Quad Bloody Wonder (Inspired by Flying201's Twin BW)

[Flat4]

This is going to be my sort of build log of a quad motor bloody wonder, inspired by Flying201's Twin Bloody Wonder. As usual I never think to take pictures as I go until I'm hours into it, so bear with me, this won't be the most visually impressive build log. Thanks again Flying201, for inspiring me to get to work on this, your twin bloody is awesome, hopefully this can follow in it's footsteps.

A few nights ago I stumbled across Flying201's build log of his Twin Bloody Wonder. Being that I currently needed a new fpv air frame, and seeing how sweet his twin was, I thought about how I could go about making one with what I had laying around. My mind immediately went to my plethora of spare mini quad motors and esc's, they needed a home, but how to incorporate them? I first thought since Flying201 up scaled his a bit to better accommodate the two standard sized BW motors, I'd just make a normal sized one with two mini quad motors. I entertained that idea until I cut out the wing and realized how tiny two 5" props would be on it, so quad bloody it is!

I started out by simply cutting out a standard wing for the BW, as well as the wing spar. I then added a 1x6x750mm carbon strip in between the foam spar as I folded it over for added rigidity. Next I marked out my spacing for the motors, and put some thought into the wiring and esc placement. I decided to cut holes in the bottom of the wing for the esc's to sit flush with, and allow air to pass over them. Now knowing what I needed for wire length I began my harness for everything. A few hours, and quite a bit of head scratching later I had everything wired up and the motors spinning in the proper directions.

Next I cut out roughly one inch squares of some 1/8" hobby ply I had around to use for motor mounts. After drilling some holes for the motor shaft, and screws to go I had all my motors mounted, ready for installation. I carefully laid everything out in its spot and used some hot glue to tack the wires down in place to allow me to fold the wing over. Here is where I finally thought, hey you should take some pictures. Oh as you can also see in the pic below, I added some foam behind where the motors will mount to give a bit more surface to glue them to.



Next I folded the wing over, and glued it all up, again without taking any photos because let's be honest who really comes into build threads to see pretty pictures of well crafted airplanes? Afterwards I went ahead and glued on the motors, and threw some props on to make me feel some sense of progression. Surprisingly all the motors spin, not only that, they spin the right directions! Oh and what's this, I remembered I had a camera again?




Both of these shots are of the underside of the wing.

Well, that's it for the moment. I figured getting all that done would be the longest part of the process, and I was right. I could have made 2 standard BW's by now, but I think this might be worth it. Stay tuned for more, should have a good chunk done tomorrow night as I'd really like to maiden it this weekend.

Anyone know of an average AUW for a standard Bloddy Wonder? I never weighed any of mine and I'm curious as to how this will stack up. Currently I'm up to 290 grams as you see it in the last picture.


Update 1

So earlier today I finished off cutting out and taping up all the remaining piece's before work. Well having been home for a few hours now, I pretty much finished everything else up. I've yet to attach the vert stabs so they don't get in the way of me running the pushrods. I just slid them in the slots for the photos below to complete the look. My flying buddy is going to bring me some linkage stoppers tomorrow morning so i can finish up the control surfaces, and off to maiden. Differential thrust has also been setup, and seems likes it's still going to have insane yaw authority even without a rudder.

The one thing that's really turning me off is the front, that square tube is really bothering me. Problem being I cut the fuselage to a pretty tight fit to my fpv board cam, not really giving me any room for modification. If anyone has any simple ideas for adding some shape to it, I'm open to suggestions. I am going to probably take about an inch off the length of the nose. I made it long intentionally because I was unsure of how the CG was going to end up, but it's not a problem at all. I think that's about it for now, enjoy the pics.






Fun Fact: These motors once flew my 250mm sized mini quad that weighed 610 grams, so this should be fun.












Update 2

So I went out early today and had an extremely successful maiden, really thrilled with the way this flies. I ran home with the intentions of uploading the video's, but my flying buddy convinced me to slap my fpv gear on it, and go fly with him and his blackout mini quad. So I sadly yanked my 5.8 system off my mini quad and off we went. Man I thought the maiden was fun, holy cow this thing is nuts under the goggles.

My friend also got some fantastic areal footage from his blackout. Bad news is I have about an hour of footage to sift through and edit now. I'm uploading maiden video, my friends' first flight on it, and some on board video to youtube as I type this. All off these videos are just raw footage, and the on board video in not for those with motion sickness. It's not shaky video at all, however we were so impressed with how well it flew on our first tries, that we didn't hold back much on the second.

Sadly, as you'll see as soon as I get the videos edited, I wasn't to kind to it during the fpv portion of the day. First flight I tossed it up and went to head it out away from us so I could toss my buddy the sticks and through my goggles on. Some how I lost orientation and stuffed it in the ground nose first. Took the hit just fine, the bottom of nose was all that took damage, and it wasn't much. Later I dumped it taking a weird angle under the arm of a backhoe. That did a bit more nose damage, but still completely flyable. The added mushiness to the nose however turned my beautiful jello free video, into something not as good. Still not terrible, but seeing how good it was to start it kind of bums me out. All in all shes still flying great, but not as pretty as she was when the day began. Life of an RC pilot I suppose.

Pictures of the damage. Awesome note here, I flew her back to me from quite a distance away the those props in that condition. The noise it made as that one blade of the prop on the outer starboard side slapped against the wing was horrendous. But yet it still flew back to me as nothing was wrong, blew my mind.





Videos will be up as soon as youtube finish's editing the maiden, you can blame that on my friend who just had to drop an F bomb, on a video he recorded in 4k on his brand new galaxy s5, so it's now going to take extra long to edit. Don't worry, I yelled at him already for it.


Videos are up!!! Hopefully I'll have some of the FPV videos up tomorrow. Enjoy these for now.

Maiden

My friends first flight on it

On Board Video

It's first FPV video, and chase video rough edits have been done.

First FPV Flight for the Quad Bloody Video Highlights

Chase Video Highlights, Courtesy of my friend and his blackout mini quad.

Update 3

I just wanted to add in the list of electronics, and materials used.

Dollar Tree Foamboard
Motors - 4x RCX 1804 2300kv
ESC's- F-12a Fire Red Series (simonk flashed)
Servos- http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=23594
Pushrods- 1.8mm Carbon Rod
WingSpar- 1x6x750mm Carbon Strip
Motor Mounts- Roughly 1inch squares of 1/8" hobby ply
Lots of Hot Glue
Packing Tape

 

[stay-fun]

Great job dude, I'm looking forward to the maiden! It seems like you're using counter rotating props? Are you going to use differential thrust? Are you going to add a rudder? (well a rudder is probably overkill if you have diff thrust).

My standard bloody wonder weighs 405 grams, excluding battery. Has an NTM 28-26 motor.

 

[Flat4]

Great job dude, I'm looking forward to the maiden! It seems like you're using counter rotating props? Are you going to use differential thrust? Are you going to add a rudder? (well a rudder is probably overkill if you have diff thrust).

My standard bloody wonder weighs 405 grams, excluding battery. Has an NTM 28-26 motor.

Thanks dude, appreciate it, I'm looking forward to the maiden as well .Yea I am using counter rotating props, the two outside motors spin opposite, as do the two inside motors. Currently I'm on the fence about rudder, not sure if I'll need it with the dif thrust, also not sure if it's going to be worth the weight. I really did originally want a rudder combined with dif thrust for crazy yaw authority, but again don't know if it's needed.

This bird is def going to end up on the heavy side, figure I'm at 290g now, add 100g in fpv gear, 150g for battery and I'm now at a standard bloody weight without servos, a fuselage or tail made yet. I think I'm going to go cut out the rest of the pieces now before work, and get a better idea of this things weight. Will have updates for sure tonight.

 

[Tactical Ex]

This looks so cool. Cant wait to see it fly. My 2 cents... cut weight wherever you can; if that means no rudder, so be it. Every time I modded my BW I had to adjust the cruising speed up by like 5%, it just didn't seem to handle extra weight well. You'll have the functionality with differential thrust, no need for a rudder.

 

[Flat4]

This looks so cool. Cant wait to see it fly. My 2 cents... cut weight wherever you can; if that means no rudder, so be it. Every time I modded my BW I had to adjust the cruising speed up by like 5%, it just didn't seem to handle extra weight well. You'll have the functionality with differential thrust, no need for a rudder.

Thanks for the feedback, and yea I decided to nix the rudder. Just finished cutting out the rest of the pieces, but now it's time for work. Hopefully I'll have it close to done tonight.

 

[Flat4]

Pretty much finished up the plane this evening, check the first post for more pics, and details.

 

[flyin201]

Haha wow! You took it to the next level, looks great! That should have some very interesting flight characteristics! I can attest that the wonder design doesn't handle weight well. On my twin it had a higher stall speed than the single and much higher when carrying the GoPro. As far as the rudder goes diff thrust should be more than enough so I would say you can skip the rudder. My twin wonder had no diff. thrust and the props weren't counter rotating and it almost didn't need rudders either. In fact I only really use the rudder to trim it out so it tracks straight. Great job!

 

[stay-fun]

That thing is soooooo effing epic man! I love it!

Hmm, weight isn't good? Is it possible to make the wings slightly longer, and/or add undercambered wing tips? That may help in reducing the stall speed...

 

[Flat4]

That thing is soooooo effing epic man! I love it!

Hmm, weight isn't good? Is it possible to make the wings slightly longer, and/or add undercambered wing tips? That may help in reducing the stall speed...

Thanks dude, I think it looks quite BA myself. The weight isn't anywhere near a problem as I just maidened it, and it flew amazing. Couple of clicks of trim required but that was all, uploading the videos now, should have them on the thread in a bit.

 

[stay-fun]

Nice man!

So, do you have a thrust angle on the motors? From the pictures it looks like you mounted the firewalls directly agains the spar? Where is the shaft compared to the wing, is it higher/lower, or right on the leading edge hight?

 

[stay-fun]

Oh and, what's the weight of your plane? (excluding battery)

 

[Tritium]

A 12 Bladed Bloody Wonder. I think you need to name it "Jason"!
Nice work.

Thurmond

 

[Flat4]

Nice man!

So, do you have a thrust angle on the motors? From the pictures it looks like you mounted the firewalls directly agains the spar? Where is the shaft compared to the wing, is it higher/lower, or right on the leading edge hight?

No the motors are mounted at a 90 with the flat bottom edge of the wing. The shafts of the motors end up perfectly in the center line of the wings airfoil. I'll take a pic that will give a better reference.The motors happen to be the same diameter, or very close, as the height of the BW's airfoil, I figured I wouldn't need all that much of a thrust angle so I decided to leave it out for simplicity. It does climb a bit under full throttle, but it's completely manageable.



I immediately went home before after the maiden and slapped my fpv gear on it, then ran out with my friend. Have some awesome shots, and a few crashes , but she still lives! The fuselage has seen better days, and a few props were lost in the action, but man what fun. And I got some amazing footage, just a lot of it so now I need to take time and edit. My friend also got some amazing chase shots with his blackout mini quad, again a lot of footage though so give me a bit to sort through it. I'm going to update the first post with the maiden video in the meantime.

 

[Flat4]

A 12 Bladed Bloody Wonder. I think you need to name it "Jason"!
Nice work.

Thurmond

Thanks, I might just have to with the way I was chopping up trees today. Didn't end the day as pretty as it started, but boy did I have a good time. Videos to come shortly.

 

[Flat4]

Oh and, what's the weight of your plane? (excluding battery)

440 grams I think it ended up without battery. This thing is hilarious though, will go straight vertical forever at half throttle. So funny watching a BW just climb straight up at around 20 MPH.

 

[stay-fun]

440 grams I think it ended up without battery. This thing is hilarious though, will go straight vertical forever at half throttle. So funny watching a BW just climb straight up at around 20 MPH.

That's cool! I have a BW with symmetrical wing, and a sunnysky 2216 1200 kV with 8x6 prop, it has unlimited vertical but I should check if it would do that at half throttle . I'm running it on 4s 1300mAh. Which battery do you use?

I can't wait for the video! Man this makes me also wanting a quad BW... :applause:

 

[Flat4]

That's cool! I have a BW with symmetrical wing, and a sunnysky 2216 1200 kV with 8x6 prop, it has unlimited vertical but I should check if it would do that at half throttle . I'm running it on 4s 1300mAh. Which battery do you use?

I can't wait for the video! Man this makes me also wanting a quad BW... :applause:

I was running just a 3s 1800 40C. These esc's won't take kindly to 4s power. I did have to switch out the original 5x3x3 props I had on it after a bit of an incident to 5x4.5x3's and man did it haul with those. My buddy was chasing me with his blackout all day and was yelling at me to slow down after I put those on, I was at half throttle already lol.

Videos of the maiden are up in the first post, check them out!

 

[stay-fun]

Wow great videos! And man that thing hauls indeed! What a sound... Like a 4-engine plane with tiiiiny motors (the high pitched sound). And seeing the power it has, no 4s required indeed!

Differential thrust isn't doing much? Too bad... It does seem like you're flying bank&yank all the time indeed. I can't really fly bank&yank, even if I don't have a rudder, my rudder stick will move. It's muscle memory

With all the bloody wonder stuff going on, I just HAVE to share my symmetrical wing. I've uploaded it as an article a while back but it's still pending approval... So I just put it on the forum. Shameless plug.

 

[Flat4]

Wow great videos! And man that thing hauls indeed! What a sound... Like a 4-engine plane with tiiiiny motors (the high pitched sound). And seeing the power it has, no 4s required indeed!

Differential thrust isn't doing much? Too bad... It does seem like you're flying bank&yank all the time indeed. I can't really fly bank&yank, even if I don't have a rudder, my rudder stick will move. It's muscle memory

With all the bloody wonder stuff going on, I just HAVE to share my symmetrical wing. I've uploaded it as an article a while back but it's still pending approval... So I just put it on the forum. Shameless plug.

Man, I totally remember that article now, and am kicking myself for forgetting it. I would have loved to steal your idea for the symmetrical airfoil on this, because I believe that would have given me the result I was looking for from the dif thrust. As it is now, say for instance if I used left rudder, the right wing would pitch up because the increased airflow over the the flat bottom airfoil, as the left dipped with it's reduced airflow, along with the standard yaw effect you would expect. A simple right aileron input and some up elevator would correct it, but that's not what I was after. The whole reasoning in my head behind this is I wanted to be able to knife edge and flat turn on my fpv plane. Specifically because all I really do is proximity flying, and would love that additional mobility past just bank and yank.

You got me really wanted to remake this thing now. It could use it, the front end has seen better days, but the time this took, ughhh. Alright less typing more editing, there is this on shot my buddy got that is amazing and I need to show people. May just make a quick clip of it. Also the shot he got was from a run I did without my mobius on, probably the coolest thing I did all day too, would have been bummed if I had no footage of it. Alright seriously back to editing.

 

[stay-fun]

Haha! Well you're very welcome to copy my design, that's why I put it on the forum in the first place!

I do notice I need opposite aileron input to make a flat spin, and it's more like a flat turn than spin anyway . Differential thrust should definitely help, I'm sure you've seen the original cruiser episode. Even with a symmetrical wing, the wing that has most speed (right wing in a left turn in your example) will still produce more lift than the other wing. This is because there is an angle of attack involved, which is not zero, because if it was you would be descending. A symmetrical wing with 0deg pitch does not produce lift.

Maybe a flight stabilizer, like the guardian (have one, still got to test it) or the APM is able to make you do flat turns/spins without the hassle of giving aileron corrections to keep the plane flat?

I also have new modifications in mind for my symmetrical wonder: I need larger winglets for increasing knife edge performance, and I want a smaller vertical stab (possibly combined with larger rudder).