The flying monkeys got me...

Helis and fixed wing

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Saturday, February 4, 2012

Sbach is back

Though I suppose you never knew she left. For a blogger I suck at remembering that an event is blogworthy or that a photo would explain a lot... A couple of weeks ago I built my Hobby King Sbach 342 1000mm v2. What I failed to blog, probably because it pissed me off, was that I maidened her. It was a ADHD moment that we survived, only to learn she has a flight characteristic I shouldn't be surprised she has.

So all excited, after flying everything else I had brought out, I decided it was time to set off with the new Sbach and maiden her. I had set everything up a few days before. I installed the battery, checked CG, did control surface checks, set her to mid rates, and powered up for takeoff! She rolled out sweet, taking a bit of field which at first I thought looked under powered, but once airborne she hauled booty! The small wheels in tall grass didn't help her rollout. I thought she was a bit tail heavy and god almighty twitchy! The slightest input had an incredible response! Everyone stood at the fence giving me advice, but I figured out what she needed, brought her around and landed her sweet. I took a look at her and everything was fine... but thought, geez, that's a lot of throw for mid rates. Checked my DX8... crap.

I hadn't set any rates or expo... I was flying her at 100% with zero expo in all rates! Fixed that and took her back up. Even with 50% and 30 expo she was still twitchy but controllable. It took a few passes but I trimmed her out. She flew sweet! Great responses, no ill flight characteristics, even a clean stall with a long glide, though she does like speed better. Since I was still using the same battery I brought her in for landing. I figured that much like my Electrifly Cosmic Wind she would need some speed on landing, and on the first pass she came in a bit hot, and I went around. The wind swung around from a cross wind to from the south, so I made my second approach into the shifting wind. A foot above the ground she stalled when the wind changed to a brisk cross wind again and I got caught behind the power curve. The right wing touched, she cartwheeled touching her nose and coming to a stop without a full revolution, more of a rough landing than a crash. Yay! Everyone agreed she should be fine. I picked her up an noticed that the motor was bouncing around in the cowl... the cowl was still attached, but chipped up where the spinner had struck it. There was no other damage. This was a slow nose touch, and the the firewall punched through!

At home later in the week I quickly repaired the firewall and strengthened it. That was easy. The extra space of the new firewall moved the motor a hair forward so I was able to remove 2 of the washers I had on the shaft to allow the spinner to clear the cowl, so now there is more adapter on the shaft. I used Bondo and repaired the cowl, painted it (learned that there is white primer and it works so much better when using white gloss, which turned grayish with the gray primer). Put that all together this evening, tested her motor and controls, and she is flight ready!


Repaired the firewall/motor mount. You can see the cross wise popsicle stick. Much sturdier.



I realized that the wheel pants weren't going anywhere, so removed the wood spacer crap I had put in there and put a wheel collar on the inside. Much freer wheel spin!



The redone cowl (should have gotten a pre pic...). In the background is the rebuilt pod for the Thunder Tiger eHawk 1500 whose rebuild I introduced earlier,  but more on that later. Damn fine work!



All pretty and ready to fly! I think she is going to fly wicked nice!

3 comments :

  1. Awesome! I am building my HK Sbach 1000mm v2 as well. Can't wait to maiden flight her!

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  2. Thanks and good luck! Don't be afraid to really dial down those rates! I usually fly 75-100% rates at 25 expo, and I think I have dialed he low rate down to 35 with 30% expo.

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  3. Oh, and check my latetest posts on her... that gear box is weak.

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