Tim Ballinger Posted November 30, 2017 Author Share Posted November 30, 2017 Quick win here with the 1/4 sheet tailplane. Rear fairing added withe aid of dummy fin and tailplane which also serves as a support to save damage to the rear fairing prior to fitting the fin & tailplane after covering later on. A technique known to many but I only picked it up during last years mass build ! Tim Quote Link to comment Share on other sites More sharing options...
Lucas Hofman Posted December 1, 2017 Share Posted December 1, 2017 Small motors to run such big propellers. Your results are close to the nominal specs, so when cooled well they should survive. How do you measure the static trust? Lucas ps. Tempted to start with a tigercub, but really should finish the other 2 first.... Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 1, 2017 Author Share Posted December 1, 2017 Two methods. 1. lashed up a plywood boom and mounted the two motors. Attached the boom to a central rod running along the centre of a workmate bench. G Clamps hold a restraint above the rod to stop the whole thing pitching. Attached a spring balance to the rod and a fixed support behind the bench. At full throttle release the clamps on the workmate holding the rod and read the balance. Had a lot of ‘sticktion’ but I only wanted a rough static reading. That gave me a reading of @ 4lbs. 2. Sent all my results to George at 4 max who confirmed he had measured the static thrust of my setup at 2.9 lbs per motor ie 5.8 lbs total and comfortingly , higher than my measurement. Not seen George’s test rig but you can bet it is better than mine ! Should have taken some pics but taken it all apart now. Tim Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 1, 2017 Author Share Posted December 1, 2017 .....and I used the Telemtry on my HiTec to measure the current/ wattage. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 1, 2017 Author Share Posted December 1, 2017 Added some flappy bits. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 4, 2017 Author Share Posted December 4, 2017 Always like to check all the gear fits at an early stage . Fitted battery/esc/connectors to create the wiring harness for the fuselage and no denying it’s tight but I think it will be ok. Quote Link to comment Share on other sites More sharing options...
Lucas Hofman Posted December 4, 2017 Share Posted December 4, 2017 Very much so. Can you not mount the ESC horizontally (vertically stacked with a spacer allowing airflow) a litte further back? The fuse is narrow, but quite high. This way is is difficult to get the battery in/out. Just a thought, Lucas Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 4, 2017 Share Posted December 4, 2017 Er, looks like Spaghetti Bol in there!! Glad I don't do much electfrics Quote Link to comment Share on other sites More sharing options...
Rob Ashley Posted December 4, 2017 Share Posted December 4, 2017 Coming along nicely there Tim. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 4, 2017 Author Share Posted December 4, 2017 I can actually get the esc’s under the servo’s which is neater and yes they can stack in front of the servos but I wanted to leave that space for pushing the motor cables back in after fitting the wing. One of the issues is the amount of plugs and cables to keep neat and clear of the servos themselves. Might put a balsa half former in front of the servos to prevent any inadvertent fouling. Battery comes out fairly easily with it as pictured as the esc’s simply lift over the side while you drop the battery in place. It might of course come down to getting the cg right as if I have to move the battery back from the nose the current packaging gets less attractive. Guess I’ll have a few more thoughts/trial fits yet. Tim Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 4, 2017 Author Share Posted December 4, 2017 Peter, Very true and while I used to like the smell of Castrol R and methanol it wasn’t half messy. Tim Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted December 4, 2017 Share Posted December 4, 2017 Sleek looking fuzz Tim. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 5, 2017 Author Share Posted December 5, 2017 And now the inside looks a lot neater. Lucas got me thinking about putting the ESC’s under the battery tray so I cut off the end of the tray resting on F3 and moved the support forward. This allowed acccess to slide them underneath which will have the added bonus of keeping them next to the cooling slots. Allows more room for the necessary plugs/cables above and generally feels closer to a neat solution. And the battery fits easily too. Leaving the space aft of F3 pretty clear. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 5, 2017 Author Share Posted December 5, 2017 More like a lasagne than a Spaghetti Bol Peter 🍽 Quote Link to comment Share on other sites More sharing options...
Lucas Hofman Posted December 5, 2017 Share Posted December 5, 2017 Nice! A more tidy solution is generally a more reliable solution either. Moving ESC's when you change batteries will lead sooner or later to solder joints breaking og connectors becoming slightly unplugged. Do not listen to Peter; he is just jealous on the clean silent models we are building compared to the rattling noisy smelly birds he has to deal with Regards, Lucas Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 5, 2017 Share Posted December 5, 2017 That looks good now. At least I have no problems fitting stuff in my new electric powered model, The Easter Eagle Senior. I can even fit a compact camera Quote Link to comment Share on other sites More sharing options...
Lucas Hofman Posted December 5, 2017 Share Posted December 5, 2017 Your new WHAT powered model Peter? Are you seeing the light? Who would have thought that? Cheers, Lucas Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 5, 2017 Author Share Posted December 5, 2017 Peter, Was it a 6 ft long fuselage I remember you posting? Must give you honoury membership of the LMA .✈️ Tim Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 5, 2017 Share Posted December 5, 2017 Lucas I have flown the odd electric powered model since the days of Speed 600s and Speed 400s. Had a few of them published. Easter eagle Mk1 and Mk 2 .Peyret Maubousin, Ohmsick Angel, Kitehawk These days as I get old (What do your mean "GET" I find that hauling a flight box up the long drag to the flying field is tiring so I do do more electric flying. Where I can just sling an old camera bag on my shoulder is more attractive. Not parting with engines and ic models though, Edited By Peter Miller on 05/12/2017 11:12:25 Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 5, 2017 Share Posted December 5, 2017 82" span, 18" chord, over 9 sq feet of area. Estimated weight under 5lbs and yes, 6 foot long fuselage http://www.modelflying.co.uk/forums/postings.asp?th=131952 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 5, 2017 Share Posted December 5, 2017 But Peter you know us old uns, we want pictures! Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 5, 2017 Share Posted December 5, 2017 Ah Peter, just reminded myself to ask you a question about the Grumpy. The Tigercat has the elevator a bit further forward than the Grumpy, what difference do you think it would make to its flying characteristics if I were to do the same to the position of the one on the Grumpy, bearing in mind that it already handles really well? This would be purely for a more scale like look and may not be worth the effort, planning on a 120% increase in size. Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted December 5, 2017 Share Posted December 5, 2017 Hi Ron You are not the only old un around here. If you want pictures just go to the build blog which is what the link is. Lots of pictures there. I will do it again. **LINK** Moving the tailplane forward should not make too much difference providing it is not a vast amount.. The CG at 25% makes for very stable model Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted December 5, 2017 Share Posted December 5, 2017 Thanks Peter. Quote Link to comment Share on other sites More sharing options...
Tim Ballinger Posted December 6, 2017 Author Share Posted December 6, 2017 Peter, Not built one of your wings before so just checking I have it right. 1. Wing tapers in thickness but is built flat to the board so all the taper is taken out top to bottom ie no packing re quired under spar tip. 2. Wing section is such that with rib sitting on the lower front spar (+ 1/16 sheet thickness) and rear cap strip ( also 1/16) that the effective 1/16 packing just allows the lower surface of the rib to just touch/clear the building board ? 3. I see from the original build log that the 1 “ dihedral marked on the plan is correct viz the 2” in the magazine article. Might just be my prints but all the ribs are @4 mm short . Not an issue of course but best checked before you cut out all the bits and get frustrated when you start to glue! Finally since I am taking landing loads through the wing I was thinking of changing the 1/4 sq top and bottom spars to spruce. Any thoughts? Tim Quote Link to comment Share on other sites More sharing options...
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