Miniature Aircraft "Furion" Review


I will be using the Scorpion Hk-2221-6 and Scorpion's 55 amp speed controller along with the 11 Tooth pinion gear.

Scorpion Hk-2221-6 & 55amp Controller with programmer

Flight Power EVO lite 3s 2500

To The Building


This is the box The Furion 450 comes in. I'm using SAB 325 blades.

The instruction manual is now coming on CD. While this is a nice touch you will need to either have your PC handy during build time or print out approximately 89 pages of manual. Now 89 pages seems like a lot of building most of this is manual is photo illustrations to help with the building process.

Now I don't plan on covering every build step in the manual I will cover what I think stands out from it. One thing I can say is when reading the manual look ahead and read the next few steps and pictures as well. I found there was a few time I was reading behind the pictures and it can get a bit confusing at times. Keep track of the screws, you will use them all and if you find you have a few left over of different lengths, that just means you used the wrong screws some place earlier in the build process.

This is the open box of parts. All the bags of parts are numbered and in each back are bags of sub assemblies. This means that for all the steps all the parts you need are in that bag. You will not have to dig out of other bags. The only exception to this is the carbon fiber parts, they are separate.

I had a bit of "is this right" on steps 1A1k. I was wondering what is really going to hold these pulleys on besides the loc-tite? You use green loc-tite to hold the bearings into the pulleys, but there isn't any thing that backs that up like a bolt with a larger washer on it. However, it seems that you won't have to worry about this because these pulleys are not getting any "up / down" movements on them. So far so good.

Here are pictures of the Right and left frames. This is pretty straight forward so far. One thing I would suggest is not to loc-tite on the front battery tray for now, you can do that after all the electronics are installed. I found I was constantly taking this tray off and on during the build. I had it off to put the velcro straps in, route wires, install electronics and so forth. I would however install it for now so you can make sure every thing is square during the building process.


This is after installing 2 of the 3 servo's for the swashplate. I used Futaba S3156 digital servos in my Furion. They fit right into the mounting locations. These mounting locations are adjustable so you will be able to use a wide range of small servos on this helicopter. You can see the machining in the metal parts are pretty nice. Every thing was square and all the holes lined up between parts.

This is the Motor install. Again the mounting location allows for a wide range of motors and will allow you to adjust the gear mesh as well. As you can see I moved the pinion gear down just a little from being in line with the top of the motor shaft. I did this to make sure the main gear was running in the middle of the teeth of the pinion and also my thought was to make sure if there was any load it was as close to the motor bearing as possible. However I'm not sure that little bit would even be noticeable.

Here is the tail boom and gear box installed into the frame set. This gear box is fully ball bearinged and supported. Once built you will find it very smooth. In step 3a.6.d, you will be pressing in the ball bearings into the tail rotor pitch control ring. You need to be very careful on this step not to press in that ball bearing off center. It is very easy to break this bearing if you try to use any thing to press with that puts pressure on the inner race. DON'T try to use your screw driver or press. One thing I would suggest is use a small piece of hard wood instead of your ball link pliers as shown in the manual. This will work just be careful.

Here is the belt on the main gear. It all lines up really nicely and square, so you don't have to worry about any "up / down" play or a non true running belt. Just make sure that when you put the belt in you don't have any extra twists in it.

I used the futaba G401 gyro with the S9257 Tail rotor digital servo. Again the mount on the tail rotor servo is adjustable. You will pretty much need a smaller gyro to fit into the location provide. The G401 fits just right and has just enough room for the velcro security straps provided.

The main head being built. Again every thing is ball bearing and fully supported.

This is the swash plate and mixing arms.

Another picture of the main assembly area. You can see how the tail rotor belt runs in between the pulleys. Also the 3 swashplate servo.

The head design is pretty much a straight forward miniature design head. Fully ball bearing supported assembly.


These photos show the layout of push rods and servo arms. Make sure you end up with all your servo arms 90 degree to push rods and all is square. If you follow the dimensions giving in the instructions you will end up really close to perfect on all of this. The biggest thing is if your servo arms are not 90 degrees to the push rods. Again you can see the quality machining in the metal parts.


Pure the building instructions I placed the speed controller and receiver in the specified locations. The speed controller was behind the motor and the receiver was under the battery mount. Now what I came across was there was a bit of speed controller noise the the gyro picked up in this location. After a couple of test flights I ended up moving the rx behind the motor and put the speed controller up front.

Here is the new location for the speed controller and receiver After moving to the new location there was no more noise generated gyro problems. You can see after I moved the electronics, that I used small pieces of large ID fuel tubing. I cut a slit down the middle of the pieces and ran the servo wires through. This will eliminate any possibility of "chaffing". While in this picture I'm not quiet done cleaning up all the wires, you should get the point that you don't want any thing rubbing or touching any spinning parts.

One thing I did do was when I did my radio setups was to use an old battery pack. I also unplugged the motor and used a nicad rx pack and a switch so I could easily turn on and off the rx without any risk of damaging any thing.

My built Furion 450 with my Futaba 12z radio.

So after getting about 5 maiden flights in the helicopter is pretty solid for a small 450 size helicopter. One thing to get used to is the higher then "normal" head speed. With my 90 size Fury I'm running about 1850 head speed. On this small 450 I'm well into the mid 2000 head speed. The helicopter almost sounds like a turbine spinning<G>. I'm running about 25% expo on my cyclic commands and about 10% on my tail rotor as well. With the suggested push rod lengths I am pretty close to 100% on most end points. I did have to give one of the cyclic servos some sub trim to center the servo push rod / control horn.

Optionally if you don't have them all ready I would suggest the fly bar / pitch gage for these smaller size helicopters. Miniature Aircraft has a set that is made for this particular helicopter but the pitch gage would work on most smaller bladed helicopters as well. This makes the setup much easier and you are sure you are getting a linear pitch setup and recommended cyclic commands.