Robert Edney Posted January 27, 2018 Share Posted January 27, 2018 Just finished the first half of the wing and when I removed it from the board it has a bit of a bend, will this be OK or is it basically ruined??? Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted January 27, 2018 Share Posted January 27, 2018 Rob Its going to be a bit difficult if, as a beginner, you start a different thread for every problem or question that arises without any reference to the model you're building, a picture, etc. It would be easier for the more experienced hands to offer you help and advice if you start a single thread titled, say, 'Beginner's First Model, XYZ Glider - Help Appreciated' then raise each new issue as you encounter there for continuity. Jon Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted January 27, 2018 Share Posted January 27, 2018 Jonathan is right, it is much easier for us to help you if everything is in one place. That way we know the history and we build up a set of photos of your progress, so we get a good idea of what will work. Regarding your warp problem, we need a picture, and we need to know how big this is, very small warps can be trimmed out, slightly bigger can sometimes be fixed, otherwise it's the bin and one to put down to experience. But without seeing it and some idea of the extent we can't say which it is. Also, you say "warp", then you talk of a "bend". Is it a bend or is it a twist?Post some pictures and a bit on the scale of the problem and I'm sure we can help.BEB Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 Well to be honest in a beginners thread I thought help appreciated was implied, and if there are any specific models out there that a warped wing isn't a problem let me know, that would be appreciated Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted January 27, 2018 Share Posted January 27, 2018 Woops, let's start again Wood, being a natural material, is all "wood" , but every single piece is different, made up of cells that grew in all manner of temperature and humidity, light and dark etc etc etc So it is quite common to have some shift on removal from the board, and it is not ruined. In the olden days, artisans put there timber into the room where the future furniture would live, one or two years before the furniture was built because wood can swell across the grain as well as stretch 20% longer with moisture Observe and mark in a way that you can identify, tape pin etc the bend. Back on the board, warm the parts up with an hairdryer and observe if it decreases or increases If the bend decreases, heat longer If the bend increases, turn over and warm the other side Or leave it until covering Covering varies, but usually we cover the underside first Brace the wing and cover what was the underside, has it improved? The cover the rest, straight as you go Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 Modern tech drives me insane, finally got a not very good pic uploaded, hope it helps, the from of the wing is not as bad as the trailing edge. And I was so proud of myself until I removed it! Quote Link to comment Share on other sites More sharing options...
brokenenglish Posted January 27, 2018 Share Posted January 27, 2018 Robert, it depends on what your criteria are. Obviously, the trailing edge shouldn't be like that but, to be honest, I don't see anything that will stop the plane from flying. You'll be able to "trim it out" in flight. One amusing possibility would be to try to build the other wing the same Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 Thanks that is what I was hoping to hear, I built it on a bit of plaster board and I think a little bit of something got underneath, that part of the plan is still a usable so in theory I could make the opposite wing the same, if it was all down to a bent board.☺ Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted January 27, 2018 Share Posted January 27, 2018 I agree with Brokenenglish - if what we see in the photo is all of it, then you should be able to sort that at flight time. Build the other one as straight as you can, then allow a little individual aileron trim on the affected wing, using two aileron servos on separate channels will make that easier. BEB Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 Unfortunately there are no ailerons on this model, embark 2-3 channel beginners glider, just rudder and elevator! Still practice makes perfect, Quote Link to comment Share on other sites More sharing options...
Don Fry Posted January 27, 2018 Share Posted January 27, 2018 I might be tempted to make it straight. It will fly like that, but not well. And if the straightening does not work, a new panel to make is not the end of the world. I would be reluctant to go ahead with the build, knowing it's got a problem, so early in the build. It's a sick feeling in the gut for the rest of the build, wondering if you are wasting more time. Pin the straight sections of the panel to the board. Then cut, with a razor saw through the wing ribs in the bent area, where they go into the spar web. Then pin the trailing edge down so it's all flat. You will now have a gap at the top of the sawn section. Reglue the ribs to the spar web, using triangular section. Hint, make the triangular section 3mm short, top and bottom, so when you cover it, the bodge disappears and it looks perfect. No guarantee it will totally get rid of the problem, but I would bet it will get rid of most if not all the problem. Wing ribs are not high stress bits in a wing, the triangular section need only be a bit of 3mm, or at biggest 5mm, so not much weight added. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted January 27, 2018 Share Posted January 27, 2018 Hi Robert, I'm sorry if I came across a bit full, was just trying to be constructive in the absence of background info. Useful to see the photo and know what sort of model it is. I'd certainly try to rectify the problem (as a beginner you don't need any unintended aerodynamic effects due to warped surfaces confounding your attempts to fly straight and level let alone turn etc). Don's 'cut-and-re-glue' method makes excellent sense to me. Another method, which people use with smaller and much lighter balsa and tissue-covered rubber powered scale models, it to 'bully' a warped wing flat. Steam the whole balsa structure over a kettle or pot of boiling water for a while (but not so brutally that the glue-joints start to come apart!), then pin flat on the building board and leave to dry overnight. If this doesn't work, i.e. you get 'spring-back' to some or all of the original warp, then steam again but this time use thin balsa shims under all the parts except those you want to bend down a bit further, then pin the whole lot down again and leave to dry. If you judge it right, then the spring-back will hopefully result in a more or less un-warped wing. Then cover. Jon Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 I was thinking about the steam as I have seen people shape wood using that method but was worried about the glue, I think I will give it a try because I really don't want to start hacking it up. I was thinking about building two towers to put under the wing tips gets nice straight bit of 4x2 on the top of the wing to level it and then get at it with the steamer, might work, I don't think I can make it worse. But you never know!! Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted January 27, 2018 Share Posted January 27, 2018 Worth having a go at straightening it, careful though or you might end up with little warps in the sheeting, seen much worse that flys o.k though. Quote Link to comment Share on other sites More sharing options...
Don Fry Posted January 27, 2018 Share Posted January 27, 2018 Bit of an improvement to the bodge, wet the bent bit of trailing edge when you pin it down. As it dries, it tends to take it's new shape. Don't get discouraged. And when you look in envy at a masters model, just remember he is a devious hider of mistakes. I once had lessons from a good builder. Arrrrrr he would say, but can you see what I have done when the job is finished. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted January 27, 2018 Share Posted January 27, 2018 One thing that no one seems to have mentioned is the twist. A bent wing without any twist is not really a problem. Pin the wing down upside down and then put a strip of wood or ruler across the wing at the root and the tip. Sight along the wing. If they are parallel you do not have a problem. If they are not you have a warp but even this can be removed fairly easily. I KNOW because I found the way to do it easily in the past. If you have a twist or warp on a wing with leading edge sheet top and bottom it will resist twisting BUIT here comes the clever bit. Run a scalpel down the top leading edge sheet from root to tip about three times. More for a wide wing. Set the wing up on the board with just a hint of reverse warp on it and run CA glue into the slits. Instant cure.. I know it works because I have done it more than once in my life Quote Link to comment Share on other sites More sharing options...
Don Fry Posted January 27, 2018 Share Posted January 27, 2018 As many bodges as builders. Quote Link to comment Share on other sites More sharing options...
John Stainforth Posted January 27, 2018 Share Posted January 27, 2018 Like so many things in aeromodelling (and most things), preparation is key. In the same vein as "measure twice (or three) times and cut once", it really pays to select the wood for the wing spars carefully. Someone who has strongly advocated that is Dave Platt in his really useful videos. It takes very little time to match the wood for spars, port and starboard, top and bottom by their straightness and bending behaviour. The same goes for the wood used for sheeting. Symmetry is everything, as is having a true building board and holding everything where it should be while the glue dries, whether you are using pins or magnets or weights. I favour weights, and back copies of RCME are perfect for weighing wings down, as long as the wing structure is jigged accurately. Quote Link to comment Share on other sites More sharing options...
Robert Edney Posted January 27, 2018 Author Share Posted January 27, 2018 Trust me I done all that as it was my first one and the instructions might as well been left out as the complete build was explained on one and a half A4 sheets of paper, after closer inspection the bend on the leading edge was caused by the glue letting go on the ribs, I have re-glued that and the leading edge is now looking good. Well we will see tomorrow, if it is I was thinking I might just try to carefully cut off the last few ribs,on the trailing edge it might let it stretch out, you know sort of try to unglue them if you like, if I'm gonna cut it I want to try and keep it as tidy as possible, Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted January 27, 2018 Share Posted January 27, 2018 Posted by Don Fry on 27/01/2018 19:11:10: As many bodges as builders. Nowt wrong with a good bodge BEB Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted January 28, 2018 Share Posted January 28, 2018 Difficult to tell from the photo perhaps but is the main spar bent, because that is difficult to fix? The trailing edge is not so much of a problem hopefully. I agree with Don, just wet it and tape it down with some opposite bend in and leave to dry. Steaming will do the same but breaks down some of the fibers in the wood so possibly more effective. Ammonia (in a well ventilated room) has the same effect on the wood. Don't worry if some of the wood comes unstuck, it can be re-glued. It is a bit trial and error unfortunately but comes under the heading of 'fettling' rather than 'bodging' in my book. Good luck, we have all been there, as it is the nature of the material we are working with. Quote Link to comment Share on other sites More sharing options...
Glyn44 Posted January 28, 2018 Share Posted January 28, 2018 Your right BEB. Nothing would get finished, in this house, without a bode otmtwo. Part of the builders craft. Quote Link to comment Share on other sites More sharing options...
Former Member Posted January 28, 2018 Share Posted January 28, 2018 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted January 28, 2018 Share Posted January 28, 2018 I once got a prize at our club AGM for a particular season of building wings etc with warps in!!!....yee gazooks I hear you all cry-but if its not too bad-I wouldn't worry about it...... ken Anderson...ne..1..... warp dept. Quote Link to comment Share on other sites More sharing options...
Jimbo565 Posted January 28, 2018 Share Posted January 28, 2018 I bet it was Warp factor 2 JC....ne23....factor2 dept. 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.