Ballerina by EarlyBird

[EarlyBird]

There are two ply plates one inside for the captive nuts and another on the outside.

The balsa you can see in your post is scrap to fill the void between the captive nut plate and the wing seat.

[Peter Miller]

If Early Bird has followed the instructions the blind nut are in plywood which is set parallel with the bottom of the wing and then he should infilled below the ply with scrap balsa.

[Steve Goodwin]

Ahh...and there solves the confusion, I only have a single ply brace in my kit, so I used it on the inside. I made the correct choice!

 

 

[EarlyBird]

8 minutes ago, Steve Goodwin said:

Ahh...and there solves the confusion, I only have a single ply brace in my kit, so I used it on the inside. I made the correct choice!

 

 

The inside one is 1/8" and rectangular. The outside is 1/16" and rounded also slightly bigger IIRC it is made up of two 1/32" pieces, probably with the fuselage ply doublers. 

[Steve Goodwin]

I have another question. Regarding the creation of a "T" to simulate vertical and horizontal stabs, am I right in thinking that the only glue surface for the scrap (to create the tail plane mount) is onto F10, this would mean an end grain surface for gluing, not the best me thinks?

 

 

 

[EarlyBird]

The temporary T is not glued just pinned in place. There is a 1/8" balsa triangle from F10 to the tail fitted with the top flush to the sides. 

[EarlyBird]

? the scrap balsa to form the fillets is only glued as you describe ? keep the T piece in place and be very careful once it is removed to fit/check the alignment of tailplane and fin. 

[kc]

Different people will have different ways to fit those fillets to the fin.   My way would be to sand fillets to shape using the scrap T pieces, then cover them ( if film covered ) and later attach them to the already covered fin.   Then glue fin with fillets to tailplane.  Tailplane would have been covered and affixed to fuselage with the glue fully hardened before I glued fin on top.  This would all give time to align tailplane parallel to wing seat and then fin vertical to tailplane and fitting flush to fuselage.    One joint at a time and let it set.   PVA or Aliphatic gives time to adjust the fit and wipe the excess glue off the film.  

Having seen a clubmates tailplane break in flight due to 'nicking' the balsa when trimming film to allow bare balsa for glue area - I am very careful to not make that mistake!

 

[EarlyBird]

When I first flew the Ballerina I did not understand this

I have only had three years flying RC and always electric. The advice was trim to half throttle which I have always done with a new model and adjust to taste with more flights.

I have gradually speeded up and consequently reduced the up trim. The other day I made a mistake because of an error I made during the build, I glued the snakes to all of the formers, I routinely check that I have a bit of up trim before flight but this time as by chance it was dead level I left it. On take off it did not leave the ground just skipped along until I gave a bit of up elevator. Reducing the throttle to 3/4 it flew level so I left the trims. It flew absolutely fine but I did notice that going to full throttle made very little difference in speed also if I pointed the nose up it continued at that trajectory. My initial thought was I like this. ?

 

The lesson I learned is not to trim to half throttle, I assume that was for novices to fly very slowly. Thinking again IC do not fly at half throttle or do they? I think not judging by the noise they make. A novice turned up for his first lesson with a Boomerang the engine looked too big to me. The instructor said nothing and I kept quiet and watched. For a glow two stroke it was fast and not at all noisy. I asked, not in front of the novice, it was a 60 size flying on half throttle.  

 

My conclusion is that for a model converted to electric with an equivalent size motor then trim to 3/4 throttle. More experiments to come I think.

 

Interesting.