Stearman65 Posted October 14, 2018 Share Posted October 14, 2018 I'm at the start of the wing build on my Top Flite Stinson Reliant. The outer tube is made from cardboard & IMO very poor quality. The instructions call for it to be hardened with cyano at on end & a plug inserted at the other end. Before I used the cyano I tried the metal tube in the outer & it was a very tight fit, almost too tight to remove a wing without using force. I used cyano to harden the end & then couldn't fit the metal tube as the cardboard had shrunk. After a lot of work with a file & sandpaper I was able to fit the metal tube. So the question is, does anyone know a source for a replacement. The outer tube is 28.26mm & the inner 25.46mm with an electronic mike. The outer dimension is the critical one as it has to fit the formers & ply box which is already built. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted October 14, 2018 Share Posted October 14, 2018 Well first of all they are metric equivalents of imperial sizes. Inner at 25.46 is 1" Outer at 28.26 is 1 and 1/8" Just so we know. Getting precission cardboard tube is possible but not at all easy I've found you may get the nominal dimensions but there is considerable tolerances and in actually it may well be some way from what you expect - certainly enough to cause you problems in this case. Also, frankly, it not the best of solutions in tne first place. Personally I'd replace it with carbon fibre tube. It's lighter, stronger and is available in various precission sizes at realtively low tolerances. Just Google "carbon tube" and you will find many places offering it. Getting imperial sizes my be difficult, but not impossible. The only downside is that, naturally it a bit more expensive - but its a much better solution! BEB Edited By Biggles' Elder Brother - Moderator on 14/10/2018 09:21:15 Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted October 14, 2018 Share Posted October 14, 2018 Eric You can get the Phenolic tubes which is a far better solution than a bog roll inner!🤪👍🏻 **LINK****LINK** Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted October 14, 2018 Share Posted October 14, 2018 Yes indeed - heavier but cheaper! Also check out GRP tube - similar. BEB Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted October 14, 2018 Share Posted October 14, 2018 Absolutely BEB if it were on the performance gliders it would be Carbon, no question, I had forgotten glass tubes, there are quite a few alternatives to suit most pockets. Great forum for ideas👍🏻 Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted October 14, 2018 Author Share Posted October 14, 2018 Thanks for the suggestions chaps, however, I'm assuming I would have to replace the inner metal tube & the outer cardboard with a matched set of inner & outer tubes. What I don't want is to buy an outer tube only to find it is either too tight or too slack on the existing metal tube, I googled carbon tubes but out of the 6 I tried most went up in 3mm increments. As I said previously the outer diameter of the outer tube is the critical dimension at 28.26mm as it has to match the formers, doublers & tube box which are already part constructed, 29mm would mean altering the hole size which could mean misalignment between the fuselage & wing. Quote Link to comment Share on other sites More sharing options...
SR 71 Posted October 14, 2018 Share Posted October 14, 2018 I make my own outer tubes from fibre glass, i get the alloy tube from the local DIY cut it to length then wrap two layers of brown parcel tape around it then two layers fo fibre glass when cured i pull it off the tube then pull the parel tape out of the outer tube, the parcel tape has to be sticky side away fro the alloy tube for the first layer, the second layer go's on sticky side to sticky side with the first layer, Tony Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted October 14, 2018 Author Share Posted October 14, 2018 Posted by Nigel Dell on 14/10/2018 09:47:26: Eric You can get the Phenolic tubes which is a far better solution than a bog roll inner!🤪👍🏻 **LINK****LINK** I have sent a request to Falcon, thanks for the link. I seem to remember being in contact with them during my last stint of modelling 11 years ago? Thanks for the link. Quote Link to comment Share on other sites More sharing options...
Biggles' Elder Brother - Moderator Posted October 14, 2018 Share Posted October 14, 2018 Carbon fibre tube of the exact size you want (1" ID, 11/8" OD) does exist Eric, but you need to look at American manufacturers selling through UK agents. You won't get as a metric size. I fear that unless; you are very lucky, you have it custom made, or make it yoursef as SR71 proposes, you will have some fettling to do! BEB Quote Link to comment Share on other sites More sharing options...
Nigel Dell Posted October 14, 2018 Share Posted October 14, 2018 Hi Eric You are welcome, I have been here before and know what a pain it is, please see below for another option of a great retailer, they have helped me out of a hole on numerous occasions. **LINK** Quote Link to comment Share on other sites More sharing options...
Stearman65 Posted October 14, 2018 Author Share Posted October 14, 2018 Hi Nigel Yes I got my first batch of glues from Slec, wish I'd "stuck" (no pun intended) with them for the 30 minute epoxy I ordered subsequently, having a real toil sending it back. You may have seen my comments on my build thread? Regards Eric. Quote Link to comment Share on other sites More sharing options...
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