Working my way up on the drone building world… lol

Whilst browsing UnmannedTech’s bargain bin I saw a mob7hd which was missing a motor and other possible problems and had the idea of converting that into a Toothpick with a HD DVR (Caddx Turtle v2).
Fast forward some days, I now have almost everything I need for the build, missing the motors, but have decided to start putting things together.
Sourced a suitable canopy from thingigverse. I had the prints done elsewhere and have just received them, so I was eager to see how it all looks on the frame  It’s not all on the frame yet, but at least now I have a better idea of how things might/should work all together. It also has given me a chance to identify a major pain, which is the diamond vtx that came on the drone, this thing is really getting in the way of the build, so I might need to discard it for a smaller solution (might do a swap with the Meteor75 vtx , but not sure yet).

• Actually the big challenge on this build is the fact that the caddx turtle dvr board is a 20x20 mount, hence the height of the stack
  

I have not added the FC on the stack bc as it is now it doesn’t fit. The power cable is soldered right next to the USB plug on the bottom side, and this is keeping it from fitting on the frame (its a crux3 frame). But the overall height should not change with its added, since I left the FC gummies on the stack as a place holder…
Well, enough chat… here is what it looks so far:






Motors are coming from China, who knows when that will arrive. I got some dirt cheap 1104 4300kv, same as the BabyApes, and initially I’ll run it on 2s. I will most likely settle on the gf3018 bi-blades, but will try out the 3016 tri-blades, and a 25xx tri-blade as well… The esc on this board is only 5a, so I’ll have to be very cautious setting up.
Until the motors arrive I have some solder work to do as well; de-solder battery lead, the motor plugs, and the led. Will add an elrs rx and a battery lead with a cap on… Also, since I’ll be flying this on 2s at first, I’ll put together a couple of adapters from bt2.0 to xt30 and gnb27 to xt30, this way I don’t need to buy more batteries or charger for the time being… lol times require me to be cheap…

Not sure I like the height to much and might ditch the turtle eventually and use it on a bigger frame build, but for now I'll leave it as is..

That’s it for now, just wanted to share the experience with you all…

Not in the mood of soldering today but I did remember I had another frame laying around which could be used for the build.
Dug it up from a dark corner and put everything on to it, minus the motors… This should be the final stack format should I keep the diamond VTX. All I need to sort out a bit better is the spacing between the canopy and Turtle board, as well as the VTX and adapter plate…
Also put everything on the scale and the AUW should be around 95g, +/- a few grams depending on the batteries being use.
If used with the 3018, as per motor chart, on 2s I’ll be getting around 5:1 ratio and on 3s around 7.5:1. On 3s it seems to be performing closer to what is expected of this type of class…
Here’s how it looks on the other frame:

Which version of the Mobula7 board do you have? I believe both are rated only for 1-2S, so don't try plugging in a 3S. (seems old one is 1-3S and newer one 1-2S). The old version also only has 5A ESCs which may be a little tight for 1104 motors running 3" props.

I had an old mob6HD setup running on a 75mm whoop frame and enjoyed that a lot. It has the Runcam Split 3 Lite which is similar to the baby turtle and running 1102 motors. A little clumsy for a 75 whoop, but flew well enough and lots of fun.

Do you have the Diamond VTX with DVR? If so, using that with the turtle may add extra latency. That tall stack though, looks a little scary, but if you don't crash hard it maybe fine. Since your new frame has the outer holes, maybe you can repurpose the original canopy with some standoffs.

(24-Feb-2023, 04:24 PM)mstc Wrote: Which version of the Mobula7 board do you have? I believe both are rated only for 1-2S, so don't try plugging in a 3S. (seems old one is 1-3S and newer one 1-2S). The old version also only has 5A ESCs which may be a little tight for 1104 motors running 3" props.

I had an old mob6HD setup running on a 75mm whoop frame and enjoyed that a lot. It has the Runcam Split 3 Lite which is similar to the baby turtle and running 1102 motors. A little clumsy for a 75 whoop, but flew well enough and lots of fun.

Do you have the Diamond VTX with DVR? If so, using that with the turtle may add extra latency. That tall stack though, looks a little scary, but if you don't crash hard it maybe fine. Since your new frame has the outer holes, maybe you can repurpose the original canopy with some standoffs.

Its the one with the V2.0 FC, it comes with the caddx turtle v2 and 1102 10000kv motors. ESCs are like you say, 5a, but rated for 1-3s, which doesn't seem common nowadays.

The DVR I mentioned before is from the turtle v2 system.  The vtx is just a simple diamond shaped one, no dvr on it.

I will test it out with the 3018 bi-blades, 3016 tri-blades, and 2512 triblades.  I only know more or less what to expect in terms of amp draw on the 3018, which are both under 5 amps on 2 and 3s.  The other two sets I have no idea what its going to happen.  Will have to test out step by step by capping output on Bf.

I'm not digging about the height and weight, so I mind end up just removing the turtle system and run it with a regular analog setup, which will bring down the weight considerably, and probably be better to fly.

On my HM1103-7000kv motors running 3018 biblades on 2S, full throttle will pull approx 20A in flight so tri-blades on 1104s might be a little risky.

I'm looking at a 5A AIO and thinking to put 1103 motors with 3018 biblades, but just a little hesitant and thinking it might be better to stick with 1102 motors instead. Not worried so much about the continuous current draw, but a prop strike might go past the 6A burst rating?

I was basing amp draw on this chart:


supposedely from my motor.. dont know if its reliable or not..

That looks like it will be fun to fly. I’ve been gaining an appreciation for toothpicks these days- when I first started out, they just looked to fragile to me. They’re not, especially if they’re built light- but I didn’t know what I was doing so they certainly looked like I’d break it after one crash.

If you’re talking about these motors:
https://m.aliexpress.us/item/32568020040..._shipto=US
Then I would definitely start with a low motor output limit and work up slowly keeping an eye on peak amp draw. Their charts show that it pulls just under 6A, but, there are similar listings on aliexpress that don’t have any type of datasheet but list their amp draw as 6A to 12A.

Is there room in that canopy to wrap the turtle board in some kapton tape and tuck it up in the base? It’d save you some weight by ditching the tpu adapter and it’d lower your stack height. I’m not sure how you would access the sd card though- you might have to cut an access port into the canopy.

And thanks for sharing your build, I do love a good build thread.

(24-Feb-2023, 09:01 PM)Lemonyleprosy Wrote: That looks like it will be fun to fly. I’ve been gaining an appreciation for toothpicks these days- when I first started out, they just looked to fragile to me. They’re not, especially if they’re built light- but I didn’t know what I was doing so they certainly looked like I’d break it after one crash.

If you’re talking about these motors:
https://m.aliexpress.us/item/32568020040..._shipto=US
Then I would definitely start with a low motor output limit and work up slowly keeping an eye on peak amp draw. Their charts show that it pulls just under 6A, but, there are similar listings on aliexpress that don’t have any type of datasheet but list their amp draw as 6A to 12A.

Is there room in that canopy to wrap the turtle board in some kapton tape and tuck it up in the base? It’d save you some weight by ditching the tpu adapter and it’d lower your stack height. I’m not sure how you would access the sd card though- you might have to cut an access port into the canopy.

And thanks for sharing your build, I do love a good build thread.

I started with a whoop and the second was a toothpick, crux3 1s, its quite resilient, although I dont fly bandos or hard surface areas much. I enjoy flying it quite a bit and wanted to go up a notch, hence this project. I also want to build a 3 - 3.5 inch, sub 250 on a more traditional freestyle frame, albeit a more tamed fresstyle given the dimensions. I live in the city and don't have many oportunities to fly in places were I could justify a 5 inch for now, so I'll stick with the small guys, which I can fly anywhere pretty much.

Those are the motors indeed... I already suspected those datasheets might not be too accurate and your comment just reinforces that. So defitnitely gonna take things easy when starting out.  Also will start with 2s only  (2 1s connected together actually , so amp draw should remain on the low side at first, hopefully..

Not sure if that canopy could fit in such a way, but its not a bad idea at all.  If I do manage to chuck in there, it wont have anything to hold onto, although since it would be a tight fit might not need anything else to hold in place. I would, however, need to burn a slot for the SD card to go through.   Alternatively, I could look for another canopy that might be more appropriate for this method.  Will try it out and see if I can manage.
Thanks for the tip!

Oh those "emax" motors, I played with a set of those some time ago. I moved the electronics to another build since, but if I recall correctly they were not too bad, a little on the heavy side and not too efficient. I think the Baby Ape uses them. Prop screwholes are not standard so friction fit only, also don't lose those tiny M1.4 motor screws. With the low 4300kv, maybe 5A ESC will be fine for 2S.

You can also screw in the diamond vtx to the canopy and have the turtle board in the middle, then you can access the SD card without cutting. I think Betafpv had some canopies like that or you can print one if you have a 3D printer. Just have to make sure you have enough clearance between camera and VTX.

A couple dabs of hot glue would probably keep it in place, and the kapton tape would keep it from shorting anything out if it got loose.

A more appropriate canopy would certainly be cleaner, and I’m sure someone out there has designed a 25.5x25.5 whoop mount canopy with internal 20x20 holes for a similar purpose- but I’m a big fan of using what I’ve got and modifying it to work. That said, I do have a 3d printer. I don’t remember where you’re located, but if you’re in the US and you find a design you like, I can print you a couple and send them your way. Your only color option will be lava orange, but hey, it’s free.

I’m looking forward to seeing how this build works out, and I’m *really* curious to know if their datasheet is actually correct on the amp draw.

Something like this might work, depending on the clearance:
https://www.thingiverse.com/thing:4881492

Thanks for the input guys, and for the print offer Lemonyleprosy. I'm based in the UK, so it would make things a bit more difficult. Although I don't have a 3d printer, there are some guys that help out as well over here, so no worries on that side.

Regarding the motor.. yes 1.4 screw holes on the motor mount sucks, same as the tiny whoop, hope those hold well. But in the case of the props, I actually thought of that issue and looked for a adapter for t-muont, since I couldn't find one I designed one myself, very basic, on thinkercad. If I ever need them I'll print them up.

Regarding the fit on the canopy, haven't tried yet,will do tomorrow and report back.
This canopy was made for a project that had the 25x25 on the frame, adapter board, turtle dvr board, and vtx somehow stuck inside the canopy (a small unit was used by the creator). the canopy itself mounted on the turtle dvr. Thats why I'm struggled a bit, bc of my diamond shaped 25x25 board. I did manage to put the vtx inside the canopy, but it covered the mounting holes of the canopy and it was also a bit difficult to get it connected to the fc, So I discarded this option and did not think about an option of putting the turtle board inside instead until suggested here.

I did a bit of searching on thingiverse also (tbtw, tks for the link for that one Lemonyleprosy) and found one that is meant to have the turtle board inside the canopy followed by vtx, fc and frame (this is the one for reference https://www.thingiverse.com/thing:3703335 ). This one is an interesting concept bc the turtle board is "loose" inside and moves just enough for you to screw into the frame from above. It was actually made for a mob7 hd just like mine, but the person actually didn't mod it into a toothpick, so screwing downwards from canopy to frame actually makes sense, for my case iit will be a bit weird positioning having the nuts at the bottom of the frame, the screws will have to perfect fit and will thread lock will be my best friend.. lol But first lets try to see what I can do with what I got...

Just a quick update.. The turtle board will not fit inside as previously suggested.

Damn. Ah well, it was worth a shot.

Just build it tall. My PowerPick is pretty damn tall and it flies just fine.

Will have to do for starters... I was already working on an alternative, but it will need a lot of refinement before its usable.

Might do all the solder jobs tomorrow and leave everything ready for when the motors arrive.. Might be a stressful day.. lol