I started another build having got the bug for smaller quadcopters. ;D
I bought the frame and arms for the 330LF from Andy who's on this forum. I don't know him, but he's been super helpful with all my PMs and questions. He gives lots of good advice and clearly has lots of experience with the kits he's selling. So all the sensible things I do through the build are where I've followed his advice, all the daft things are where I've used my initiative. Which is half the fun - right?
The 330LF is a CF plate kit with DJI (or clone) F330 arms to make what looks like a mini discovery.
My plan was to build it up to use with 3S or 4S and Eagletree Vector and possibly a gimbal, I've got an Xaircraft one which is really light, but still to be tested.
Looking at motors I was trying to decide between the DJI E300 kit or Tiger motors and getting separate escs. In the end the fact that I could get the DJI E300 kit with motors, props and ESCs for £91 in the UK won the day. I also quite liked the idea of the DJI easy to remove props to be able to pack the quad down as small as possible to keep it in my car. The 9443 props would need to be cut down a bit as the max prop size for the 330LF is 9".
Here's the build so far with motors and ESCs fitted and LEDs on the arms to help with orientation. I need to sort out the wiring and a loom, but it's started. Super quick to build. To get to this stage took about 45 minutes.
Here's the 330LF next to the Hoverthings Flip 260. Not much difference in size. With the 6" vs 8-9" in props clearly the flip will be better with small gaps, but similar for transporting.
Next thing up is to test the DJI motor & props....
Testing the DJI 920KV motor with a variety of prop sizes.
Having gone for the cheaper option with the E300 kit I wanted to know how the motors would perform, what their efficiency would be for flight times and the impact of cutting the DJI props down to size. I couldn't find any data on web of the DJI motor performance.
I use my prop / motor testing rig and a current meter and tested an 8" phantom prop, phantom 2 prop, 9443 prop, 9443 prop cut down to 8.75" and cut down to 8".
I quickly realised that apart from the colour the 9443 and Phantom 2 props were exactly the same... :P
I'm an amateur at testing props so take the results with a pinch of salt, but I was impressed by how efficient the DJI motor was and how much thrust it developed. The full results are attached. With 4S the 8" prop at full throttle gave 980g at 12.2 amps and the cut down 9443 860g at 9.0 amps. 3S 8" prop gave 610g at 7.6 amps and the cut down 9443 522 at 5.6 amps.
The 9443 on 4S gave 1150g at 12.75 amps, but was too hot to sensibly run at that power. Though that was in my kitchen with limited air cooling.
I might have got my maths wrong, but the efficiency of the motor seemed much better than what I've seen quoted for tests on the Tiger motors (2208 1100KV) and they were the best I'd seen at this size based on data on the internet.
All the data and pic of the props tested are attached. No pic of the 9443 at 8.75" as I'd cut it down to 8" before I thought to take a photo! I'll need to cut the props carefully and balance them all, but looks like that should work fine and give plenty of power.
Here's the link to Andy's 330FPV post in the manufacturer's section. (Apologies if I'm not supposed to link to that section)
http://www.fpvhub.com/index.php/topic,19855.0.html (http://www.fpvhub.com/index.php/topic,19855.0.html)
Just picked up one of these frames myself! Keen to know how you get on with it and how you mount all your FC gear etc. This one will be for my Mrs to learn to fly on, so I'll use a Naza Lite w/GPS to keep it simple.
Went for the DYS 2212 1000kv motors and 20a EMAX ESCs.
That's some useful prop data there, cheers for posting that! The trimmed 9443 props work remarkably well. The ones I've tried I trimmed to about 8.5", and they seemed to fly about the same as an old style DJI 8" prop, perhaps with a bit less noise at high throttle settings.
I like the size comparison photos too. I have actually built up an airframe with some 2204-2300kv motors, for use with some little 6inch props. It flew rather well! The airframe is surprisingly about the same weight as a lot of the 250 sized kits with central "pods". The only difference is that it has a bit more frontal area (because of the size of the arms) so top speed is a little less.
Keep the updates coming though, it's good to see the layout of equipment that everyone is using.
I still keep going back to the DJI 2212-920 motors on 4s as my favourite power setup. It is nice and nippy, with plenty of power for flips and rolls, and you get a really good duration from a 2200mAh pack :)
Cheers
Andy
I've cut down the 9443 props that I got with the E300 kit to 9" and balanced them all today. I used an trick I saw somewhere on the web to use a drubro prop balancer to balance DJI props with the integrated nut. The tubing that holds the spring in place is just the right size to fit inside the nut and hold it in place.
So I have 4 props for the quad and a few spares ready to go. :D
The wiring for the escs is all sorted and the LEDs are working.
The layout of the 330 means there's plenty of space to fit everything in. More straightforward than the 260 quad I built last.
The LEDs look great, it's the first time I've used them so I'm not sure how well they stand out in daylight. I'm hoping they'll help me with orientation.
Next things to sort out are the VTX, flight controller and camera mounting...
Quote from: dani_r on December 19, 2014, 11:41:09 AM
Just picked up one of these frames myself! Keen to know how you get on with it and how you mount all your FC gear etc. This one will be for my Mrs to learn to fly on, so I'll use a Naza Lite w/GPS to keep it simple.
Went for the DYS 2212 1000kv motors and 20a EMAX ESCs.
Dani_r - I hope your build goes well. This is the first time I've built a quad like this one, so I'll be learning as I go.
Looks a like a nice build that :) I normally mount LED's the same way too. They stand out really nicely in the sky. Having them installed on a remote switch is always good for a bit of "turn the LEDs off for as long as you dare" type flying too!
That's a cracking tip about the prop balancer too. I made myself a little shaft with the same screw fitting as a DJI motor on to balance mine, but having seen this tip, it is much simpler!
With the camera mounting, if you are using a small FPV type camera (not a gopro or mobius) I normally just cable tie mine to the front ledge on the lower plate. Put the cable ties around the legs, and sit the camera on a bit of foam so it doesn't move around, and you are sorted. The cable ties give a little in a (small) crash, which helps preserve the camera.
If you want the FPV camera higher up to leave the front ledge free, a small bracket made from some aluminium angle (can be bought from model shops, B&Q etc) is the answer. That can be mounted on the upper plate, easily.
Cheers
Andy
Thanks Andy. I was just getting to thinking about how to mount the camera.
Most of the electronics are fitted now so almost ready for a test flight if the next few days...
I built up the quad with the flight controller on the the top plate with the aim of leaving the space in between the plates for the battery.
I discovered a couple of problems with that approach :(;
a) it looks like a dogs breakfast :laugh:
b) with the 9" props, the props are perilously close to the wires. :o
So I moved the electronics under the top plate with only the GPS mounted on top. It looks a lot neater that way.
All the electonics are sorted and tested. I've programmed the vector, checked motor directions etc so it's all ready to fly.
I've put the flight cam on the front step with a mobius mounted underneath it.
I got an extra top plate that I was going to use on top of the electronics on the top plate, but there wasn't room with the props. The 'spare' top plate is now being used as a battery holder under the quad. With some 3mm elastic it gives flexibility for a range of battery sizes and locations to get the CG right.
Using hobbyking legs cut down to 70mm I made some short legs to keep the battery and mobius off the ground and still keeping it all low profile.
First test flight in the back garden went great. Not much space, so just hovering. No sign of jello on the mobius footage. Need to get it out to fly it properly now!
All up weight is 940g with a 2200MAH battery. Short flight but it was hovering at about 9A on 3S and 65% throttle.
That's good use of a 3rd plate there! I'm half tempted to draw up a special underslung plate for cam and batt mounting. Make it like a skeleton to save weight. Did you say you were using elastic to hang it?
Quote from: Andy Sayle on December 27, 2014, 09:06:30 PM
That's good use of a 3rd plate there! I'm half tempted to draw up a special underslung plate for cam and batt mounting. Make it like a skeleton to save weight. Did you say you were using elastic to hang it?
An underslung plate would be good. With the way the motors are mounted on this configuration there's more space below, away from the props.
I was going to use standoffs to secure it but then decided to try black 3mm elastic. It's called shock cord I think. I got it on eBay, a few quid for 5m. It's pretty sturdy. It also holds the battery securely in place.
On the 3rd pic you can see most easily where I've tied a knot in it then run it through the slot in the bottom plate down to the 3rd plate. It then runs across underneath and up to the other side. I've done that at the front and the back.
I've offset the 3rd plate backward as I want to try and fit a gimbal at some point. That will make space for it and will also be useful to be able to move the battery back a bit to balance it.
I've had a few flights with the 330LF LOS and FPV. It's great. ;D
I got everything working with the Vector and once I was confident that the loiter and RTH worked did some FPV flying.
2200MAH on 3S seems good to have a reasonable turn of speed. With a 3300MAH 4S is was a blast. Pulling about 23A on 4S it was climing at 10m/S. :o
I was getting flight time of 15.5 mins with the 4S with some zooming around. 10.5 mins on 2200MAH 3S, using 80% of battery capacity. Pleased with both of those results.
A couple of issues - still getting some jello on the video, so I need to balance the motors now too. Also the LEDs were impossible to see with the sun low in the sky. The distinctive shape was more useful for orientation.
I think it was one of the best days of FPV flying I've had. First time I'm run out of battery on the mobius and the ground station in one session!
The 330LF is great. Lots more to learn, but a great start.
Looks great! ;D
Some more mods to my 330LF.
I wanted to make it easy to have different cameras, gopro, mobius or a gimbal attached to the quad.
So I've bolted a gopro bracket to the bottom of the quad. I've an adapter for the mobius or can attach the gopro to it directly.
I used the bracket directly rather than the slide in bracket as it's lower profile and the thumb screw will work just as well to change the cameras.
I wanted some smarter legs for my quad and having looked around ordered fixed CF legs that were for a 450/550 sized quad. I also ordered some light tarot retracts to check them out too.
The retracts were 80g per leg, compared to 80g in total for the the other legs. I saved about 10g weight by cutting them down to size. I saved 40g by removing the legs I had made from HK nylon legs attached to the ends of the arms. +30g for the CF legs with much better ground clearance seemed fine to me.
The retracts would have been heavier and OTT. Though they had a couple of useful features. They folded flat and they were all the same dimensions as the the other CF legs I bought. I wanted to make the legs removable and using the parts from the retracts made an extra set of legs. That means I have a short pair for mobius / gopro then a longer pair to use with the gimbal.
To make the legs easily removable at the top of the leg, where there would have been two grub screws I put the grub screws in to mark the tube in the right place, then drilled a 2.5mm hole through the CF leg tube. I made a pin from some 2mm CF rod, with a clevice glued on one end and a loop of elastic to hold it in place.
One of the back plates from the retracts was put to use making the gimbal mount. I now have two retracts for the toolbox to think of some future use for.... :+
The legs work well and keep the quad stable and the camera well off the ground. They're easy to remove and replace too. :D
I wanted to find a way of adding a gimbal that would fit on the gopro bracket on my 330LF. I chose the Xaircraft Stella 2 axis gimbal as it's really light, 120g, including charging for charging for gopro and all the wires integrated inside, including AV out from the Gopro. It can be powered by up to 6S, which is helpful as I run the quad on 3S and 4S. My tarot 2D gimbal with no charging was 200g.
I used a cheap gopro frame mount and a CF plate from the back of one of the tarot retracts I'd bought. The standard fitting was useful to keep all the spacings right. At bit of careful drilling and bolting later it was all together. I still need to tidy up the plastic around the CF plate, it's longer than it needs to be at the moment.
The gimbal fits well under the quad, the camera will have a clear view forward and down and the 'long legs' keep it well off the ground. I think the thumb screw hand tightened will secure the gimbal well enough and hold it level.
I'm sure with 4S power the additional weight of the gimbal will not be a problem, possibly even 3S. I wanted a flexible quad that would pack down small and could do lots of things from straightforward FPV, HD recording and the option to carry a gimbal for better camera shots. So far it seems to be measuring up to all of that well.
Looking forward to the chance to fly it and see how it works. :D
That's looking great! I'd be keen to see some videos/photos of it in flight ;) As well as seeing how good footage you get from the gimbal mounted on it!
Andy
Quote from: Andy Sayle on January 06, 2015, 11:18:19 AM
That's looking great! I'd be keen to see some videos/photos of it in flight ;) As well as seeing how good footage you get from the gimbal mounted on it!
Andy
Thanks Andy, I'll get some pics and video up when there's some better weather for flying.
Been busy and not caught any good weather for flying but have made a few more mods to the 330LF so I thought I'd share them.
I've fitted the spare plate as battery holder properly now with standoffs so it looks a bit smarter. I've also extended the arms so they're now half way between 330 and 450 length arms. That means I can now run 9443 props without cutting them down.
I've got a set of DJI 9443 carbon reinforced props and have balanced them as well as the motors.
I've added a folding mount for the GPS puck too. It was a bit wobbly, but I put a piece of fuel hose round the stem under the screw that holds the mount upright. When screwed down that holds it in position well.
Another thing I've done is buy a cheap gimbal and with a few mods mounted it on the front of the quad. It's still got the anti vibration mount, not sure if that's necessary, but it should help cut down on jello.
It's attached to the go pro mount I mentioned in an earlier post, so it can be removed and other camera mounts fitted. It's wired through a camera switch so I can see through the gimbal mounted camera or the flight cam. The tilt on the camera is also connected so I can adjust that in flight.
It's not quite a disco pro, but it was much cheaper! :D
The gimbal works well and seems very steady when powered up. I'm looking forward to getting it out flying now!
That's cool! I'm looking forward to hearing the flight report!
Andy