Andy Nash Posted April 27, 2011 Share Posted April 27, 2011 Hi Rich That's a good photo Rich. Shows how you have setup the servos clearly. I see your using the 1/8 welding rod for the servo rods, very good. What's type are the MG servos your using? Also is the glass-fibre plate for the head the 1.5mm sheet we normally use? Any idea what the blade weight is and have you added tip weight? Sorry mate to ask lost of questions, I 'm interested! Regards Andy Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted April 27, 2011 Author Share Posted April 27, 2011 Bill, Isn't it great watching 'proper' football Andy, Yes 1/8" welding wire machined down on the ends a touch and then M3 threads cut. The flexible plate is made from 1mm thick Fibre Glass sheet so is a little thinner than the norm, mainly because it is a smaller model . Because of this I used really hard balsa for the trailing edge to up the weight of the blades, but I haven't weighed them as it was a guesstamut! I was thinking that the plate is quite thin keep the weight and size of the blades a touch bigger to get a flatter rotor disc. The servos used are the Hitec 225 MG's I have now added my spats as the grass has been cut at the field, spinner is also added as it was a bit 'bare'. Had another 5 flights this evening to try and get a few flying shots, must have taken 50 photos and only a few were any good. Rich Edited By Richard Harris on 27/04/2011 22:14:52 Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted April 28, 2011 Share Posted April 28, 2011 Rich, That's brilliant, so informative. I think I would have spent hours trying to work out how to do it properly. I did notice that you used some sort of mounting / gear box to take the main shaft for the rotor, what was that. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted April 28, 2011 Author Share Posted April 28, 2011 Chris, Yes its a Master Airscrew 500 gearbox , they are pretty hard to come by now but work well on these smaller autogyros. I have also tried an old brushless motor and removed the armature windings which just press off. They are pretty cheap these days so a new one could always be butchered, you could even mount the head on the prop driver?But it would be wise to add a bit of loctite on to the shaft! Autogyros don't glide too well when a rotor comes detached (don't ask me how I know!). For something this size you would need at least a 4mm diameter shaft. Rich Edited By Richard Harris on 28/04/2011 14:12:40 Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted April 28, 2011 Share Posted April 28, 2011 Chris I have used these gear boxes before and are great,maybe you can find them over there but taking a hammer to an old brush less motor is the fastest way right RICH Gear Boxes : AstroFlight, Welcome to the AstroFlight online Store BILL Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted April 28, 2011 Author Share Posted April 28, 2011 Well, I seem to have made a miss calculation with my wing rib template..didn't notice until I came to butt up the 2 outer wing panels with the centre section. Should be an easy fix. I took a few photos of what I have done with a little brushless motor when utilising it for a spindle. Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted April 29, 2011 Share Posted April 29, 2011 Rich, Bill, thanks for that I would never have thought of it, I can feel a project coming on now. Cheers, Chris.Edited By Big Bandit on 29/04/2011 09:23:51 Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted April 29, 2011 Author Share Posted April 29, 2011 Thanks for the day off Wills and Kate..sorry I didn't get chance to watch the TV..just managed to switch it on in time for the Battle of Britain fly past Stub wing is almost completed apart for a touch of rubbing down and a few pieces of wood here and there. I have made 2 slots at the tips, this will be for the mast posts to slot into. I bet it would fly like this! I have chopped about 14" of the original wing Rich Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted April 29, 2011 Share Posted April 29, 2011 Boy I bet where you mount the masts is going to be the key to this one. Are you going to set the unit with a battery loaded up in her on a couple of balancing rods to find the C of G and mark the wing tips accordingly? Sorry just me think out loud again I got to stop that. I LIKE IT !! Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted April 30, 2011 Author Share Posted April 30, 2011 Bill, I have mounted the spindles axles on the CG, whether this is the correct place I have no idea? I have made a start on the hubs, drew and printed some triangles out and stuck them to a piece of fibre glass sheet and cut them as a pair. Thickened up top and bottom with 2 discs of 4mm birch ply. Through the centre of these will run a brass tube as a bearing. Have also made a start on the blades, these are in the process of drying as they are made from 2 laminations of 3mm balsa, I will add a hardwood leading edge before sanding them to a lifting clarke y aerofoil. I will take a few photos of these tomorrow if I get chance to work on them some more. Rich Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted May 1, 2011 Share Posted May 1, 2011 Very professional Looking Rich. Quote Link to comment Share on other sites More sharing options...
Rob Lewis Posted May 1, 2011 Share Posted May 1, 2011 This thread shows whats possible with some imagination, knowledge and building skills. Great work Rich, looking forward to seeing the 3rd version take to the skys. Rob Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted May 1, 2011 Share Posted May 1, 2011 Great work Rich, looking forward to seeing it fly. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 1, 2011 Author Share Posted May 1, 2011 Thanks guys, Just wish more people would have a go at these things, if it spurs one person on to 'have a play' then that is great in my eyes. Ok, To keep with the Twist' theme I decided to have a go at making some curved blades for the last version. Not the easiest thing in world to get a uniform aerofoil around a curve. These are made up of 2 pieces of 3mm balsa with a 6mm square Ramin leading edge, epoxy used through out.. You can see from the photo that I added reference marks to aid me in getting the aerofoil some where right. Must remember to make 3 LH and 3 RH!!! I will add shim strips to the GF triangular plate to give me the required negative incidence to get them spinning in the correct direction. More later once I have completed the blades. Have to wait for the washing to dry.....she wasn't impressed by the balsa dust! Rich Quote Link to comment Share on other sites More sharing options...
Steven Webb (Steve Webb Models) Posted May 2, 2011 Share Posted May 2, 2011 Hi Rich, I've been getting the thread updates sent to my phone ( tech boy or what? or 'what' the Mrs Jen says). Anyhow I didnt post from the phone as I couldnt see the pics. The twisted rotors? rotors with a twist? Very interesting Rich. I think you are correct in the spindles being on the C of G - I am casting my memory way back to a DB Auto Gyro with a similar configuration ( 25 years ago? plus!) and my mate balanced the gyro on the spindles. I can remember him saying the balance point is easy to find its on the masts ( spindles). Unless anyone knows different! I think your correct. The Twist blades? I hope they work? but wont they cause the C of G to vary slightly? Is there a C of G rotorblade variation expert on the forum? If the blades rotate, but pat of them is behind or ahead of the C of G will that not cause the c of g to be variable? I'm thinking as I type...just thoughts. Maybe I'm thinking of too much complication and if it works it works! The Twin Rotor WebBit wing, that looks nice and compact doesnt it! My flabber is aghast ( I am flabber ghasted) at the video of the WebBit in the strong winds. We were out flying a Boomerang Intro yesterday and that got knocked about in the breeze. On the last landing some bad gusts and a beeper saying 1 minute of fuel left resulted in a slight overshoot into the long grass and front U/C breakage. it'll repair, but to think that model was having problems with the gusts! I was quite shocked to see the Twist handle the breeze so well. I love the out take vidoe too! Glad the damage wasnt to bad. Regards to all! Steve Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 2, 2011 Author Share Posted May 2, 2011 Sometimes we only put the best bits onto video, here are the 'bad bits'! It was very windy yesterday and I did manage quite a few flights, but it was the gusts that was the problem. In the second clip you can see the Twist bouncing on its UC I didn't get the last flight (famous last words 'just one more') but the wind caught me out resulting in a tip over and the tailplane being broken off from the joint. Repair work in progress. Rich Edited By Richard Harris on 02/05/2011 14:39:17 Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 2, 2011 Author Share Posted May 2, 2011 Steve, You stopped me in my tracks regarding the CG position on the curved blades! something I really didn't think about. So I have been cautious and moved the mount position further back of the CG to give each blade a nose down attitude when balanced on this point. Everything is basically completed, just one final rub down a slap some covering on. Re glued the tailplane back on also I'm nearly all built out! Rich Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted May 2, 2011 Share Posted May 2, 2011 Rich: Just like you to build till you drop. We all want to see your creation fly but take a brake BUDDY stand back take a breath and look everything over one last time. I have a real good feeling about this one, It looks right and proper. Regards Bill Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted May 2, 2011 Share Posted May 2, 2011 Rich, I don't know where you get the energy, may be it's an age thing . Can't wait to see the twin rotor fly, but I think I'll try the single rotor first. As a thought, where did you get the belt sander from, I'm just rebuilding the garage into a workshop and want to get it stocked out properly from the word go, currently I'm in a 6 x 8 shed full of models and kit. The garage is 16 x 8 and when the bikes gone I'll have loads of room to build seriously. Interested in a modelers lathe as well. Cheers, Chris.Edited By Big Bandit on 02/05/2011 21:05:22 Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 2, 2011 Author Share Posted May 2, 2011 Chris, I bought mine off the chippie at work, it wasnt 'man' enough for what he wanted. Best tool in my workshop/garage, use it a lot. Try here http://www.screwfix.com/p/titan-d15-b10-a-belt-disc-sander-230v/52590 The new garage workshop sounds good, make sure its well insulated. Mine gets cold during the winter. Rich Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted May 3, 2011 Share Posted May 3, 2011 Hi Rich, Cheap as chips, the in built disk sander will come in very handy. the one I use at the moment is 10" and over 30 years old, was home built, but has been very useful over the years. Time for a change me thinks. Yes I'm fitting a pitched roof with 50mm Cellotex between the trusses. box section steel powder coated roof. Lining the walls with 18mm moisture resistant t&g chipboard 4' x 2' panels on timbers with foil backed fibre glass infill, and interlocking rubber flooring. Replacing the infill panels on the main wooden doors with 15mm t&g boards insulated on the inside with a stable style personal door. The missus wants the old shed which is a summer house style for a planting shed. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 7, 2011 Author Share Posted May 7, 2011 Almost at the finishing post! Just need to cover my masts. I will post some photos later when its all completed. Looks like flying is not an option today or tomorrow as its thundering here. I was going to go to Old Warden but I think I will give that a miss. Looking on the bright side its doing my new lawn the world of good! Must be at least 6 weeks since it rained? Rich Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 7, 2011 Author Share Posted May 7, 2011 Well that's my build just about wrapped up, need to go and get some collets to fit to the shafts from my LMS and I'm ready to try this thing out. Weather does look as though it wants to comply so I will just have to weight. For some reason I have got a warp on my left wing, not sure how to get it out as its all sheeted? A few photos, i will let you know how it goes. Rich Quote Link to comment Share on other sites More sharing options...
BILL PETTIT Posted May 7, 2011 Share Posted May 7, 2011 THAT IS ONE BEAUTIFUL BIRD !!!!! If it flies likes she looks hold on to your radio! Best of luck and I hope the weather clears for a late video. Regards Bill Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted May 7, 2011 Share Posted May 7, 2011 looks supperb Rich Quote Link to comment Share on other sites More sharing options...
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