Replacement MC-E LED head for Canister Divelight ...

[wquiles]

For this project I will be potting the hipCC using specialized two-part Electronic epoxy from Loctite:

First tie the wires so that they will point toward the center (they will be inside the Delrin body I made earlier):

Pot the circuit - wait to be cured 24 hours:

Once this is cured, I will keep updating the thread.

Will

 

[gwilki]

Lucca

Thanks for all your input and information. You're right about always disconnecting the battery during transport. I got lazy once and that's what started this whole thing. Although it was a stupid thing to do, it looks like it will turn out to be a blessing in disguise.

Packhorse: Thanks for the advice about using a reed switch. Will asked me how I wanted to go and I decided to stay mechanical this time. I figured to keep the mods to the case to a minimum, and I've had problems with reed switches fusing closed in some other applications, so I am wary of them. I respect your advice, though, and may well go that way in the future.

Will: It is looking great! All the attention to making sure there are no shorts and that everything is bullet proof is really impressive. Thanks much for opening up the switch protector. I'm sure it will be more using friendly now.

Grant

 

[wquiles]

Thank you Grant. By the way, here is the current draw from a 13V supply (more or less a fully charged 12 volt SLA battery under load):

With the power supply set to 12.0Volts, the draw is approx. 1.0 amps.

Will

 

[gwilki]

Forgive my ignorance, Will, but theoretically, does this mean that, with 14ah worth of battery power, the light will shine for 14 hours +/_? I assume, having said that, that at some point, the voltage has dropped below what the driver needs, yes?

 

[wquiles]

Grant,

There are several ways to make the calculation, and it depends on what assumptions we make about charged battery voltage vs. discharged battery voltage, etc.. When measuring the output of the battery (input to the driver), one must record both the voltage and current since I am using a current regulator for the LED, so as you lower the input voltage to the driver, the current draw will increase to maintain constant output to the LED.

I like calculating runtime using watts, which is more realistic:
Available watts = 12 volts * 14 AH = 168 watts
Watts for load (high battery voltage) = 12.99 * 0.93 = 12.08 watts
Watts for load (low battery voltage) = 11.99 * 1.0 = 11.99 watts
Average load power = 12.04 watts

Runtime = 168 / 12.04 = 13.96 hours

So your initial high level estimate is about right

However, note that the driver needs only about 0.5 volts or so higher than vf to work (being that this is a buck driver). So if we assume something like Vin = 4-5 volts minimum, the driver will suck the 12 battery dry if you let it. Best to either keep a log of the numbers of hours you are using the light, or re-charge every time after a dive - that way you will not over-discharge the battery.

The good thing is that at close to 14 hours, you can do a LOT of diving before having to recharge

I forgot to mention to you that the hipCC is protected against reverse polarity protection, so if the LED does not turn ON, check that the battery is wired properly.

 

[gwilki]

Thanks, Will. My practice to date has been to charge the batteries after each dive day, or if I'm diving over a weekend, at the end of the weekend. I have 2 sets of batteries, too, so I've never been out of juice when I've needed it. I have 2 backup lights using alkaline, but if I go onto them, I call the dive. So, I like to be sure my primary is going to be there all through the dive.

 

[wquiles]

Grant,

The head is now complete ...

First, although the Al spacer is a pressure fit to the reflector, I am still going to go the extra step and epoxy them both together:

then, before I epoxy the reflector/spacer assembly to the head, I will give the spacer a small bonus - glow in the dark powder:

That "ring" looks really cool:

now I epoxy the assembly to the head:

as the epoxy cures, some of it will move down, making a solid bead on the back of the spacer, making for a very strong hold:

Then I install the thick lens with the 2 o-rings - one seals the plastic lens, the other holds the lens in place. The manufacturer of these rates the head for 200 (20 ATM) meters (at that pressure, the lens deflection is less than 0.5 mm):

 

[wquiles]

For these photos I am using a 12V 10AH SLA battery to drive the head. Note that the Warm Tint of the MC-E LED that I selected shows "true" colors for the grass, leaves, etc.. The beam is not super narrow, but it has a very nice hotspot with useful sidedeam:

Here I am about 20 feet from the mail post:

here lighting about 10-15 feet in front of me:

here it is about 20 feet to the wall:

and after turning the head off, you still have that nice afterglow:

All I am waiting for now is the special sealant for Delrin that I ordered, to buy a few new SS screws, and do final assembly. Almost done

 

[gwilki]

Will: The green glow is a real kick. Tks. The beam pattern looks really good. I'm getting more and more anxious to try it under water.

 

[lucca brassi]

I must admit very , very nice clean job - profi tools :cool3: love that!

Nice buck driver ( I have looked if I recognize driver chip ; I'm working for myself to construct driver and LED pad on the AluPCB )

Someone says that MC-E Cree a more suitable for lens (but lens have 86%max efficiency ) because of 90°angle of LED substrate goblet (more concentrated focus to steridian angle ,.... and in the same way the P7 are better for reflector , because of 120°angle of LED substrate goblet , more light it is catched on mirror.

No matter how-very nice result.

BTW: Why plastic glow - don't understand that

2BTW I don't know glue for delrin , because of it surface structure (adhesion) , but if you properly treat surface ( patented by DuPont with plasm , (made micropores)) you can glue them actuly with normal epoxy 2 component glues )
adhesives-for-delrin.htm

One of the properties of POM that makes it difficult to bond to is its low surface energy

Be careful between the dynamic or static load of the joint.(some of our specialists in lab made some glue research and sometimes I learn from them something I can later use for myself ) Which part you will bond together ?

Best regards