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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Flying at the Apollo Field – The Scratch-built Comrad 1

This is the first on-board video I've shot, and I did it on a totally scratch-built airplane, the Comrad 1, based on the Axon design by Ed from Experimental Airlines. The plane is made out of Dollar Store foamboard, hot glue and packing tape. It is powered by a Thunder Tigre .10 spinning a 7x5 APC propeller in a pusher configuration. It uses two 2200 3-cell batteries in parallel all the way forward, mainly to balance out the plane. Its equipped with four 9-gram servos (dual ailerons/flaperons, elevator and rudder), and an Orange 6 channel receiver, powered by the BEC circuit in the Turnigy 30 amp ESC. This is also the first foamboard plane I built following Ed's (from Experimental Airlines) Armin wing technique and folded square tube made out of foamboard. The plane flies very stable, the only inherent design flaw is that you need to shove a bunch of weight (or batteries) in the front of the fuselage to get the center of gravity right. It lands very gently and tracks like a champ. Have you built an Axon? What do you think? Let us know what you think in the comments.

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