Christopher Morris 2 Posted March 3, 2020 Share Posted March 3, 2020 Hi, Where can i buy 2mm pushrods 750mm long. I picked up an old Boomerang 40 That has 2 pushrods missing to the tail & found loads up to 500mm but not longer. These rod go through what i assume is 2.2mm piping. to give some extra rigidity.to the rods. Thanks Quote Link to comment Share on other sites More sharing options...
Robin Colbourne Posted March 3, 2020 Share Posted March 3, 2020 SLEC Snakes or 2mm carbon fibre rod Quote Link to comment Share on other sites More sharing options...
paul d Posted March 3, 2020 Share Posted March 3, 2020 2mm piano wire with soldered on threaded extenders? Quote Link to comment Share on other sites More sharing options...
Martian Posted March 3, 2020 Share Posted March 3, 2020 What colour is the internal tube, without a picture not easy to say but at a guess it uses a snake with metal fitting on the end as indicated look at SLEC and see if you can match Quote Link to comment Share on other sites More sharing options...
Christopher Morris 2 Posted March 3, 2020 Author Share Posted March 3, 2020 Ah! Robin, didn't think of CF rods. I will buy some anyway, as they will be useful. How have you found fitting Clevis & clap screw on this type of rod. Certainly a lot less on cost. Martin, it looks like normal clear plastic tubing. Quote Link to comment Share on other sites More sharing options...
Robin Colbourne Posted March 4, 2020 Share Posted March 4, 2020 Christopher, I haven't tried carbon pushrods myself, I've always used snakes, or, in the old days, 1/4" square balsa pushrods (which I wouldn't recommend). On throttle linkages, I've used bicycle bowden cable inner with soldered-on snake ends, in tube similar to those in your picture Given that carbon rods have unidirectional carbon fibres, I would think that using the clamp screw type connector runs the risk of crushing and splitting the carbon fibre rod. I would be tempted to use snake ends epoxied on with 24hr epoxy, after thoroughly abrading and cleaning (with IPA or meths) the end of the cut to length rod and the inside of the snake end (if you can get a needle file or broken Abrafile into the snake end to abrade it, so much the better). Only do one end at a time, so the position of the first snake end is fixed before attempting the second. Gently warming the snake end once it is on the carbon rod, will ensure the epoxy thins out and wets into abraded carbon. If you drill a hole in a piece of wood the size of the threaded end of the snake end, then put it in a vice with the open end pointing up, you can stand the carbon rod in it vertically. The epoxy will then form a nice fillet and not run down the rod. When you do the inner one on the model, slide the rod in from the tail and have the model pointing nose down to do the same. You can have the snake end attached to a clevis and the servo arm on the servo, so that end is fixed. The weight of the carbon rod should hold it in place, or you can rig up a rubber band at the other end pushing it in. Edited By Robin Colbourne on 04/03/2020 10:57:08 Quote Link to comment Share on other sites More sharing options...
Christopher Morris 2 Posted March 4, 2020 Author Share Posted March 4, 2020 Thanks Robin for the info, being a bit new to all this i will look into the snake side of things as it seems to have the good alternatives of many ways to fix them.. IE: (solder, glue & crimping" which all give me different ways to solve a problem. So, i don't think a few snakes & fittings will not do any harm in the arsenal. Thanks Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted June 13, 2020 Share Posted June 13, 2020 Maybe too big, but the Balsa Cabin sell 16 swg Den, that's 1.6 mm The trouble with steel 1.5 mm wire, this comes readily in coils and needs to be pulled straight Quote Link to comment Share on other sites More sharing options...
Pete B Posted June 13, 2020 Share Posted June 13, 2020 Posted by Den Moran on 13/06/2020 09:48:33: Hi, hope you have that sorted! Meanwhile, can anyone tell me where I can buy plain old 1.5mm mild steel rod, in one metre lengths, please? Hi Den, You'd probably get a better response if you start a new thread - put '1.5mm mild steel rod' in the title and you'll be bound to get a quick reply! Pete Quote Link to comment Share on other sites More sharing options...
Christopher Morris 2 Posted June 13, 2020 Author Share Posted June 13, 2020 Sorry, mistake. Edited By Christopher Morris 2 on 13/06/2020 10:27:58 Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted June 13, 2020 Share Posted June 13, 2020 The seagull wire rods are very heavy and require quite a lot of weight at the front balance them . Good idea to change them for snakes as already said. Quote Link to comment Share on other sites More sharing options...
flight1 Posted June 13, 2020 Share Posted June 13, 2020 You can get carbon rod for linkages from lots of model shops in 1m lengths and some specialist suppliers 2m and even 3m lengths. get the right threaded coupler glued on for joining your rod makes nice push rods see here for them and 1m lengths of rod from them too brc models 1.5 mm carbon rod in a sleeve much better than steel and lighter Edited By flight1 on 13/06/2020 11:31:37 Edited By flight1 on 13/06/2020 11:54:16 Quote Link to comment Share on other sites More sharing options...
Geoff S Posted June 13, 2020 Share Posted June 13, 2020 I use 3mm carbon tube which has a 2mm hole and glue in normal 2mm push rods with epoxy. They're light and very stiff, even unsuppported, at 750mm. I use a ball joint at the servo end and 2mm stainless clevises at the horn. It makes a very neat installation. Geoff Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted June 13, 2020 Share Posted June 13, 2020 Chris I appreciate you are working with an already built model but at some point the weight of really long rods/snakes is better addressed by simply moving the servo towards the tail or in the extreme putting the servo at the tail with a short direct linkage! It is mechanically more efficient so the servo can be smaller/ lighter and still generate the same force on the control surface. Just saying. Quote Link to comment Share on other sites More sharing options...
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