Mike Hardy Posted July 20, 2012 Share Posted July 20, 2012 Hi, the Junior 60 wing dihedral is 11.5 deg which means the 1st rib has to be set at this angle ie 101.5 deg to the horizontal. Please advise the best way in achieving this. Measure the angle with the wing panel horizontal or set the rib at 90 deg with the panel elevated at the tip (6". Thanks for any guidance, Mike. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted July 20, 2012 Share Posted July 20, 2012 In t' olden days plans would come with a template that allowed you to set the root rib at the correct angle with the rest of the wing pinned flat to the board. The template would be cut from ply or card & held against the root rib to set the angle...... I think either of the methods you describe will work OK....dihedral on a Junior 60 will not be that critical....so long as it's around 6" you will be fine.... Quote Link to comment Share on other sites More sharing options...
kc Posted July 20, 2012 Share Posted July 20, 2012 You should set half the angle on each wing panel. Draw wing half span on piece of wood, bench or paper and then measure up the amount under each wing tip ( half the total dihedral ) and draw another line. Draw a vertical line and this is the angle for each wing half panel. You can then make a balsa or ply template or set a sliding bevel gauge to the angle. Make inside or outside template or both. Probably make an outside template in ply and also a 1/4 balsa inside template to pin to rib. Its often better to build the second panel onto the first to avoid an error occuring. Especially so for models with a flat centre section, build a panel then build the centre section onto it, then the second panel.onto it. Quote Link to comment Share on other sites More sharing options...
Mike Hardy Posted July 20, 2012 Author Share Posted July 20, 2012 Ah KC, Dihedral - I thought this was the wing tip elevation from the horizontal for each wing panel. From your comments then Dihedral is the total elevation for both wings or angle to the horizontal. Must google this term. very confusing for a beginner!! Mike. Quote Link to comment Share on other sites More sharing options...
kc Posted July 20, 2012 Share Posted July 20, 2012 Sometimes a plan might say 3 inches under each wing tip ( Just an example ) or total 6 inches dihedral. This is the same of course. . It's much easier to measure it this way rather than in degrees because a slight error will be magnified at the wingtip. However you must start by putting the root ribs at the correct angle, and later when joining the panels there might be a slight gap ( top or bottom ) between the root ribs, in this case a sliver of balsa is used to fill the gap. Also the ply wing joiners ( if any ) will set the dihedral. If you put one root rib at the full dihedral angle and one at 90 degrees the wing span will be slightly different on each panel if the spars are equal length, so put half the angle on each rib Check which version of the plan you are using because it's possible people use less dihedral for RC models with an elevator than for free flight. ( sorry I have not built a Junior 60 so dont have the plan ) I think Ben Buckle re-drew the plan for RC and i would follow his plan rather than the original. Quote Link to comment Share on other sites More sharing options...
Mike Hardy Posted July 23, 2012 Author Share Posted July 23, 2012 Thanks kc, as there is a horizontal section of wing that joins the two panels together I have set each root rib at 90 degrees whilst the wind tip is elevated by 6". The drawing for each wing panel is slightly different!! ( 1/4 inch) so I am going to follow your advice advice and build the second panel 'on top of' the first. Will post some pics of progress, by-the-way do you have to use a photo host like photobucket to post pics on this forum.? Mike. Quote Link to comment Share on other sites More sharing options...
Ben B Posted July 23, 2012 Share Posted July 23, 2012 I always leave the inner ribs unglued, prop up the wings (to give the required dihedral) then glue them in. But yes, be careful, some plans talk about the height under both wingtips, others assuming one wing is being built on the bench and the dihedral is the gap under one wing which isn't the same as 2* the gap under both wings when it's in a V position. Been there, done that. Quote Link to comment Share on other sites More sharing options...
kc Posted July 23, 2012 Share Posted July 23, 2012 Ben is right. I suggest building the first panel onto the centre section but wing joiners only clamped not glued then build second panel the same. Finally glue centre section with both wings propped up the same with centre section horizontal. To get both panels at the same dihedral! Do check what dihedral is recommended on RC models. No you dont need Photobucket, but they must be JPEG files. I just load them to Modelflying - My Photos- New Album- Browse- then your file. Takes a minute or two for the OK sign to come up, which you then press to upload. ( from memory-- it's something like that! ). I always reduce photo files to a small size in PhotoShop so they load quickly. Quote Link to comment Share on other sites More sharing options...
David Hooper Posted September 20, 2017 Share Posted September 20, 2017 Hello everyone, I wrote asking for help a while ago as I am new to this plane lark and you were all great, well I am getting along quite well taking my time and making mistakes but learning as I go along. My question is this, I have got the wing section pinned down (not glued!!) and they have supplied me with a dihedral template which is a square with a corner missing. Now what I need to know is how do I use it where do I use it on the inner wing rib.A bit like a virgin I know where it is and what it is but not how to use the damn thing. any help would be appreciated Regards Dai H Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted September 20, 2017 Share Posted September 20, 2017 Edited By Denis Watkins on 20/09/2017 16:07:28 Quote Link to comment Share on other sites More sharing options...
Stevo Posted September 20, 2017 Share Posted September 20, 2017 Dare I say SohCahToa to get the angle Quote Link to comment Share on other sites More sharing options...
Gary Murphy 1 Posted September 20, 2017 Share Posted September 20, 2017 Not many builds to my name yet and on a early unpowered glider I forget to set the dihedral on one wing,the first. So I ended up putting all the required angle to the last wings rib root. This worked out ok,would this be a acceptable way in the future? Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted September 20, 2017 Share Posted September 20, 2017 It's not ideal but there's little harm in doing it. The dihedral brace or wing joining system sets the dihedral in reality - the wing root ribs contribute little or nothing to the strength of the structure and serve mainly to support the skin or covering material. Edited By Martin Harris on 20/09/2017 17:42:39 Quote Link to comment Share on other sites More sharing options...
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