RC India

General Topics => Chatter Zone => Topic started by: K K Iyer on February 03, 2021, 08:03:21 PM



Title: Schoolmaster- a modern version
Post by: K K Iyer on February 03, 2021, 08:03:21 PM
Hi everyone,

The story goes like this:
1. I want to build a model for my wife, the RC Aunt. Shes competent with Electric Power Gliders
2. Want to use a brand new OS 10LA, sitting idle in its box last 10 years. (~180watts)
3. Really want to use that.
4. If that is not enough, I could use my 40 year old OS Max 20 (~250w?). Recently got it back from a newbie Id lent it to long ago. But Id prefer the OS10.
5. We lost our lovely field with a mown grass runway, air conditioned hangar, runway lights etc for extraneous reasons.
6. Last weekend a College let us use one of their fields. Slightly small and somewhat rough.

I was thinking of building a 39 Ken Willard Schoolboy.
After considering a Royal Coachman, TriSquire, LiveWire and everything in between.

But today a friend sold me 4 sheets of 1/16x4x48.
And I have six 1/8x1/8x24 bass spars that I got in a hardware store in the USA two years ago.
Just right for a 48 wing!
Seems a pity to cut it all down to 38-40...
Have just enough 2.2mm sheet for the fuselage.

Cant decide between the 39 Schoolmaster and 48 Headmaster...
(Id probably add ailerons anyway)

Of course I could build another long pending project, the 48 DB Apprentice.
With a Cox Babe Bee, but I want throttle control.
Or a 50mm EDF, but I want GLOW.
(All my models are electric, except for a single Supertigre 40 powered SoloStar)

So,
40 or 48?
OS10LA or vintage OS MAX20?
BTW, its windy here ALL the time!

Thanks for inputs.
Regards
Iyer


Title: Re: How to decide what to build?
Post by: sanjayrai55 on February 04, 2021, 05:41:36 AM
Frankly Iyer sir, Willard is overrated!

The best designer of those days was undoubtedly OK Model Pilot's Matsumoto

I strongly recommend you build one of the QB Series:

QB 15H (suit your 20 )  https://outerzone.co.uk/plan_details.asp?ID=2327    (can add ailerons if you want)
QB 20 H (for your 20 )   https://outerzone.co.uk/plan_details.asp?ID=3613  ( reduce wingspan by 1")
Junior 100 (for your 10 ) https://outerzone.co.uk/plan_details.asp?ID=2374 (44" span)

I've built all of these, and they fly right off the building board!! And fly beautifully - stable and predictable, yet competent to do simple aerobatics



Title: Re: How to decide what to build?
Post by: sanjayrai55 on February 04, 2021, 05:53:39 AM
BTW, I'm completing a QB 40 Shoulder that's been lying around a long time, had just started it then abandoned


Title: Re: How to decide what to build?
Post by: sanjayrai55 on February 04, 2021, 06:36:17 AM
From RC Groups



Title: Re: How to decide what to build?
Post by: Free Flight on February 04, 2021, 10:51:08 PM
I think the key statement you made is that " BTW, its windy here ALL the time!".

No matter which model you choose, you have covered the basics in all: High wing, Tricycle gear, ailerons, use the bigger motor so you are not blown around. Looking back so many years ago, what my club has picked for me was a larger plane that flies slow giving me enough time to react and a wide throttle range. They had recommended that I build and learn on Sig Kadet.  So I l did just that.

Quote: "The Model should be a stable and easy-to-fly, ideal for the novice pilot learning R/C. Since it will fly hands-off - free flight fashion - when trimmed out. It is even possible for a new flier to teach himself how to fly without the assistance of an expert. A rugged balsa construction that allows it to take the punishment. The structure should resists fatigue and vibration damage."

Having said that, go with your 20 size engine and just wait a bit longer for your 10 size, another model will come along. I waited 15 years for my OS 10 La, now using it to teach myself CL flying on Streak (India Peacemaker, same designer) and is working out well.

So go with your initial intuition. I recommend your thoughts for the "Headmaster" Meets all your requirements and is an RC teacher called the "Headmaster"

https://outerzone.co.uk/plan_details.asp?ID=1917

Wish you the best


Title: Re: Schoolmaster- a modern version
Post by: K K Iyer on February 23, 2021, 07:37:59 PM
Finally got started.

Made templates for ribs.

Made trailing edge(1/4)/ aileron (1) by tapering a 1.25 width of 10mm balsa.

Luckily I have a Master Airscrew mini plane and a few new blades.
Else quite difficult to make tapered TE/ ailerons



Title: Re: Schoolmaster- a modern version
Post by: shirsa2001 on February 24, 2021, 09:50:36 AM
 {:)} Pls share build videos if possible. Would be a great help for aspirant balsa builders.


Title: Re: Schoolmaster- a modern version
Post by: K K Iyer on February 24, 2021, 07:29:20 PM
{:)} Pls share build videos if possible. Would be a great help for aspirant balsa builders.

The build process is too slow for video. But Ill post pics as I go along.


Title: Re: Schoolmaster- a modern version
Post by: shirsa2001 on February 24, 2021, 07:53:52 PM
That would be great. Waiting for more pictures....


Title: Re: Schoolmaster- a modern version
Post by: K K Iyer on February 24, 2021, 08:54:24 PM
@shirsa2001,

If youve seen the earlier posts on RC GROUPS youll know that all the gurus on RC GROUPS said it will be overpowered with an OS 10 LA.

Recommended was an 11% increase. From the original 39 plan on Outerzone.co.uk

Unfortunately the best my print shop could do was 100%

I did print a 111% version at home, but it was 28 pages of A4. Too much to paste together.

So I decided to go with the original size.

Then the question of rudder/elevator/throttle or ailerons.

RC AUNT, the missus, is already competent on basic trainers.
Wanted to put her on to an aileron model. Hence ailerons.

Well see how it goes...



Title: Re: Schoolmaster- a modern version
Post by: shirsa2001 on February 25, 2021, 08:39:42 AM
 :)  Best of luck for RC AUNT.

There is a free software called inkscape that helps a lot on enlarging or reducing the plan without changing the paper size.
We use that to scale up FT plans which were designed for around 4.5mm foam boards where we have 6mm.