Peter Miller Posted February 8, 2016 Share Posted February 8, 2016 Just found this one. Don't forget, the tailplane actually should butt up against F-10. Don't ask, because I don't know Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted February 8, 2016 Author Share Posted February 8, 2016 Peter, is there any reason - other than appearance - that it should butt against F10? I had intended moving it just far enough forward for the elevator joiner to clear the rudder hinge line. The tailplane platform does a pretty good job of locking the rear together on it's own. Quote Link to comment Share on other sites More sharing options...
kc Posted February 8, 2016 Share Posted February 8, 2016 Further back may require a wider V cutout in elevator to get maximum rudder - perhaps? Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted February 8, 2016 Share Posted February 8, 2016 Only the fact that I designed it that way. If you want to leave there feel free. Oh and it will be a fraction stronger Quote Link to comment Share on other sites More sharing options...
kc Posted February 8, 2016 Share Posted February 8, 2016 It's a neat design which avoids having a hole in the rudder for the joiner. As designed it seems that there is enough space that a hardwood joiner could be used instead of piano wire. ( I hate piano wire joiners! ) Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted February 8, 2016 Author Share Posted February 8, 2016 kc - you can do that without moving the tail all the way forward and leaving a gap behind the ele to be either filled with scrap or ignored. I've trimmed the fuselage sides by about 5mm which leaves a little wiggle room for the joiner without any obtrusive gap. Who knows, by the time I get around to fitting the elevator I might have changed my mind - again. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 5, 2016 Author Share Posted March 5, 2016 OK, I haven't abandoned the Ballerina, it's been a little spurt now and then. There's plenty of construction photos on other builders threads so here's a description of where I went my own way. As the plan only shows one wing panel I took the lazy option for the second panel. I drew in the positions for the spars and aileron for the second wing and built it back to front on the plan. Simples. First I pinned down all the 1/16" sheet - LE, TE and all cap strips, marked the rib positions on them and assembled the lower spars and ribs directly on the sheet. Then I positioned the completed wing with it's dihedral brace and glued in the second panel R1 segments, leading edge and top spar all butting against the first panel. I could then lift off the complete panel and add the second panel's upper sheet etc. before finally joing the two panels together with a perfect butt joint at the root. For the U/C blocks, I pre-drilled them and marked the line of the hole on the side of the block. I had drawn centre lines on the U/C plates beforehand so when fitting the blocks I could just line up the centrelines confident that the hole would line up with the groove in the plate. Before adding the top sheet I ran a 4mm drill through the U/C plate and lower sheet using the block as a drill guide. OK, it left a 4mm hole in the plan and building board, I can live with that. Fin fairing blocks - I made up an inverted T from 1/4" scrap and a couple of lengths of 1/4"sq to use as a spacer and alignment gauge. With the T pinned in place and carefully lined up along the fuselage centreline I glued the blocks in place. being careful to only get glue on the joint with F10. I shaped one side at a time while the other side I kept pinned to the fuselage to hold everything steady. Now I have a kit of parts, just a cowl to concoct before I start covering. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 5, 2016 Author Share Posted March 5, 2016 and yes, I did mess up the stringer spacing on F10. One thing I noticed is that the wing chord is 2 or 3mm greater than the length of the wing seat so the TE will rest up against the bottom of F6. I added a strip of 1/4"sq across the junction of F6 and the lower sheet to provide some support. Another point is that the wing bolts are shown as vertical on the plan which puts them at an angle to the lower surface of the wing. Bad. I redrew them at 90 degrees to the wing underside and adjusted the position of the bolt plate to match. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 5, 2016 Share Posted March 5, 2016 Ah cover before you fit tail end, very sensible, it took me ages to cover mine all built up. Not be long now Bob John Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted March 5, 2016 Share Posted March 5, 2016 Interesting to see the different covering methods! I prefer to cover the airframe and tail all built up and the control surfaces separate. I too drilled the wing bolts at 90 degrees to the underside of the wing. I suspect the draughtsman has simply drawn them vertical! Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 6, 2016 Author Share Posted March 6, 2016 I used to assemble the airframe before covering, but the Thunderbird reminded me what a pain it is trying to get a neat junction between tailplane/fuselage, rudder/fuselage etc. without the covering pulling away from one side or the other. If ARTFs have taught me one thing it's how much easier it is to pre-cover everything. It also makes it easier to do the fiddly bits like the snake exits with 360 degree access. Amazing how much time can be spent on all the little things - separating the ailerons and shaping the hingelines, planning the cowl construction (whack on some 1/2" sheet and hack off the excess?) and mountings, checking the tail surface alignment, trimming away the bottom sheet for the U/C wire and mountings - a full day yesterday and the only thing to show at a glance is that the ailerons are separate now. Quote Link to comment Share on other sites More sharing options...
Former Member Posted March 6, 2016 Share Posted March 6, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 7, 2016 Author Share Posted March 7, 2016 TopFlite sea Fury TopFlite Corsair DirtyBirdy 40 Sig Liberty Sport PM Melody North Yorks Models Extra 230 Pica Jungmeister Take your pick Brian. Quote Link to comment Share on other sites More sharing options...
AndyD Posted March 7, 2016 Share Posted March 7, 2016 that will keep you busy till summer then what lol,would have to be the corsair or jungmeister next for me. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 8, 2016 Author Share Posted March 8, 2016 I missed out - finishing off the Thunderbird! Quote Link to comment Share on other sites More sharing options...
Martyn K Posted March 8, 2016 Share Posted March 8, 2016 Posted by Bob Cotsford on 05/03/2016 11:47:29: and yes, I did mess up the stringer spacing on F10. One thing I noticed is that the wing chord is 2 or 3mm greater than the length of the wing seat so the TE will rest up against the bottom of F6. I added a strip of 1/4"sq across the junction of F6 and the lower sheet to provide some support. Another point is that the wing bolts are shown as vertical on the plan which puts them at an angle to the lower surface of the wing. Bad. I redrew them at 90 degrees to the wing underside and adjusted the position of the bolt plate to match. Yep - I noticed both of those and mine were magnified by 15%. My wing also doesn't seat properly at the TE. I did consider trying to fair it in with a wedge of balsa on the lower fuselage behind the TE but decided that wouldn't look right either. I mitigated this by deciding that I couldn't see it when it was standing on its wheels. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 8, 2016 Author Share Posted March 8, 2016 I've used 3/32 sheet under the rear so after trimming it to clear the wing the T/E now seats on the bottom of the former and sits flush with the sheet, but you are right - out of sight, out of mind. As long as it stays rubber side down Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 8, 2016 Share Posted March 8, 2016 Mine fits lovely, in fact it looks better upside down John Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 8, 2016 Author Share Posted March 8, 2016 And now to see a considerable volume of balsa reduced to shavings - the cowl! 1/8" sheet forms the outer side,with a 1" wide strip of 1/16" ply for reinforcement where it will screw on to the fuselage. This is built up with some soft 1/2" sheet that has been kicking around for 10 years or more looking for a home. This layer needs relieving to clear the mounting blocks, needle valve and throttle linkage. 1/4*5/8" ply strips epoxied to the engine bulkhead form the mounting blocks. With the ply nose ring attached to the back of the spinner using double sided foam tape I got the sides trimmed to length and glued to the nose ring. Then it's just a matter of filling in bits where cowl is needed with more 1/2" sheet and miscellaneous bits out of the scrap box. Just the top and some infill on the bottom to go on then i can start whittling. I've counterbored the screw positions so that the mounting screws will be sunk into the finished cowl biting directly on the 1/16" ply. Edited By Bob Cotsford on 08/03/2016 20:43:32 Quote Link to comment Share on other sites More sharing options...
Craig Thomas Posted March 8, 2016 Share Posted March 8, 2016 I'll be watching this cowl with great interest. Still pondering how to do mine. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 9, 2016 Author Share Posted March 9, 2016 There are other ways of doing it Craig. One alternate option would be to go for a less curvaceous shape by using flat sheet sides, rolled sheet top and a 1/2" sheet plate at the front that can be given a bit of shape. Outline formers (ie the centres cut out to clear the engine and mount) would hold the sides and top in shape at the engine bulkhead end and the back of the 1/2" front sheet. Meanwhile I'm ready to remove the engine and create a small mountain of wood chips. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted March 9, 2016 Author Share Posted March 9, 2016 A face only a mother could love? Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted March 9, 2016 Share Posted March 9, 2016 It looks like Grommit Bob nicely done though John Quote Link to comment Share on other sites More sharing options...
McG 6969 Posted March 9, 2016 Share Posted March 9, 2016 Well, for me it looks more like a Tempest or a Typhoon cowl... But my 'mom' would love it anyway... Well done, Bob. Hakuna matata Chris BRU - BE / CTR Grommit Control Quote Link to comment Share on other sites More sharing options...
Chris Barlow Posted March 9, 2016 Share Posted March 9, 2016 That's very nice Bob! Some proper carving and shaping there. Wouldn't like to cover it with film though! Out of interest how much does it weigh? I was thinking I had increased the nose weight on mine too much with the GF cowl. Quote Link to comment Share on other sites More sharing options...
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