Big Bandit Posted May 20, 2011 Share Posted May 20, 2011 Hi BEB, Mine was a bit that way but not too extreme, as I made another due to "lumpy" soldering I adjusted it then. Cheers, Chris. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 20, 2011 Author Share Posted May 20, 2011 Well, I've unsoldered the undercart (which was a pain having to unwind the soldered bindings!). I put the trailing arm up against the drawing for bending the wire and its spot on. Then checked it in the side elevation of the fuselage and its about 1/2" too long! Chopped a bit off, rebent the ends and soldered it all up again - much better. Now the wheel are in a sensible place - it looked like it had "buck teeth" before! BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 24, 2011 Author Share Posted May 24, 2011 OK, the power train is installed. This is the first time I've "gone it alone" on an electric set up, previously I've always just bought the "recommended" set up. I've just invested in a wattmeter so this was "make or break" time! I was aiming for about 300W - and got 310W at full chat - not at all bad! I'm pleased with that. It drew 28Amps, and the ESC is rated for 40Amps continuous, so that should be fine as well. I'd better be careful, I just might be getting the hang of this electrickery stuff, and think what that would do to my "oily hand" image - I'd never be able to hold my head up in the bar of the "Flyin' Piston" again BEB Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 24, 2011 Share Posted May 24, 2011 BEB do you remember fixing a playing card to your pushbike frame so that the end was flicked by the wheel spokes to make a motorbike noise? I recon if you tape one to the nose of the BEBbit, that pokes out into the prop, then your reputation would stay intact Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted May 24, 2011 Share Posted May 24, 2011 Posted by Biggles' Elder Brother - Moderator on 24/05/2011 21:14:22: I'd better be careful, I just might be getting the hang of this electrickery stuff, and think what that would do to my "oily hand" image - I'd never be able to hold my head up in the bar of the "Flyin' Piston" again BEB Don't worry about it ,can get you in at the ,The switch mode arms.Congrats on you first independent choice of elec-tricery bits. Tom. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted May 24, 2011 Share Posted May 24, 2011 BEB, Your power train is reading roughly the same as mine so you should have more than enough power. Mine is showing 300 watts, pulling 30Amps steady on a 3s Lipo swinging a 10 x 5 prop. I remember my first 'guess' at an electric power train, only lasted a few flights, good old Watt meters, worth their weight in gold! Looking forward to some photos, nice 'top notch' build so far! Rich Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted May 25, 2011 Share Posted May 25, 2011 BEB, As it's quiet you can indulge in some urban guerrilla flying, sneak in under the radar a few aeros, back in the car and away before the victims wake up.. Chris. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 25, 2011 Author Share Posted May 25, 2011 But I haven't got an urban gorilla to fly Chris! Do you think that Webbies do them? BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 30, 2011 Author Share Posted May 30, 2011 OK just a quick update. I got some time in the workshop today so; rx fitted and everything except the ailerons tested and set up. All seems well. I've decided to fit her out with closed loop to the both the rudder and the elevator. I'll post some piccies on that when I get a chance to take some as some folks might be interested in how a full set closed loop is installed and set up. I've started the covering, covered the rudder, elevator and the wing so far, so just the fuselage tailplane/fin and ailerons to go. BEB Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted May 30, 2011 Share Posted May 30, 2011 Sounds like you're getting on well BEB. Will be great to see some pics. Closed loop on both sounds interesting. I think it's the best, lightest system, but only when set up properly. On small models I've used kevlar fishing thread which has worked well. Quote Link to comment Share on other sites More sharing options...
David Gilder Posted May 30, 2011 Share Posted May 30, 2011 Looking good BEB I managed to Maiden mine today at last and all went well.. Have just put in some down thrust on the motor tonight. I see quite a few people have had to do this so it might be something to bear in mind!! Hoping to get out for another few flights soon to re-trim but at least it has maidened now ready for Greenacres!!! Got a parcel from A.R. the other day with some banners, balloons, stickers and t-shirts!! What colour scheme are you going with then? I like the thought of close loop systems on the rudder and elevator!!! Will be interested to see that!! Keep it going... It will fly a dream!! Dave Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 31, 2011 Author Share Posted May 31, 2011 It better hadn't need downthrust Dave as the motor is not that accessable! If it does I'll have to change the wing incidence instead - much easier Chris. presumably you get the kevlar thread from fishing tackle shops? I've not tried that, I usually just use the standard stuff from Dubro or the like basically plastic sheathed steel wire. I too am a great fan of closed loop, correctly installed its very light and positive in action with no slop. Some folks say they find it a pain to install and set up - but to be honest I find its less work than a snake or push rod - maybe I'm just rubbish with snakes and pushrods! Often closed loop on evevator tends to use separate elevator halves - but I wasn't thinking and have joined my halves as per design - but it shouldn't make much difference it just means I have three wires exiting one side and only one on the other! As I say I'll try and take some photos, but the problem is the set up is very small and my camera is very rubbish - not good at making small detail visible. But I'll have a go. BEB PS Oh I forgot - Dave, the colour scheme is white with metallic red upper surfaces and black trim - its what I had "in stock" - but only just enough red I suspect, mustn't make any mistakes or I'll be redesigning the colour scheme! Edited By Biggles' Elder Brother - Moderator on 31/05/2011 11:06:22 Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted May 31, 2011 Author Share Posted May 31, 2011 Hi, as promised some attempts at pictures of the closed loop installation. This will be an "elevator in one piece" version so there will be two elevator connections on one side (top and bottom) and one rudder connection on each side (left and right). This means three outlets on on side and one on the another. A bit different, but it should be alright. For a model this size the exits need to be about 31/2" forward of the hinge points and more or less on a line between where the control horn will be and the servo horn. This means the upper elevator cable will have to pass through the top decking - which is only 1/16th balsa and so not really strong enough to support this. So, a small 1/8th thick balsa strip has been glued inside the fuselage at the exit points as a bit of local reinforcement. The holes were first drilled 1mm, and then opened out to an elongated shape in the direction of the cable run, at a very shallow angle to the fuselage side, using a miniture round file. The holes are now about 2mm diameter lying on a angle between the control horns and the servo horns. We then take 10mm length of small bore, approx 1mm, plastic tube and rough the outer surface up a bit to give it a key. This is then epoxied into each of the exit holes. These tubes will act as bearing surfaces for the cables runing through the exit holes. This picture shows the down-elevator and rudder cable exit holes, with the tube epoxied in place, on the port side.... Next we see the up-elevator cable exit on the rear top decking....(This one looks a bit long - I might trim it a bit!) Finally we can see the rudder cable-exit on the starboard side... I'm currently covering the fuselage. Once that is done I get back and deal with running the cables themselves and finally connecting everything up. BEB Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted June 1, 2011 Share Posted June 1, 2011 Posted by Biggles' Elder Brother - Moderator on 31/05/2011 11:03:41: Chris. presumably you get the kevlar thread from fishing tackle shops? I've not tried that, I usually just use the standard stuff from Dubro or the like basically plastic sheathed steel wire. As far as I can remember BEB, the thread was from ebay, came on a 25m roll I think so will last for some time. Sorry I can't be more specific. Yors is coming along nicely Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted June 8, 2011 Author Share Posted June 8, 2011 OK, I said I would detail how the full closed loop system is installed and adjusted. This is really by way of being for anyone who has not done a closed loop system and wants to see how it is done. I'm not claiming this is the only way - or even the best way - but it works for me First we fix the control horns on. One either side of the rudder and one top and bottom of one side of the elevator. As I said above its more common to have a split elevator with closed loop with elevator control horns top and bottom on both sides - but hey, this is WebBit, we do things different here So here are the control horns - need to trim those bolts! And another view... The rudder control horns are just a mite further back than I would like. really the holes should line up with the hinge line (as in any control system) but the stern of the fuselage is just a little too wide to permit full rudder movement if I do that. Its only a couple of millimetres so no problem. Closed loop is also very tolerant of this sort of thing because the wires can pivot really easily in the control horn holes and move sideways so they don't starin the hinges like say a control rod or a snake would do on a horn that was out of line with the hinge line. Next we thread the wire through the horn - here we are doing this on the rudder... (Sorry about the focus - or lack of it - I'm a rubbish photographer!) Prior to threading the wire through the horn a small ferrule is threaded onto the wire. The wire is then taken through the hole and back through the ferrule. Pull it snug and crimp the ferrule. We then thread the wire through the plastic tube bearings we epoxied into the fuselage prior to covering. This is shown in the photo below... Now for the servo end. You need special clevis fittings for closed loop. I use the Dubro ones but there are many available... A really blurred photo of the clevises. They have a short threaded rod inserted with a small hole for the wire in the free end. The threaded section provides us with adjustability. I always fit a nut to this threaded section as a locking mechanism. Now we pick up the wires that have been passed through the fuselage and attach them to the clevis rods. We get it about right before we crimp the wire at this end, and then fine adust with the thread... Here we are with everything connected. Adjust the wires with the control surfaces taped in the neutral position and tighten the wires just until the slack is eliminated. They do not have to be really tight - just not slack. So here's the finished job, Top view... Bottom view.... And side view... Just have to trim the loose ends of the wire pulled through the crimps and also the bolts and its all done. There is absolutely no slop in the system and its working fine. I did try to take a video - but failed, I'll have another go! Anyway, there you go. Closed loop in a nutshell. I my view the simplest, easiest and lightest control system. And second only to short control rods with ball links for precission. BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted June 11, 2011 Author Share Posted June 11, 2011 OK the BebBit is finished! At the beginning I said that this was going to be a "stick one piece of wood a day" sort of biuld. And boy was I right! Building the BebBit has coincided with one of the busiest periods at work I've known! I don't think any building session lasted more than 30mins and most were much shorter! So it does show that even if you're 'time poor' you can biuld! I don't normally have such a problem getting building time - but this one has been very much "snatched" time here and there. The light was going but at least its in focus - unusual for me! A younger female BEB modelling the BebBit! So, just have to set the control throws, all the directions have been checked, and check out the CoG and we're ready for a maiden. Let's hope the weather is a bit better tomorrow! BEB Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted June 11, 2011 Share Posted June 11, 2011 Looks great BEB. Good luck with the maiden. Quote Link to comment Share on other sites More sharing options...
David Gilder Posted June 11, 2011 Share Posted June 11, 2011 Great one BEB Lookng forward to seeing it in person... Not long now!!!! Dave Quote Link to comment Share on other sites More sharing options...
Ian Jones Posted June 11, 2011 Share Posted June 11, 2011 Just seen the photos in the completed webbits thread too - looks great, good luck with the maiden (and the weather!). Ian Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted June 11, 2011 Author Share Posted June 11, 2011 Thanks Guys! BEB Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted June 12, 2011 Share Posted June 12, 2011 Looks great BEB Quote Link to comment Share on other sites More sharing options...
Big Bandit Posted June 12, 2011 Share Posted June 12, 2011 Looks brilliant BEB like the use of the sticker and trim lines.Chris. Quote Link to comment Share on other sites More sharing options...
Richard Harris Posted June 12, 2011 Share Posted June 12, 2011 That's nice BEB! Good luck with the maiden, just hope this weather improves for you Rich Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted June 12, 2011 Author Share Posted June 12, 2011 Yep, you're right Richard, no chance today - its pouring down and quite blustery! I'm having a pottering round the workshop tidying up and getting ready to start the Extreme Flight Extra sort of day. Hoping I get a bit more concentrated building time on that one - at least its only ARTF so shouldn't take too long. Chris - yes the sticker was a freebee from Webbies and the trim tape just seemed a quick and easy way to "set it off". I was originally going to add some matching white strips on the red upper surfaces - but I think it would look too fussy so I probably wont bother. BEB Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted June 14, 2011 Author Share Posted June 14, 2011 OK, I've taken advantage of what might be the only good day this week - and the BebBit has flown. Fairly uneventful maiden, except quite a lot of downtrim was required. Put a bit of packing under the trailing edge for the second flight and that was a lot better. Plenty of power. Good aileron authority. Inverted needed a tad too much "down" elevator even with the packing in and the glide was rather too nose down, so she might be a tad nose heavy - which is no bad thing as it needed a fair bit of lead to get it too balance on the spar. Might remove a little and see how it is then. BEB Quote Link to comment Share on other sites More sharing options...
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