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YAK 55 M FOAMY (HK) + maiden - Printable Version

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YAK 55 M FOAMY (HK) + maiden - wingtipper - 07-04-2013

THE SRL EXTRA 330 FOAMY WENT DOWN TODAY ( FOAMY) .
pushing the boundaries of 3d practice . it was a great model .
thinking of replacing it with one of these ,
any advice on these.

http://www.hobbyking.com/hobbyking/store/__22413__Hobbyking_Yak_55_3D_1096mm_EPP_ARF_AUS_Warehouse_.html


http://www.hobbyking.com/hobbyking/store/__37608__Turnigy_Aerodrive_SK3_2836_1040kv_Brushless_Outrunner_Motor_AUS_Warehouse_.html


on 3s of course with a slow fly 10x4.7 or 11x4.7 prop .
better to push the boundaries with these foamies .

RE: ANOTHER ONE DOWN . - Steven - 07-04-2013

I have one of those Aerodrive motors (1050kv) in a rc Pajero. It's a torque monster for certain. Nicely finished, too.

RE: ANOTHER ONE DOWN . - wingtipper - 07-04-2013

yes i think i'm switching from ntm prop drives to sk3's . thanks steve .

RE: ANOTHER ONE DOWN . - secant0give - 07-04-2013


I would just build another one the same, Ummm that's just what I'm doing at the moment actually. I picked up a flat pack of SRL last weekend Smile

RE: ANOTHER ONE DOWN . - wingtipper - 08-04-2013

i took the easy way out mate . its all ordered and on the way .

RE: YAK 55 M FOAMY (HK) - wingtipper - 11-04-2013

WELL , i really think i'm on a winner here . how can you fault something like this @ $58 ARF + $14 Delivery . brought a nice motor for it @$23 4 hxt 900 servos a prop and a receiver $42 and thats if you buy everything . . i only had to buy the frame and motor , the rest is carryover stuff .
i dont recommend it if your not an intermediate builder , as it simply doesnt fit togather without modifying and compromising , wing spar was 5mm out of whack, undercarraige fits like bald man combing his one hair , and it could do with a little strengthening here and there . the prefab was wrong , obviously there arent quality control checks for fitment etc . wings simpy would not fit without re shaping and modifying .
but if your ok with building its no big deal .
the plane though for what you get is simply inspiring , infact i dont know how they can do em so cheap .
it's not finished yet . but heres a few pics . they speak 1000 words 1096mm wingspan .


RE: YAK 55 M FOAMY (HK) - wingtipper - 11-04-2013

final product . i had to add some spars to the rudder as it was flimsy , not in the pics . the good the bad and the ugly . the GOOD * - is its cheap and relatively nice looking well cut thought out model , plenty of hardware . skimping on nothing .
the BAD *- Design flaws and unmatched parts ,, easy to get around with a little thought ,modification and effort, servo arm extensions included which is a great idea , but 1.6kg load limit hxt 900 servos might struggle
the UGLY * - TAIL HEAVY . this model is designed for a 28-36 diametre motor , so i chose a 28 , to save weight . for this reason i carefully selected a 28-36 motor at 335 watts 35 amps , and it is too light for CG . i could use a 1800mah battery but battery compartment would need to be modded . thats just extra weight anyways , the idea was 1300mah .
HAD TO ADD 30 GRAMS OF LEAD AT THE FRONT TO GET IT WITHIN CORRECT CG LIMITS .
i would have to modify a fair bit to bring motor forward , so it's going up on its maiden to see how it flies with the lead on it .
flying weight 800grams +30grams . total 830 grams/ 30 ounces . Instructions say plane should come in between 690 - 760g , i'm 830g and i built as light as i could .

DATA: 3S 1300MAH , prop- 11x4.7 sf apc , esc hk 35 amp , motor SK3 1040 KV 28-36 3S , FLYING WEIGHT 830G . WING SPAN 1096MM CG 125MM ( 110-130)
32 AMP , 327 WATTS setting at 30 amps 300 watts for 830 grams. APPROX 170 watts/lb. 3d specs suggest 150-200w/lb
















RE: YAK 55 M FOAMY (HK) - gbanger - 11-04-2013

Don't worry to much about that C of G shit Frank, its a 3D model isnt it? Tail heavy is good...

RE: YAK 55 M FOAMY (HK) + maiden - wingtipper - 12-04-2013

MAIDEN FLIGHT , ^^^^^ THANKS GARY , YOU WERE SO RIGHT ON THAT .

had the maiden flight , needed the usual trimming and went ok , the landing gear fell out though as i hadnt glued it in i just wedged it with a paddle pop stick , but that came loose and she fell out . so i zapped it in for 2nd flight and all went well . i did 3 setup flights , adjusting throttle curve and throws between flights , also changing exponential , i increased the throws even though i'd set them up for max travel according to the instructions , <<< once again the instructions were wrong , as they supply servo arm extensions and then tell you maximum throws , where you end up reducing your travel on the servos <<< sacriligious in servo setup . but i was happy when i set them back to 100% .
the nose sage , i reduced half the nose weight , ie 15 gm and it made minimal difference , so i took all the lead off that i added - 30 grams , which brought back the model to 800grams even , mightn't sound a lot but 30grams of lead added 4% wieght to the model . so removing it and having a little tail heavy setup , rendered ever so slight down trim to keep model flying level , and inverted it is fine . very neutrally balanced , and soooo much better flying .
i had 9 flights all up most of it was changing bits here and there , and i think it is now close to a fantastic flyer . . power to weight seems spot on , battery life is only 4 min 30 seconds . but this thing can take off inside 30 cm and fly vertical , and land the same way . i really really enjoyed it .

i highly recommend this model with my setup for anyone training on 3d , or even as a 1st model trainer with a buddy setup . its a great beginner to advanced model , and when i came home i had a smile on the dial , and only 9 flights . i'll be back tomorrow .

RE: YAK 55 M FOAMY (HK) + maiden - gbanger - 12-04-2013

Very happy it all went well Frank... told you tail heavy was good (only for 3D though)