lørdag den 31. januar 2015

Turnigy Talon Carbon Frame motor mount modification

One of the major draw backs of the Talon frame is the Landing gear/ motor mount combination. Angled landings or light bumps cause the mount to shift its position, Even with very tight screws they still seemed to move. This meant trimming every time I took off. This was pretty annoying so I looked for a wat to modify the mount.

 The original mount, I moved further down the arm to make space for another option. I loosened them slightly just so that they can give way on hard landings.

Iordered 4x12mm motor mount off Ebay, there are sereval options available, both in Carbon, plastic and Alu. I opted for this as my other Alu mounts have coped quite well and withstand quite a lot of bad treatment. Link to the referred mounts.
The price was quite steep compared to CNC-Soloutions where i bought my other mounts $7.80 a piece, the plastic mounts are cheaper than these but i would reckon these would hold up longer.

Pretty light 7 grams pr. mount. The bottom clip is threaded in all three holes, so no need to have extra nuts to tie it down, the middle hole, can be used to stop the mount from rotating. Mine is just tightened for now, if it does not hold the mount, i might drill a 3mm hole through the arm and tighten the screw through this hole.

There are no screws when purchasing these mounts so you need at least 12 M3 bolts of at least 8mm in length if you don´t have any, well purchase a few off ebay, these are very handy and are used in many aspects of multirotor building. Bolts for the motor mounts

 I mounted the 12mm motor mount and simply tightened it down.
On the opposite side the middle hole is used to prevent the mount from moving, you need to drill a 3mm hole. I opted not to drill a hole yet, will first see how it behaves before drilling the frame.

 The mount holes do not seem to fit a standard motor, only two of the bolts can be mounted, the remaining two holes are a bit off center and would require a modification.

Well ready to mount, your motor and hopefully you have a bit more stability.

fredag den 23. januar 2015

SunnySky X2212 980KV

I have been hearing quite a lot of nice things about the SunnySky X series and when searching the internet and comparing the NTM 2826 that i have with the SunnySky's equivalent, the conclusion is that the standard bearings on the SunnySky are way better, more efficient and give an increased flight time. Here is just one such review. I figured that i ought to upgrade my motors and try these out. As you might know i like to buy a lot of stuff off Ebay and i am well aware of the fact that some of the quality is rubbish, brand products are often copied, sold at a cheaper price and the quality is nowhere near the original product. Most of the stuff i purchase is actually cheap and inexpensive stuff like, props, screws, tools, cabling and so on, so if the quality is bad, then what the heck. Expensive stuff like motors, ESC' s, flight controllers i will usually purchase at a more reliable source to have some assurance of the quality.

Upon searching Ebay for the SunnySky X2212 980Kv, a heap of motors came up, all claiming to be original, well at least they had the original photos of the motor, taken off SunnySky's web page. I searched the the internet for "fake X2212 980Kv" and found a few blogs where a discussion was going on about a load of fake SunnySky motors.

Link to RCgroup discussion on fake motors.

This made me forget my idea of ordering these off Ebay as apparently even well renown places like goodluckbuy.com and banggood.com were selling these fake motors. I decided that i would try to email a seller from ebay and asked him if his were genuine and made him aware of the fact that i knew there were counterfeits around and would demand a refund if i received a fake. He assured me that he did not sell fakes.

Ebay link to the SunnySky I purchased. (read the conclusion at the bottom of this page)

I don´t have the fake motor to compare with, so I did some research and then ordered one motor, just to be sure and if his product lived up to the specifications i could order the remaining at a later stage. The motor arrived after just a week and a half which was pretty fast.

Upon examining the box and comparing it to the data in RCgroups the box looked like a fake as they state that the original packaging is to the right, the outside wire is blue.
 On my package the outside wire is red, so i assumed that this was a fake.
But according to Sunnysky their packaging is done in heat sealed thick plastic and not in zip sealed thin plastic Note from Sunnysky mine came in a heat sealed bag. So this kind of gave me some hope, that it was in fact genuine.
The motor arrived in thick and neatly heated
plastic bags 
Fake  motors often come in thin zip tied plastic bags.

 One of the other things to look for is the heat shrink that tucks the wiring into the motor housing, this is nicely done and very clean, the heat shrink goes all the way through on the fake products the heat shrink is not very neat
The motor i received was very neat, the heat shrinks are tidy in all places.

Original is on the left, notice the poorly done heat shrink
The heat shrink on the bullet connectors is also well done with good looking and quality bullet connectors 
These are the bullet connectors on the motor i received.
This image is taken off the RCblog and shows the difference in quality the original is the right

 The bearings on the motor i received look original and measured  9.52 with a caliper

The fake one are a bit smaller.

 The windings should be neat and well made. They look very tidy and well done on the one i received.

 This RCblog photo shows the difference

 The font used also tells you of the originality, on some fake models you can see the different fonts used in the S, the motor i received has the correct font.
Other things look for

I then download the motor specifications from SunnySky´s webpage and simply measured all the parts and everything seems to be in order, so my guess is that this is the genuine product. The only difference i saw was the box. So this is either a very well made fake, or an original in new packaging.
But i can in no way confirm wether this is an original or just a well made fake. Either way, the motors perform well, so all the same, been using them for a while and they do run smooth. One of my blog readers finally found the evidence that proves these are fake, thanks to papadkostas for pointing it out, the web adress at the bottom has a small space between the sky, Kostas received a batch of three motors with one of them having defect bearings. So would not recommend this unless you are willing to take a risk. These seem to be very well made fakes.

torsdag den 15. januar 2015

Repairing my NTM Prop 28-26 drive motor

After building the Talon, i noticed the one motor vibrating quite a lot. I inspected the motor and came to realize that the top bearing was buggered. Rather than buying a new motor i set out to try repair it, and found out that i was quite easy.

To repair this motor your require 3 things, a C-clip 3mm, you can reuse the old one, but they are small and tend to disappear when remounting or disassembling the motor. I purchased a set of 100 off ebay for just over $4.

3mm Retaining Ring / Snap Ring / Circlip

You need at least the replacement bearing that is broken, but a good idea is to order both the top and bottom bearing for future purposes. I chose to try the more more cheaper bearings on ebay. You can find good quality bearings, but at a price that is some what half the price of purchasing a new motor

The top bearing is a 3 x 7 x3 mm that cost $5,85 for 10
10PCS 683zz 3*7*3 3x7x3mm Metal Shielded Metal Ball Bearings

The bottom bearing is a 3 x 8 x4 mm at the same price.
10PCS 693zz 3*8*4 3x8x4mm Metal Shielded Metal Ball Bearings

Shipping was around a week and a half for both the retaining ring and the bearings.
I simply removed the c-clip at the bottom of the motor, this enables you to take the motor apart.

The bearing as you see, was coming apart and needed replacing.

Using a screw driver i nudged the inner housing and the bearing out of the shell.

 Using small pliers i sort of loosen the outer shell by kind inserting the pliers between the outer housing and tried to force it up, the metal is pretty thin and weak, it eventually gave way and came out.

My bearing was shattered so i had to use a set of pliers to lever the remains of the outer casing of the bearing. If your bearing is still intact you could use a flat head screw driver through the opposite end to simply rest on the bearing and gently nudge it out. 
Inspect the motor around the magnets for loose ball bearings, they are quite small and stick to the magnets, remove them. 

Inspect the bell for loose ball bearings.

 Grab a 3 x 7 x 3 ball bearing for the top of the motor, put it in a plastic bag and submerge it in oil.
 Take the oiled bearing and insert it, press it hard to make sure it is sitting in place as far down as possible.

 Grab  a retaining ring and reinsert the bell on the motor, it should snap back on, so wath out your fingers don´t get caught.

 Inserting the retaining ring is a tricky affair, but i simply used my fingers to keep the one edge in place and my other fingers to push the clip in place...and viola....your motor is as good as new

torsdag den 1. januar 2015

Turnigy Talon Carbon Fiber Quadcopter Frame build

I decided to try out the option of using a power distribution board I had lying around, this mounts directly under the frame and tightened down with two plastic screws that I ten used to mount the flight controller.
Mounted the flight controller in X configuration. 
I soldered a wire from the 12volts for the voltage alarm on the KK2 board
Mounted the wire on the KK2 board, that gives me an alarm when the battery is getting close to depleted.
I later came to realize that the polarity was swiched around, the  + is on the right, closest to the edge of the board.
 Notice the + is on the right, not the left, I realized this when double checking my wiring. One thing to do is always run through all the cabling that you have soldered or changed. One simple mistake will give you white smoke and a bill for replacement parts.
I then soldered banana plugs on the ESC's + and - so I could connect them directly to the power board.
 Put some shrink tube on the wiring to avoid shorting.
 Connected the ESC's to the power distribution board.
Again remember to check your polarity, you can always use a multimeter to check out the voltage and the polarity before connecting the ESC' s  
 Zip tied the ESC's around the arm.
 Shortened the wiring on the other end of the ESC's, shrink wrapped it.
 Zip tied all the cabling along the arm. Put all three cables through a shrink tube, was not really necessary, but helps keep it neat and tidy.
 Soldered a XT60 plug on the cable that comes from the distribution board. Again remrmber to check your polarity, trust me been there, a mistake here is fatal for your rig.
 Forgot the power for the KK2 board, soldered a UBEC on to the 12 volts on the PDB
 Split the output of the UBEC, making two power sources, one for the KK2 board, the other for the Orange Rx radio receiver.
 Powered the KK2 board on pin 1 of the motor connectors, +5v is the middle rail and the - rail is on the bottom. The top rail is the signal from the motors.

 The other end of the UBEC I connected to Orange RX reciever. I plugged it into Batt/Bind, the middle is the 5v+ and the bottom is the negative. The top is not used.
 Plugged 3 pin servo cable into the throttle slot with only one wire attached in the top row for the signal.
This corresponds with pin 3 from the top of the KK2 board. The top is where the white arrow is.
The cables are mounted in the signal rail or the top row, that being the row closest to the middle.

 Pin two on the RX receiver Aileron corresponds with pin 1 on the KK2 board
Elevation on the Rx receiver corresponds with pin2 and rudder sits on pin 4 on the KK2 board 
Connected the aux channel on the Rx receiver to pin 5 on the KK2, this can if programmed on your radio, be used to control the selv levelling feature of the KK2 board.
 Zip tied the Rx receiver on the arm of the quadcopter.
I thought of an idea I wanted to see if works. The mounts of this frame don't look too rigid and I feared a crash will probably cause damage to my motors. I would prefer to use normal mounts but needed a way to customize them.
 I mounted all the alu mounts on the four arms all facing the same direction, the motors are off centre, but i reckon the result will be the same, the pull and thrust on the frame should be equal. Might require some offset adjustments.
Mounted the motors and zip tied the cable along the arm for a neat finish. 
 The quad weighs an astonishing 717 grams without the battery mounted, this will surely give me a good flight time.
 Mounted with a Zippy 4000 20c battery the weight crawls up to 1048 grams.
 Not done yet, we need to configure the KK2 board and mount the signal wiring from the motors
Check your cabling before plugging in your battey. Once checked plug in your battery. The KK2 should fire up. Using the 4 buttons at the bottom navigate down to "Load motor layout".
 Choose Quadcopter X mode.
 Yes you are sure.
 This gives you the motor layout. motor 1 signal goes to pin 1 on top of the power cable we previously plugged in the KK2 board. Motor 2 on pin 2 and so on. Remember the motor direction as well, jot it down on a small paper, you will need to alter it later on. If you don´t have paper you can always check the configuration using the KK2 board
 Exit back to the menu and move up in the menu to receiver test.
You should see your receiver settings. You need to trim your radio to get Aileron/Elevator/Rudder to 0, you can move the sticks on the radio and check if your setup is correct. If you move the throttle stick up, the corresponding throttle on the KK2 board moves up and so on.
Trim your radio using the Trim buttons to get the settings on the KK2 board to 0
 Once trimmed all settings should be Zero, you can also flip your switch that you programmed to check if it works.
 You need to calibrate your accelometer, navigate back to the main menu find ACC calibration.
Put your quad on a level surface. 
 System calibration taking place.
 All done
 Another options available on the KK2 board is the selv-level under mode
 You can if you have programmed your radio, use a switch to activate and deactivate self-level. Otherwise you can change this setting to always on. The KK2 board will power up with self-level on
 Other options include setting your battery alarm under the menu option misc. settings 1, mine is set to beep at 10.6 volts
 You can trim the battery if it displays the wrong value on the the on-screen display, this is done under misc settings 2.
 If in doubt, you can check if all the sensors are working correctly.
all good!!! 
There are a number of options like tuning the PIDs for better flight characteristics but will get into that later.
The finished product.
 The motor mounts all facing the same direction, and it does initially take off, but might need some offset trimming.

Well not bad for a couple of hours work. Time to fly....

Well after a couple of flights with this frame, I thought I would give my views on it. All in all the frame is very light and stabil frame, flying was very easy and due to the light weight it gave good flight times. It maneuvers nicely and quickly. 

Pros: The motor mounts tend to give way on landings, turning the motor just enough to unbalance it, this means that you have to center the motor once in a while when it starts to yaw. I tightened the bolt holding the mount, but did no good. I noticed that the mount is working its self into the carbon fiber tubing and slowly wearing it away. This will eventually become an issue as it will require a new tube. I have considered ordering a 12mm motor mount off ebay to use instead and moving the landing gear further inwards, loosening them a tad, so that they can give way if they endure a heavy landing, thus not wearing the tube.

After 4-5 flights without crashing the mount wears the carbon tube
My new plan is to move the landing gear further down the tube, loosen them a bit so they can give way and mount an extra 12mm alu motor mount at the end of the tube, this way the motor will be more stable.