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Posted by cropcircle | Nov 13, 2014 @ 01:46 PM | 2,636 Views
Until now, I really liked the HXT900 servos. I use them a lot, on almost all of my planes.
Today I noticed that not all HXT900 are the same. Here's why:

I fitted a HXT900 servo on both flaps of my BIX3.
When I tested them, I found that one flap travels more then the other although they were both configured and setup the same way.
I did some investigation and found that there are some differences between the two servos.
At first I thought one of the servos was bad. I dug up some more servos from my stock and I found that there are two version of these servos.

The first thing I noticed is the different package.
Although they have the same P/N (662) the package and label are a bit different:
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A closer look at the servo showed a slightly different label.
The font is different and the margins around the "HXT900" text are not the same:
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The most noticeable difference are the arms and the screw that holds them to the servo gear.
One has a screw with a slightly bigger head and the arm has a smaller hole then the other one.
Also, the arm from one servo will not fit on the other one:
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Posted by cropcircle | Mar 23, 2014 @ 07:26 AM | 4,711 Views
The Dynam Waco comes in a very nice package. All the parts are individually wrapped in plastic, and the big box is divided into several smaller boxes. Only the fuselage does not come in its own box.
A manual is also included and has assembly instructions and ESC programming guide. Also included are decal sheets with very easy to peel stickers.
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Posted by cropcircle | Mar 17, 2014 @ 06:20 AM | 2,764 Views
I previously did some modding to the H-King FW190 landing gear. That modding did solve the nose-over issue, but I felt the gear was very flimsy and bouncy.
So I did a second modding attempt to install longer legs with larger wheels.

In order to install longer legs, I had to make a mounting place for the new retracts. I didn't want the retracts to be too far from the originals, because that would place them on a very thin part of the wing.
I cut the foam to suite the gears and placed two pieces of wood for the retracts to screw on.
I installed a carbon strip on the base of the retract well, to distribute the weight in case of a hard landing.
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I used Dynam FW-190 struts kit and retracts. I cut them to fit the exact length I needed. Their original length was too long for me. I also cut the plastic scale cover of the legs and fitted them on the metal wire. I reversed the plastic mounting screws so the legs covers are attached much closer to the wheels. Added some glue to keep them in place.
Some foam hacking was required for the larger wheels.
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Posted by cropcircle | Jan 15, 2014 @ 08:16 AM | 3,134 Views
A while ago I needed to replace the motor on my J3 Cub. Then I encountered a problem:
The stock motor has 16mm & 19mm mounting screw space, and all other 35xx motors (and up) have a 25mm screw space. Also, all the motor mounts I could find under 45mm, were 16mm & 19mm.
I searched quite a bit for a motor that might suite on the mount. I couldn't find one, so I started searching for some sort of a conversion to put between the mount and the motor.
I came across Fortis Airframes. They had something in stock that looked like I could use. I ordered it. I was then contacted by Zach from Fortis. I sent him some pictures and diagrams, and he was kind enough to produce, especially for me, exactly the device I need.
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It's a disc with holes in 16mm & 19mm, with supplied screws. And also holes for counter-sunk screws in 25mm spacing.
The disc is made of some pretty strong plastic (According to stress analysis, it can hold up to 200kg of thrust).

I used it to connect the Turnigy Aerodrive SK3 - 3548-700kv.
Because the disc is a bit thick, In order to connect the disc to the motor, I had to use some longer screws (10mm) instead of the ones that came with the motor.
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Posted by cropcircle | Aug 04, 2013 @ 03:37 AM | 3,445 Views
Some modding I did to the H-King FW190 1200mm.
I saw a lot of reviews saying this plane has a tendency to flip on its nose during landing. I decided to do some modifications to the landing gear, before I even flew it for the first time. Here is what I did:

1. Lower the tail:
I installed a smaller tail-wheel. It's a 30mm one I had lying around. I then bent the tail-wheel wire, as far up, towards the plane, as I could.

2. Rake the front landing gear forward:
I installed a piece of ply wood under one side of the retracts base. This made that side higher and thus giving an angle to the legs forward.

3. Install larger front wheels:
I replaced the stock wheels with larger 55mm ones. This gave a bit more length to the gears. These wheels required some foam hacking to fit them nicely in their place. Also needed to drill the wheel with a 3mm drill for the hole to fit the shaft.

In addition I replaced the stock ESC with a Turnigy Plush 60A. This ESC fits tight in the compartment above the motor. I had to cut some foam above and below the ESC, to allow air to flow and cool it.
I also painted the guns with a black mraker, to make them more "realistic".

The plane flew extremely well but more important, landed perfectly.
Check out the video of the flight and landing:
HK-FW190 1200mm Maiden flight (0 min 55 sec)

Posted by cropcircle | Jul 21, 2013 @ 07:27 AM | 2,863 Views
How i made my Bixler 2 into a funky disco bubble busting fun plane.

A few months back, I got the idea to connect a soap-bubble machine to my Bixler2.

I purchased, on eBay, a bubble maker designed for the WLtoys V757 Copter. It costs about 6$ including shipment and a bottle of soap.
The bubble pump itself is pretty small and light. It's designed for a very small helicopter, so it fits great on a big plane like the Bixler2.

The pump needs about 3.3 volts to operate. I wanted to connect it to a channel on the receiver to turn it on and off. I got a remote switch from HobbyKing. This device emits 5v when the channel is turned on. To bring the voltage lower to 3.2v, I used a 3A DC Buck Converter Setp-Down Module 0.8v-20v.

I connected the switch to the converter to the bubble pump, Turned the channel on and turned the converter dial, until the bubble burst was OK. I added an LED to let me know when the pump is active and soldered it all up.
Then just applied some hot-glue to keep all the soldering together.

I mounted the pump on the bottom of the Bixler2, covered it with an old AXN canopy I had lying around, taped it all up and went flying.

When on the ground, the bubbles are very impressive. It gives a steady stream of small bubbles, that fill up the area. Once in the air, the wind bursts most of the bubbles and unless it's dead calm and you're flying really slow, you'll only get a few bubbles reaching the ground.

The ingredients:
The bubble pump

Remote Switch

Buck converter