Adrian Smith 1 Posted May 31, 2020 Author Share Posted May 31, 2020 Time to look at the elevator damage. Not too bad. The only sticky issue for me will be straightening the trailing edge before the repair as I am not looking to rebuild the whole elevator. Not yet anyway. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted May 31, 2020 Author Share Posted May 31, 2020 I am going to change the original horns for others in stock which use a split pin rather than the original screw and nut which were a pain on two counts. The screw head was easily burred making them difficult to unscrew and the nut the other side of the horn over time degraded the plastic. Old ones .... Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted May 31, 2020 Author Share Posted May 31, 2020 I removed all the covering and decided to cut and drill out the Robart hinges with my Dremel. The process went better than I thought although I need to replace some drill bits afterwards. Next job will be to first repair the elevator which is easier said than done I am sure, then cover the elevator and re-glue the hinges. I will have to order some more cable as I need 2 metres of continuous wire per elevator as I going to rewire the how set up. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 1, 2020 Author Share Posted June 1, 2020 In between flying I managed to re-assemble and temporarily glue the elevator. I used thin cyano initially. Two things. As can be seen there is a bit of a kink still in the trailing edge. I would imagine wetting and weighting with heavy weights on a flat surface may put that right. Assuming i can do a passable job I will finish off with balsa strengthening fillets in three or four places. Edited By Adrian Smith 1 on 01/06/2020 16:53:17 Quote Link to comment Share on other sites More sharing options...
extra slim Posted June 1, 2020 Share Posted June 1, 2020 wow, even after that, I would be tempted to drill a hole and put a carbon rod/arrow shaft running all the way through the middle of the ribs, as behind the hinge line will be impaired by the hinges... Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 1, 2020 Author Share Posted June 1, 2020 extra slim, that sounds like a good idea. I have a variety of sized carbon rods laying around in the workshop. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 3, 2020 Author Share Posted June 3, 2020 After a bit of wet and heat treatment the trailing edge looks much better. Not perfect, but close enough for hack. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 3, 2020 Author Share Posted June 3, 2020 Now for the reinforcing job. I had a look at my carbon fibre rod stock and I really didn't have any of a suitable diameter - either too thick or two thin. Back to the drawing board. In the end I decided to try and use balsa fillets and lite ply fillets strategically positioned to provide the strength. For the trailing edge I used 1/16" light ply fillets that attach to the rib and trailing edge and epoxyed in. For the leading edge there was room for two balsa fillets with a gap in between large enough to fit the Robart hinges. In hindsight I think I should add another couple of hard balsa fillets on the outboard section of the elevator. Hopefully all the work will not add any significant weight to the elevator. Edited By Adrian Smith 1 on 03/06/2020 16:15:21 Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 4, 2020 Author Share Posted June 4, 2020 Last fillet glued into place using some 1/4" balsa . Not pretty, but effective. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 4, 2020 Author Share Posted June 4, 2020 I decided as I had to remove the damaged elevator I am going to change the wire connection at the servo end from this - To this - The reason being that I am at least able to adjust the couplers from both ends of the wires. This will make life easy when setting up the elevators' travel. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 4, 2020 Author Share Posted June 4, 2020 At a matter of interest I had a look at the trailing edge on the starboard elevator while it's still in situ. It is probably difficult to see in the photo but there is a tiny dip in the edge around the middle of the elevator. I don't feel so bad about my efforts to straighten up the port elevator during the repair. I hadn't quite got enough white covering so I decided to cover the elevator in an almost matching blue and add some pattern to it later on in the job. Heat gun next on it and then I am ready to attach to the tailplane. Robart hinges installed and Gorilla glued, not forgetting that the inboard hinge needs shortening on the tailplane end due to the carbon rod going through the wing. All taped and set aside to dry. Edited By Adrian Smith 1 on 04/06/2020 16:20:48 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted June 4, 2020 Share Posted June 4, 2020 Nice repair work Adrian. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 4, 2020 Author Share Posted June 4, 2020 Cheers, Ron. For bit of fun I looked on youtube for any Capiche 140 clips and interested to find this one where, at the end, the guy ended up in the grass on landing and the starboard elevator breaks off in almost the same place as mine! I must admit I was surprised he made such a hash of what looked like a straightforward landing. enjoy ...... Oops! Landing mess up Edited By Adrian Smith 1 on 04/06/2020 19:26:45 Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted June 4, 2020 Share Posted June 4, 2020 Good job Adrian. Hope your next flight goes off without a hitch. I must say that the Capiche was one of the easiest aircraft to land on the spot provided you kept the approach speed slow. The chap in the video is obviously still learning how to fly the Capiche but nevertheless the last landing was very poor. The manual does warn against running into long grass with the stick held back as there is a real danger of ripping off the elevator end. It is surprising how many pilots just forget to overshoot when their landing starts to go wrong! Had he overshot from the first bounce he would have been fine. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted June 5, 2020 Share Posted June 5, 2020 Hello Adrian, fantastic work on the refurb, Many years ago I was at the flying field when a capiche went in. Horrific damage, the owner took the decision to repair the model and did an ace job of it. He wrote a piece for the club website. click here. hope you enjoy it, hopefully compliments your thread nicely. craig Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 5, 2020 Author Share Posted June 5, 2020 Thanks, Craig. The link to the article is fantastic and while the damage was a lot, lot worse than mine it shows what can be done. Appreciate you sharing it with the forum. It just goes to show NEVER be afraid to try and repair and damaged aircraft least of all an ARTF where you have to start from scratch. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 6, 2020 Author Share Posted June 6, 2020 Home stretch approaching now. Added the different control horns by threading the studding through the elevators. I taped the rudder cables to the fuselage top out of the way so I can work freely. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 6, 2020 Author Share Posted June 6, 2020 Next onto threading the elevator wires loosely. Nice and tidy through the fuz. Then fired up the RX and TX to do the final adjustment and fitting the split pins last.. The cables are much more taut and the adjustment was easier than with the original fittings. I taped up the elevator gaps too. All that remains is to add some trim film to the repaired elevator to make it blend in better with the undamaged elevator. Hopefully I will go through maiden No2 in the next week or two all being well. Edited By Adrian Smith 1 on 06/06/2020 16:02:51 Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted June 6, 2020 Share Posted June 6, 2020 Good job Adrian. Good luck with the first flight after repair. Be interesting to hear if the electric setup gives you unlimited vertical. It ought to with weight at less than 5 Kg all up. If it doesn't, try a 20x13 APC - that ought to be within the motor's capability but do check the amp draw. Remember, in the air the max amp draw will reduce by around 15%. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 20, 2020 Author Share Posted June 20, 2020 Well went to the field today to do another test flight. All was well until i did some fastish rolls after 2 minutes. The plane started to behave as though badly out of trim and became very difficult to control. My first reaction was a CoG issue. How I got her down undamaged I don't know ... but managed it. A quick look showed the elevators were fine as was the rudder. However, the starboard aileron was badly out of line with wing and the other aileron with the stick centred. The servo arm looked to be misaligned. Anyway put that right and tried again. Same thing and another stressful landing. Same issue with the servo arm. I am now wondering if the arm is not quite tight enough on the spline and any high alpha move is enough to displace the arm on the spline. Oh well at least she lives to fight another day. I will change both aileron servo arms from plastic to metal when I am next in the work shop and then see what happens. The servos are Hitec usually pretty reliable. I am almost certain it's not the TX trim playing up as all my other aircraft in the memory are fine. I will study both video clips I took at the time to see how things developed, but I am not sure I will learn much. Watch this space ....... Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted June 20, 2020 Share Posted June 20, 2020 Adrian, I had exactly the same problem and it was servo arms moving on the splines, funnily enough the servos were also Hitec. I 3D printed some new ones and they are a much better fit. Quote Link to comment Share on other sites More sharing options...
Adrian Smith 1 Posted June 20, 2020 Author Share Posted June 20, 2020 Thanks for your thoughts, Ron. I think you have certainly confirmed my initial feelings. Back to workshop on a rainy day then ......Ho Hum. Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted June 20, 2020 Share Posted June 20, 2020 Well done Adrian. Good recoveries. I was going to ask if you might have got a non Hitec servo arm by error but Ron seems to have had the same problem. I've never known servo arms of the same make as the servo not working perfectly. Very odd! Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted June 20, 2020 Share Posted June 20, 2020 @Peter - I think that in my case the servo arms were not OEM ones so the fit was not that good. Too be fair, I haven't had any problems with any of my other Hitec servos. Quote Link to comment Share on other sites More sharing options...
Peter Jenkins Posted June 20, 2020 Share Posted June 20, 2020 Ah, that would explain your problems Ron. Adrian, are you using genuine Hitec servo arms in that case? Bottom line is not to use a servo arm unless you are sure the spines are exactly the same design as the servos. It is very easy to find one that fits but which will slip when under strain. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.