Padawan micro slope soarer

[joe yap]

is this slope soarer easy to built and fly if so i may consider trying a glider after my miniT

Yes, they can be. But the range of slope soarers can range from very simple foamies or depron ships to very expensive and high performance composite slippers. It is all your own choice.

For beginner, you can start off with simple balsa or foam 2 channel birds like gentle lady or Easyglider (3 channels). You may be expert in some other form of R/C flying, but I'll still suggest you go for something quick and surefire way to start off with, as you'll have to learn to how to fight and make use of the winds which is totally new to most. Don't forget, you won't have power to get out of trouble.

[joe yap]

Hi Joe,

I've got a couple of questions and hope you'll share more of your techniques and materials used:

What do you use for filling voids before sanding down and painting again?

What type of spray paint do you use? I know you've stated that the final coat is a Tamiya Acrylic, so is the same one used before the final coat?

Also, which primer do you use?

Thanks!

For bigger voids and gaps, I use either epoxy or car body putty. If strength is needed for fillig big gaps, I chopped fibreglass cloth into very fine powdery consistency with a pair of scissors and mix it with laminating epoxy. For filling pin holes, I just paint the entire part with a thick coat of automotive primer, let it cure fully and wet sand it down with very fine sandpaper.

However hard you try, you can almost be sure to get some imperfections after spray painting the part for the first time, and to achieve better finishing, I always sand it down again until very little paint is left. The paint itself will be the micro filler for those porous surfaces and pinholes. Just before re-spraying, wet sand the entire surface with very fine sandpaper again.

I tried 2K paint but for quicker jobs, I used Tamiya Acrylic paint in form of spray cans, for the paint itself and a coat of transparent clearcoat. Also I used Tamiya white paint primer just before the yellow paint in this case, as thier paint is quite translucent. No need to do so if you use 2K paint as it is much more opaque.

Okay, after reading your post again, I think I need to tell you that there are 2 kinds of primer I use. The automotive primer I have is dark grey and fast drying, but best of all, it is sandable which makes it good for filling surface imperfections. The Tamiya white paint primer is just to produce a matt white surface for the topcoat colour to show. If you use the automotive primer prior to Tamiya paint, you find that you have to spray plenty of coats to make the colours even.

Sounds like a lot of job, isn't it? I can tell you, yes it is, if you want it to look really good.

[joe yap]

Not all the effort you put in will gurantee the same rate of success in return. Both Johnnie's and my models revealed the same problem. It seems that the wings are working too hard and flight controls did not seems to response as what you would like them to be.

After launching, the models sails beautifully for quite a moment, suggesting that the CG and pitch stability is spot on. But due to the lack of dihedral, it will not travel stright and level for long before the model starts to veer off course and naturally the pilot will roll the wings back to level again, which is when the problem starts. Even with whatever differential we had dialled in, the corrective inputs do not immediately give you the desired response and the thing you know, it started to over-correct the roll itself. Admist of this juggling, the models also started the porpoise as the airspeed changes. As we fought the controls in attempt to tame them, things just seems to get worst.

My model eventually decides to go for a suicide dive, and even when I tried to save it by pulling the elevator while its nose is pointing straight down, the pitch control did not response any bit until it smacked itself onto a rock. The wing rod is badly bent, and a wing is slightly crumpled, along with equipment breaking loose from their mounts. Due to the lightweight, damages are not too bad and it'll fly someday again, only that at that time, it'll have wingerons and elevator controld instead of pitcheron.

The verdict is; crap control system, but nice airframe design. I believed that if the controls are fully dependent on the wings, and once they are stalled, you'll lose them. But if you have a separate pitch control, you will still have it even if the wings are stalled, which you can at least attempt to unstall the wings.

This Padawan may become a Jedi one day, if some changes are made.

[buckman]

Wonderful! You've got the answers I've been looking for. Thanks!

[gEcky]

Hey Joe,

the automotive primer u mentioned is a 2-part one? Or does it come ready to use? Any recommendation on where to get? Thanks!

[joe yap]

Hey Joe,

the automotive primer u mentioned is a 2-part one? Or does it come ready to use? Any recommendation on where to get? Thanks!

No, it is only one part and is ready to use straight from the can. I got it from Tonita, 50 Paya Ubi cresent.

[gEcky]

Thanks Joe!

Do get this baby up and flying again!

[joe yap]

I took out the ill-fated Padawan, that I built 2 years ago, and started modifying and restoring the airframe. The damaged right wing is repaired and re-filmed. The newly fabricated vertical fin is epoxied onto the fuselage. The deep scratches on the fuselage paintjob were blended and given another few coats of paint.

The main modification is on the seperate wingerons and elevator controls, instead of the original pitcheron control. The new horizontal stabilizer has an elevator cut free, hinged and connected to a servo epoxied deep into the fuselage. The pitcheron controls on the wings were converted to wingerons with only serve to roll the model. A single servo actuating the bellcranks does the job.

This configuration add some weight on the tail, which should help to achieve the correct CG. This model has a long nose and I have to use very small battery previously to balance it, which can only provide rather short flight time. Now, I can pack a 600mah Nimh battery on the nose w/out the need of any ballast.

The AUW is now heavier, but still within good wingloading for our local slope and at least can have practical battery capacity.