Phill @ Elite Workwear UK Posted October 2, 2012 Share Posted October 2, 2012 Hi, just thought I would ask the question. I am currently building a ARTF Velox Revolution 2 from Pro-build. I have flown but never built a large model (2m span for 50cc petrol engine) like this and I have come to the part where I connect the push rods. The instructions suggest 3mm push rods with ball joints at the servo end and clevises (the type with a screw through) at the horn end. I have got some push rods that need cutting down but only 1 end is threaded. Would epoxying the ball link ends on be strong enough or should I get some threaded rod and screw both ends on? Any thoughts would be much appreciated Phill Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 2, 2012 Share Posted October 2, 2012 For a model of that size and weight, my personal preference would be to avoid using glue of any type for the push rods. Threaded rods all the way! Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 2, 2012 Author Share Posted October 2, 2012 Hi Allan, Thanks - that was my gut feeling but I was just wanting to avoid another trip to the LMS if it wasnt needed. I will get some rod and away we go! Cheers. Quote Link to comment Share on other sites More sharing options...
Alan Cantwell Posted October 2, 2012 Share Posted October 2, 2012 its very important that you have a good stiff link from the elevators to the servo, can you not put the servos at the back end, and use short 3mm rod? rudder should always be closed loop, tailwheel fixed, or linked to the inner holes of the rudder servo, going to 2 stiff springs on the tailwheel to act as a servo saver, the rudder takes the most hammer, and a good, powerfull servo should be used, peferably 2 linked to each other, we flew 40% aerobatic models with DA150s in, the longest link to a servo was on the ailerons, and these where only 3inch, ball links where rocket city, 3mm links where kavan, and kavan only, i dont like pushrods in a powefull aerobatic model simply because a substantial one, becomes a heavy one, and during violent manouveres, this weight multiplies, i hope this helps, we flew quite a lot of powerfull models ike this, there are several tricks to get good results, Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 2, 2012 Author Share Posted October 2, 2012 Hi Alan, the links will be 3mm and only around 4 inches on the elevators, 1 x 9kg servo on each half, the rudder is closed loop with a 11kg servo and the same on each aileron. The aileron linkages are slightly longer, maybe 6 inches but again 3mm wire. The prob was with the rods I bought were only threaded ar 1 end. I think it will be best if I get 3mm threaded rod then I can make them and still have some adjustment. I have flown one of these before and it was nice and smooth and made my flying look better than it really is. Thats why I wanted one.haha. Quote Link to comment Share on other sites More sharing options...
crispin church Posted October 2, 2012 Share Posted October 2, 2012 get your selve a tap and die set make your own threads dont forget to put lock nuts on Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 2, 2012 Author Share Posted October 2, 2012 Hi Crispin,That sounds like engineering to me. I struggle to hold a screw driver properly. Actually, my dad said about that and I did have a quick google about so may just order some. Thanks for your help. I will be using locking nuts with thread lock. Quote Link to comment Share on other sites More sharing options...
Alan Cantwell Posted October 2, 2012 Share Posted October 2, 2012 problem with using 3mm rolled thread rods, is you are actually usening 2.5mm rods, for that is the core diameter of the rod, i prefer to screw the ends of steel rod, therefore leaving the middle bits solid, believe me, its easy enough, but if you want them made for you, drop me a PM, Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 3, 2012 Author Share Posted October 3, 2012 Hi Alan, Thanks for the offer and I see what you mean. I will pop and see the local precision engineering firm and see if I can borrow their tap + die set and have a go at making them up - they are almost next door at work. Knowing my practical skills though I may just have to take you up on that offer Alan. I wont be able to get into the workshop for the next day or 2 tho due to the kids (in truth I have done well to do 2 evening running) Thanks All! P Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted October 3, 2012 Share Posted October 3, 2012 Pete Tindall offers some very nice linkage sets here Phil......might do the job for you... Not cheap but then a failed linkage will probably cost you the model..... Edited By Steve Hargreaves - Moderator on 03/10/2012 12:43:34 Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 3, 2012 Author Share Posted October 3, 2012 Hi Steve - thanks for that - I will have a closer look. I have some carbon rod and ends left from a repair of a heli I did a while ago, might see if I can conjour something up. Quote Link to comment Share on other sites More sharing options...
Alan Cantwell Posted October 3, 2012 Share Posted October 3, 2012 please dont conjur something up, do it properly, Quote Link to comment Share on other sites More sharing options...
Allan Bowker Posted October 5, 2012 Share Posted October 5, 2012 Alan Why do you say that the rudder should always be closed loop? Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted October 6, 2012 Share Posted October 6, 2012 Hi Phill, Ive just recently installed the aileron control linkages on a model im building and like Allan, I would recommend cutting threaded studding/rod to your particular length. In addition I have replaced the standard servo output arm with replacement commercially availiable "Ball Link Servo Arms", availiable for most servo makes, such as these. I use threaded rod and then sleeved the rod with carbon tube to stiffen it further (and looks nicer than exposed threaded rod IMHO). At the control horn end I use two carbon control horns with a ball joint to help reduce any twisting action on the horn. Heres my installation with the threaded rod sleeved. I used nylock nuts Craig Edited By Craig Carr on 06/10/2012 09:16:59 Quote Link to comment Share on other sites More sharing options...
Phill @ Elite Workwear UK Posted October 6, 2012 Author Share Posted October 6, 2012 Hi Craig. They look like spot on bits of kit. I will have a google around for them. I have organised a tap n die set to have a play with. I like the idea of sleeving in carbon tube to make i look better. Cheers all that advised on this. Quote Link to comment Share on other sites More sharing options...
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