Just wanted to report back that I finally got a good ultra light setup working on my Sokol (ARC110, 4.1x4.1e, Rhino 3s1250 30C, Phx25 esc, 11.9oz AUW). First, the arc didn't smoke after 30sec of WOT like the Hacker, WHEW! LOL! It also landed warm but not dangerous (I'm running a himaxx 20mm heatsink on it). Speed seemed visually on par with my D99 (~130-140), but the Sokol is smaller so perhaps it was just 120 or so. I set my cg to 20mm and she landed like a trainer, LOL! Fun setup for those smaller fields... made me and a couple buddies dizzy following it around today.

I'll add some pics of my Sokol's paint job to this post. I got it with sky blue wing and stab bottoms, so I had to paint it just to see it. Now with the new paint scheme it was easy to track.

Cheers,
Kev

[edit: FYI, after flying my Sokol for some time now, I've found a CG of 25mm or greater is a better starting point. 20mm results in much faster landings, and requires a lot more elevator deflection to flare.]

oh sweet! yeah id love to see some pictures!

I added pics. I wouldn't have thought of shooting the entire underside of a pylon racer sky blue, but that's what I got. It was white on the tops of the wing and tail as usual. The paint job added 0.1oz. Now as you can see, I can see it no problemo.

Kev

Hey Kev,
You've already got a Sokol, but yet, you want another one??

No, one is plenty for now, and the way it flies I won't need a backup. If I had money to for another small moldie it would have to be a Voodoo, or Micro Stinger.

Kev

Hey


Check your EWD. I have measured at mine Sokol more then 1.5°, now i have reduce the EWD to 0.3° an the CG at 33mm. Flies very good.


Raffi

Raffi, thanks for the info! Interesting to hear you have it working all the way back at 33mm; I think that's 8mm farther than anyone else who posted. Just to clarify, does the acronym "EWD" mean decelage, or incidence?

My trim is neutral at 20mm, so I was planning on tuning the decelage as I venture farther back. I don't have an inclinometer though. A few test flight iterations would go quickly, but a starting point would be nice. Do you remember roughly how thick a shim you had to use for the -1.2degree change?

Thanks,
Kev

Hi

EWD= Angle of incidence

The angle between the wing and the elevator was more then 1.5° degrees by my Sokol.
So i reduce it to 0.3° and it flies with a CG of 33mm. Because the high angle is a reason for a CG of 15 to 18mm

Raffi
Sorry for my bad english

I have begun reconstruction on my sokol. I sanded for a good two hours yesterday evening.
I have heard that the fuselage section directly behind the wing saddle is a very weak point on pylon racers.. Has anyone ever confirmed or denied this? i want to know if I should reinforce weak areas on this plane.

Originally Posted by knifeedge63

I have begun reconstruction on my sokol. I sanded for a good two hours yesterday evening.
I have heard that the fuselage section directly behind the wing saddle is a very weak point on pylon racers.. Has anyone ever confirmed or denied this? i want to know if I should reinforce weak areas on this plane.

I did fly my Sokol for 4 years, rough landing and some bad starts , I was as new when I sold it, I didnt see any weak spots at all... But I did "only" fly it with 450watts. If you are aiming much higher, well then you will have to think in other terms..

Originally Posted by sebbe

I did fly my Sokol for 4 years, rough landing and some bad starts , I was as new when I sold it, I didnt see any weak spots at all... But I did "only" fly it with 450watts. If you are aiming much higher, well then you will have to think in other terms..

Im puttin in a Mega 16/15/2 on 3s.

hey can someone get a picture of the firewall/ motor mount for me? Mine came off and was lost, so im going to have to fabricate my own. But id like to make it just like the original.

Originally Posted by knifeedge63

hey can someone get a picture of the firewall/ motor mount for me? Mine came off and was lost, so im going to have to fabricate my own. But id like to make it just like the original.

Here you go Colin. Maybe you wanna glue the mount in w/ some down thrust angle, because the first time I glued the mount in, I had it at 0*, and the Sokol climbed at full throttle. Luckily I had a hard landing and the mount came loose, so I reglued it w/ some down, I'm guessing 3-5 degrees at most, and she goes straight and level at full throttle, w/ that Mega 16/15/2.

what size bolts are you using to mount the motor?

Put a couple of holes in the mount to let some air at the windings