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Old Jul 31, 2009, 07:12 PM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
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beetyiis Sukhoi Su-26 M3

THE LOOK

Here is my little Su from the beginning (SU 26)


till now (SU 26 M3) ...



SU 26 M3 :
The Sukhoi Su-26 made its first flight in June 1984, the original four having a two-bladed prop. The production switched to the Su-26M, with refined tail surfaces and a 3-bladed Hoffman prop. Further refinements were made, and the model won both the men's and women's team prizes at the 1986 World Aerobatics Championships. The modified Su-26M3 with the new M9F 430-hp engine dominated the 2003 and 2005 Aerobatic World Championships as well as the 2004 European Championships.


The first thing I wanted to change was the colour scheme, lightweight but the opposite of a beauty ...
Thinking of a paint scheme that looks good, almost easy to see, lightweight and easy to realize, I come to this solution - white (best colour to see when far away and light because no paint is necessary) and red in contrast because I like this two colours side by side.

Painting this scheme is not really easy so I decided to take a lightweight foil (ORACAL 751 premium plus - for lettering cars and trucks in real live). The gloss of this foil gives you an extra bling bling in the sun - hoovering in the evening sun is a blast ...
The extra strength for the elevator is a second plus.

Some tests had shown that this idea was a right decision - even in the evening sun and far away you are able to see where it wants to go.




Some issues


After I finished the painting I wanted to do an other improvement - I didnīt like the little ground clearance, so i tested some props.

This was one of them (50/30/x3) nearly same power like the original prop but a lot of ground clearance and very good looking ...


In comparison the GWS 50/43 with a custom made scale look - my favorit when it comes to power...



Another issue is the weakness of the ruder and elevator, so here are some improvements that I have done to them to get rid of their weakness and to precise the aerobatics.















THE CENTER of GRAVITY


Second improvement were done to the cg. Didnīt like it to be nose heavy as it was out of the box. So after some testing, reading here, testing, reading, testing, i decided to bring the cg at 36-37 mm.

To do this without flying with death weight, i had to redo the position of the electronics.



I made a little frame from 3mm Depron









here i have to remove some of the styro for the mainboard and made a carrying through for the battery cables






the mainboard went into the front of the wing and the aileron servo find its place at the end of the wing.



as you can see I neednīt to lenghten the original cables of the aileron servo






here you can see the pushrod for the elevator on his way through the plane, passing the aileron servo



ruder and elevator pushrods shortened and assembled with the original z-linkage



I extend the wiring to the motor with some thicker cables to prevent needless electrical resistance



To make a long story short, this was the right thing to do !

The other tested prop is an 50/43 that i have flown today with the improved
cg at 36,5 mm - yeeeessssssssssss.



You canīt believe the radical change !

It runs so much faster at full throttle - unbelieveable, seems to be a new plane and it runs fast and precise through the figures like never before.
Even vertical rolls are no problem, vertical isnīt endless but enough for having massive fun.

Knife edge seemed unpossible when I first started but now it is - very precise and straight !
3/4 throttle and 3/4 to full ruder and it goes straight so long as you want it to ...

Oh men what a blast - I have a new plane !

Iīve enjoyed the flying this evening so much, canīt waiting for tomorrow to test the new cg with the original prop and the 3 bladed 50/30.






THE POWERTRAIN / PROPELLER

Today I tested the original prop 6.25/2.75 (1.7gr) versus the 5/3x3 (2.2gr) versus the 5/4.3 (1.8gr).


All I have to say is screw the 5/4.3 on your plane - itīs by far the best in all areas except perhaps for static hoovering !

You donīt believe that it is the same plane - outstanding...

Vertical out of the hand the original prop has some more thrust, but when it comes to dynamic flight figures (vertical from normal flight, loops, vertical rolls) the 5/4.3 is so much better !

Loops are very clean and straight, rolls are very fast even in a vertical flight.

You can do knife edge with ease given that your cg is right.

Level flight with less than half stick.

Flight time seems to be a bit shorter - perhaps because with this prop I like it to roll vertical all the time ?!?

Gliding is much better, too.


The 3 bladed 5/3x3 has a little more rpm, speed and dynamic vertical range than the original prop. Static thrust is lower - flight time is compareable with the original prop.

Limited knife edge is only possible at the beginning of your battery because of 0.5 gr more weight to the nose (cg to the front) and the decreased speed.

Gliding is compareable to the 5/4.3.

All figures are slower and not so straight - but it is by far the best looking prop...



The original prop only has some small advantage at static thrust.
Only very limited knife edge at the beginning of your battery because of the low speed. Very little ground clearance.

I come to the conclusion, that our planes need some more speed for aerobatic - that makes the trick.





TIPS and TRICKS

Reading that everyone is searching for an prop adapter and would certanly like to have a nice spinner without the weight of the plastic ones,

I decided to show you my way to adapt the GWS props to the prop shaft and how to make a nice spinner that even protects your plane when hitting the earth (in a wrong way) with the front...


Here is all you need



First I take a 1,2mm drill and shrink tubing.



You have to make some experiments of adding shrink tubings with a different thickness to get the right diameter for the hole of your prop.
After shrinking the first tube, peel it off and than stick it back onto the drill - this will make it easier in the end to get the drill out of the tubing.


Ad one shrink tube after the other perhaps you want to glue it with CA but it is not necessary.



When you reached the right diameter for your prop, pull it off , clean the ends and your adapter is finished.



Now you can stick it into your prop and glue it with a little drop of Ca on both ends. Screw it on your prop shaft and you are ready for take off...







Well i know what you are going to say - now I have the prop on but it is ugly without a nice spinner...

Spinner made from plastic or rubber are too heavy in your opinion ?

Letīs make a nice spinner as you like it - lightweight.

First we need some styrofoam like it is in the box of your Sukhoi.

Cut a piece of it and stick it on a drill, cutter or grindstone.





Take a piece of fine sandpaper (600-800) to round it like you want.


Now you can even channel it a bit


With a drop of UHU POR you can glue it to your prop - ready !


Itīs much nicer with a spinner...









Some photos from the evening flying today ...


nice cruising






vertical


knife edge in the air...


... and near the ground - did I mention that I love knife edge ?!?



Isnīt she a beauty ?!?




more to come ...


Rolf
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Last edited by beetyii; Aug 17, 2009 at 06:40 PM.
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Old Jul 31, 2009, 07:31 PM
shutup and tell me
PA
Joined Mar 2008
282 Posts
NICE! is that the foil you were talking about? i want a link to the styff as it seems to work great
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Old Jul 31, 2009, 10:24 PM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Like I said above the foil is made for lettering cars and trucks in real live - very thin and relative light unfortunately not very cheap, perhaps you ask for some leftovers...


Rolf
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Old Jul 31, 2009, 11:15 PM
JWs are Shear Fun!
Aerogance's Avatar
USA
Joined Sep 2008
2,682 Posts
Nice build. I like how you were able to combine several benefits into a single mod (the foil for example). I really like how clean your installation is. It looks like you had to lengthen your motor wire and shorten your control rods...win-win: Less weight, tighter linkages. Thanks for the nice pictures and clear description of what you did to the plane.
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Old Aug 01, 2009, 09:18 AM
The thruster don't work!
Roy E Oetting's Avatar
Fairborn, OH
Joined Oct 2002
415 Posts
Looks great! Interested to hear your flight reports.
Roy
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Old Aug 01, 2009, 10:33 AM
Experienced R/C Repairman
barnyardflyer's Avatar
Three Oaks, Michigan
Joined Sep 2003
2,597 Posts
I received 2 5030x3 blade props by a mistake in shipping from GWS Props. (I ordered EP-5030)

I am very interested how yours will work after your mod.

Did you liked the 5030x3 better than the 5043 before the mod? That was the impression I got anyway.
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Old Aug 01, 2009, 07:22 PM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Thanks for your comments.

@Aerogance

I like to make the best out of a given thing with the smallest effort. That is meant not only for the technical side but also for the optical.
A nice looking plane is the start for me and then i try to take it to his technical limits (and above).




Today I tested the original prop 6.25/2.75 (1.7gr) versus the 5/3x3 (2.2gr) versus the 5/4.3 (1.8gr).


All I have to say is screw the 5/4.3 on your plane - itīs by far the best in all areas except perhaps for static hoovering !

You donīt believe that it is the same plane - outstanding...

Vertical out of the hand the original prop has some more thrust, but when it comes to dynamic flight figures (vertical from normal flight, loops, vertical rolls) the 5/4.3 is so much better !

Loops are very clean and straight, rolls are very fast even in a vertical flight.

You can do knife edge with ease given that your cg is right.

Level flight with less than half stick.

Flight time seems to be a bit shorter - perhaps because with this prop I like it to roll vertical all the time ?!?

Gliding is much better, too.


The 3 bladed 5/3x3 has a little more rpm, speed and dynamic vertical range than the original prop. Static thrust is lower - flight time is compareable with the original prop.

Limited knife edge is only possible at the beginning of your battery because of 0.5 gr more weight to the nose (cg to the front) and the decreased speed.

Gliding is compareable to the 5/4.3.

All figures are slower and not so straight - but it is by far the best looking prop...



The original prop only has some small advantage at static thrust.
Only very limited knife edge at the beginning of your battery because of the low speed. Very little ground clearance.

I come to the conclusion, that our planes need some more speed for aerobatic - that makes the trick.


Rolf
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Last edited by beetyii; Aug 15, 2009 at 05:12 PM.
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Old Aug 01, 2009, 07:56 PM
The thruster don't work!
Roy E Oetting's Avatar
Fairborn, OH
Joined Oct 2002
415 Posts
Without actually testing the three bladed prop I totally agree with your assessment, Rolf. I'm using the Zippy 240 mah cell and am looking forward to trying the Hyperian. Thanks for the report.
Roy
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Last edited by Roy E Oetting; Aug 01, 2009 at 08:50 PM.
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Old Aug 01, 2009, 10:16 PM
Registered User
Torx's Avatar
United States, TN, Memphis
Joined Apr 2007
1,693 Posts
im thoroughly impressed by your mods.
especially the decals.

i would like to know the exact brand of sheeting you used.
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Old Aug 01, 2009, 10:40 PM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
The foil is named :

ORACAL 751 premium plus (for lettering real cars and trucks)


Rolf
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Old Aug 02, 2009, 07:01 AM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Double posting please delete ...

Thank you.
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Old Aug 02, 2009, 09:33 AM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Reading that everyone is searching for an prop adapter and would certanly like to have a nice spinner without the weight of the plastic ones,

I decided to show you my way to adapt the GWS props to the prop shaft and how to make a nice spinner that even protects your plane when hitting the earth (in a wrong way) with the front...


Here is all you need



First I take a 1,2mm drill and shrink tubing.



You have to make some experiments of adding shrink tubings with a different thickness to get the right diameter for the hole of your prop.
After shrinking the first tube, peel it off and than stick it back onto the drill - this will make it easier in the end to get the drill out of the tubing.


Ad one shrink tube after the other perhaps you want to glue it with CA but it is not necessary.



When you reached the right diameter for your prop, pull it off , clean the ends and your adapter is finished.



Now you can stick it into your prop and glue it with a little drop of Ca on both ends. Screw it on your prop shaft and you are ready for take off...







Well i know what you are going to say - now I have the prop on but it is ugly without a nice spinner...

Spinner made from plastic or rubber are too heavy in your opinion ?

Letīs make a nice spinner as you like it - lightweight.

First we need some styrofoam like it is in the box of your Sukhoi.

Cut a piece of it and stick it on a drill, cutter or grindstone.





Take a piece of fine sandpaper (600-800) to round it like you want.


Now you can even channel it a bit


With a drop of UHU POR you can glue it to your prop - ready !


Itīs much nicer with a spinner ...






Rolf
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Last edited by beetyii; Aug 17, 2009 at 06:38 PM.
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Old Aug 02, 2009, 12:34 PM
DFC~ We Do Flyin' Right
bsbauman's Avatar
USA, GA, Atlanta
Joined Nov 2008
14,479 Posts
Great work! I would love to see some vids!
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Old Aug 03, 2009, 07:20 AM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Hope to get a video in the next few days.

Here are some improvements that I have done to the ruder and elevator because of their weakness and to precise the aerobatics.













Rolf
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Last edited by beetyii; Aug 03, 2009 at 07:42 AM.
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Old Aug 04, 2009, 07:13 PM
Make the best of all you have
beetyii's Avatar
Essen/Germany
Joined Dec 2006
569 Posts
Some Photos from the evening flying today


nice cruising






vertical


knife edge in the air...


... and near the ground - did I mention that I love knife edge ?!?



Isnīt she a beauty ?!?


Rolf
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Last edited by beetyii; Aug 04, 2009 at 09:36 PM.
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