Behold the Parthenon - 5 XR-E Lantern - Added "Beamshots"

Partly inspired by evan9162's hedgehog design i wanted to build myself a LED camping lantern with some muscle, so when the XR-E's were announced i started thinking and came up with this:











It uses 5pcs. P3 bin XR-E in series, 12V 7Ah SLA and a shark board with an external pot that will allow the current to be adjusted from 25mA - 1A

It is about 35cm high and 10cm square, the top and bottom HS plates are 10cm x 10cm x 10mm thick and have 32pcs 5mm thick x 7cm long copper pins press fitted in 7mm deep holes between them. the top aluminium cube holding the led's is 25mm square and 50mm long and is held tightly to the top HS ( with thermal grease inbetween ) with a brass M8 bolt. The bottom HS fits tightly into an aluminium hollow section 10cm square x 20cm long which houses the SLA and electronics. the hollowsection bottom is sealed by another 10cm square x 10mm thick aluminium plate which is rivited to the hollow section.

Heatsinking should not be a problem !!

There is an XR-E on each side of the cube as well as one on the top. I decided to put one on top because other camping lanterns tend to illuminate 360deg in the horizontal plane but only a small angle at the vertical plane which i do not like. thus by adding an led at the top i almost got 360deg illumination in both planes.
The cover/diffuser is a jam jar which i 'frosted' by sanding with an angle grinder. it is attached to the top HS with a lot of epoxy.

In theory it should run for a minimum 4 hours @ 1A drive and a maximum of about 200 hours @ 25mA drive and give between 800 and 40 lumens of output.

It took me 3 days ( on and off ) to build but unfortunately when i finished it and turned it on it only lasted for a few seconds as something went wrong with the shark and is no longer boosting ( i really wanted to take it camping with me too, in fact that's why i built it ).

Thanks for looking

P.S. if anyone has a spare shark board and some AA epoxy ( finished mine on this job )and can sell and ship them to me ASAP ( and is as curious as i am to see this thing in action ) i'm willing to pay extra please PM me as i really want to take it camping with me and they might be able to get here in time.

Re: Behold the Parthenon - 5 XR-E Lantern

Fantastic built-from-scratch lantern and very unique look. :goodjob:

Any future plans for adding fold out legs to the base for increased anti-tip stability?

I love that simple globe retention device.

Does anyone know what current drive level for the XR-E produces the highest lumens per watt figure?
Maybe around 80ma? That's the setting I'd want to be able to dial in on the fly with a great lantern like this.

Re: Behold the Parthenon - 5 XR-E Lantern

Neat design. The mid-mounted heatsink is interesting - should still provide good cooling ability.

Re: Behold the Parthenon - 5 XR-E Lantern

Nice idea. I hope you will get it working again soon

Will

Re: Behold the Parthenon - 5 XR-E Lantern

Neat! Good idea with the jar, but it is fragile. I would of built a cage for it with a carry handle, or used a plastic container jar (like something from a large opaque bottle like rubbing alcohol comes in, or a lab container/etc).

Are those 2 holes where the switch and dimmer knob go?

Re: Behold the Parthenon - 5 XR-E Lantern

lumenhound: Thanks. I tot of adding slide out legs which i might add but the heavy battery is at the bottom which provides stability.

evan9162: Thanks for starting the tot in my head with your beautiful creation. i guess it will cool it quite nicely as the rods will transfer the heat from the top HS to the bottom HS whilst being cooled themselves, the rods are 12mm apart so air should go through easily. they better do their job properly as assembling them was a nightmare

wquiles: Thanks, i really really hope so too

Isaac: the jar is made out of very thick glass and is not that fragile, i wanted it to be plastic too at first but could not find a suitable one. yep that's what those holes are there for, there is also one on the side for the charging socket.

Re: Behold the Parthenon - 5 XR-E Lantern

they better do their job properly as assembling them was a nightmare

Click to expand...

Heh - I know your pain. For the hedgehog, I cut and threaded the 48 aluminium rods, and drilled and tapped 48 holes in the heat sink base. I really don't remember how much time I spent on it.

Re: Behold the Parthenon - 5 XR-E Lantern

very cool! Wish I had access to a machine shop... (A hobby table and dremel barely count)

Re: Behold the Parthenon - 5 XR-E Lantern

you really do not need a machine shop to build this. all that is needed is a hacksaw, a drill, a soldering iron and a lot of time

Re: Behold the Parthenon - 5 XR-E Lantern

would anyone be so kind as to tell me how to build myself a dimmable boost driver similar to the shark with common components ? size is not a problem. as it dont seem like there are any spare sharks 'swimming' around.

Re: Behold the Parthenon - 5 XR-E Lantern

very awesome! Good idea with the jar!

Re: Behold the Parthenon - 5 XR-E Lantern

jar3ds: thanks

Re: Behold the Parthenon - 5 XR-E Lantern

ok the Shark won't make it to me in time.

SO if i add another led and wire them up in two paralell sets of three led's in series DD off the 12V SLA and add a 330 ohm 5W pot in series will i get the same results as with the shark ( only not regulated ) ?
Will the 5W pot be enough ?

Thanks

Re: Behold the Parthenon - 5 XR-E Lantern

The 5W pot will handle the power properly, but I would do the following:

1) Add 0.5 ohms or more to each string to balance current
2) Add 6 or more ohms in series with the pot - this will set the maximum current when the pot is turned down to 0 ohms. Otherwise, when the pot is turned down to 0, you're direct driving the LEDs from the battery with no resistance, and will likely destroy the LEDs.

Re: Behold the Parthenon - 5 XR-E Lantern

good points thanks

So I temporarily modified it with 2 paralell sets of 3 XR-E's in series DD off the 12V SLA and add a 330 ohm 5W pot in series so i can make it work. there is also a 1.5 ohm resistor connected to each set.
It worked I'm getting 1.1A to each set ( i did not add another resistor after the pot because i only had a 3.5ohm resistor and with it i was only getting 450mA on each set ) and i must say, this thing is awesome at full power.

At 10mA i'm getting 3 lux @ 1m but at 1.1A im getting 225 lux @ 1m.
with a 28Watt CF i get 160 lux @ 1m !! it however seems that the 28W CF is putting out a bit more light which could be because of the better colour rendition?

Anyway here are some "beamshots" :

28W CF


@10mA


@50mA


@100mA


@250mA


@400mA


@600mA


@800mA


@1.1A


The CF is ovearhead 5ft away from the wall. the Parthenon is at the level of the middle picture but 12ft away from the wall.

The level of lighting is the same evenly throughout the whole room which is what i intended it to do, 360deg allround even lighting...and bright too

Thanks for looking

I tested it in my camping trip last weekend and it's awesome, it lights up a big area at a good level.

That is too cool! I hope you get your Shark issues sorted out. :thumbsup:

-Allen

I recieved a new Shark last monday but did not have time to put it in the Parthenon. maybe this weekend.

Amonra...awesome build.

How did you prevent the Cree XRE from shorting out? I would have thought that if you mount an XRE directly onto a electrically conductive heat sink....the positive and negative contacts on the bottom of the LED would short. Obviously I'm wrong. Does the epoxy act as the insulating layer?