Topic: Armstrong Whitworth AW38 Whitley

Pictures of the rudder improvements. The outer horns are brass strip, doubled over the piano wire hinge and soft soldered. (I have cleaned up the excess here too since the photies...)
 
The centre horn is a brass tube soft soldered onto the centre pivot and the other end flattened with two holes drilled for each of the rudder pushrods...

Trouble is John is how do I get it in front of the hinge line?

Are there any mass balance horns on the full size that could be modelled?

Are there any mass balance horns on the full size that could be modelled?

Ah, good idea, i'll go and research....

I can see them on the rudder but not on the ail or elevator

Steve

I can see them on the rudder but not on the ail or elevator

Steve

I agree Steve, from my googling it looks that way..

I will fly it as it is with the linkages "beefed" up and see what happens....

WISH ME LUCK CHAPS! 

Good luck mate, should be fine

I've been through my 3 view and books again and there is def no external mass balancers on the ail or elevator

Steve

Beefed up Rudder already, now here is the supported Elevator...

Right, bearings are in, and it's removed the 1/2 or so slop down to 1/8 each way. So that will do for me.

Basically I put pine supports under each side or the joiner where I could, and glued these with Gorilla Glue (PU Glue). Used this as the access is very difficult and the surroudning areas are weak and not level and at angles to each other! So the glue foams, spreads the load and fills the gaps. I will dremel away the excess once rock hard...

The supports each have a 2mm slot that the wire runs through. And then square plates are glued over once in place...

Changed the mini servos for Hitec 645s.... and connected them up to the receiver for a test....

Elevator is now absolutely perfect so that is job done. Got excited a bit!

Rudder worked fine for about 30 cycles.... Then gradually the travel reduced and ended up with about an inch of slop!

The problem is the one bit I didn't replace and that's the rear fulcrum that converts the fore/aft push rod movement into the crosswise pushrods to the rudder. What I had thought was a block of hardwood supporting a alloy tube as a pivot block, was actually soft balsa face top and bottom with 1/32 ply....

So all that happened is the alloy tube just started to moved back and forward in sympathy with fore/aft pushrod and compressed the 1/32 ply...

And to get the block out will result in destroying all the fine balsa ribs that it attached too...

So I think I will need to fit the servo in the rear in place of the fulcrum.....

The problem is the one bit I didn't replace and that's the rear fulcrum that converts the fore/aft push rod movement into the crosswise pushrods to the rudder. What I had thought was a block of hardwood supporting a alloy tube as a pivot block, was actually soft balsa face top and bottom with 1/32 ply....

So all that happened is the alloy tube just started to moved back and forward in sympathy with fore/aft pushrod and compressed the 1/32 ply...

And to get the block out will result in destroying all the fine balsa ribs that it attached too...

You could try soaking the balsa block with thin cyano to harden it then use an epoxy filler to hold the tube in place. If there is access then add a layer of glass on top of the ply to add strength.

Jim

You could try soaking the balsa block with thin cyano to harden it then use an epoxy filler to hold the tube in place. If there is access then add a layer of glass on top of the ply to add strength.

Jim

Unfortinately the block was mostly destroyed before I realied what was happening (it is buried deep in the tail!) Just leaving a damaged eopxy mass on the two inner rebs. 

What's the score with this now?

I would say 1-0 to the Whitley

I would say 1-0 to the Whitley

yes, but it's only half time.... 

What's the score with this now?

There's about two weeks (part time) work to get this done. And I must get as far as I can on the Tiffie before I move house. Coz if I were to move tomorrow, then the Tiffie is not far enough ahead to get done for summer '12. I hope to get the balsa bashing on the tiffy done by after the Christmas break and then move on to the glassing. Once the glassing is started then I will drag out the Whitley and carry on in parallel. But if I sell the house then it's all change!