1/4 scale swift kit - help please

[Cain]

Hi Roo

Thanks for your information, I was especially keen to understand that you have gone away from the mass balanced scale appearance of the elevator tips, I have yet to cut mine out so may now opt for the practical option!

Just had some fun (while looking after the kids this half term) and have taken a hole cutter to the fuz but all is good - I have calculated an incidence of between 1.5 and 2 degrees - but that is relative to the stab which is difficult to estimate. I guess once I have test flown it I could put some tape under the front/rear to adjust.

Nice to have the wings on at last and it will give me some enthusiasm (not that I really need it). BTW The wing join is a 12mm steel rod.

[Cain]

Canopy frame next

[Cain]

My good friend John H lent me his incidence meter, I set the stab level and have measured a +ve wing incidence of just under 2 deg. (Not bad as I had used my old maths and trig from 40 years ago).

Hopefully this will work ok. Simon, it is a very simple matter at this stage to reduce the wing incidence as fuselage hole for the wing root incidence pin can be made oval by around 2mm before fixing in place and reinforcement, so now I know where I am I think I will do this.

My fine Kevlar cloth arrived, it is cut at 45 deg to the weave so should be perfect for making the aileron hinges.

[Cain]

Guys, please can you advise how much load spreading is required inside the fuz, I was going to epoxy some ply plates around the wing tubes - do you think this is adequate. I was also going to glue a strut of wood inside the fuz inline with the leading edge, the idea is it will resist compression as the wings tend to come together ‘clap’ in a heavy (nose in) landing. Thanks

[Peter Balcombe]

Cain,
Your suggested approach looks reasonable, but please make sure that you use the appropriate resin type for your fuselage.
(I.e. Don’t use epoxy resin if you have a polyester resin fuselage!)
However, i would expect a Modellbau kit to be made using epoxy, so you should be ok.

[Cain]

Crikey, I never thought to check compatibility, thanks

[Cain]

Sorry, more help please

I have made up a rudder hinge with Tufnell eyes and a carbon rod as the pin. I am very happy but now am wondering about a concealed mechanism for connecting pull pull cable, it needs to be simple to attach as the rudder requires removal so the stab can be transported and attached.

Do you think a concealed mechanism is overkill, do they work ok and give decent resolution and power with effectively very short horns?


I have addded a screenshot of the topmodel version but it is not clear how it is done

Thanks

[Cain]

Spent a few happy hours making a mechanism to hide below the rudder, rudder still removeable (hopefully)

[Simon WS]

I have addded a screenshot of the topmodel version but it is not clear how it is done

Thanks

No magic there, if is just as you suspect - a very short horn on the rudder. And as you realise this potentially causes problems with centering, resolution and slop. However, in practice it is not a problem on my Top model Swift (after all the rudder isn't all that important in terms of the above - awaits incoming flack!!).
I have a larger scale Fox by Purbeck and the way they do it is much better imho - direct drive with the servo sitting beneath the rudder hinge line. However the way Topmodel do it is perfectly ok - this is likely to a model that is constantly being thrown around doing aerobatics so a perfectly centering trim is unlikely to be all that important

Simon

[Cain]

Getting nearer.