Spikey Posted July 2, 2016 Share Posted July 2, 2016 I'm now using a standard snake for the very first time and because it got here in a Jiffy bag, it wants to stay bent. Is there a magic way to straighten it? Quote Link to comment Share on other sites More sharing options...
cymaz Posted July 2, 2016 Share Posted July 2, 2016 Bit of heat and bend it the opposite way Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted July 2, 2016 Share Posted July 2, 2016 Try borrowing your daughter's recorder, sit cross legged in front of it and play a mystical tune - it should uncoil readily, but wear CE approved safety glasses in case it spits venom at your eyes... Quote Link to comment Share on other sites More sharing options...
Stevo Posted July 2, 2016 Share Posted July 2, 2016 I would assume a bowl of hot water and bend the other way. But I've never had to do that as if the snake is supported well along its length it will straighten anyway... Hello Cymaz, my old sparring partner BTW Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted July 2, 2016 Share Posted July 2, 2016 yeap - with Stevo here. Why do you specially need to straighten it? Is it very tightly coiled? In which case I'd send it back as not fit for purpose. If its just got a bit of predilection to curve one way then I'd leave it as It will adopted the path you support it along in the model and that will be that! BEB Quote Link to comment Share on other sites More sharing options...
Stevo Posted July 2, 2016 Share Posted July 2, 2016 My golden rule of snakes is that they must be supported so that they don't move. Anywhere, at all... anywhere. It mostly happens when the core is under compression and the snake will bulge out in the middle. I support mine at every bulkhead.. or more... Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted July 2, 2016 Share Posted July 2, 2016 Hang it up by one end and gravity/plastic's memory should sort it out, a bit of GENTLE heat will speed the process up. Quote Link to comment Share on other sites More sharing options...
cymaz Posted July 2, 2016 Share Posted July 2, 2016 Posted by Stevo on 02/07/2016 13:55:44: Hello Cymaz, my old sparring partner BTW Good Day! Flying at Woodsprings Sunday and at Greenacres next week....see, I do leave the parish now and again ! Edited By cymaz on 02/07/2016 14:46:41 Quote Link to comment Share on other sites More sharing options...
Spikey Posted July 2, 2016 Author Share Posted July 2, 2016 Cheers chaps. Gentle heat it is Quote Link to comment Share on other sites More sharing options...
PatMc Posted July 2, 2016 Share Posted July 2, 2016 Dip it in very hot water then pull the ends until it cools - should only take a minute or so. Apart from the two ends, snakes don't need to be supported anywhere along their length. It's only the two extreme fixing points that have any affect on the translation of servo movement to control surface movement. If the sight of them flopping about appears untidy a little loose guidance here & there should suffice. Quote Link to comment Share on other sites More sharing options...
Former Member Posted July 3, 2016 Share Posted July 3, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Stevo Posted July 3, 2016 Share Posted July 3, 2016 All of a sudden swmbo is interested in this thread. Quote Link to comment Share on other sites More sharing options...
bouncebounce crunch Posted July 3, 2016 Share Posted July 3, 2016 Posted by Stevo on 03/07/2016 08:53:04: All of a sudden swmbo is interested in this thread. Snake too bent is it ????????? Quote Link to comment Share on other sites More sharing options...
Former Member Posted July 3, 2016 Share Posted July 3, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Shaunie Posted July 3, 2016 Share Posted July 3, 2016 Coil up tightly, place in a hot open fire, observe closely until completely melted, fit a closed loop system, only have to trim the aircraft the once 😎. As you may imagine I don't like snakes as I find every time you fly the trim changes. However it's a plus one for sliding the outer down a close fitting piano wire and warming it up. The only snakes I use now is a piano wire up a snake outer or the snakes with a piano wire up the inner. I also agree that the outer should be fully supported or it will "belly out" under compression. Shaunie. Edited By Shaunie on 03/07/2016 22:40:49 Quote Link to comment Share on other sites More sharing options...
Stevo Posted July 3, 2016 Share Posted July 3, 2016 Couldnt agree more. Those snakes in my picture are for closed loop routing. Quote Link to comment Share on other sites More sharing options...
PatMc Posted July 3, 2016 Share Posted July 3, 2016 Posted by Shaunie on 03/07/2016 22:39:14: I also agree that the outer should be fully supported or it will "belly out" under compression. Shaunie. Edited By Shaunie on 03/07/2016 22:40:49 How can it ? If the outer is secured at both ends that's all that matters. Quote Link to comment Share on other sites More sharing options...
Craig Carr Posted July 4, 2016 Share Posted July 4, 2016 Posted by PatMc on 03/07/2016 23:05:24: Posted by Shaunie on 03/07/2016 22:39:14: I also agree that the outer should be fully supported or it will "belly out" under compression. Shaunie. Edited By Shaunie on 03/07/2016 22:40:49 How can it ? If the outer is secured at both ends that's all that matters. They cant. like pat says only each end needs securing (ie the snake outer can't physically grow) I must admit though I do still pass them through holes drilled in formers but in reality this is nothing more than cosmetic Quote Link to comment Share on other sites More sharing options...
Stevo Posted July 4, 2016 Share Posted July 4, 2016 Lots of things at play here, not withstanding the length of the snake, snake material and what the inner is. Given that it should be securely attached at both ends of course. If it runs round a curve, under tension it will try and flatten and of course the reverse. When I put a snake in my Be2c to control the tailskid (yes I know.. a bit cosmetic!) I attached it at each end securely. I could hold the skid still and get the servo to move indicating play and watched the snake move around (Obviously not to detrimental on a tailskid). Supporting it at 3 places along its length cured that. For shorter runs and almost no stress (throttle) I support at both ends only. Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted July 4, 2016 Share Posted July 4, 2016 The support at both ends theory is absolutely correct with no significant clearance between the tube and snake inner - but the more clearance the more difference there is between tension and compression...think of a snake with a large diameter section of outer to visualise the effect in an extreme case! I suspect that the better quality snakes such as Sullivan with ridged inners are designed to work with smaller clearances? Quote Link to comment Share on other sites More sharing options...
Shaunie Posted July 4, 2016 Share Posted July 4, 2016 Make a push-pull linkage with say a brass tube outer and support at each end is acceptable. But a snake is by definition flexible and under a push loading the outer will try to bend if it is anything other than absolutely straight. Put another way, if the snake is curved between supporting points when the inner is under compression it will try to belly out, pushes against the inside of the outer which, as it is flexible also stretches outwards, end result is lost movement and excessive friction. Ideally all control runs should be absolutely straight whatever type they are. Shaunie. Quote Link to comment Share on other sites More sharing options...
PatMc Posted July 4, 2016 Share Posted July 4, 2016 Shaunie, the clearance between inner and outer is exactly the same whatever route the snake takes & it's that clearance that causes the lost movement. It matters not a jot whether or not the snake is supported, the inner will always try to move sideway within the confines of the outer when under compression. When installing keeping it as straight as possible between the two end fixing points will keep friction & scope for movement to a minimum simply because it's the shortest route but any extra support is no more than cosmetic. Quote Link to comment Share on other sites More sharing options...
KiwiKid Posted July 5, 2016 Share Posted July 5, 2016 Snakes - how to un-bend? LOL - when I saw the title of this thread, I expected it to be from the slope forum. Quote Link to comment Share on other sites More sharing options...
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