regularly leading towards hopefully videoing the maiden flight. Tony and I have also privately discussed meeting up (as we live relatively close to each other) and getting the UK twitchers interested about a breeding pair of Pterodactyls flying over the Midlands area! Quote Link to comment Share on other sites More sharing options...
TonyS Posted May 6, 2011 Author Share Posted May 6, 2011 All sounds great to me Matt. I'll post some pics later today of Terry - he's looking very good now he's fully clothed! Unfortunately I now have to paint him (not my best skill) so I'm hoping for less wind this weekend - I paint outdoors! Hi Matt, In terms of the build I did make one change. I've gone down the route of hinges rather than using the wing covering - clearly you can't rely on the covering when you've used tissue and dope! The other problem I have is the weight in the nose. The plan says to put 2oz of lead up front and I hate using lead for weighting. Instead I'm going to cover the head in ultra light glasscloth and Poly-C as it looks so fragile one crash would destroy it completely. That's some of the weight replaced but this time with a benefit. The second thing that I intend to do is going to be more radical. I'm going to cut it's head off! What I'm going to do is saw it across the neck and re-attach using rare-earth magnets. I figure that if it does then crash then the glassing will stop the head shattering and the magnets will just let the head detach. Well, it sounds reasonable to me ....Pics later.... Quote Link to comment Share on other sites More sharing options...
TonyS Posted May 6, 2011 Author Share Posted May 6, 2011 As promised, The only thing missing are the control surfaces .... oh, and a bit of paint....... Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 6, 2011 Share Posted May 6, 2011 Looks absolutely superb Tony. Did you manage to buy the kit in the UK? Quote Link to comment Share on other sites More sharing options...
TonyS Posted May 6, 2011 Author Share Posted May 6, 2011 Hi Chris, No, I had to buy from the States but it was quick and no hassle. It is a superb kit - the cutting is so precise it really is a joy to put together. T Quote Link to comment Share on other sites More sharing options...
Matt Chamberlain Posted May 6, 2011 Share Posted May 6, 2011 Chris, you can find the kit as follows: http://www.pteroworks.com/ptero_52.htm CheersMatthttp://www.mjc70.blogspot.com/ Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 6, 2011 Share Posted May 6, 2011 Thanks Matt I'd already found that but I haven't had much luck with ordering from the States what with high postage charges and being stung for import duty.. Also found them available in Germany HERE. It's a shame I have other projects on at the moment, I really like the look of this. There was one at the RCM&E 50th bash last year, looked very nice indeed. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.