RC India

RC Models => Kites, Trains, Free Flight and All Others => Topic started by: K K Iyer on June 09, 2016, 08:44:31 PM



Title: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 08:44:31 PM
Hi everyone,

Too hot to fly. Too windy to fly. No field to fly in. Illegal to fly.
So what can an old aeromodeller do?

Build a small rubber powered model!
Inspired by the build quality of Mike Stuart (ffscale.co.uk), Walt Mooney, Dave VTO Linstrum, Steve WMD (outerzone)

Since my printer died, can't print plans, so make do with rough measurements from pdfs saved in ibooks!
Making outline drawings, then designing the structure based on own experience...

Started on 1st June. Today (9th), got the Pilatus flying inside the house.

Yet to build the undercarriage, wing struts, lettering etc.
17gms with prop and a little rubber. Will end up around 22gms with U/C, more rubber, nose wt etc.
Span 15", chord 2", length ~9"

Will post build details/problems/pics if anyone is interested.
Regards.


Title: Re:
Post by: sanjayrai55 on June 09, 2016, 08:58:04 PM
Cute! Pretty good for an old old aeromodeller

Sent from my Mi 4i using Tapatalk


Title: Re: A small Pilatus Porter
Post by: RCNeil21 on June 09, 2016, 09:02:14 PM
Great build sir :hatsoff:


Title: Re: A small Pilatus Porter
Post by: vineet on June 09, 2016, 09:19:39 PM
That is some neat build , i miss these types of posts now a days . if i had it i would have put a 5 gram brushless ,all in one rx and 1s lipo .


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 09:52:29 PM
@sanjayrai55,
Before I had even posted the msg, RC Aunt asked me 'Rai Saheb ka jawab nahin aya?'

Aa gaya. Thanks.
Thanks to Tarneil too.

Now I have an excuse to bombard the forum with inconsequential details!
So here goes...

Outline drawing made from approx dimensions from outerzone/Dave Linstrum/peanut

Now Peanuts can't exceed 13" span, and need 1/16sq wood.
That's too fine for an oldie to handle.
So made it 15" span.
And took 2mm sheet (from gajjark) and stripped 2mm sq.
Fuselage sides in 2mm sq looked gross, so sanded them down.
A syringe with 1cc of CA lasts only an hour or so before it clogs up...

(Refuses to take 2 pics in one post!)


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 10:07:30 PM
@vineet,
About adding RC, you may like to see my OLD threads on TLG1 (FF) and RG TLG...

Adding one pic at a time


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 10:14:11 PM
How to ensure fuselage is square without a jig?
Use desi jugaad.


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 10:19:17 PM
Then you stick the sides together...


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 10:23:20 PM
With fuselage, stab and fin done, cut the ribs..


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 09, 2016, 10:31:24 PM
Wings didn't seem stiff enough, so added truss...


Title: Re: A small Pilatus Porter
Post by: SI74 on June 09, 2016, 10:50:52 PM
I Love this build log....


Title: Re: A small Pilatus Porter
Post by: sanjayrai55 on June 10, 2016, 11:08:32 AM
Waiting for the video Iyer sir  8)


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 10, 2016, 09:07:19 PM
Learnt/relearnt several lessons:
1. Don't use old tissue. Get fresh.
2. Check grain of tissue. Turned out to be along thr shorter side of the sheet. Wrong orientation resulted in tail/fin covering being not fully taut. Far better result on fuselage with grain lengthwise.
3. Gum that comes in a transparent container that looks like a felt pen worked fine for attaching tissue. Has to dry fully, else will loosen during water spray.
4. Colin bottle spray not fine enough for water shrinking of tissue. Reverted to age old method (dip toothbrush in water, shake it to get rid of almost all the water, then strum the bristles with your thumb to get a fine spray.
5. Don't use old thinner, get fresh. My old thinner made cotton wool like clouds in the dope, which i stirred and stirred till i got a slightly milky colour instead of a honey colour. Thought the thinner was a year or two old. Looked up the label just now and found mfg date of Dec 2009! How time flies...
6. Water shrink / dope one wing panel at a time. Pin over packing at corners till fully dry, to avoid unintended warps / introduce washout. (Notice excessive washout in right wing? Had to be corrected in second coat.
7. For such a small model, thin the dope a lot. 50:50 was too thick.
8. Incorporate some method of adjusting incidence / fin alignment. Notice groove in fuselage for fin widened and packing added to correct slight right rudder
9. Such models apparently have the wings glued to the fuselage. Didn't dare. So used rubber bands to retain wing at the cost of some weight penalty.
10. Peck Polymers 6" prop was grossly out of balance. Needed 5" of black tape to balance!

Better stop now. This post/thread seems like a soliloqy of a rambling old man...

Next post will be after i figure out a detachable undercarriage, and then to test flying...


Title: Re: A small Pilatus Porter
Post by: SI74 on June 10, 2016, 09:20:01 PM
Great going sir. As short as an iPad! Stimulates me  :) to try my own! 👍🏻


Title: Re: A small Pilatus Porter
Post by: SI74 on June 10, 2016, 09:28:23 PM
I still haven't assembled my "Flying Machine" After I bought it, didn't care to assemble because I became passionate on RC flying :)


Title: Re: A small Pilatus Porter
Post by: prabal276 on June 11, 2016, 03:39:07 PM
Sir; great going. I am on a excursion and got 2g airtel signal right now. I'll be back on the 13 and will get back with the measurements you have asked for.
Regards


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 15, 2016, 10:36:28 PM
15" span, 9" length, 17gms with about ~2gms rubber.
12" loop of 1/8" Super Sport rubber, 6" Peck prop, ~120 turns.
Outside wind speed around 10-20 knots all day, so stuck indoor.

https://m.youtube.com/watch?v=7Pid_S5dsfA


Title: Re: A small Pilatus Porter
Post by: SI74 on June 15, 2016, 10:47:49 PM
Flies good👍🏻👍🏻... Waiting for maiden outdoors..


Title: Re: A small Pilatus Porter
Post by: manojswizera on June 16, 2016, 10:53:29 AM
Iyyer sir, good flight

Lighter note...
Nice target practicing.  ;)


Title: Re: A small Pilatus Porter
Post by: sanjayrai55 on June 18, 2016, 06:28:41 PM
Nice one sir  {:)}

What is a Peck prop?


Title: Re: A small Pilatus Porter
Post by: K K Iyer on June 18, 2016, 08:15:22 PM
Thanks SI74, Prabal, Manoj, Rai saheb.

@sanjayrai55,
Sir,
Peck Polymers (now has a new owner) is one of the old established (1971) suppliers of rubber power models and accessories. Attached pic of what I got.

@prabal276,
http://www.rcindia.org/kites-trains-free-flight-and-all-others/guillows-pilatus-pc-6-porter-kit-304-build-log/
What happened to your Pilatus?
If you have no time to spare, and need someone to build it for you... (Hint, hint  ;D)
I have 195ml of dope, 490ml of thinner, and a nice soft brush left over from my build!


Title: Re: A small Pilatus Porter
Post by: sundaram on June 19, 2016, 12:09:40 AM
Inspired to make one RC powered following you sir. Awesome build and nice flight. Need to learn the dope and tissue technique from you. Got a lot of balsa scrap still left.


Title: Re: A small Pilatus Porter
Post by: prabal276 on July 01, 2016, 07:48:43 AM
Sir;
the pilatus is gathering dust.
I have been doing a balsa build. Its for the school. They wish to get a solar aircraft for some silly competition, and i am doing that right now.
will be posting a thread once succesful.
Thanks for the offer but; i will commence on the pilatus after my fa2 test series.
Regards.
since ; i get to keep the plane myself; ill strip it off its electronics and will rcfy the pilatus


Title: Re: A small Pilatus Porter
Post by: K K Iyer on January 07, 2017, 08:53:04 PM
Wants to go out, I think...

https://m.youtube.com/watch?v=QGTn2ISaBU8


Title: Re: A small Pilatus Porter
Post by: Glidiator on January 07, 2017, 09:44:45 PM
Great test flights KK.

Seems more than trimmed and ready for a proper outdoor session.

Where did you source your Peck prop.

In my search for carbon rods came across this firm

www.aeroncomposite.com

Has a range of rods, tubes, sheets, fabric etc and a large range of propellers.

Prices on higher side compared to carbon rods I got from RC Bazaar, but range of stuff is wide.

Who all coming for Outdoor Nationals at Udaipur



Title: Re: A small Pilatus Porter
Post by: Glidiator on January 07, 2017, 10:02:22 PM
Next on my to do list is to make a twin prop rubber powered outdoor. Have been advised by the Hippocketaeronautics experts that a good model to start would be the Double Top.

Here is a post from Hippocketaeronautics on use of a Torque Meter for Twins to get the right thrust on both engines

A tad long -- but wort reading and going to the linked references for more info

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
I have been using a torque meter for the last year or so in flying my models and have been absolutely delighted with the results. This has all been with single engined models and I started after flying with Don DeLoach for a number of years and watching his overall success with flying scale models in general. At a Geneseo Nats a couple of years ago I was his mechanic as he won 5, yes 5, mass launches in a row. I was astounded and after being hit over the head with this 2X4 I figured I could learn something from his methods. Like all the guys in the FAC he was more than willing to share his knowledge and techniques and among them is the use of a torque meter which he learned from flying competition free flight. He subsequently published 2 articles in the Flying Aces Newsletters entitled "One Flyer's Approach to Better Performace", Part I and Part II and found in the Sept-Oct 2012 and the Nov-Dec 2012 issues. These articles, if you want to really up your performance and enjoyment, should be absolutely memorized by a modeler. I have read them again and again to get the concepts in my head. In the articles he makes the case why torque measurement is so much more USEFUL than counting turns. I have since taken my expensive turn counter off my winder as it really does me no good after using a torque meter.

In a nutshell, a torque meter tells you what power is going to come out of the nose accurately and reliably every time. It does not matter what kind of power you have in your model whether it is neatly braided 1/8" strip, an inner tube, a broken motor, or squirrel running in a cage. The winding is done to pack all the available winds that could possibly be put in the motor and what that number is, is meaningless as you can't get any more in anyway. Guys will say "I am flying on 1200 winds" which is smoke in the air as it is 1200 winds of what? 2 loops of 1/8"? 10 loops of 1/4" And how long? 8", 15" 36"? all have differing effects on the released power. The number of prior flights has an effect as with each winding to 1200, the released power goes down as the motor get tired. I will let you read Don's articles. I subsequently had an article published in the FAC newsletter too on how to trim a model using a cook-book approach and a torque meter titled "Torque, Trimming, Voo Doo and Beethoven". I can't remember the issue but if any one wants it, email me and I'll send it.

So, on to twins. I at first was leery of it as reading a torque meter is a moving needle and at first glance, the discrimination on the face of the meter doesn't look fine enough for get a consistent reading. In practice it is not an issue. As the torque goes up the needle does not wiggle but is locked hard at whatever torque is under strain at the moment. You only need to read the units to halves anyway, i.e. 4.0 inch-oz, 4.5 inch-oz, 5.0 inch-oz and so on. Both motors of a twin can be wound to practically identical torques reliably as a result. Even if you have mixed motors or a fresh one in one nacelle and an old one in the other, you can launch knowing that the pull power in both are matched even after many flights. You just cannot get that by counting winds as continual flights will weaken motors unevenly and you will have turn problems that defy solving......or at least I did.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Incidentally I use my self made torque meter during my indoor flights and have a log that has a record of Torque to height of climb to ensure that my model remains just below the rafters.