Martin McIntosh Posted October 22, 2014 Share Posted October 22, 2014 Correct. If you look at one of my pics above you will see that the red wire from three of the ESC`s has been disconnected on the 4 way Y. A UBEC could be fitted to the remaining ESC but since the servos on a model of this type are unlikely to draw more than 2A this should be unnecessary. Quote Link to comment Share on other sites More sharing options...
Alan Jarvis Posted October 23, 2014 Share Posted October 23, 2014 I bought a Quad ESC and the problem being I could not fit it in the limited space in the thrust tube bay so ended up buying four ESC's. I will have to buy a quad frame now. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted October 29, 2014 Share Posted October 29, 2014 Doing the intakes. Now where do I cut this? Shall have to think of something. Quote Link to comment Share on other sites More sharing options...
Colin Bernard Posted October 29, 2014 Share Posted October 29, 2014 Martin, I haven't quite got to that stage, but what I was planning to do was to insert the whole tube, while wet, into one of the intakes and then use the leading edge as a guide to marking where to cut, with the marked line off the plan warning me if I am wildly out. By the way, as to mounting the quad ESC I have found that it just fits on edge, with the wires front and back, tight against W1 and as far forward as possible. Now trying to think of the best place for the Rx. The other side of W1 is the obvious place, but dont like it being so close to the ESC. Alternatively against W3 or maybe even in the nose wheel void since I am not using an undercarriage. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted October 29, 2014 Share Posted October 29, 2014 Posted by Martin McIntosh on 19/10/2014 11:45:49: Anyone worked out a way to form the tubes from laminating film? I have cut a piece to the correct shape with 10mm overlap but it seems to have a mind of its own. May have to try making a balsa one then wrapping the film over this. Posted by Steve Balaam on 19/10/2014 13:08:26: I have used the program cone layout before to calculate the template required, I believe it will also add construction tabs to aide assembly, please look at **LINK** Another idea, when you have the template cut out would be to cut two ply/balsa discs separated the correct distant by a dowel and use this as a forming tool to construct your efflux tube around Steve B Started my thrust tubes today and same as you martin, its a head scratcher all right but thanks to Steve for the links and eventually I used this freeware/shareware program (whatever you have 21 days to use it) as shown within Steves link, and its really good Simply punch in the diameters of the fan unit and tail end plus length of the tube into the program and it will generate a pattern for you to print off, this necessitated 3 sheets of A4 paper Scalpel off the pattern and join (it shows you the join sequence) on the reverse with masking tape. Im using A3 laminating pouches. split them open (you only need one side obviously) and I found on a test piece my covering iron seals it nicely. The black felt line is simply an extra 3/4 inch overlap for the iron to seal down. Some pics below of a mock up test with it held together with masking tape. Once set up I will remove the rear former and fan unit and use the above mentioned idea of a broom shank inserted for something to press onto whist sealing it with my iron. Ive saved the pattern as a PDF if anyone wants it PM me for return via email Craig Edited By Craig Carr on 29/10/2014 17:09:41 Quote Link to comment Share on other sites More sharing options...
Glenn Philbrick Posted October 29, 2014 Share Posted October 29, 2014 Hello Colin. I am also thinking of using a Quad ESC, any chance of a photo of how you mounted it, Have you made any allowance to provide cooling air to it? Are you using the HK Esc ? Thanks, Glenn Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted October 29, 2014 Share Posted October 29, 2014 Those tubes are very neat, much better than mine which are now fitted. Be very careful with the rest of the build as these are easily crushed. I too tried to fit the intakes one at a time and cut them afterwards. The central supports may act as a guide but I found them to be an unnecessary nuisance so removed them. Even so the tubes did not want to fit very well. I may regret this but have decided to dispense with them altogether since they seem to serve no purpose other than to restrict the intake area. I have measured this against the efflux area without the tubes and this works out at an outlet of 85% of the intake which should be ideal for quick accelleration from what I have managed to glean. I may be just talking through my hat of course since this is as new to me as anyone but we shall have to see! Quote Link to comment Share on other sites More sharing options...
Alan Jarvis Posted October 29, 2014 Share Posted October 29, 2014 This is the ESC I bought and there was no way it would fit in the bay. **LINK** I inserted the intake in one side drew round it and then cut with an hacksaw - very easy. I don't plan putting the centre supports in as they serve no useful purpose on a model this size. I am using a Spekrum AR636 AS3X stabilisation receiver so needs to be near CofG so planning to put it in the wing retract bay with a cover as not using retracts. I am having a problem fitting the plastic cover over the motor/ESC bay. It is not wide enough to fasten as indicated on the plans. so need to make up some additional framework. Quote Link to comment Share on other sites More sharing options...
Colin Bernard Posted October 30, 2014 Share Posted October 30, 2014 Hi Glenn Like Alan I am using the HK quad ESC, except mine is the 25A version. Here is a pic of it in situ ... Just enough room for the motor leads to go over/under the tubes. As for cooling I will test first before I do anything, but if I find it is getting warm then I plan to drill a 5mm hole top and bottom either side of W1 Quote Link to comment Share on other sites More sharing options...
Colin Bernard Posted October 30, 2014 Share Posted October 30, 2014 Duplicate post for some reason Edited By Colin Bernard on 30/10/2014 12:32:45 Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted October 30, 2014 Share Posted October 30, 2014 Don`t want to fill this up with my pics but I thought that you may be interested in the progress so far. The turtle deck proved to be much easier than anticipated. Quote Link to comment Share on other sites More sharing options...
Alan Jarvis Posted November 2, 2014 Share Posted November 2, 2014 Fired up the four fans and a little disappointed with the amount of thrust although probably enough to fly. I will do some static thrust measurements in the next day or two. Technically 4 x 50mm =200mm EDF however some of my 70mm planes seem to have more thrust and certainly my 90mm planes are way more powerful. This is all subjective at the moment whilst holding them/it in my hand. Quote Link to comment Share on other sites More sharing options...
PeterF Posted November 2, 2014 Share Posted November 2, 2014 Techincally 4 x 50mm fans = 100mm fan because it is the area (diameter sqaured) that is important not the diameter. Additionally, 50mm fans tend to have a relatively larger motor sat in the middle than a 100mm fan, hence more area is obscured and the free flow area of the fan is even less on a proportionate basis. Quote Link to comment Share on other sites More sharing options...
Martin Rowe 1 Posted November 2, 2014 Share Posted November 2, 2014 Hi i have some beginner Q's if thats ok? This is my first ever building and am finding getting the bits together a challenge What hinges are best and where to buy? what servo covers would you recommend? Where can I find good quality servo push rods and track rod ends? where can I get some mat NATO green covering film? What makes are good? I skinned one wing today, I a bit surprised how simular the top and bottom wing profile is. It's good fun though, I can see why people get hooked on building. I,am finding very relaxing. Listening to a E book as I go. thanks in advance Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted November 3, 2014 Share Posted November 3, 2014 I have now built one wing half ready for the top skin. To get me more into my comfort zone I have changed the construction sequence somewhat so that the skin can be pre made, sanded, and fitted as one piece. You will see from the pics that the elevon LE and TE has been fitted, plus a few mods to the tips of these. As per my original idea I shall use four wing servos. The wing TE has 1/64th" ply fitted top and bottom to define and strengthen this. The tip washout has been preserved by adding packing pieces. I had a small problem with W6 since this seems not to be tall enough but should not be noticeable at the end of the day. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted November 3, 2014 Share Posted November 3, 2014 Martin R., Firstly may I congratulate you for attempting such a difficult subject as a maiden build. I have many dozens under my belt but have found the fus. to be rather more than tricky. Regarding your queries there are many differing answers depending on personal preference. Hinges. I now only use the thin fluffy ones from SLEC which must be fitted with thin Zap or similar. Many cheaper versions of cyano are just not thin enough. They can be cut in half for small surfaces. Covering. I use silver Solarfilm if the surface is to be painted (Spectra). Polyester such as Supershrink or Profilm is difficult to paint since it does not adhere well to the finish. Much of this model will be a problem with iron on stuff so I intend to tissue and dope these areas. Servo covers. Don`t bother. Linkages. These can be a real problem for a novice and there are many ways of doing them. For this I shall use SLEC 2mm threaded rods cut and re-threaded at one end to accept SLEC mini ball links. You could alternatively put a Z bend at one end but considering the small size of most mini sevo arms this could be dodgy. Whatever you decide on do not use any with a grub screw. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted November 3, 2014 Share Posted November 3, 2014 Main undercarriage warning. Use the photos, not the plan to fit UC3 otherwise the leg will not retract! Quote Link to comment Share on other sites More sharing options...
Martin Rowe 1 Posted November 3, 2014 Share Posted November 3, 2014 Martin M thanks for the answers. I have seen those hinges. I can't help the feeling they should be more complex! What at undercarriage is that? Could you send me a link to it? If I read what your are suggesting I should invested in a m2 die? I like the idea of making them up as you need to. I am not sure how I feel about flying it when finished. I think,I,will find the best pilot possible for the maiden. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted November 3, 2014 Share Posted November 3, 2014 Hi Martin R., Those hinges are all that is required these days up to at least a 2m model. They will not pull out and only need a knife cut to fit. As I said above, you should get the retract units from Tony if only because they have to be modified. I always run a 1.6mm drill and a 2mm tap through the horns and arms to give extra security and ease of fitting. Snip off the end and add a dab of glue. I would certainly invest in a 2mm tap and die set (very cheap). Another way which I use a lot is to solder some threaded rod in a tube to one end but you need fairly good soldering knowledge to do this properly. Quote Link to comment Share on other sites More sharing options...
Martin Rowe 1 Posted November 4, 2014 Share Posted November 4, 2014 Thanks, pics helped a lot. Quote Link to comment Share on other sites More sharing options...
Alan Jarvis Posted November 5, 2014 Share Posted November 5, 2014 Carried out some static thrust tests today which came in at 60 ozs. Given that the Vulcan is projected to weigh 3.5 lbs = 56 ozs that gives just over 1:1. So things are looking good. Quote Link to comment Share on other sites More sharing options...
Martin Rowe 1 Posted November 5, 2014 Share Posted November 5, 2014 Was the fans stock? Or did you shim them? Quote Link to comment Share on other sites More sharing options...
Alan Jarvis Posted November 5, 2014 Share Posted November 5, 2014 Fans were stock and using 3s 2200 35c. I have connected the two inner fans to one battery and the two outer to the other. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted November 5, 2014 Share Posted November 5, 2014 Alan, Do your fans have the later, larger, outer diameter? Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted November 6, 2014 Share Posted November 6, 2014 Posted by Martin Rowe 1 on 02/11/2014 20:42:43: Where can I find good quality servo push rods and track rod ends? For short lengths you could always use threaded rods, Model Fixings are a good source of this (and lots of other stuff, I really like their cap head servo screws). Another option is carbon fibre rods with the threaded adjusters glued on, a selection here 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.