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Mustang7302's Bat Bone Build Log

#1
For the past several weeks I have become interested in building a tri-rotor. I love the videos that the FliteTest group does and have spent countless hours watching too many of their videos for both entertainment and absorbing knowledge. So it was only logical that I would show my love the FliteTest guys by waiting for their release of the Bat Bone frame.

I will post updates as things arrive (including when the order was placed and its total), pictures of the build process, little tips or tricks I use, and answer questions. Here are the parts I have currently planned to use; however things could change...

Update: An updated powerplant was used to eventually get this frame into the air. Please see the following post for details - http://forum.flitetest.com/showthre...t-Bone-Build-Log&p=82338&viewfull=1#post82338.

Frame:
Flight Controller
Powertrain
Battery
Transmitter / Receiver


Minus the transmitter, battery charger, and extra spairs; this build is about $300 for the major parts. However that doesn't cover things like connectors, extra wire, heat shrink, velcro, zip ties, servo extensions, and programming/flashing (for FCB and ESCs) tools which I estimate to be an additional $60 so far.

Thanks again to the FliteTest crew for doing such great work in their videos, articles, and store!

Updates:
  1. Bat Bone frame, Rotor Bones mounts, Rotor Bones booms, and a T-shirt arrive from Flite Test!
 
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#2
not bad choices- if this is your first multirotor i would definitely look at dumping the cf props and go for some gemfans. 4s batteries arent cheap either....it looks like your locking yourself into 4s with that motor also. itll run in 3s but im sure youll be swingin 13" plus to get viable thrust with a 3s. another thing i noticed is you are well set into parts that cant be had in the us as far as components go, if you're ok with having to wait 3 weeks plus for replacement parts then your good, otherwise i might look to another vendor with more readily available stuff as far as the motor/esc/servo goes. i use sunnysky 2216-800 and as far as quality goes id put them up against anything in the hk shop, and when i need parts theyr'e to my door within the week granted theyre a little more expensive but if you put time and quality into the equation its a no brainer. the turnigy stuff is generally of good quality but if somethign happens and you need customer service or a part, youre either just plain screwed in case of warranty or your gonna wait a month plus to receive your stuff.
i order from hk out of neccessity only- as in kk2 board and random items i dont mind waiting forever for.. id rather pay a little more and have the product before the season is over lol.
 
#3
I will be buying plenty of spare props when I place the order with them; and at $1.35 each I am not going to be terribly upset when I inevitably break one. Once I have run out of props from that initial order and want something quicker, I will be at the mercy of what ever the local RC Hobby shop has.

Running calculations with the eCalc; I found that the 800kv motor with a 4000mAh 4S battery swinging the 10x4.5 prop gave me the combination of power (<=40% throttle for hover) and efficiency (10-15 minute flight time) I was looking for. I could have gone with a faster motor with a smaller prop, but found many combinations to be less efficient on battery consumption. I will be very eager to see that these calculations translate into the real world like I hope.

I've used Hobby King to source and build a spec sheet of parts because they have the best selection and ease of navigation of any site I have looked at. The few american based sites I have looked at had motors for three times the price and a dismal selection. If there is another vendor who has a good selection and decent pricing, please let me know!

Additionally, this is going to be a drawn out build. Trying to keep the wife happy by spreading out orders to be <$150 each; which would be at least eight weeks the expenses are spread out over. I already have the transmitter and receiver, just ordered the HK KK2.0 FC and FliteTest parts this week, and probably wont order Motors/ESCs/Props/Servo for another two weeks. Beyond that order is two more for the small parts and batteries/charger.
 

Tritium

Amateur Extra Class K5TWM
#4
Beware that the rotor bones construction method does not lend itself well to larger motors than it was designed for. It should be constructed with motors of about the same spec as the original. Large thrust can pull apart the snap lock assembly's. You could of course glue them.

Thurmond
 
#8
Update: An updated powerplant was used to eventually get this frame into the air. Please see the following post for details - http://forum.flitetest.com/showthre...t-Bone-Build-Log&p=82338&viewfull=1#post82338.

Update 1: Bat Bone frame, Rotor Bones mounts, Rotor Bones booms, and a T-shirt arrive from Flite Test!

Ordered: Wednesday, June 19th, 2013
Arrived: Monday, June 24th, 2013
Order Total (with shipping): $120.40

The goodies fresh out of the bubble wrap envelope from shipping.
  • 1x Rotor Bones Bat Bone Frame, with Hardware and Battery Straps
  • 1x Straight Rotor Bones Mounts, with Hardware (2 Units)
  • 1x Tilt Rotor Bones Mount, with Hardware
  • 3x 1/2" Square 10" Long Wood Booms (2 Units)
  • 1x Flite Test T-Shirt


I started off by un-packaging everything and fitting the pieces of the Bat Bone frame together. Ended up holding it together with four of the screws in the center area to keep from loosing the pieces. I then moved on to putting together the Rotor Bones straight mounts.



There are a lot of little pieces to punch out of the components of the mounts, some of which happen to blast off at the speed of light never to be found again (or until the vacuum finds them). Once everything is punched out, they are fairly straight forward to put together; kinda like a assembling a lego set (for ages 4+) with only the final picture to figure out where each piece goes. Of course I didn't think to see if there were instructions online before I started, but as I type this I took a gander at the article archive and found the Rotor Bones Straight 13-370 BUILD page.

Having conquered the straight mounts, I moved on to the tilt mount.



As you can see, there are quite a few more pieces; I rate this lego set for ages 10+. Fairly straight forward to figure out, just be cautious to not lose one of the pieces or tiny hardware pieces. Here is the article for the Rotor Bones Tilt 13-370 BUILD page, which again I found after the fact.

So now all of the Flite Test bits are assembled and its time to put the parts together for more pictures and a loose mock up.





Over the weekend I will likely tackle getting the booms drilled for the frame and mount, as well as getting some kind of finish put on the naked wood. It also looks like the KK2.0 flight controller made it into the states yesterday, so I hope to see in the mail box early next week.
 
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#9
Beware that the rotor bones construction method does not lend itself well to larger motors than it was designed for. It should be constructed with motors of about the same spec as the original. Large thrust can pull apart the snap lock assembly's. You could of course glue them.

Thurmond
That's the second of third time I have seen that mentioned. I have had a hard time figuring out what constitutes a 370 sized motor when looking at the plethora of options out there. I have considered a couple of things I intend to do when the time comes to mount the motors to ensure a strong mount; I will detail these later when I get to those steps.

any buddy codde? for the motor
I do not have buddy codes at this time.

I juz bought a motor have a buddy code here. NTM Prop Drive 28-30S 800KV / 300W Brushless Motor (short shaft version)http://www.hobbyking.com/buddy.asp?c...3-5FF3E8E42098
Congrats on the purchase!

I have buddy code. You all can use to save money
Please keep the soliciting to a minimum in this thread, thanks.
 
#12
Unless, of course, it's Flitetest products. . . :applause:
Supporting the group that hosts the forum, great content, and products is not the same as pimping referral codes/links for third party vendors. As it is, I have plenty of links to HobbyKing in the original post, for now; this is subject to change if I find a different source for parts.

Is that servo too large?
The spec card that came with the kit for the tilt mount says the cut out is 12mm x 23mm. Looking at the specs from Hobby King's page for the tail servo I have listed, it shows a 12.1mm x 23mm aluminum case. It will be a snug fit, but a flat file would also make quick work of relieving the delrin material.
 
#13
Ordered motors, ESCs, props, tail servo, and servo extensions through RCTimer today; updated the original post with parts ordered versus old parts in the specs. Also placed another order to Hobby King for supporting materials like connectors, heat shrink, wire, velcro, and a prop balancer. Only thing left to order will be the batteries, charger, and a meter which will wait another two weeks or so. I do have two 3S 1300 LiPo batteries laying around which I will use to get everything setup with, but may not actually make any flights with.
 
#14
Will be keeping an eye on this thread progress, very interested in the bat bones tricopter.. Its an unique looking frame and looks ideal for easy fixing out in the field.

I really hope they have the v-tail mod available soon, so i can order from the store.

I have not seen much information regarding mounting larger motors, and the information surrounding this is a bit vague. Are the motor mounts pretty strong?... I'm surprised the mount design position is overhanging the frame, more support/less vibration would be achieved if the position was directly over the landing gear.

Perhaps this would allow bigger/heavier motors to be fixed down securely..?
 

FlyingMonkey

Stuck in Sunny FL
Staff member
Admin
#15
That's the second of third time I have seen that mentioned. I have had a hard time figuring out what constitutes a 370 sized motor when looking at the plethora of options out there. I have considered a couple of things I intend to do when the time comes to mount the motors to ensure a strong mount; I will detail these later when I get to those steps.
I'd look for something that's producing about 100 watts, or up around 20 oz of thrust with an 8" prop. I'm not going below 1000 KV again. I tried it, and it was just too sluggish. I like 1300 kv.
 
#16
Update: An updated powerplant was used to eventually get this frame into the air. Please see the following post for details - http://forum.flitetest.com/showthre...t-Bone-Build-Log&p=82338&viewfull=1#post82338.

Update 2: KK2.0 Flight Controller arrived from Hobby King!

Ordered: Wednesday, June 17th, 2013
Arrived: Monday, June 28th, 2013
Order Total (with shipping): $44.32

Got the KK2.0 Flight Control Board out of its packaging and proceeded with figuring out how it will be mounted to the body. Since I intend to keep as much of the components as possible inside of the Bat Bone body, I found the easiest way to keep the FCB in place was to use the lid from the foam box as a base to center it in the middle of the frame.



Put electrical tape on the bottom of the FCB to give a smoother surface for the double sided duct tape to secure it to the foam lid. Super simple, fits perfectly, and will still give the FCB a bit of vibration dampening.

Here is a shot of the FCB inside of the frame.



Centers in the opening, again, perfectly. I figured the wires to connect to and from the FCB would stick up above the top of the body, but I have plans on how to make it look decent when the time comes.

Next was to attach the battery straps to the bottom of the Bat Bone body, again double sided duct tape is used to keep them from slipping around.



About this time it dawned on me that it would be convenient if the vertical support pieces stayed in the bottom of the body. So I broke out the hot glue gun and put dabs of glue on the bottom side of the body at each end of each support piece; just enough to keep them from falling out, but still easy enough to remove if needed and clean up later.



I went ahead and marked the booms to be drilled, took them out to the garage, and used the drill press to make the holes.



I wanted to do something to the bare wood, and the wife suggested something green. So in what has taken the most of amount of time yet was to lay down the base "black" color, mask off each boom with painter's tape, measure and cut three stripes on each boom, and apply the florescent green bands to the booms.



Bolted the motor mounts/landing stilts to each arm and bolted each boom to the bottom half of the body while I wait for the orders from yesterday to come in.

 
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#17
Will be keeping an eye on this thread progress, very interested in the bat bones tricopter.. Its an unique looking frame and looks ideal for easy fixing out in the field.

I really hope they have the v-tail mod available soon, so i can order from the store.

I have not seen much information regarding mounting larger motors, and the information surrounding this is a bit vague. Are the motor mounts pretty strong?... I'm surprised the mount design position is overhanging the frame, more support/less vibration would be achieved if the position was directly over the landing gear.

Perhaps this would allow bigger/heavier motors to be fixed down securely..?
The V-Tail is pretty cool and may end up doing it one day. For now, just trying to get it together and in the air.

The motor mount plates are pretty stout, the G10 material has no give. The weakest part of the mounts is the snap together nature of the stilts to the to the G10 plates which bolt to either side of the boom. I can't imagine how the G10 mounts will break before the wooden boom or the zip ties strapping the motor to the plates.

When I marked where to punch the holes in the boom, I pulled the mounts further in on the boom so that the back of the boom is flush with the center hole. This creates less over hang to stress the G10 material. I also drilled an adjacent hole to the mounts two holes (you can see this above) which I may end up using to bolt the two side delrin plates together with.

I'd look for something that's producing about 100 watts, or up around 20 oz of thrust with an 8" prop. I'm not going below 1000 KV again. I tried it, and it was just too sluggish. I like 1300 kv.
The 750KV, 4S, and 10x4.5" prop calculates to 155W on the ecalc; which I guesstimate is close to a 1KG of thrust per motor. Since I intend to swing a ~4000mah battery under the copter for longer flight time, I want to make sure there is enough power to lift it as well as having enough left over power to carry additional payload (camera equipment).

Although I have no experience in multi-rotor setup, I hope that between the 4S voltage and SimonK flashed ESCs that it will be plenty responsive. Time will tell and I just might end up going to a different setup later on down the line.
 

FlyingMonkey

Stuck in Sunny FL
Staff member
Admin
#18
I can't imagine how the G10 mounts will break before the wooden boom or the zip ties strapping the motor to the plates.
I can help you there.

Drop the craft from about 20 feet up, and have it land almost perfectly square and level. The weight of the motor refusing to stop it's descent is enough to snap the motor mount clean off at the bolt hole.
 

colorex

Rotor Riot!
Mentor
#19
I pulled the mounts further in on the boom so that the back of the boom is flush with the center hole. This creates less over hang to stress the G10 material.
Can't really see how much this would help as the biggest force is the thrust upwards. The motor doesn't weigh much at all... Unless you were to crash upside down, then it would help.
 
#20
I can help you there.

Drop the craft from about 20 feet up, and have it land almost perfectly square and level. The weight of the motor refusing to stop it's descent is enough to snap the motor mount clean off at the bolt hole.
Setting the mounts in just a bit will help with that, I would think.

Can't really see how much this would help as the biggest force is the thrust upwards. The motor doesn't weigh much at all... Unless you were to crash upside down, then it would help.
If upwards thrust is the issue, flexing the G10 mount, I have an idea to reinforce the mount with a plate of kydex cut to a similar shape and holes.