Thrust stand V2

Having spoken with a few folks on RCGroups I rebuilt the thrust stand to get some more accurate results!

My first iteration did not have an equal distance from the scale measurement point to the motor center point.  This version does.  It also moves on a real hinge to reduce movement friction and is a bit further from the ground to reduce ground effects.

YKS MX2204 2300KV brushless motor review

I received two YKS MX2204 2300KV brushless motors for reviewing purposes.  Needless to say that receiving them for free will not change my review.  This will be my first motor review and I'm excited to dive into it!  Being my first I don't have much to compare them to besides some Le Todar 2204 2300kv motors I'll also be reviewing and the Cobra 2204 1960kv motors I typically fly.

Specifications:
Model: MX2204
KV: 2300
Motor diameter: 27mm
Motor length (no shaft): 27.7
Stator diameter: 22mm
Stator length: 4mm
Shaft: 4.94mm
Weight: 21g
Batteries: 2-3 cells
No-load current: 0.6A
Top Mounting Holes: None

As with many brushless motors this size these are rated for 2-3s but since I fly 4s that's what I'll test them on.

DIY thrust stand

Being cheap I opted to make a DIY thrust stand out of some spare wood, a carbon fiber Nighthawk arm, and a hobbyking 30a ubec I had laying around.  Hopefully my wife doesn't mind me using our kitchen scale!  To show power usage I have an Electrify Powermatch power meter.

At a later time I'll be switching the hobbyking 30a ubec out for a littlebee 20a that I have on the way and eventually a Xrotor 20a or 40a.  I'm doing this based on results provided on miniquadtestbench.com (http://www.miniquadtestbench.com/cobra-2300kv-hqprop-5x4-gf.html).  A big thank you to Ryan for creating that testing site and posting his findings.

I would also like to test the difference between the stock hobbyking 30a and the same esc with the latest blheli flashed on it.

Here is my test bed for future motor reviews and thrust tests.

EDIT: 12-11-2015
     I tested the stand yesterday with some readings that didn't seem accurate.  I wasn't thinking about the leverage effect and failed to make sure the distance from the center of my motor to the pivot point is the same as the pivot point to where the arm meets the scale.  I also see that in order to do that I need one single point of contact on the scale and not a giant block.  I'll be fixing these issues tonight and testing it again.

EDIT: 12-30-2015
     New stand!


Version 1: Needs tweaking!

Inexpensive 210mm build part list

I wanted another quad for testing and as a backup.  I'm on a very limited budget so I thought I could build a new quad out of very inexpensive parts (mostly acquired from banggood).  Here is a list of items and I'll post the build log whenever the parts get here.

The total (minus the extra esc) comes to around $190.  I paid $10 for a used PZ0420 on RcGroups and $5 for a cloverleaf antenna.

The entire build cost just above $200.  I already have batteries so they are not included in the cost.  After adding it all up and thinking about the work I have to do it makes me wonder if I would have been better off buying a Plug and Fly used Tweaker (or similar) on RcGroups as I've seen them go for between $175 and $225

FPV goggles: Fatshark attitude v2 vs Quanum v2

If you've read how I got into the hobby you've heard of my failed attempt at getting into FPV.  Since that time I've had the opportunity to do it right and here is what I've found.

I couldn't find anyone around my area that flew FPV and therefore couldn't try out goggles.  I attempted the local hobby shop and they had a pair but it wasn't for testing purposes.  I finally dove in without testing.  I started with a HobbyKing Quanum V2 kit and flew with it for a few weeks before getting lucky with an amazing deal on some used Attitude V2s.  I'll outline some pros and cons of both setups and a simple comparison paragraph.

How to flash Betaflight on a CC3D

Updating betaflight with a CC3D can be stressful if you don't take the proper steps.  Here are the steps I take to do it successfully.

EDIT: (2-15-2016) - I believe Cleanflight firmware stopped supporting flashing from Open Pilot.  You can still do it with betaflight CC3D_OPBL but I recommend checking out http://www.southquay3d.com/index.php?route=news/article&news_id=9 for a more permanent solution.

EDIT 2 : (4-14-2015) - Since using the non-OPBL way to flash my CC3d I have not been able to flash anything else even attempting to connect to it with my FTDI adapter.  I found it easy the first time but haven't been successful since.  Because of this I recommend sticking with betaflight C3D_OPBL and even though it's a painful process it's not all that bad.

1) Open OpenPilot GCS
2) Plug USB cable into CC3D but NOT the computer
3) Click the Firmware Tab in OpenPilot
4) Click Upgrade & Erase
5) It will ask you to plug in your board so do so.
6) It will upgrade and erase then connect and start the flight time counter.
7) Click Rescue
8) Disconnect and reconnect USB
9) Click open and browse to betaflight_CC3D.bin on your local machine.
10) Check I know what I'm doing and click Flash.  It will go pretty quick and you'll see blue led on your CC3D blinking.  After it's done wait 20 or so seconds.
11) Disconnect USB
12) Open Cleanflight configurator
13) Plug in Battery
14) Plug in USB after the beeps
15) Cleanflight should pick up the com port.  Click connect

All done!  Change some settings!

Whenever you click save and reboot it will disconnect from Cleanflight config.  Just wait a few seconds, disconnect the usb, and reconnect.  Sometimes I have to close cleanflight and open it again for a proper connection (With the newest configurator it seems like I hvae to do this more often).  Other times I have to disconnect the battery and usb then reconnect.

Download betaflight from https://github.com/borisbstyle/betaflight
The cleanflight configurator is a chrome extension so add it through chrome.

Mini quad 101 - What is all this stuff?

First I want to express that all this is my opinion.  I'm not surveying a sample of the population to determine "the communities" view on things.

Why mini quads?
When I got into the hobby about 2 years ago multiwii boards were pretty common but the functionality was flaky.  Naze32 was new on the scene and I didn't have one or know what it was capable of.  Most people were flying larger (400mm typically measured diagonally from motor center to motor center) size multirotors using MutliWii, APM, Pixhawk, or something similar.

I'm not sure who started it but smaller (250mm size quadcopters) started hitting the scene.  These were smaller, faster, and more nimble than their larger counterparts.  These, with the addition of first person view (FPV), allowed for some pretty intense flying.  Racing and acrobatic flight pushed building these smaller, faster, and lighter.  It pushed development of flight controllers, speed controllers (escs), motors, and associated firmware.  Everyone started coming out with lightweight and strong carbon fiber frames.

As of this time I think mini quad racing is still on the rise.  Companies, and individuals, are still releasing new frames in sizes ranging from 130mm to 280mm, faster escs, different props, motors, cameras, video transmitters (vtx), and everything else that can go on a mini.  People are pushing the boundaries of what their setups can do and software engineers are constantly updating firmware to push the limits of the electronics.  There is lots of competition and advancement.  It's great!

Mini quad parts
FC (Flight controller) - I'm starting here because it's a very important part of your build.  Even though these are pretty interchangeable you'll get some advantages using one over another.  As of right now they come in only a few different varieties, and many clones.
I would say Naze32 and CC3D are the most widely used at this moment but there are lots to chose from.  Instead of getting into it I'm going to link another site. http://blog.oscarliang.net/best-flight-controller-quad-hex-copter/

Frame - There are many more varieties of frame and in my very limited experience they are all very similar.  Most are carbon fiber (varying quality) with different plate and arm thickness as well as layout.  Some are larger allowing for bigger props.  Some are made to be light, some extra durable, some specifically for a gopro and fpv, then others for line of sight acrobatics.

Motors - These  don't vary nearly as much as frame and I don't yet have experience with a lot of different choices.  I will say that cobra 2204s 2300kv are leading the charge and recommended and flown by many pros.  I've been running cobra 2204 1960kv on mine for a few months and they have seen lots of beating and still run smooth as silk.  I've only used 2204 because my experience has been with a 250 class quad.  If you're running a 150mm frame you will probably want smaller motors, but maybe not!

ESC (electronic speed controller) - Again a huge variety but current winners are kiss and littlebees.  Most of the new varieties run BLHeli with a SimonK or BLHeli bootlader.  They come in BEC and OPTO configurations.  I tend to run opto (no bec on board) and power my FC in another way.

PDB (Power distribution board) - Many different makes and models and choosing one depends on your frame of choice and power needs.  For example, my FC needs 5v and my camera gear needs 12v.  I could run anything that fits my frame and provides these options.  Some of the PDBs out there incorporate both 5v, 12v, and an on screen display (PowerOSD Pro).  That's a really nice choice for a really small or clean build.

Battery - You'll most likely be flying either 3s or 4s, though I've seen some 6s use.  I recommend going straight to 4s.  I don't recall offhand but you'll generally see a 30% increase in power when moving up one cell.  Most commonly in 250 size quads you'll see folks flying 1300mah to 1800mah.  The smaller your quad the smaller the battery.

Props - For 250 size quads you'll be using 5" or 6" with pitch varying between 3 and 4.5.  For smaller quads you'll get into 4" blades.  3 blade props produce more power but lose efficiency.  Both OscarLiang.net and RCModelReviews provide good benchmarks to follow.

Camera - Huge variety but the current leading camera is the HS1177 (PZ0420 chip).  These come in standard and the micro version.  Many of the smaller quads can only use the micro version so check your frame!

vTX (Video transmitter) - I use the Skyzone TS5823 because it's light and cheap.  I see a lot of folks using immersion as well.  For racing most people tend to stick with 200mw.

Antenna - The only real option for FPV is a circular polarized antenna.  Lookup IBCrazy and all the wonderful things he has done for the hobby!

Video recording - If you have money you'll most likely be using a go pro.  If you're like me and have less of that than a Xiaomi Yi, mobius, or runcam is just fine.

FPV Goggles - If you're racing you'll want some goggles.  There are pretty much two types to chose from: Goggles (fatshark and skyzone) or box (Quanum or Headplay).  There are others but those are the main.  I have both goggles (Fatshark Attitude V2) and a box (HobbyKing Quanum V2) so I'll be doing a thorough review in the next week.

I'll be getting into all of these in further detail with future posts.

How I got back into quads

I'm finally going to start getting to the mini quad stuff!  My one and only quad is flying wonderfully (besides a weird yaw issue).  My FPV setup is working nicely. My new Xiaomi Yi is on the way!  I'll soon be able to really analyze my PID settings and start posting videos.  Here is my current setup.

 

How did I get back into multirotors?  It was a really lucky purchase on RCGroups.  Someone offloaded a drone package for a really good price.  I purchased it, did a bit of work, and sold everything but something to get me started.  It was a somewhat working Nighthawk 280 with emax 2204 motors, emax 12amp escs, a cc3d, sony 700tvl camera, skyzone ts5823 vtx, and a few 1500mah 3s lipos.

I flew it a few times line of sight but I really wanted FPV so I purchased a Quanum V2 setup from HobbyKing and off I went!  On my 10th or so flight (Angle mode) when I was doing a quick turn it started flipping and fell out of the sky!  After lots of research I saw that it was most likely motor/esc syncing issues.  I flashed blheli on the escs (these don't support damped light and I don't recall if they support oneshot) and started testing all of my motors.  After endless configuration settings I decided to purchase all new cobra 2204 1960kv motors and SN20 ESCs.  I haven't looked back since!

Here are some of the mistakes I made while going through all this:

Pay attention to your battery C rating!  When I had my new setup going I was still using the old 3s batteries and puffed them quick.  I had 3x 1500mah 25c batteries that were capable of 37.5 amps (1.5ah x 25) and 2x 1500mah 35c (1.5ah x 35) batteries that were capable of 52.5 amps.  According to the rotorgeeks website for my motor (http://rotorgeeks.com/index.php?route=product/product&product_id=77) the 5x4x3 triple blade props I was running on 3s were pulling around 11.7amps per motor or almost 48 amps!  No wonder I puffed those 25c batteries.

Flashing madness!  I run BetaFlight (Boris Github repository - https://github.com/borisbstyle/betaflight) on my cc3d and that project is updated very frequently.  I could flash new firmware every week if I was up for it.  First off, flashing the cc3d is a pain.  Every time I want to flash new firmware I first open up openpilot, recover it and flash the default firmware, then flash the newest version of betaflight.  After that I can open up the Cleanflight app again and get to work.  One note with cc3d.  You MUST plug in your lipo before connecting the board to your computer!

Build as clean as you can.  I haven't had the opportunity to use one of the all in one power distribution boards (PDBs) so I have wires running everywhere.  If I have a little glitch in my video feed it can sometimes take awhile to find what wire is coming loose.  Even if you have all your connections hot glued or use thick ca they can still come lose!

Getting into fixed wings

Yesterday I posted about getting started in RC and here I'll continue with my fixed with hiatus.  It all started out when I joined a local RC club (Natchez Trace Bandits).  When I joined we had a mandatory fixed wing training program.  Once you passed your flying test you could fly whenever you want but until then you had to fly with another member.  This group consists of mostly fixed wing nitro flyers that have been doing things a certain way for 30+ years.  I say mostly because we have a few multirotor fanatics but no FPV (besides me).  The club offers the use of two nitro trainers in a buddy box setup.  Since I had been flying Flitetest planes for a few months I felt comfortable without the buddy box and wanted to get my own machine up and flying.

My initial trainer setup was a Flitetest Storch which is a wonderful flying machine.  However, this plane is almost too easy to fly.  When I compared this to the big balsa nitro plane there was a huge difference.  The nitro plane was faster which meant landing was more difficult and heavier which made flying in wind a bit easier but also much less nimble.

I decided it was time for me to build my own large balsa trainer, but electric!  I purchased an ARF trainer from HobbyKing, a 46 size suppo brushless motor, and 100amp Turnigy Dlux from RCGroups and got to building.  Here is before

This is after.

That balsa trainer flew beautifully.  It could come in nice and slow and never drop a wing.  It was the easiest large (63") trainer I could ask for.  I fell in love with flying fixed wings.  From there I immediately wanted to push the limits and start getting into 3D.  Time to build a FT3D!  I had pretty decent success with that but easily damaged it attempting to fly too low and slow too soon.  I needed something that could take a beating and keep flying.  After lots of reading I decided to go with the Crack Yak by Twisted Hobbies!  I was in heaven.

Today the Yak still flies amazing even though it's probably composed of more glue than foam!  They recommended using welders glue, which is awesome but expensive.  I found that Dollar Tree thick Super Glue (CA) is almost identical to Welders and have been using that since.  I went all out with the Yak and got the landing gear.  If you fly in grass don't get the landing gear!  Most of the damage I had to fix was because of the landing gear catching in the grass.  Actually, even if you have a nice runway I don't see the point of the landing gear.  It looks cool but it's so much easier to simply land in a patch of grass or catch it.  I still have this plane today but don't fly it nearly as much.  It will definitely be one I keep on my wall.

I've had some issues learning what motor/prop combos produced enough power without a watt meter and thrust meter.  Ooops!  It went up so smoothly then tip stalled and wouldn't pull up.  Maybe there was too much weight in the nose and too little power.  This will have to be a winter project.

After practicing a lot with the Yak I gave this Great Planes Sukhoi a go.  It's nothing like the Yak and feels really under powered.  I wasn't terribly impressed.  It's been a pretty fun sport flyer though and has helped me get better at faster 2 wheel landing.

As of today I don't touch most of these planes anymore.  If I get a chance to fly it's all FPV mini quad madness.  I love it.

Lets get started

I've been in the RC game for a little over 2 years.  As soon as I saw FPV on flitetest I immediately fell in love with the idea.  I needed to try it!  I followed some instructions online, purchased all my parts, and started the build.  I wish I had started this sooner but figured now is better than never.  Here is a rough idea on how I started out.  I wanted to fly automated and at long distances.

First I needed a quad.  The one pictured below is actually v2.  V1 (fiberglass frame) met a very quick demise.  I had quite a steep learning curve.  It took flashing all sorts of firmware on the multiwii board to finally get the compass calibrated correctly.  Flight controllers have certainly come a long way.

I also needed some FPV gear.  I'm always on a very tight budget so I went the route of making my own Quanum like goggles.  Sadly the monitor I purchased blue screened so it made flying a little difficult.

Antennas!  I figured I would make my own 900mhz antennas.  That proved to be more difficult than I thought.  This antenna setup never worked past 30 feet.  The linear antenna was much better than my antennas but because of my blue screen monitor I still had issues.

By the time I got to this point I was pretty much over attempting to fly quads and FPV.  My setup was far from acceptable.  I had my quad in the air doing mostly simple line of sight flying and a little automated pathing but it was under powered.  After I flipped return to home and the quad fell out of the sky I decided it was time to get into fixed wings.  I sold most of my equipment and started building foam planes.  Don't worry, I get back into quads and hit it hard!