HK401 Gyro modifications for use

The first time I used a gyro on an airplane was on a DWFoamies Yak 54 (which has now been added to the RIP list due to a bad servo horn, read more about it here). The gyro I used was a $12 Hobbyking favorite, the HK 401B. The only downside of using this gyro instead of a brand-name one is that it needs to be modified and enhanced a bit before use. Sergio Salvi explains:
Two major problems were reported in the G401B forum threads: The gyro circuit board is not firmly attached to the plastic case, causing problems to the gyro operation. The solder joints of the tiny switch for digital/analog/normal/reverse mode can break off the board when flipping the switches. Items required: Hot glue gun (I used a small 10W dual temp gun) Small piece of soft foam – 2.5cm x 2.5cm, about 0.8cm thick (1″ x 1″, 1/3″ thick)
He explains in detail the steps required to fix this plane, but here is an instructional video that will show you what to do exactly, step-by-step, to make this gyro usable.
Flying the DWFoamies 40" Yak 54 with the gyro on was awesome! Hovering almost too easy and knife edges were clean a piece of cake to perform. Just remember to set the servo switch to the type of servo you're using. I had it on digital with a cheap 9G servo and it fried it after about a minute. Beware!

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RIP: DW Foamies Yak 54

I like to offer a minute of silence for a lost airplane....[1 minute pause]. Goodbye DW Foamies Yak 54. I had a great time flying this plane. It was a great 3D trainer, and even better after installing a Hobbyking 401B gyro to help out with hovering and knife edge maneuvers. But where and how did I lose this plane? Well, something very odd happened in mid flight:
Lost Plane Report (LPR) I was on my 4th flight that day, the plane was behaving as expected and I was getting very comfortable hovering and doing knife edges. I tweaked my expo/dual rate settings to 50% expo 100% travel on acrobatic mode and 40% expo 70% travel for sport flying. I also had tweaked the gains on the gyro to 15% / 65%. When the plane was about 50 feet in the air after coming around after a round of maneuvers, I lost elevator control and the plane started drifting with the wind, which was blowing pretty intensely for a regular summer afternoon. I struggled with getting it back down using throttle, ailerons and rudder, but pointing the plane to a specific direction was becoming more and more challenging was the plane kept drifting further and further away. At that point the plane was well into the golf course next to the Apollo field (where I usually fly) and I was losing visual contact with it. The winds kept blowing pushing the plane further away and I finally lost visual contact with it.
Well, why did you lose elevator control? At the end of the flying day, I realized that I had forgotten to secure the elevator servo arm with the supplied screw after making last minute adjustments at home. ONE TINY SCREW! One forgotten tiny screw was the reason why I lost a plane to the wind. From now on, I double, scratch that, triple-check all my servo screws and connections before taking off. A lesson that had to be learned the hard way.

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