Unseen and I chatted a little bit on this thread about good 4" quad.  I told him I had a Japalura on my bench and was planning a build.  I did mention that I would likely not post a build log, but after seeing his build log...I figure why not?

Poor planning for a build log meant I did not have the greatest photos of all the parts.  But I have plenty of photos of the progress.

Frame: Armatten Japalura 4" purple $77.50 USD
Motors: Armatten OOMPH 1407/3850 KV MOTOR $16 x 4 = $64
FC: CL Racing F4 with betaflight 3.2 $30
RX: Frsky XSR $15
VTX: TBS Unify Race HV $29
Cam: Runcam Swift 2 $40
Battery: Tattu 850mah $19
VTX antenna: DIY Pagoda $2 (I printed PCB and put these together)
MISC: Whitenoise VTX mounting plate $6, Bobbin FC soft mount $4, 1000uF Cap $1.50

This is me dry mounting the stack to see if everything will fit, even though I did solder wire together already







Close-Up of the Whitenoise board with VTX solder to it.




Underside of the FC.  In this photo, I have the XT60 connector going to side.  After I finished everything and mounted the battery, I think I am going to change it to the rear.  The prop leave little space for the connector to exist on the side.  Since I will top mount my battery, the side connector just isn't going to work.



All the ESCs soldered



Things pretty much finished






I made sure I have access to the bind button for RX.



So not quite completed yet.  Still need to mount RX antennas.  But before, I think I am going to reverse the Whitenoise board 180 degree.  I find the TBS Unify connect is more prone to damage when facing the front of the quad.  Also, I will switch the XT60 to the back, change VTX antenna to Pagoda (I can make it lighter and shorter...and I have 160 of them to use).  My TX is also current not working, so I haven't been able to test everything out.  I know motors all work through BF configurator.  Haven't checked the FPV portion yet.  Hopefully I can fix my TX soon so I can go fly.  Really excited to try a 4".

Nice build!

I was wondering what you needed 30A ESCs for - then I saw the propellers.

What kind of battery are you going to power this with? I fear you'll end up having to use something that's too heavy for the overall build to provide enough power for your power train.

I am planning to use Tattu 850 mah 75C. To be honest, I didn't realize how aggressive the props were when I bought them online.

30A is overkill, but this is the smallest blheli 32 ESCs I could find. I haven't checked the overall weight yet.

At least propellers can always be swapped.

With the simple 4045 two bladed props that I have on mine, it's almost too fast to be honest. I can't even imagine how much thrust you'll get with those monsters but I suspect you may be over-propping the motors.

My Tattu 850s finally turned up yesterday but I haven't had a chance to try them yet as despite being sold as having XT30 connectors, they arrived with XT60s, so I'll have to change them before I can use them. There's no point in the bulk of an XT60 on something this size in my opinion.

When I got the props, I knew they looked a little too much. I have a few set, no sense wasting them. I wanted something similar to my 5" cyclone props. You live and you learn.

I was also debating between XT60 or XT30. Most battery in this size had XT60 and easier to get, , so I just went with it.

It's got to be worth a try though, you might break the speed of sound!

Probably no speed record with my flying skills, but sure some high speed crashes.

Fixed everything I wanted to do.
Weight without battery: 225g
Weight with battery: 330g

Just 11g heavier than mine.

I hope your maiden flight goes well!

Thanks. Don't have a working TX currently. Trying to fix it right now on a different forum.

That's bad news. What's your radio?

Technically, it is not completely broken. But it is all in pieces while I am trying to fix it. It is a Turnigy 9XR Pro with a XJT module.

http://openrcforums.com/forum/viewtopic....062f6bcd73

That's a very strange problem you're trying to diagnose there, I wish you luck!

I have to say, that radio has looks that only a mother could love...

Yes, the radio looks is not going to win any beauty contest. Didn't your momma tells you that it is the inside that counts. When I started this hobby, I was clueless. On researching radios, the Taranis and the Turnigy came up as the two radios people were comparing. They both run OpenTX. When you look at the cost, Turnigy was only $60 and the Taranis was $200. So I went with the Turnigy. What a lot of people fails to realize, with the Turnigy, you need to buy a module and battery separately. This takes the price up to about $120-130. Which is still not bad.

The Turnigy has been great. A lot of good firmware support. Mike (ersky developer) is always improving the firmware. He is writing custom firmware to help figure out my problem. And he probably find this a challenge to troubleshoot my issue.

But it is probably time for me to start looking at a new radio. I know we briefly conversed on the new Horus X10S. I have been keeping my eyes on the RCgroups thread. There seems to be a big improvement over the X12. I am just waiting for one of the big whales to do a review before I take the plunge. In the meantime, I might put my radio back together, go out for a fly. It has been two weeks. The itch is getting harder to scratch.

It's an interesting point you raise.

Most of us, when starting out, end up looking at a bill that's more than we can bear if we were to buy the best radio and best FPV goggles. So we cut corners on these two 'buy once' items to keep the size of the startup bill below the pain threshold.

In the end though, your radio and your FPV goggles are the last things you should try to save money on. My first radio was a FlySky i6 - cheap and cheerful but it it needs more three position switches and channels. It's also limited to FlySky receivers which don't have the advantages of some other brands. My first goggles were Fatshark Predators, they're kind of OK, but the lack of an adjustable IPD made them a total pain to use as the fixed IPD doesn't match my eyes.

I now have a couple of Devo radios that I'm very happy with, but I miss being able to do the tricks that Betaflight and LUA scripting now lets people do with their Taranis radios. I got a pair of Skyzone SKY02S goggles which I'm really pleased with and the Predators are relegated to spectator goggles.

If I'd known what I know now when I started, I'd have bought a Taranis X9D and a pair of Fatshark HD3s and skipped the cheaper alternatives.