Build: Kimball-Somenzini Python 100

[3-d flyer]

Reza, unbelievable what happened to this thread.......
I just wanted to say thanks for all your hard work and time offering us this info!
I am just waiting for the call that they are in and hopefully i'll make the cut on the first run! I have been looking forward to this one for awhile now and have been watching your build. Plane looks fantastic! and i am eagerly awaiting the vid and flight reports! Hats off man! Great job!!!

[3-d flyer]

	Quote: Originally Posted by JeremyHolt
	Reza picture looks great! Cant wait to see that thing with graphics also! Lets get back to the build thread..... one quick question though, just exactly how thick is the vertical fin?

LOL!!!!!!!!!!

[Vahn]

	Quote: Originally Posted by JeremyHolt
	one quick question though, just exactly how thick is the vertical fin?

I saw this in real life on Sunday morning at Blackstar in Socal.

When Reza wasn't looking, I took this measurement since it seems to be such a popular topic.

Will trade for 100CC sized Yak or Extra RTF.

[bnaderi]

Reza,

Keep up the good work buddy. Lets get on with the build thread.

[50%plane]

	Quote: Originally Posted by Vahn
	I saw this in real life on Sunday morning at Blackstar in Socal. When Reza wasn't looking, I took this measurement since it seems to be such a popular topic. Will trade for 100CC sized Yak or Extra RTF.

LOL!

Sweet thread Reza! Thanks for everything that you do!


WT,

I watched QQ fly his at the Fly For Tots a couple weeks ago. Truely amazing! I can assure you, if you have any doubts about this plane being poorly built, or a poor performer, you can kiss it's rudder. QQ rung it out and it asked for more.



50%

[Reza]

Thanks very much guys. I appreciate all the kind words.

Vahn,

I knew you were up t no good.
OK I have a 100cc Yak, let's make a deal. LOL

[Reza]

Rudder Servo Installation.

Install the servo the way that output shaft is towards the aft of the aircraft.
There are two tubes already installed in the tail section for you to guide your wires through it. This has been the quickest rudder installation that I have had. Cross the cables.

Rudder hardware comes with crimps.

Pivot point to the hinge line should measure 1 1/4" and use the 1 1/4" holes on the arm.

You can not mount the nut come with the Dubro hardware as the control horn is almost touching the stud.

[Reza]

Next is elevator control horns.

I used the Dubro nut and washer for elevator. DO NOT epoxy because it is very tricky to get the control horn on the bolt. Why?

Because control horn is really long and the hole is very close to the fuse therefore you can NOT turn the control horn over the 8-32" bolt. You have to hold the control and turn the socket head bolt.

You see what I'm saying I got lucky just plain luck because I wanted to epoxy the elevator just like the aileron but luckily since the surface was flat I said it would be easier just to use the Dubro package and that saved me!!!

I need to go in the garage and check my notes on the distance from hinge line to pivot point of the control horn. I think it was less than 1.5" even though I am using 1.5" servo arm.

[Reza]

We are pretty much done with the plane except for adjusting the throws, CG, Power System and receiver.

One thing before I get to powersystem options and 2.4 set up.

The bottom wings obviously have servo and extenstions. We need to get the servo extension inside the fuse. Here's what you need to do to accomplish this, it is easy.

Make a little cut just a little bigger than the plug in fuse where the wing root is going in. It is just balsa sheeting but you need to cut where the plug is coming out of the wing when you connect it. See pictures.

Then mark the wing and make the same cut in sheeting of the wing. Don't worry it is not structural and won't be seen when you install the wing because it goes in the fuse opening.

So when you are installing the bottom wing you will first pass the extension through the fuse and pull the extension then slide the wing. It will be alittle tight but will be OK.

[Reza]

This Python is extremely sensitive to where the CG should be. It is not as forgiving as mono planes.
It is fairly easy to CG this plane and this CG that I am about to give you will work in both 3D and precision. You do not have to have 3 kinds of CG with this plane.

From the leading edge of the bottom wing 85mm towards the trailing edge which will be right on the spar where the balsa sheeting ends. Do not pick the plane up from the wing tip as it will break the sheeting. If you move your finger a little forward you feel the hardwood spar that's where you and your helper should pick up the plane.

Now Quqiue's plane ended up balancing with batteries 5" aft the rudder tray. That's why there is battery tray provided with the kit for you to glue behind the turtle deck.

My plane balanced perfect with battery on the tray. Here's the differences in what we used.

Quqiue's plane:
Tru-Turn 4.5" P-51 spinner solid back plate
4cell NIMH 2700

Mine:
Mejzlik 4.5 Extra spinner
2cell 2150 Li-Ion Duralite

My plane should be about 5-6oz lighter than Quique's My receiver batteries are on the rudder tray.

[Reza]

Ok it's time to talk about battery selection. You are more than welcome to do any battery set up that you feel more comfortable with but here I will only discuss the ones I would use and have had experience with.

I had 3 choices of batteries and all are made by Duralite:

1. (2) 4300 Li-Ion
2. (2) 3000 Li-Po
3. (2) 3000 Li-Mn

Now specs:

Duralite Li-Ion cells are capable of delivering 2C discharge rate of their capacity so that makes 8.6amp Max discharge rate for one 4300 2S2P. These batteries are very stable and can give you almost 2 years of flying. Weighs 7.5oz with 16g wire and Multiplex or dean connector.

Li-Po: 20C discharge rate, Very light but flammable. Very sensitive to over charging or discharging. Weighs 6.5 with 16g wire and dean connector.

Li-Mn: 20C discharge rate at very low voltage drop, 10C charging if you can find a charger do that. NON flammable and heavier than Li-Po but not much. Weighs 7.7 with Dean or Multiplex connector and 16g wire. These batteries last longer than Li-Po and a lot less sensitive with over charge/discharging. When they burst you will see poweri material come out of it. Truly non flammable and you can charge them in your plane with no problems.

Now my Python is set up with (7) 8711 and AR9000 2.4 receiver. I need to choose a system that when my servos are taking 3-3.5amp at the same time my powersystem can take those spikes with minimum voltage drop so the Li-Ion in compare to the other were not the best option I had. Between the Li-Po and Li-Mn I went with Li-Mn for the peace of mind and not worrying about the charge or taking the batteries out of my plane while charging.

Now on the regulator side. I need at least 15 amp continuous regulator. I had two options again two New Duralite High Current regulator with 16 g wire all the way through or Powerbox.

I will continue on this with picture hopefully tomorrow evening. I can't see the monitor anymore TIRED!

[Reza]

So the options were Powerbox or dual HC regulator. Quique flies his with y-harness and no matchbox. He says that you won't notice the difference if the top and bottom wings of one side is about 2-3 degrees.

I put the powerbox on my scale and it was about 5.5 oz, 2 HC regulator with 16g wires were about 4.8 oz. The SC-12 also has built-in matchboxes. Since I had an SC-12 I went by that instead of 2 HC regulator.

Cost wise the difference is significant. This will be your choice or anything else that you are interested in doing.

The New HC regulator has 16g wire until right before the receiver! It has a dean connector and an adapter that converts the dean connector to two 22 g output. You can use only one if you choose to but if you have two open channel then you are better off using both. The length of the 22g wire is about 2" so it is short and voltage drop through it is minimum.

[Reza]

I have been flying my 10X with 2.4 Spektrum DSM2 module for about 2 months now and love it. I have set up this plane with AR9000 and two remote receiver. Location of the receivers are very important. I started with following location and luckily based my data logger I had minimal fades and no frame losses. One is located at the turtle deck and the other one lower part of forward of the fuse on the right hand side when looking from pilot's seat

[Reza]

If you guys use 6 8611a and one 8711 for rudder, you can get by using one high discharge battery such as Li-Mn and HC regulator. I have done numerous testing on my Yak-54 with above condition and current will not exceed 7amp, voltage drop on high discharge batteries are minimal in compare to Li-Ion as well. One of the main reason I went by all 8711s is to continue my testing with all 8711 in an airplane and monitor in flight current/voltage drop for the sake of comparison with 8611a. I know what I should expect but rather see the data for myself.

[Reza]

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