Category: airplane


Hello,

It was quite some time since I reflected on my Extra300 EPP indoor plane. The build was rather long and I had many questionmarks. I think this happened partly due to my inexperience in building and due to the manual being written by a very experienced senior pilot who mentioned only the most important aspects of the build. I am not even novice in building, so I would have needed a lot more detail in building instructions.

Anyhow, the plane is ready and it flies well. I tried to take a stepwise approach with flying. I knew that indoor flying would demand constant usage of rudder. While flying my Easystar I started to turn with rudder and aileron together. So I made some rudder practice to prepare myself for indoor challenges. However I knew that playing with rudder while having “the whole sky” to my disposal is rather easy. I was prepared for some crashes as I knew that indoor will be a lot more difficult.

To not ruin the plane within 10 seconds of flight I tried to practice on the ground first. That said applying a fraction of throttle and “driving around” in circles rather than lifting off. This was more difficult than I have thought it would be, since nothing was trimmed and I had a new radio system even. As result I had some occasional unintended takeoffs. These were aborted mostly, that said I crashed the plane nose-in to the floor. Like a warbird tip. I consumed propellers at some rate 🙂

Maiden flight:

2nd flight:

3rd flight, I started to enjoy high angle-of-attack slow passes. Not easy, but fun. Tried to mix directions, figure 8 and slalom flight. Very exciting to do, maybe not so exciting to watch, though.

4th flight, I tried to transition to hover.

5th flight, with hovering practice.

6th flight, more hovering and fun flight.

7th flight. I started to grow devil horns, had some “moments” of daredevil actions. Landed on the wall for instance.

8th flight, my first roll indoors. Scary but fun.

I skipped last weeks flights as I was fortunate enough to have my daughter born. She was born at 1:30 on the 20th of January 2014. A real miracle, 49 cm and 3230 grams of new life. Funny enough it is my birthday, I received the best possible present ever! I stayed home to help my wife and the baby, no flying right now. I will regain action soon, just need to sort out the first few weeks with helping around.

I am not sure what will happen to our outdoors flying. The flight club is going through a very difficult time period. The council announced that they will remove us from our flying field. As from 1st of February 2014 we are no longer allowed to use the field, we have to clear the area and cannot return. We haven’t received yet any other area to use, so the very existence of the club is in danger.
Our flight club and cross motorcycle (dirt bike if you like) club is removed from the area. The cause for this unfortunate decision is that an investment group tied to some politician tries to build a set of luxury golf flats in the area. It is rather interesting, since the golf club itself went bankrupt several times during the last few years. Besides that there are many issues around the build plans, as it seems politics and corruption got mixed up things quite a bit.

The club tried to apply for a negotiation, but the council does not really listen. So as for new it looks like that 1st of February is the end of our current flight activity.

I don’t know yet how we will do. There are some locations where I can fly, but the club itself will not be able to survive without a flying field. We will see.

An article from local newspaper.

With best regards,

Sir Crash a Lot

Hello,

I was participating at Winter indoor flights earlier but never could fly for real. I made some practicing with my Lama v3 helicopter and watched the others fly with their special indoor planes.

Now the time has come for me to join as a flying participant. I ordered a nice indoor plane and some matching electronics.

The plane is an Extra 300 made from EPP material. Has 830 mm wingspan and a high visibility colour scheme.

ap-e300-epp-3_9628 ap-e300-epp-1_9626

According to the description this can take some crashes without being converted to confetti. In my case this is not only a good plus point, it is more or less a basic requirement. I think I will need to get some good practice in simulator.

I found a clip where a really expert level pilot flies such a plane indoors. Amazing piece of piloting.

I will be happy to just fly around without touching the walls or other hard surfaces.

As for the electronics I went for the following list of components.

Turnigy 19 gram brushless motor.

2S 370 mAh battery.

HXT900 servos.

10A ESC.

GWS propeller. A lot of them to have spares 🙂

I planned to use my existing Turnigy 9X v2 radio with it. I have 4 extra receivers, got them together with the radio. Then I have got some second thoughts.

I was watching a lot of reviews about FrSky radios earlier and started to be interested. Rc Model Reviews had some great reviews of FrSky. They just launched a new transmitter, it looks like a very capable piece of kit. Maybe a bit too much for me right now, but I keep it in mind as a possible upgrade for later. My current knowledge and experience does not really need such a high spec radio.

Then I came across a nice review of Turnigy 9X radios and how they can be upgraded to a much more flexible system and also software. The original firmware of 9X radios is a bit cumbersome to use. Rather illogical menu system and some limitations. The receiver is huge and heavy for a foamy plane (18 grams). However it is possible to modify it with some cheap items. The result is a very capable radio unit that still has an exceptionally low price.

With FrSky DIY kit you can actually convert your 9X radio to FrSky protocol. A more robust protocol with great range and features.

With a clever little programming card called SmartieParts 9X it is possible to reflash the radio to er9x firmware even.

This will enable unlimited swith mapping. Anything can be assigned to any switch on the radio. Also it extends model memory to 16 planes (originally 8 memories). And with er9x software you get a more logical menu system.

To be able to fly my Easystar with FrSky radio protocol I need to retrofit it with a compatible receiver. So I purchased a receiver with telemetry. A nice feature, I could for instance see the battery voltage while flying. As I understand I can set a warning even for low voltage. Will check how this works.

For the indoor plane I bought a small 5-channel receiver. It weighs only 2 grams (!!!)

5-channel

This unit is so small that I will need to solder micro servo connectors onto the servos.

To really upgrade my radio I also bought a LiFe battery specially made for transmitters.

Transmitter battery pack

This battery will replace the current array of 8 AA cells. Charging 8 pieces of Ni-Mh AA batteries takes ages and they are hard to maintain on the long run. A TX battery on LiFe will give true voltage reading for the radio and it provides 10V against LiPo batteries which would overdrive the radio circuit board.

I will have a major upgrade when everything will be ready. First I need to get hold of the packages. Chinese celebrations mean that hobby parts are delayed. Now the celebrations are already over, so hopefully next week my package will get posted and travel to Sweden from Hong Kong. Exciting it is.

Weather is turning into Autumn, so indoor flight season is soon to be started. As I understand from 1st of November we can fly again at the school sports hall. Not much time left to build my plane.

With best regards,

Sir Crash a Lot

Hello,

I need to start with an apology, my blog activity was plumeting to new depth since my last post. As you can see the title I try to summarize what happened since February.

Last time I talked about the Ladybird quadcopter. I did a maiden and several fun flights with it since. It is a bliss to fly when weather is not allowing outdoor flights. You can fly it in the flat easily. I checked whether the propellers can be any harm. They aren’t, I tested them on my own palm, it doesn’t hurt the skin. My cats are very keen on catching the copter, but I keep it a bit off of their proximity. As I know that the prop cannot hurt them it is more like a precaution for the sake of the small copter. No animals were hurt during the making of this clip:

The 16th flight of my Easystar. Some Ringebu RC style landing even:

17th Easystar flight:

18th Easystar flight:

19th Easystar flight:

20th Easystar flight:

21th Easystar flight:

↔

I am getting more and more used to the Easystar and fly it faster and lower. So far I had some hairy moments in combination with wind gusts, but did not crash it yet. I think that I am getting more and more interested in extending my flights to other models as well. Easystar is a great plane to begin with, it can show you many different flight types. It can glide, it can do loops. It can fly rather fast. It is easy to land and it has a forgiving character. Maybe this latter is its biggest weakness after all, as it lacks “the thrill” when you are getting used to it.

I will keep my Easystar, since I really like it. A great allrounder plane with high fun factor. But I will purchase some other models soon. Which ones? I will tell in my coming post.

With best regards,

Sir Crash a Lot

Hello,

I wasn’t flying too much during this year, had some issues of private matter that took my energy from flying.

Now I am back, trying to catch up. It seems that part of my club is already flying multicopters at an advanced level. And there are also some news about our flying field. Unfortunately bad news, the local council is taking it away from us, we are no longer welcome there from 1st of January 2013. So rather interesting flow of events.

The multicopter issue is worth covering in more detail. I am learning the important notions about multicopter flight, will try to get more advanced in this matter during the Spring. I plan to build one beginner model actually, that will teach me the basics.

The flying field issue is more complicated. There is a motocross track in the vicinity, it is quite loud and dirty. But hey, dirt biking is so. Anyhow the council wants to move them and also us. First they did not give anything in return, then the club protested. Now they consider to offer another field somewhere close to the city. It is not so easy to just pick an empty land. We have to process the land, make it smooth, plant quality grass, cultivate it to be smooth and also transport our tools and containers there. And build up the fences, the benches and the basic club facilities. So a huge piece of work that the council does not want to help with. Very awkward way of handling this issue.

Update. End of 2012 we received some great news, we can stay on our flying field for some time. The council changed its mind.

My 12th flight from week 17 you can look at here:

My 13th flight is also recorded:

I just had my 14th flight with the Easystar, please find the video here:

During my summer holiday we were taking care of the house of our friends. They live in the countryside, close to a lake in the forest. Very nice location, calm and peaceful. I could not resist to explore their garden with my Lama v3 helicopter. So I did. I came up with some challenges that I pursued. Some hovering, then some flying around the garden. Also some precision landing on our car.

Then my fantasy got cranked up and I came up with even more exciting plans. Why not try to fly through the car? I mean, how hard can it be? 🙂

And while I am at it. While not fly into the baggage compartment, land there? Then take off from the baggage compartment and land outside the car? It is really that hard? 🙂

During the winter I had very few flights. Two of them were recorded, these were indoor flights in Mölndal school sports hall.

I am getting more flights now. This Spring I am stepping up from the Lama v3 and will start with multicopter action. On last flight 13w07 I crashed the Lama and I do not intend to repair it any more. I had a lot of practice on it, it helped with orientation skills. Hovering nose-in and orienting at low speeds. However I am getting tired of the stupid limitations of Lama v3. It cannot fly beyond a lean angle, otherwise its control system just locks up and the heli gets in an unstoppable dive. It is very sensitive to wind and at the same time does not have the power to cope with it. Even its own turbulence disturbs the flight, so I am happy to consider it part of my past.

I am looking at a tiny multicopter called Ladybird. It is from Walkera. Helipal.com has a nice description to it, you can read it on their page.

There is a v1 version of the Ladybird. That has a much bigger radio controller with some programming possibility. And it has a 6-axis gyro system (gyro and accelerometer) instead of a 3-axis system (only gyro) of the v2. As I understand the v1 is slightly more stable, but the v2 is still very stable so if you are not looking for the nicer radio you might just as well like the v2.
Hobbyking has a detailed review of the v2 Ladybird, where they tell about the differences.

I have another project, will tell about it later.

Thank you,

Sir Crash a Lot

Hello,

Spring is here, the long winter sleep is over. I haven’t been flying for real for the entire winter, only did some simulator practice. So when time was ready to actually fly I was rather nervous.

To cure the lack of fingertip feel I launched the simulator to get some reflexes. Please find some hovering exercise with an Ultimate biplane.

I observed great interest in this plane, ArcticRC and his mate fly this model in the North of Norway. Great plane, great recording.

Nevertheless, I am still flying my modified Multiplex Easystar. I plan to learn flying more before I build a new model. Need to get more confidence in hand starting (although that it might not be needed with planned models), also handling wind gusts and of course flying more stable. I think the more practice I gather with current plane the more I can avoid some stupid mistake with future planes. Although that pilot error is never excluded, how much I might practice.

We had some promising weather during the week, so on Thuesday after working hours we drove to the field and started flying. Clouds around us were rather threatening, wind gusts came from nowhere, but overall conditions were okay.

I had some problem with one of my mini cameras, so I just have the hat cam and the Hobbyking Wing Camera recording. Anyhow it is more than enough material.

I managed to start and land without incidents, however once I did a full roll without willing to do it. I was subject to a stronger wind gust, the plane was tilted almost 90 degrees along longitudinal axis. I wanted to correct, but did not react fast enough and this let the plane do a full roll without me doing really much about it. I think I started to correct but was more amazed by the fact that my Easystar can fly “so advanced” than I was ready to act. Fortunately I was at altitude, so the plane did not lose height that it became dangerous. After this happening I was more alert and could correct wind gusts.

I did some low passes, also some gliding.

My conclusion is that this 3-blade propeller is not really god. It makes transportation much more difficult. The wings cannot be stucked close to the fuselage as you have a blade every 120 degree. With a conventional 2-blade this is no issue. The efficiency is lower, this results is loss of power. And for some reason even though that I have reasonable pitch on it the motor revs crazy high. So I did not dare to use it on full throttle for long.

I ordered APC 6x4E pusher props, will mount one when I get them. That configuration worked much better, but I cracked that prop earlier. Hence the try with 3-blade.

Here is my 11th flight, please check it out.

With best regards,

Sir Crash a Lot

Hello!

I had some flying at last! This winter wasn’t really rich in flying. I haven’t got any plane that can be flown indoors, although I started to practice at least in simulator. I received a car as a present from my mother-in-law, now it is registered in Sweden, so I can drive it. This makes transportation to the flying field much-much easier. Carrying my plane on public transport was always a mess, people stare at you and you have to be extra careful to not break the model on the bus/tramway. Every grab handle or door is hazardous for the integrity of the airplane.

I took my Lama v3 to the club, Friday night we met at Mölndal in the sports hall of a school. The others had various slowflyers and multicopters even.

My flying skills got rather rusty (or dusty?), so I took caution. Practiced some rounds and 8 figures. Had to be careful to not fly too high, since the others were flying airplanes there. Was fun after all.

I wanted to spice up my recording, so had my hat cam and a mini camera on Lama even. The mini camera influenced flight characteristics of Lama, it became nose-heavy. So I had to fight with cyclic to maintain constant speed. If I sped up Lama lost control and dived into the floor. Lama cannot fly fast at all.

I have seen a clip on Youtube that explains how much difference it makes to have the music of Inception in a clip.

 

 

So I just put Inception music into my clip, the effect is dramatic 🙂

 

 

You can even see another recording from a club member. At 3:12 you can see me with hat cam and full concentration on the face. Quite amazing to see myself flying, now I understand why the others laugh at me when I have my hat cam on 🙂

 

 

With best regards,

Sir Crash a Lot

Easystar 10th w1142

Hello,
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I had my 10th flight with Easystar, a nice number it is.
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This time we flew in really strong wind. I flew in constant steady wind at the sea, that is not easy but you can manage after that you get familiar with wind direction and strength. But same theory did not apply on Sunday. There was a steady wind of 6 m/s most of the time. But every now and then the wind just died to almost calm state, then we got some really strong gusts of up to 13 m/s speed. That was the challenge. Upon start and landing I had major difficulties, I am not at all comfortable with such strong wind. I did not crash the plane, but I had to fight for it several times.
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Prior to flying I changed propeller. I had a 6x4e pusher on, some cheap propeller from Hobbycity. It was not really well balanced from start and then I cracked it when one of my early start attempt ended up in a very low pass over the vegetation. It was so low that I actually flew straight across some tougher grass and the prop acted as a chopper for some brief time. This cracked the last half centimeter on one blade, so it wasn’t really healthy.
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I thought that I will be smart enough to try a 6x3e pusher prop. How hard can it be? It did not really work out. For some reason thrust is very low. It pushed the air backwards but just. Maybe I put it up in wrong direction, I have to check this more. Anyhow, right now I have maybe 2/3 of thrust at maximum. Maybe less. Starting the plane and flying it in that much wind was a major challenge. At some point I thought that wind is pushing it more backwards than I can get forwards. Since it was very turbulent I had difficulties flying straight, it was all over the place.
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Landings were extra tricky. When descending a sudden gust can take away altitude at alarming rates. A quick descent of 3-4 meters is likely. At low height this can mean plane in the lake for instance. So I was very careful above the lake. But no matter how careful you are, some unexpected event can happen easily with such wind speeds. Once I landed already, Easystar was skidding on the grass and slowing down. Suddenly a stronger wind gust liftet up the plane from the ground, since it was strong enough to temporarly simulate much higher speed of air flow around the wings. So even though that the plane was already landed it just took off.
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Another risky event happened at one of my starts. I am plainly rubbish at hand starting the plane, not much to sugar myself about it. Normally you should throw the plane into the wind. So you get more lift at low speed. Now I had reduced thrust on the propeller, my skills are slowly improving (but still being rubbish) and I had tricky wind conditions. I wanted to start, the wind just dropped, I had no good thrust to pull me out of trouble and I probably even threw it badly. So the plane just ricochet from the grass and then it could take off when the next wind gust helped it. A really chaotic takeoff it was. HaBoRC put some funny comment from the depot as you may hear 🙂
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I managed to try out my brand new 35 USD camera, that went without issues. Works like a bliss. In my video you can see the difference. I have a standard definition keyfob camera on the nose of the plane. It has a 180-degrees fisheye converter lens mounted. The Wing Camera from Hobbycity is a stock item, it comes with a nice wide-angle lens from the store as stock. So ready to use. If I count the price of SD keyfob + the fisheye converter I am already above the price of the HD Wing Camera, so choosing the former is just silly. The latter is much better value. You may see a comparison chart in my post from the other day.
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The footage I got with the new camera is simply amazing for me, now I can see much more detail. If I manage to fly this kit on a calm day the turbulence will not influence so much, so I can get really nice footage. Looking forward for some nice sunny and calm autumn day.
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There is one issue with HD resolution. The computer power you require for it is extreme. I have an old computer that was put together by no other than my humble self. This act of brave assembly happened late 2005, I bought some proven components that were already free of childhood inperfections. So I went for stability instead of power. I used following base components:
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– AMD A64 2200+ CPU
– Asus A8N-E motherboard, on Socket 939
– 1 gig of DDR-I ram
ATI X800GTO2 graphical card (a variant of X800XL) with 256 megs or VRAM.
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This was quite okay up to the time when HD appeared. On SD resolution it handles all tasks except gaming. But I don’t do gaming anymore. With HD it becomes a different story. HD videos don’t play on my computer without judder. Even 720p (1280×720) resolution drops frames while the computer struggles on 100% power. 1080p (or 1920×1080) is not even worth trying. It is just some frames every 10 seconds maybe. Hopeless.
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It is important to make some difference between playing an HD footage or processing it. Playing can be helped by some more modern graphical card that can take over computing. So even a low-end computer can handle playing it. But processing in a video processing utility is a different story. For that you need high power from the CPU, a lot of RAM and good data transfer on the motherboard. In short you need a modern computer.
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I made the editing anyhow and had a lot of waiting. When trying to align two video tracks for a picture-in-picture layout I am checking on the preview pane if the two frames are in roughly aligned. It is no professional work, if it plays within a half second I consider it already a pass. On SD footage this operation was already difficult, since my computer is low on performace. There were a lot of dropped frames, you had to sort of “lead” the cursor, move it and wait for the result before you let lose of the mouse button. With HD this is much worse. It takes several seconds for the preview pane to update. A simple play operation is meaningless, it takes seconds without picture update, then you pop up somewhere else on the timeline. Totally useless. The only way to work with it is to move the cursos very slowly and then wait for the result. I fought with it for 2 hours to get 4 pieces of picture-in-picture shots aligned. Very time consuming.
Rendering itself was surprisingly fast, despite HD clips the 8 minutes footage rendered in roughly 1 hour. Not so bad. I render still 640×480 resolution, maybe should try 720p rendering next time. I don’t know if there is so much to win about it in my case.
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What I would need is much more computing power. I read a lot of reviews and came to the conclusion that it is time to buy something that will last for some years in the future. Maybe not 6 years, we shall see how long I manage this time.
I set my eyes on the Core i7 architecture from Intel. It has 4 cores and all 4 can simulate 2, so alltogether you get 8 virtual cores. Despite being “only” quadcore it beats the respective offering from AMD by a good margin in video processing. In some test under Sony Vegas 9 it was almost 2x faster in rendering (compared to a 6 core Phenom II processor). So that is the aim, to have a really powerful CPU. I will target a lot of RAM even. Minimum is 4 gigabytes, but can extend later depending on needs. Considering the graphical card I don’t really have high demands. My favourit RC simulator shall run without glitch, that is the specification. I made some studies regarding this issue, checked homepage of the simulator and checked their recommendations. Also checked some Nightflyyer reviews about specs.
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We shall see how I manage. When I will get the new system running and I tested it I will try to get some comparison.
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Update 2011-10-30
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I tried out my 3-blade propeller. It is a Master Airscrew, 6×4 pusher. MA0640TP is the type of it.
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As a subjective feeling it gives more thrust than the 6×3 I had on during the last flight. I look forward to test it in real life. Made a short test video of it. Looks nice when the tail control surfaces get aerodynamically active at half throttle. Haven’t revved it over 2/3 throttle, it is quite loud in the living room 🙂
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Best regards,
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Sir Crash a Lot

Hello,

I purchased a shiny new Hobbyking HD Wing Camera recently. Did test it but haven’t wrote a post yet. Now it is high time then.

This camera is slightly bigger than the simple keyfob camera. To summarize the parameters I can write a small comparison for you. HD camera first, SD keyfob second.

Resolution: 5 megapixel vs 0.3

Video resolution: 1280×720 vs 640×480

Memory card needed: Class 10 MicroSDHC (on both)

Price: 35 USD vs 15

Weight: 30 gram vs 15

Wide-angle lens: YES vs NO

Battery life: 2 hours vs 3/4

If you compare the two it is a no-brainer actually. To have decent wide-angle you have to get a converter for the keyfob camera. That jacks up the price to same level as the HD Wing Camera. And then image quality just decides on favor of the HD camera.

Using this camera is very easy. You can find the manual on Hobbycity homepage or just Google on RD32 camera. It is some sort of action camera, that is waterproof and you can mount it on your bike or cross buggy. Or whatever extreme sport you might do.

Appearently this is the same board, but no waterproof shell. Only the circuit board and some shrink wrap around. Hence the price. It is no GoPro, but does not cost 220 USD either.

I made some very simple comparison test. Had the old SD camera and the new HD camera in my hand and tried to pan them around.

I will need to try it out in flight as well. With some tweaks it can be used as FPV camera. Can record and broadcast same time. So quite a versatile unit.

Best regards,

Sir Crash a Lot

 

Hello,

I have two keyfob cameras from Hobbycity, the old SD resolution ones. Their code is #7, the worst of the lot actually. #3 was far better.

These cameras have a built-in battery, that is a 1-cell Li-Po with 140 mAh capacity. You charge it from USB-port. As far as I know traditional USB ports supply maximum 500 mA current. So this would charge up in roughly 17 minutes. I am very unsure how good the battery charging circuitry is in the unit. I would assume not so good. The premature death of my battery underlined this thought.

I was reluctant to just dispose the unit. It costs 15 USD, so quite cheap. But why dispose something if there is a chance of mending it. So I tried.

The idea was to buy a small Li-Po battery (done), and some JST connectors. So that I could remove the small battery, solder on the JST female connector and then use the external battery with some adhesive velcro tape. Brilliant 🙂

I tried to solder the contacts onto the wires. These wires are very thin, so use a fine grade soldering iron. Mine is very coarse, had to be very cautious.

When you have soldered the wire onto the metal pin you have to push together the last portion that forms an open U-shape. Otherwise it will not enter the plastic connector housing.

Then I had to remove some material from the other half of the housing. To have a good support for the connector I removed a rectangular area.

The connector fits nicely.

I double checked the polarity to be sure. Then I could assemble it and glue in the connector. It will be subject to some force when connecting and removing the outside battery. I used CA glue.

Just a size comparison, the new battery next to the camera unit. I will use adhesive velcro to fix it on top.

Maybe I will have the battery on the plane and the camera will sit on the battery. This way I will get better (less) drag coefficient. Important in flight.

I will need to do this on my other camera, that has reduced battery life. Probably will throw in the towel soon. Since this new battery is 240 mAh (vs 140 for the original) I will get significantly better battery life. And I can monitor the cell voltage with my Cell Voltage Monitor device. Important factor in keeping batteries healthy.

Best regards,

Sir Crash a Lot

Hello,

I would like to write a post about how to assemble Hobbyking Magnetic Prop Balancer device. It might look easy on the picture, but when you get to it you might find this helpful. Since no instruction manual is shipped, like in case of an IKEA furniture you need good assembly skills.

You will need to align the two sheets that have trapezoid shape and connect them with the U-shaped ones. Something like this.

For assembly you will need to slide the metal inserts and bolt them on with the small diameter screws. Please observe that only one side of the inserts is threaded, so you need to insert the screw from the mating side. This way you will have clamping force.

Then you will need to do so on the other side as well. You might need to peel off the protective paper layer. Depends on how tight the metal inserts are.

After this you can insert the big metal cup on one side. Secure it with the larger diameter screws.

One side is open, the other side is like a sunken cup. Into the open one you can insert the matching big cup. It is threaded, allows adjustment.

With the threaded cup:

Then comes assembly of panels.

Now comes the difficult part. You have to tear apart the 2 magnets. They are really strong. Do it carefully. When they are apart you can insert them into the cup features on both sides.

Between the two magnets should the axle float. The axle is pointy at the ends, so friction will be minimal.

Onto the axle you can slide the 2 conical rubber features. This will support the prop.

If I am right the rubber O-ring can sit on the adjustable side of the balancer.

When ready it looks like this.

A short video of how it does work.

Best regards,

Sir Crash a Lot