Califrag inspired Blackout Lowrider build log (MultiGP 3S Spec)

[mpbiv]

I didn't get to go to Drone Nationals, and quite honestly I would have been non-competitive at my skill level because I am still learning quite a bit. Ever since Drone Nationals I have been inspired to work on my skills and I am usually flying and/or building during most of my free time.

As I mentioned I have been building like crazy. I believe the last build thread I posted here was for my Blackout Mini-H quad: http://forum.flitetest.com/showthre...Quad-w-BrainFPV-build-log!&highlight=brainfpv

Since then I have converted my Twitchity Acro Quad to carry FPV gear for racing, I have also built a Flying Cinema Tankito30 Carbon, Two different different Tweaker180's (one with 1806's one with 2204's), and I currently have an Armattan Morphite V2 (with 5" arms) on the bench halfway built. That's not including the Impulse RC Alien 6" frame which should be here in a couple weeks. Between all these frames, the 2204 powered Tweaker gets the most flight time, followed by the Tankito, and the Twitchity Acro Quad.

The Blackout I have not flown in months! And that left me considering whether I should keep it since I've had the Alien 6" on pre-order and I knew it would be here soon.

So today the decision has been made to keep it, but I am going to rebuild it. This build is going to be heavily inspired by Califrag's lowrider build, which he flew to a 3rd place finish at Nationals. If you haven't seen his Blackout, here is the link to his blog post: http://forum.flitetest.com/entry.php?439-BOSMH-BlackOut-Super-Mini-H-Quad-Lowrider-Build-Log

This is going to be a full rebuild, I won't be using hardly any of the stuff from my original blackout build, except frame pieces.

The Goal: Build a Lowrider Blackout for MultiGP 3S Spec Racing.

Construction: the frame will be comprised of mostly stock Blackout Mini-H quad carbon plates, with the exception of the top plate being modded slightly to accommodate the fpv camera. Readily available hardware and standoffs will be used to complete the build, and some unique parts will be 3D printed to hold various components. I will make the 3D printed part files (.stl) available on thingiverse to anyone who wants to try their own build.

Electronic Specs:

• Flight Controller: SPRacing F3 Acro
• Motors: Cobra 2204 2300kv
• ESC's: FVT Little bee 20A w/BLHeli
• Battery: 1300mAh 3S (considering Tattu 75C)
• Props: HQ 5045 Bullnose
• FPV Cam: Sony 600TVL cased cam
• VTX: UBAD 200mW Race Band
• Antenna: VAS Airblade LHCP
• RC RX: some sort of Futaba S-BUS to keep wiring simple
• RC TX: Futaba 14SG (my defacto transmitter of choice for all builds)

STEP 1: Passing the point of no return!

Originally I was going to dremel the hole in the top plate, but after some thought I decided to let on of my buddies mill it out. It only took about 5mins to chuck it up on the mill and cut the hole, and it came out very cleanly. Make sure if you cut carbon to wear a mask and use a vacuum! Eye protection would probably also be a good idea.







I'll post up measurements of the hole and its position later. We pretty much just centered it and made it wide enough to clear the fpv camera bracket. Length wise it is just long enough to clean up the existing holes that were already in the top plate.

Thankfully, I believe this is the only irreversible modification to the Blackout frame pieces that I will need to make. Now that the hard part is over, onto hardware/nuts/bolts/standoffs next. I placed an order for these parts and I will update the thread when they get here with more details and pictures as I begin mocking up component placement. For the moment the plan is to space the top plate 15mm off the PDB, whereas the stock Blackout frame uses 35mm standoffs. This is a significant reduction in height and should bring the mass of the battery closer to the center of rotation for the frame.

Stay Tuned....

 

[C0d3M0nk3y]

Very cool.

 

[mpbiv]

So I got a little ahead of myself this weekend and in a rush to have a backup quad for race day, I went ahead and built "Version 1" of my Blackout Lowrider.

So there were a couple things I did differently than planned. First off I went ahead with the build using parts I already had, rather than waiting for my package of parts to get here. My order mainly consisted of 15mm standoffs and a set of the shorter Blackout arms for 5" props. My original Blackout build was with the arms for 6" props and you can kind of see that the 5" props clear each other and the frame quite a bit in the below pictures.



So you may be wondering, if I didn't receive my standoffs yet, how did I space out the two plates?

Well.......I took a look at the stock Blackout standoffs (which are 35mm tall black nylon), and noticed the holes go completely through but are not threaded to full depth. Checked my tool box and found a M3x.5 tap and decided to cut 4 standoffs in half (yielding 8 15mm tall standoffs) and then re-tap them all the way through. I did this using a dremel tool and some sand paper, while constantly checking the height using some digital calipers. Managed to get all 8 in the range of 14.94-14.99mm tall using sand paper to bring them to the final dim.



I had to design and print two pieces to make this build work. The lower block mounts the bracket for the FPV cam at an angle so that it just pops out the top plate. The top half provides a protective cage for the camera, and also holds the antenna tubes.

After looking at the finished quad for a little bit, I have lovingly named it "Shrek", because it's green, and the antenna coming off the sides kind of look like Shrek's ears.



Although I was inspired to attempt this build by Califrag's Lowrider Blackout, I have done several things differently. Not necessarily meant to be better, but really just to put my own spin/interpretation on building a lowrider blackout. One of the key differences you'll notice is that I have elected to keep the ESC's on the arms, which also allowed me to stuff everything else in the body of the quad without have two separate compartments.

Today my parts should be here, and I will probably keep using the cut down Blackout standoffs, however I will be switching out the arms for the shorter ones. I also have some green LED bars I would like to add, so this build will be on-going. As I go back through I plan to take more pictures and explain what has already been done to get to this point.

 

[califrag]

DUUUUUUUUDE!!!

This is so cool man! Great build!!! Wow the cuts came out PERFECT... I think I'm gonna have to send you my plates for milling in the future lol!!!

I think yours came out even shorter overall, I used 12mm standoffs but with my extra arm spacers is probably around 18mm of spacer.

The 3D parts you designed are really nice, I had to fandangle mine together from aquarium hose to make the top plate work out.

Wow I'm really happy to see this. I built up another lowrider but 5" and with 2300kv too.



Lookin forward to more updates

 

[C0d3M0nk3y]

As I go back through I plan to take more pictures and explain what has already been done to get to this point.

If you do go back and take pics, I'd like to see a couple things if possible.

1. The top plate removed showing the electronics.

2. How much of the camera is actually below the top plate.
​

 

[mpbiv]

If you do go back and take pics, I'd like to see a couple things if possible.

1. The top plate removed showing the electronics.

2. How much of the camera is actually below the top plate.
​

As promised, more detail!





These pictures hopefully answer your question. Could I go lower on the camera? Maybe, but I would probably have to get rid of the bracket that came with it, and most likely that would mean making a 3D printed holder that would fix the angle. One advantage to a fixed mount is that the camera angle won't move after a crash. But one of the reasons I want to use the bracket is because you can easily adjust the camera angle, and considering how the tracks are different every race, it might be easier to fly tighter technical tracks with less camera angle, or increase the angle for larger tracks where you are going to want to fly faster. At least that is my thought.

Ideally something that works similar to the camera angle on Soma's Alien would probably be the best. Maybe that is something I can work on later.







And here are what the guts look like. It actually wasn't that hard fitting everything in there.



Decided to remove the case to create a little more clearance for the camera to swivel.



Current weight without battery: 351g

Also in this picture the keen eye will notice I have switched out the arms for the shorter arms which bring the 5" props closer to the body, and turn the blackout into a 220 size quad as it was originally designed.

Keeping in mind MultiGP 3S spec class requires 300g minimum weight without battery: that means I can still try and shave roughly 50g off this. So I put in an order to fastener express for some aluminum hardware today, and when that gets here I will swap out all the steel hardware and re-weigh it. I can also shorten the ESC power leads now that I switched to the shorter arms. Not sure if those things combined will bring it down to 300g, but we will see.

 

[Spastickitten]

How much weight do you lose when you shorten the standoffs? I have a 3s 1806 build and I want to get it as light as possible.

 

[mpbiv]

How much weight do you lose when you shorten the standoffs? I have a 3s 1806 build and I want to get it as light as possible.

I have no clue, and most likely on the Blackout the weight loss from chopping the standoffs isn't much because they are plastic/nylon.

When it comes to weight reduction, without changing out electronics for lighter ones, the other areas where I can reduce weight are small. But when you reduce the weight in several areas, it can have an additive effect.

Honestly I will be very surprised if I can get this frame down 50g. That is a lot, but maybe 20g, that might be more realistic. The closer I can get to the class minimum 300g, the better it will fly.

My Twitch Frames Acro Quad with my FPV pod was actually underweight, and I had to add weight to it last weekend to race with MultiGP 3S Spec. But at almost exactly 300g it was very nimble and had a good power to weight ratio on 3S.

 

[mpbiv]

DUUUUUUUUDE!!!

This is so cool man! Great build!!! Wow the cuts came out PERFECT... I think I'm gonna have to send you my plates for milling in the future lol!!!

I think yours came out even shorter overall, I used 12mm standoffs but with my extra arm spacers is probably around 18mm of spacer.

The 3D parts you designed are really nice, I had to fandangle mine together from aquarium hose to make the top plate work out.

Wow I'm really happy to see this. I built up another lowrider but 5" and with 2300kv too.

View attachment 56062

Lookin forward to more updates

Thanks! Like I said, it was your build that inspired me to keep my Blackout and start this project. This is turning out to be a fun project!

I noticed in your original build you went with titanium hardware, which I assume was a compromise to reduce the weight compared to steel hardware while still maintaining some strength. I am going to try aluminum hardware because it is even lighter, but it is definitely weaker than steel or titanium, so we will see how durable they are in the long run. I will definitely be crashing this thing.

Definitely let me know if you have any feedback!

 

[C0d3M0nk3y]

These pictures hopefully answer your question.

They do. Thanks!

Could I go lower on the camera?

I was actually thinking about the opposite. I wonder how much taller the printed piece surrounding the camera would need to be to mount the camera on top of the plate without cutting it.

And here are what the guts look like. It actually wasn't that hard fitting everything in there.

It looks good. I was expecting quite a tighter fit for everything with standoffs that small.

 

[jipp]

looks good. i would not recognize it as a black out. 3d printer nice tool to have in this hobby.

 

[mpbiv]

Aluminum Hardware arrived. Everything was ordered from Fastener Express. Decided to go purple!

Initial weigh in prior to hardware swap:


Total weight of steel hardware used (plastic container is tared out):


Weight of quad with all aluminum hardware:


Considering the steel hardware weighs ~30g and aluminum is roughly 1/3 the density, it makes sense that the total reduction was 20g. Now I'm even closer to the 300g minimum, although getting another 30g out may not be possible.

Next step, shorten the ESC wires now that the 5" arms are installed.