It's that time of year again... Trex 250 night fly projecct

[naga]

That is truly amazing! (Standing Ovation)

You are quite right about it looking like the USS Enterprise, it is all in those tail booms. I love the way the green upper lights fades into the red lower ones!

You must be feeling really pleased. But I am curious about the ability to dim the lights; you have a spare channel to control that from the TX?

[myxiplx]

Yeah, a spare channel on the TX can be used to drive an old *brushed* ESC, and that can turn the LEDs on and also act as a dimmer.

I've got a lightweight ESC, but haven't got it running yet. Might have a play with that for version 2 of the chassis lights.

[gstoneberg]

That looks very nice, good work! I'm really impressed with the blade lights. I had started copying your mcpx blade design when i discovered the perfectregulators lights and went the easy way. Those are super! The tail lights are very interesting. They seem to stay in place nicely. Nice flying too.

[myxiplx]

One of the 250 guys asked how I made this, so I'm going to try to do a bit of a write up. I did take a few pictures during the build, but probably not as many as I really need. If anybody has any questions, just ask and I'll try to answer.

Firstly, the absolute bible for building your own blades is this post on Helifreak. I learnt everything I know about soldering night blades from watching these videos, and they really are essential when it comes to working with such tiny components:
https://www.helifreak.com/showpost.p...4&postcount=11

The basic idea for these blades is the same as the one I used on my mCPX BL. I just put the LEDs and bare minimum of wiring on the blades, and put a battery socket on the head. My mCPX BL thread doesn't really detail the build, but does have a few useful pictures:
https://www.helifreak.com/showthread.php?t=567735

Part 1 - The Blades
The basic steps to make the blades are exactly as shown in the videos above. The parts I use are:

• 0805 SMD LEDs
• 0805 SMD Resistors
• 5mm copper tape
• Automotive clear spray
• 30AWG solid core kynar wire

I bought all of that off eBay, in the UK Bright Components are great for LEDs and resistors. You'll need to work out what resistors you need, but there are a ton of online calculators, just feed in the max battery voltage (4.2V for a Lipo), the LED forward voltage (typically 2-3V depending on the colour), and the max current you want through the LEDs (typically 20-30mA).

The build steps are:

• On carbon blades (which are conductive on the edge), roughen with 600 grit wet & dry, and spray with automotive clear to insulate them
• Find and mark the centreline of the blades
  
• Mark where you want the LEDs (they need to be evenly balanced over the two blades)
• Slice the copper tape into 1.25mm strips
  
• Solder the LEDs and resistors together in pairs (Kapton tape!! Awesome stuff)
  
• Stick two runs of tape on the blades (just far enough apart for the LED+resistor)
  
• I usually write + and - on the blade at this point so I know which way round everything needs to go
• Add a little solder flux to the copper tape where the LED will go
• 'stick' the LED+resistor in place using the flux
• Solder the LED+resistor on (be quick so you don't apply too much heat to the blade)
  
• Once done, test the LEDs and solder two short lengths of wire to the blade
  

[myxiplx]

Part 2 - The head

The head is even easier. I use some round button cell LiPos, and found a great little holder that I just bolt on to the head of the heli. The parts are just:

• CR2032 battery holder
• Slightly longer head screw

The battery holder I'm using was this one:
http://www.ebay.co.uk/itm/2-x-Best-Q...item2592425a3d

And to build it:

• Find the centrepoint of the battery holder
• Carefully drill a 1.5mm hole
• Solder the blade wires to it
  
• Test
• Bolt to heli :-)

[myxiplx]

Part 3 - the body

The body is a little different. There aren't any normal guides for this as it's an idea I've adopted from a video I saw online. The normal approach would be to mount LEDs on the body of the helicopter, and run copper wire or thin wires as needed.

Instead I've created a pair of carbon fibre 'chopsticks' which thread through the body of the machine and plug into the 5.5V from the FBL controller to light the tail and canopy. Once you slide the chopsticks through the side frames and secure them to the base with a single cable tie they wedge in very snugly.

Testing the chopstick idea:


Parts needed:

• 2mm LEDs
• Resistor (I used 0805 SMDs but standard resistors would be fine)
• 30awg Kynar coated solid core wire
• Servo plug, or some means to connect power
• Carbon Fibre Tube 2.5X1.5mm

For the build I don't have many good photos I'm afraid. I do have plans for a mk.2 and I'll document that a little more carefully.

• Cut 2.5mm carbon tubes to length
• Seal the ends with CA
• Use some cotton thread and CA to glue one end of the two rods together
• Once the CA sets, thread two 30awg wires through each tube
  
• Solder LEDs to each end (my setup needs two LEDs wired in series with a 47ohm resistor)
  
• Add a servo plug for power
• Voila, one set of lit chopsticks :-)
  

[myxiplx]

I might have to update the build notes. I had a rethink last night and just created version 2 of the chopsticks.

The rear LEDs were a bit bright when pointing straight at you, and while hunting for a solution I stumbled on some pink fuel tube for my nitro. That plus a couple of beads from my little girls craft set created the perfect ends. Easier to see at night, no glare, and it looks even more like the USS Enterprise now :-)



These are much more neatly built, plug in separately so they are easier to attach, and also fit in my carry case. I can fit everything I need for five night flights in here now:



Love it :-)

[naga]

Very 'Enterprising" indeed (cough)!

Looks very cool. I am very much enjoying this build.

Unfortunately, my garden is too small for a heli of this size especially with next door's apple tree overhanging, so I won't be buying this one from you when you are ready to upgrade but I am enjoying the mCPX BL!

[Raptorapture]

Watching the Starship Enterprise doing backflips was too hilarious. Great idea. I hope someday to have a similar night ship. Looks like the tail lighting really helps with orientation.

[myxiplx]

I'm loving this for orientations. I had a night fly mCPX BL before, and while it was good, you didn't always have a clear sight of the tail.

The original aim here was to light up the tail rotor from both sides. While that may still be possible with directional LEDs, I actually prefer the way this turned out. Having two lights that are offset from the boom means you can always see them, you never ever lose the tail.

And the dual colours on the main rotor really help with those orientations too. I remember now when I was learning, side orientations used to be tricky, and I actually started using the mCPX BL night lights during the day because it made those side on orientations so much clearer.

and the starship enterprise look is just a bonus, no way I'm changing this now :-)

[Raptorapture]

I also suffer a bit on side on orientations. I need to give a jiggle to find out if dipped a bit away or towards me. Of course that also helps get the correct direction of movement sorted as well if confused. I'm thinking to rig some minimal night gear to help with orientations near dusk as I end up flying quite often at that time. It's not dark but somehow everything becomes a single colour of grey. Even an hour before, the contrast may drop to almost nil and unless moving quickly, orientation becomes a challenge.

[myxiplx]

Yeah, as i was learning I found sideways on was tricky, and sometimes its an optical illusion, if your brain has it wrong, even a quick jiggle may not show enough for you to spot the mistake.

You won't regret adding some night blades. At dusk those thin rings of red or green on mine make it extremely obvious which way the disk is facing.

I deliberately mount my LEDs at the same positions above and below (but on opposite blades), so that as the disc tips one colour just gets replaced by the other, but any blades with different colours on the top and bottom would work fine.

[myxiplx]

Just adding another piccy to the build thread, I made a parallel charge board for the blade light batteries, and found some storage cases that are perfect for these little LiPos.

[Koopyetz]

Nice.

Would like to do this to my 250 but flying it where I live would probably flood the sheriff's office with calls about UFO sighting.

[myxiplx]

All the more reason to get started