RC India

RC Models => Gas/Glow/Nitro Planes => Topic started by: Aeroresurrect on August 07, 2019, 01:27:22 PM



Title: T-40 Build 1540 mm
Post by: Aeroresurrect on August 07, 2019, 01:27:22 PM
Slow and painful build....
Instruction sheet supplied left too much gaps , had to overwork my brain to sort out more than 300 build components.


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on August 07, 2019, 04:33:49 PM
Is this from RCB?


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on August 07, 2019, 06:33:48 PM
No, from Aliexpress - scratch build model.
Still not clear how the aileron is to be built.  (Apparently instruction says to cut the outer 3 ribs near the trailing edge of both wings.... !)
The undercarriage is another big jigsaw puzzle.
Lets see how it works out...


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on August 07, 2019, 06:38:46 PM
1. This is termed " Kit Build"  Scratch Build is when you have a plan and sheets of balsa/ply
2. The aileron IS actually cut from a wing TE. This is common, nothing to worry about
3. Just play with the U/C parts, you'll see how they fit  ;D

Good luck, keep posting  :thumbsup:


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on August 07, 2019, 06:57:32 PM
Thanks Sanjay,
By the way, where do you stay in Gurgaon ?


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on August 07, 2019, 06:58:37 PM
See Reply # 12 here:

http://www.rcindia.org/electric-planes/piper-cub-from-rcb-balsa-kit-for-2014-sweepstakes/


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on August 07, 2019, 06:59:23 PM
Thanks Sanjay,
By the way, where do you stay in Gurgaon ?

In DLF 4. I'm 62 years old, semi retired


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on August 07, 2019, 11:46:06 PM
Hi Sanjay,
Just saw your build (Piper Cub) from the link you provided. It was a very, very neat and professional job (aileron separation from the wing). I guess the same procedure applies to my kit also.
Btw, I am also 61 years of age retired from active service, put up in Noida. My build takes time as all my components come from outside mostly sequentially (due to cash crunch). I don't allow leeway for wrong purchase.
I have another hobby (biking). Recently bought an Enfield Interceptor 650 (twin cylinder) at Kolkata. Again it is my endearment to IC engines which prompted me...
Shall look forward to meet u someday.


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on January 23, 2020, 08:41:47 PM
Servos in place !
Covering film just released by Kol customs after 4 months.
Engine mounting pending (tank awaited)


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on January 24, 2020, 05:12:33 AM
Coming along very well  :thumbsup:


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on January 24, 2020, 05:39:49 AM
But Projjal, this 4 months for the covering film is astounding!


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on January 24, 2020, 12:42:08 PM
Sanjay Sir,  this is the hard truth about our Customs. I had decided NOT to follow up.
Thank you for encouraging my build.
Should be bench-testing the engine soon.


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on February 01, 2020, 10:34:12 PM
Preliminary mount of the engine to assess cowl modification (mutilation) due to the muffler. I wonder if a long neck is available for the muffler ?


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on February 02, 2020, 05:08:27 AM
It could be possible to get a Pitts type muffler for it. But you'll have to search!

On another note, maybe it's an optical illusion, but the engine seems tilted to the left. Left thrust is the last thing you want; ideally for this model you should have a little (2 degrees) right thrust


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on February 02, 2020, 08:01:09 AM
I too thought so... (engine axis pointing to left). I will correct it by adding shims between mount and firewall.
But the "cowl-foul" is more complicated.... :banghead:


Title: Re: T-40 Build 1540 mm
Post by: K K Iyer on February 02, 2020, 12:05:07 PM
Just noticed the dry cells in a battery box.
This is a potential failure point due to connection break caused by vibration.
We gave this up decades ago.
Better to get a presoldered 4cell NiMH pack.

Regarding side thrust, perhaps you could elongate the holes in the mount a bit. By shimming behind the mount, you’ll lose the solid contact with the firewall that helps vibration absorption/damping.

Just my 2 cents worth...
Regards


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on February 02, 2020, 12:12:01 PM
Are they dry? Look like Eneloop NiMH. Anyway, Iyer sir is absolutely right: these battery boxes are shady!


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on February 02, 2020, 11:16:15 PM
Yes, Iyer sir,
Battery box is just temporary. I normally use completely encased boxes , tightly cello-tape wrapped all round. Wiring leads are soldered to switch and charging socket. These are not dry cells but rechargeable NiMH s  (giving about 1.2V per cell and having 1300 mAH or above capacity). In this airplane, I intend to use another battery box (size AAA- NiMH rechargeable - 1000 mAH for the CDI ignition system). So, 2 charging points and 2 switches !!
I use some rubber shims between firewall and engine-mount to absorb engine vibrations.


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on February 02, 2020, 11:24:25 PM
Sanjay, these are "Envie" rechargeable NiMH cells , 4 in series yield 4.8V at whatever ampere-hour (I never use less than 1000 mAH) found OK .
However for transmitter, I use 2500-2800 mAh of these cells as drainage is more.


Title: Re: T-40 Build 1540 mm
Post by: K K Iyer on February 03, 2020, 08:37:06 PM
However for transmitter, I use 2500-2800 mAh of these cells as drainage is more.

Sir, if you have a wattmeter, please compare the current draw by the Tx on constant use, with the draw on the airborne pack with intermittent but frequent use of the servos.

You may be surprised that the Tx pack needs far less capacity than the Rx pack!

I had typed out a far more detailed reply but it got lost between the back arrow and front arrow...

Regards


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on March 19, 2020, 01:07:17 PM
Thank you, Iyer sir, for the useful input.
I shall anyway upgrade (capacity) of receiver battery to 2400 mAH or more as I intend to use a 3-axis stabiliser also. (This entails continuous drain on battery).
Best regards


Title: Re: T-40 Build 1540 mm
Post by: Aeroresurrect on October 27, 2020, 11:26:03 AM
Some progress with film wrapping


Title: Re: T-40 Build 1540 mm
Post by: sanjayrai55 on October 27, 2020, 04:01:11 PM
 {:)}

Maiden it!