A.A. Barry Posted October 25, 2014 Author Share Posted October 25, 2014 Thank Danny, my laser guy here in Aus, has excelled himself this time round, B Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted October 25, 2014 Share Posted October 25, 2014 I had to tickle a few formers when I checked with a long rule but I had put that down to me cutting the parts. The fuzz I am happy with, once wing fairings and servo tray/bearers are added I reckon it'll be o.k. The engine bearers I ignored, will build a ply box ala Danny but for I.C, some strength will be added with light glass cloth. Unusual for me not beefing things up i'm quite chuffed with that John Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted October 25, 2014 Share Posted October 25, 2014 Why not use the rails John simple and works for ic ? Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted October 25, 2014 Share Posted October 25, 2014 Yes Danny, but it's one of my quirks (I have a few) I prefer the mount, I am fussy about getting the engine thrust right for flying... I sand back off the mount till i'm happy they fly right. My version of OCD maybe ? John Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted October 27, 2014 Author Share Posted October 27, 2014 After the doublers had a chance to dry I started planking, the lower fuz, after some thought i opted to make the strips 3/8" one end 3/16 " other end, but before I started I added te elevator nyrod, I reacon that tapering the strips will help with the overall finish of the job the planking is 2" short of 36" sheet so that piece was just sheeted in one pioce, at the ft..... so 1 side done Baaa Edited By A.A. Barry on 27/10/2014 09:52:57 Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted October 31, 2014 Author Share Posted October 31, 2014 So the wing, centre section tackled by way of it being seperate to the panels first off, Iv'e added more R1 ribs each side of the suggested plan position,they are just inside the plan position, and when the panel is slipped in, hey ho epoxied together, these are really just to keep the whole centre in line.The braces B2 will be glued to them and the wing spar packers will be slotted in after the a panel is "fitted up. The L.E of the ribs will sort of swing free during this stage and a couple of spacers between W1, W2 and W3 will over come that and can be cut away after it's all glued up. B1 will increased in size to match up with the rib sizing at the ft..and sanded to suit later.... any way a couple of pics for a better idea Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 1, 2014 Author Share Posted November 1, 2014 Ok, the centre section now ready to attach the 1 panel, I blocked up the section so that thelower spar is flat on the board with the rear part of W1 rib also flat on the board, so then added W2 and 3 with the rear spar also flat. The drawing on the plan in regards to B3 and B4, I found to be a little confusing, as it shows an inverted view and i am work right way up, 2 attempts at that. From here on in the build should progress as normal Cheers Baaa Edited By A.A. Barry on 01/11/2014 10:41:11 Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted November 1, 2014 Share Posted November 1, 2014 You're moving along nicely Barry John Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted November 1, 2014 Share Posted November 1, 2014 More good ideas. Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 1, 2014 Author Share Posted November 1, 2014 Thx John and Colin, you blokes are doing well also If I understand the plan right, one is supposed to pack out the space in between the spars on B2 brace, I wonder why Dennis has done this, surly the ply is enough at this point, if there is a weakness in the wing, it will break outside the brace, if anything a little more webbing on the brace between W2 and W3 Baaa Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 1, 2014 Share Posted November 1, 2014 Posted by A.A. Barry on 01/11/2014 20:01:54: If I understand the plan right, one is supposed to pack out the space in between the spars on B2 brace, I wonder why Dennis has done this, surly the ply is enough at this point, if there is a weakness in the wing, it will break outside the brace, if anything a little more webbing on the brace between W2 and W3 Do you mean the small ply rectangles Barry, I think it all to do with a gradual change in strength? I am concerned about you using the trailing edge as your reference and keeping it flat on the board, that doesn't sound right as the trailing edge will rise from against the board to 3mm elevated as Nigel has shown. Cheers Danny Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 1, 2014 Author Share Posted November 1, 2014 Danny, when you say "small rectangle pieces" I'm not to sure by which you mean, I must have missed that bit about the T/E rising in Nigel.s build Thx Barry Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 1, 2014 Share Posted November 1, 2014 You talk about packing out the space between the spars on B2, I probably have not understood what you mean? Yes the trailing edge will rise, this is why I added the jigging tabs to the bottom of the ribs to allow for this. Nigels wedge shaped piece that is 3mm at the root (R1) and 6mm at (W18) will achieve the same thing. The only reference you can use is the lower spar without packing up the trailing edge. If you want to add a couple of degrees of washout then, make the tip perhaps 8mm?? Remember that if you build the ailerons flat the washout will mean the ailerons will droop at the tip when flush with the flaps. Cheers Danny Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted November 1, 2014 Share Posted November 1, 2014 Sorry I can't add anything constructive chaps, too far away at the moment! Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 2, 2014 Author Share Posted November 2, 2014 Ahhh, well if I cut a piece of sheet (1/4" ) and taper it from 3mm to 8mm, place it under T.E should be ok then ?? ( I prefer wash out, usually +2 deg ) . My plan didn't show tabs on the ribs, an added bonus for those who cut their own.... hey , they are great help As for the ailerons, I will take a measurement at that spot and build them accordingly to the taper Thanks Danny Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 2, 2014 Share Posted November 2, 2014 Hi Barry, 3mm tapered to 8mm sounds a good guestimate. No the plans do not show the tabs, that was something I showed in my wing build.... Cheers Danny Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 2, 2014 Author Share Posted November 2, 2014 Ahh yes Danny I recall seeing that post now, of course I forgot all about when i started the wing build, any way I have taken your advice and packed up the T/E, 3mm at W1 and 8mm at the tip, I added the L/E and the main spars, sheer webs glued and a triangled strip added to the top of the T/E to carry the flappy bits shroud, do I do the same to the lower of T/E, for a flap shroud ???? Till tomorrow Baaa \ Edited By A.A. Barry on 02/11/2014 12:11:04 Edited By A.A. Barry on 02/11/2014 12:12:08 Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 2, 2014 Share Posted November 2, 2014 Hi Barry I just use 1/8 sq but triangle would have given more wriggle room.CheersDanny Quote Link to comment Share on other sites More sharing options...
AlexJ Posted November 2, 2014 Share Posted November 2, 2014 Hi Barry/Danny, I have just been faffing in the workshop, about to start the wing. Just out of interest, I was working out what the incidence was for the wing. I decided to do the spanwise tapered packer thing for supporting the ribs, the gap under the TE of the ribs is 6mm at rib No.1 and 3mm at rib No.18. Shouldn't we add a bit at the tip, say 1-2 mm, say 6mm at No.1, 4 or 5mm at No.18? My concern is, there is only 1.25 deg of positive shown on the fuselage side view, at root. With this relative difference (8mm at tip, 3mm at root) the tip has a lot of negative incidence. Hope I am wrong. Alex Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 2, 2014 Share Posted November 2, 2014 Hi Alex, "the gap under the TE of the ribs is 6mm at rib No.1 and 3mm at rib No.18." the taper should be thicker at the root than the tip, just to allow for the reduction in distance from the spar. But I think you might be right the taper theory that Nigel did may have the wrong numbers. If you measure back 70mm from the spar at R1 and at R18 the distance to the datum will be the same 3mm. However because R1 trailing edge is 115mm from the spar the height is greater at 6mm. Just thinking out loud then, to build a wing as Dennis has drawn, which appears to have no washout. A wedge 6mm at the root and 3mm at the tip is required under the rear of the ribs. If we want some washout then the tip number needs to be greater, this obviously will mean the number increases progressively along the wedge as it is a straight taper. I arbitarily added 2mm at the tip as a guess. This will mean that the height will alter at the intermediaries as you say. Cheers Danny Quote Link to comment Share on other sites More sharing options...
AlexJ Posted November 2, 2014 Share Posted November 2, 2014 Danny, When I checked the neutral or centreline of the airfoil (not sure of correct term), on the rib drawings, they do seem parallel, to the datum line DB has shown. This does indicate no washout, as you say. I think I will leave my wedge as I have cut it, 6mm at root, 4mm at No.18, it does not sound much, it adds 1deg of washout. I like the idea of getting things right, trying to be accurate, but I do wonder how much difference, up to a point, this all makes. Alex Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted November 2, 2014 Share Posted November 2, 2014 As far as I'm concerned the sequence of events for me will be this:- Check that tailplane incidence is at zero to fuselage datum, if not change it so it is. Set wing root incidence at plus 3 degrees to the fuselage datum. Draw wing tip rib at minus 2 degrees negative relative to the root incidence i.e. 1 degree positive. From that determine the height that the trailing edge of the tip rib will be above the original zero position and draw a straight line back from that to the root rib. Measure the relative difference between the height of that line relative to the zero line at each rib position. Use those measurements to make the tab for attachment to each rib so that are all set to give the progressive straight line variation from zero mm at the root to the calculated height at the tip rib trailing edge which gives the required 2 degrees negative twist, I.e. Wash-out. This will give a mean angle of wing incidence of 2 degrees and a wash-out of 2 degrees. I'll need to look at whether any change to the thrust line is necessary when I look at the plan. I reckon that sums it up for me. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted November 2, 2014 Share Posted November 2, 2014 Hi Colin, not saying you are wrong, but I guess that means you aren't building a Bryant Chippy Nobody has said these do not fly well why change it? Seems a lot of work to me. And who knows with this wing section it isn't better this way? I know we have complained about the plan a bit, but I am still of the belief that Dennis is no fool and knows a thing or too Cheers Danny Edited By Danny Fenton on 02/11/2014 21:38:10 Quote Link to comment Share on other sites More sharing options...
Colin Leighfield Posted November 2, 2014 Share Posted November 2, 2014 Danny, there's no right or wrong in it and I don't question that it flies ok as Dennis designed it, it's just my preference. As I haven't started on wing or fuselage yet it's very little extra work. You used tabs on the ribs anyway so it's the work of minutes to make the difference I suggest here. Visually I doubt if anyone will notice but I think it will be very interesting to see if there are any noticeable differences in flight characteristics between otherwise similar airframes. I'm not trying to persuade anyone else to do it, but all of this interests me and I have a personal view that wash-out is beneficial in more than one respect so I want to do it. Also it's getting closer to the full-size. Don't forget that I'm sticking Depron in here and there as well, although I'm working off the plan and using the pre-cut wood parts from Traplet. However, if you think this is drifting too far from the principle of the thread I can put it in another thread? What do you think? Bear in mind that converting from I/c to electric requires bigger changes to the design than adding 2 degrees of wash-out. Quote Link to comment Share on other sites More sharing options...
A.A. Barry Posted November 2, 2014 Author Share Posted November 2, 2014 Well, well,.... well an interesting debate, do I continue on with my 3mm root and 8mm tip, guys ????? Baa Ram Quote Link to comment Share on other sites More sharing options...
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