DIY Tail Night Blades

[Finless]

BTW they now make rechargeable versions of those small hearing aid or watch batteries!

http://shopping.microbattery.com/s.n...ategory.910/.f

Bob

[Ecklund1]

@Jeff - How did you get the wires to the LEDs? Foil on the other side? Really long drill bit?

@Bob - Nice find! (BTW, Why are you up on "hearing aid" batteries?! )

[flyinfool]

Originally Posted by Ecklund1

@Jeff - How did you get the wires to the LEDs? Foil on the other side? Really long drill bit?

Yup, a long drill bit. I used magnet wires that have a solder thru insulation.

Bob - The biggest of those rechargeables are still smaller than my holder made for a 1025 cell, and I am not sure of what is needed for a charger. Those are 3V not the 3.7v like our LI packs with very low charge current needed.
Do you have any more info on the actual care and feeding of those cells?

[flyinfool]

Bob
OK I found the data sheets.
The max discharge is 50uA.
Their over discharge graph at 170uA will cause an 80% capacity loss in just a few cycles. My 2 LEDs will pull 40mA which is 40,000uA or 800 times the max rating.
I think that the rechargeables would "taco your pack" pretty quick dude.

Granted, the cells that I am using are being pulled on a lot harder than designed for, but I plan to toss them after an hour.

[Finless]

Check here.... these recharge-ables are just coming out.
I tore a set of dead Align night blades apart and found a watch battery that was lion and said rechargeable... So you could use the Align blade charger too!

http://shopping.microbattery.com/Rec...eries-Chargers

http://shopping.microbattery.com/Pow...category=15559



Bob

[flyinfool]

Just an update on the button cell rechargeable.
They are getting better but are still not up to the performance that we need to light up 1 or 2 LEDs.

[kavic5150]

Been looking everywhere for actual Li-ion rechargeable button cells. Already ordered a half dozen of the 2032 size from ebay. Smallest ones I could find anywhere. They say 50ma but I dont know how to test that. They are 20mm x 3.2mm and 4.1v fully charged.

I checked those links bob provided, they are all NiMH cells with a 1.2v rating.

There are 10 and 20ma single cells available from domestic suppliers, you just gotta hunt for them.

I'm planning to try making a set for the 550 but not for any of the smaller birds. Heres a few pics I found of someone elses night tail blades:



I suggest anyone that wants to try these should have the lipo placed with its leads pointing toward the blade grips. I've heard that the polymer part of the cells can actually leak if they are mounted wrong.

[automandan]

Jeff - I've got another idea on how to mount the batteries that I would like to experiment with. Could you clue me in as to........

1) where you got the holder for the 1025 cell,
2) what size LED's you used, and
3) how you attached the LED's?

Thanks!
Dan

[jackheli]

kavic5150

I tried that exact setup you posted and two things were bad:

1-The connector at the back gets crushed when the blades fold back
2-The battery gets thrown off when the tail spins at 16k rpm.

That is no good...

[flyinfool]

Originally Posted by jackheli

kavic5150

I tried that exact setup you posted and two things were bad:

1-The connector at the back gets crushed when the blades fold back
2-The battery gets thrown off when the tail spins at 16k rpm.

That is no good...

What kind of heli has a 16K tail rpm?

Originally Posted by automandan

Jeff - I've got another idea on how to mount the batteries that I would like to experiment with. Could you clue me in as to........

1) where you got the holder for the 1025 cell,
2) what size LED's you used, and
3) how you attached the LED's?

Thanks!
Dan

1) Digi-Key BH401-ND
2) 0805 I used red so that no resistor is required with a single cell. other colors need more voltage than the one 1025 cell can give.
3) Soldered to the magnet wire and then epoxied with a clear epoxy to both hold them on and make them more aerodynamic.

[jackheli]

Woops... 6k

Was the slowest I could run it that it would still hold the tail in place.

[automandan]

Thanks Jeff - much appreciated!

[HankAz]

These flat batteries might work. I seen them in another post.

http://www.powerstream.com/thin-lithium-ion.htm

[Jherison]

Wrong topic, sorry!

[Airworks]

what about using replaceable (non rechargable )watch batteries???? maybe even be able to inlay them in to a carbon blade in teh trailing edge???