Closed loop rudder post - brazed

[Mike Quinn 2]

Hello

Because I'm kit bashing this TF Corsair 60 into a pseudo F2G with bubble canopy and tall tail and I want to go closed loop on the tail I need to make a rudder torque rod that has a double horn on it for the closed loop.

Can't see anything like it on the net. Anyone know much about brazing and how to do one offs?

Cheers

Mike

[Mike Quinn 2]

See the brazed elevator torque rod ... I need to make up something similar for the rudder but with a double sided horn for closed loop.  Ignore the one with the white sleeve.  No good for closed loop. 

Edited By Mike Quinn 2 on 21/10/2017 11:17:12

Edited By Mike Quinn 2 on 21/10/2017 11:18:56

Edited By Mike Quinn 2 on 21/10/2017 11:19:22

Edited By Mike Quinn 2 on 21/10/2017 11:19:58

Edited By Mike Quinn 2 on 21/10/2017 11:20:51

[Martin Harris - Moderator]

Silver soldering (this is a low temperature brazing method not to be confused with silver bearing soft solder) would be the way to go. Make a horn out of brass - drill a hole for the operating rod, clean everything spotlessly, coat the area you want the solder to flow to in flux and heat to cherry red, apply the silver solder and it should flow all around and inside the joint. You should be able to build a nice fillet...

However, as if I'm not mistaken, the linkages are all internal on the full size, why do you particularly want to go to closed loop? It is probably the best method technically, but not totally necessary on a model of this type.

Of course, you could really bite the bullet and model the F2G version with the split rudder - which applied a deflection to the lower part when the flaps were lowered past 30 degrees!

[Mike Quinn 2]

Hello

You've got a point ... I just prefer closed loop on rudder and it would be internal. However, the more I look at the carbon pushrod option I might just go that way for both elevator and rudder in which case I have single ended torque rods that would do it.

To be honest, trying to keep weight down at back end whilst increasing it by fitting the Robart retractable tail wheel. Means there's not much room at the back end. Closed loop would have helped with congestion and interference.

So if I went down the SilverSolder route ... what gear would I need ... just a small B&Q blow tour h, some brass sheet, 3mm brass rod, and any recommendation of the silver solder and flux ... and anything else?

Cheers

mike

[Martin Harris - Moderator]

There's no reason why you can't use steel (even stainless!) for the torque rod. It would be lighter and a lot stronger than brass rod.

Any normal blowlamp should do this sort of job.

I managed to get hold of some ready fluxed silver solder but it's (apparently ) rather expensive.

Unless you're acquainted with a refrigeration engineer, something like this seems a good start - no recommendations but Johnson Matthey is the go-to name...