Tom Foreman Posted October 27, 2010 Share Posted October 27, 2010 I will probably go down the glider route, pull - pull rudder and carbon tube pushrod for elevator. What size servos are you going for? I was looking at some cheap Hobby King high torque servos with metal gears at the £10 ish mark, too cheap? Tom Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 Hi Tom, I am trying to keep mine very simple. I am still thinking but closed loop for the rudder is a good simple method. Cheers Danny "One of your elite, trying to land without wheels" Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 Hit a snag.... The fus sides are so stiff because of the 25mm triangular section they will not bend in towards the tail. The amount of force required is very high and is causing some nasty cracking sounds. It is not shown on the drawings but I am going to slot the triangle stock, in the same way it was slotted to curve to the shape of the underside. I must confess I like to build a model from sheets of wood, not force sheets of wood into a model Cheers Danny "Boomsey daisy..... its enough to make you want to weep" Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 Okay found the problem F5 appears to be incorrect on the drawing. It is 10mm too narrow. The part has been accurately cut as per the drawing and therefore is also wrong. The height is good but as you can see it is too narrow. Herri, if you are looking in can you take a look at F5 on your drawings and measure the width? Cheers Danny I know its been said but its a cracker so we will have it a again.. "You can teach monkeys to fly better than that"Edited By Danny Fenton on 27/10/2010 12:29:21 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 The new F5 has been made and dry fitted. It looks just about right, and the fus sides are no longer straining so much. I think slotting the triangle stock was still worth doing however. I have made an error, well somebody has to lead the way and this is the price. Momentary lack of concentration on my part. I have cut the triangle stock away to allow the tails to pull together. Well I forgot to allow for the tailpost Anyway from the attached pic you will see the area in the red triangle labelled C is the bit I will have to "put back" no big problem. While this picture is to highlight this, it also shows another little method for aligning the rear of the fus if you haven't got a fus jig. (Which would be very handy on this build.) If you look at the tail I have pulled the two fus sides together using two identical thickness blocks, in this case two 1/2" blocks. (The thickness doesn't have to be the final thickness.) You will see that A = B in the pic. The clever bit is if you eyebal down the line that is formed where the two blocks touch (black line perpendicular to the orange line), it should intersect on the middle of the fin post on the drawing below. At least then you know the tail is central on the fus. Tally Ho!!! "How many hours on Spits Simon? On Spits Sir... 10 1/2, well lets make it 11, before Jerry has you for breakfast..." Edited By Danny Fenton on 27/10/2010 16:01:11Edited By Danny Fenton on 27/10/2010 16:06:37 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 F5 is still not right. Just widening the whole bulkhead by the missing 10mm has made the bottom section correct but the upper part is too wide now. I will redraw the bulkhead as an interim between F4 and F6 but without the original fus sections to go by its a bit trial and error. A shout has gone out to Tony, but no news yet Cheers Danny "Spring chicken to shite hawk in one easy lesson" Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 27, 2010 Author Share Posted October 27, 2010 Okay F5 mkIII and this looks pretty good both on the lower section and on the upper curved part. In the photo you will see that there is now a straight line between the top edge of F4 and F6, this line now passes through the top edge of the new F5. Tally Ho! "TAK TAK TAK TAK TAK" Quote Link to comment Share on other sites More sharing options...
Herri Posted October 27, 2010 Share Posted October 27, 2010 Just got in. (had to earn some hobby money 1. I hadnt given much thought to a steerable tail wheel but I shall have a look how much room I have when I get around to the rudder connections. 2. My F5 is the same as yours at 80mm at the centre. My plan also meassures 90mm looking from the top. I am pleased you have noticed before I started glueing ' Cheers Herri Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 Hi Herri thanks for checking. I can still rip mine out if its wrong. Hopefully will hear something in the morning. Brushed the outside of the fus liberally with water and after it had time to soak in started easing the fus top sides together. Left it fo 10 minutes then more water and eased it a bit more. After 30 mins or so the rea fus is now together. I clamped it all with tape. The front however is a different story. Its still miles away and I can hear loads of cracking and creaking. I have slapped more water on and will leave it clamped as far as I dare overnight. Will see how it looks in the morning. But I am asking 1/4" sheets (Tony's prototype only used 3/16 on the upper surfaces) to bend with 1" triangular stock at the edges. I feel another session with the razor saw in the morning. Time for sleep............ Quote Link to comment Share on other sites More sharing options...
Stephen Grigg Posted October 28, 2010 Share Posted October 28, 2010 Bit challenging Danny Quote Link to comment Share on other sites More sharing options...
Herri Posted October 28, 2010 Share Posted October 28, 2010 I have just dry fitted mine as I was somewhat concerned. Funny thing is, it looks ok. F5 with just a tad of finger pressure. admittedly I havnt yet glued the triangular stock on that side. I still have a bit to do before I get to glueing and tomorrow I'm out and about again so no building Cheers Herri Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 The continuing saga of the front end. I found the reason for the front sides not meeting at that was because the triangle section was too low. I would guess that on Ton'ys original drawings the triangle stock went too the edge of the fus sides. Because the cut fus sides are only as tall as the profile sides the triangle stock (even though overhanging the edge) are still too far inboard of the fus side. ( I think it might have been better to fit the triangle stock AFTER the fus is joined and curved, not sure if that is possible? Anyway I cut slots in the triangle slot to allow the fus sides to clear. Anyway cutting yet more slots this time perpendiculr to the previous slots allowed the 1/4" sheet to curve as required. However as you will see the triangle stock still could not take the forces involved. I think much of this has come about because the cut fus sides are all 1/4" thick. On Tony's drawings, and his photo build shots the upper sections (the bits that bend) are 3/16. I could of course be completely wrong and I am misinterpreting the drawing. Ho Hum Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted October 28, 2010 Share Posted October 28, 2010 Danny could any of the profiling be done before bending the 1/4" Even just taking the thickness down a bit? Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 Hi Chris. I haven't shown it or mentioned it but one side I attacked with a razor plane and made somewhat thinner. It didn't help much. Perhaps I have misunderstood the build sequence perhaps I should have sanded a 1/16 of all the provided fus sides before I started? Quote Link to comment Share on other sites More sharing options...
Hugh Coleman Posted October 28, 2010 Share Posted October 28, 2010 When I built the fuse for Tony's 62" Spit, I fitted all the Triangle strip AFTER the sides had been attached to the bulk heads and the bending and warping had been done. I did find that the Strips along the top of the nose section protuded a little. But then, I also cut all my bits from scratch (Using the plans as a guide more than gospel) and fitted each bit as required. Cheers, Hugh Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 Hi Hugh Thanks for joining in mate I think you were sensible to do the build the way around that you did. The way I have done it I have had very little control over the amount of bend each side has taken because of the industrial sized tools to bend the structure. And i think one side may have more than the other. When one side triangle stock broke it then bent more easily. I may cut the triangle stock off and re do the curve, not sure yet........ Cheers Danny Quote Link to comment Share on other sites More sharing options...
Hugh Coleman Posted October 28, 2010 Share Posted October 28, 2010 Well, basically I followed the method that Tony decribed in his build article. In any case, we have to remember that the triangle strip is only there to give material to carve away later. It really has no structural benifit... Just adds a lot of weight (especially at the back end). Cheers, Hugh Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 On Tony's website the build notes for this bigger Spit show the triangle bits fitted first, thats exactly why I did it that way Maybe I should have looked at the smaller Spit build threads I am hoping most of the triangle stock will be shaved off Cheers Danny Quote Link to comment Share on other sites More sharing options...
Tony Nijhuis Posted October 28, 2010 Share Posted October 28, 2010 Hi Guys, David Ashby did alert me that F5 may be a bit narrow. I have just checked my plan and Danny you are right, the width of F5 is smaller than shown in plan section. Not sure how this has happend as I thought I had pick up all the issues. I must be lossing it Herri, i think yours looks ok until you start to pull the front and rear together...I think it may show up then I will up-date my plans ASAP and get F5 altered in the CNC pack, then commit 'harry carry' Even though my memory is short nowerdays, did remeber the bending / rolling of the top side did require plent of wetting, clamping, wetting, clamping, etc and thinking i hope you guys are up for this!...it was the worst part of the build for me. Once the top sheeting is on, the structure becomes very rigid and its down hill from then on..... Keep up the good work guys..... Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 28, 2010 Author Share Posted October 28, 2010 Tony if you think your memory is bad lol I assure you mine is worse, what am I building Thanks for the update. Can you also take a look at F3 because this cannot be right...... It is as if the bulkhead is too narrow at the top....... The measurements match the plan.. Maybe I am too stupid to make model planes Quote Link to comment Share on other sites More sharing options...
Hugh Coleman Posted October 29, 2010 Share Posted October 29, 2010 That looks pretty similar to what I got with the 62" as well. Remember that you will be sanding and planing the bezeejus out of after all the assembly to get the required shape. You will be sanding/planing well into the triangle stock before you are happy with the profile... I did on the 62" one. Lite weight filler can hide a multitude of errors. Cheers, Hugh. "Over the wings,... flood the coweling!... OK, Stand Clear!" Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 29, 2010 Author Share Posted October 29, 2010 Hi Hugh, I would have expected a gradual curve from the square firewall through to the cockpit and back. There is a massive kink at F3, no amount of sanding is going to help that. The triangular stock is cranked over so far it doesn't even meet the upper surface so wont even be there to be sanded. I might undo it all and make a new F3 bulkhead. I don't mind hiding errors if I must, but I would first like to know what the error is....... Cheers Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 29, 2010 Author Share Posted October 29, 2010 Amazing how a small change can make such a difference. I broke the joint at the top of the fus (at F3) and just let the gap open a bit, about 3mm. the other side needed slightly more drastic work because all the triangle section had broken from the bending. This was again broken away at the top of F3 and the triangle section removed. The outer sheeting was again allowed to relax and leave a gap to the bulkhead. New triangle stock was let in and the gaps made good. Those following on I would seriously think of doing as Hugh did on the earlier 62" and that is leave the triangle stock until after the sides are curved and attached to the bulkheads. If nothing else it will give you something to allign the triangle to, because doing them first you have no reference. Anyway, some of the scruffiest work I have done, but its solid and I am happier with the lines now. Tally Ho! "I thought you would come out of the sun..." Quote Link to comment Share on other sites More sharing options...
Hugh Coleman Posted October 29, 2010 Share Posted October 29, 2010 The triangular stock is cranked over so far it doesn't even meet the upper surface so wont even be there to be sanded. I might undo it all and make a new F3 bulkhead. Ah, yes, remember I said that the triangle stock protruded from the top of the side sheets after I had installed it? Actually, just enough to sand off to a flat surface to take the block of... 12mm sheet it was on the 62" version I think. Which would seem to indicate that the bulkhead was right to start with. Sorry. Cheers, Hugh Don't just think boy, Search for the bastards! Edited By Hugh Coleman on 29/10/2010 10:38:27Edited By Hugh Coleman on 29/10/2010 10:39:16 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 29, 2010 Author Share Posted October 29, 2010 Hi Hugh, please don't appologise, I really appreciate your thoughts. I have never built one of Tony's designs so am only too pleased to hear from those that have. Cheers Danny "And never fly in a straight line or your'e a dead duck" Quote Link to comment Share on other sites More sharing options...
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