Re: AquaMule and AquaRam 18650 lights
Hi David,
I am pretty much ignorant in regards to all of the 18650's out there and wasn't even aware that an 18650 came with a button top. The 18650's I have been using are the ones depicted in your link and they have no button top. I am using a thick sterling silver bead for anode contact and it stands above the contact ring to accommodate a flush anode contact on the battery. I should comment that one concern I do have is that if the anode contact on the battery were to be significantly concave, it might make contact with the PCB screw which would induce a direct short. Should anyone be using a battery or the light in an application where they feel this could come about, I would suggest putting some protective film over the screw. Actually I have considered using a good hard nail polish to paint over the exposed surface of the PCB to provide a protective mask over the circuit traces on my own lights. I haven't bothered to do so because I plan to keep the interior of the light free from any debris.
I should also mention that I am assembling these lights using Christo Lube MCG 111 grease. A fellow CPFer turned me on to this grease a couple years back as an alternative to the Krytox which he was unable to source in his country. He said it was similar in properties to the Krytox and I have found his claim to be valid. I've since noticed that with some quality UW camera housings I bought that they seem to be using this grease or a similar one provided for the silicone o-rings in the housing.
As for using these lights out of the water, I see no problem in doing so and I have. I have a titanium Luminox dive watch that I wear 24-7-365 and I think of the Aqua Lights in the same manner; if it's good enough to go with you under water, it's good enough to go with you anywhere and no worries. What I don't know is what kind of depth rating would be reasonable for these lights or what the external pressure, at depth, might do to the twisting ability and on-off or level change of the light. I am confident the light can hold up to pressures exceeding the human body but to date have no empirical data. A good argument can be made for a magnet and reed switch or hall effect switch to be used on a dive light but then this adds complexity as well as possibly parasitic drain; neither of which comply with my design goals.
These lights are heavy and could likely serve up a fair amount of abuse as well as take it. The AquaMule with AW cell weighs 7.2 oz and the Aqua Ram with AW cell weighs 6.8 oz. The difference being the amount of aluminum in the two. (evident in the cross section dwg of their respective heads above).
A final comment for this post is in regards to the battery spring. Initially I was using the same silver plated spring I used in the 27LT's but with feed back from Martin I looked into a softer spring and opted for the "D" size Lee Spring battery spring. The lower spring force allows for easier twisting of the head for level changing. A good smack straight on the tail of the light will also give you a level change as the battery momentarily compresses the spring and looses contact at the anode. I can't imagine this is great on the battery if done frequently but it does serve as an alternate level shift should the need arise. I found holding the light in a fist with the tail inside my hand and then slapping the bottom of my fist with the palm of the other hand will give me a light shift without hurting my hand.
Hi David,
I am pretty much ignorant in regards to all of the 18650's out there and wasn't even aware that an 18650 came with a button top. The 18650's I have been using are the ones depicted in your link and they have no button top. I am using a thick sterling silver bead for anode contact and it stands above the contact ring to accommodate a flush anode contact on the battery. I should comment that one concern I do have is that if the anode contact on the battery were to be significantly concave, it might make contact with the PCB screw which would induce a direct short. Should anyone be using a battery or the light in an application where they feel this could come about, I would suggest putting some protective film over the screw. Actually I have considered using a good hard nail polish to paint over the exposed surface of the PCB to provide a protective mask over the circuit traces on my own lights. I haven't bothered to do so because I plan to keep the interior of the light free from any debris.
I should also mention that I am assembling these lights using Christo Lube MCG 111 grease. A fellow CPFer turned me on to this grease a couple years back as an alternative to the Krytox which he was unable to source in his country. He said it was similar in properties to the Krytox and I have found his claim to be valid. I've since noticed that with some quality UW camera housings I bought that they seem to be using this grease or a similar one provided for the silicone o-rings in the housing.
As for using these lights out of the water, I see no problem in doing so and I have. I have a titanium Luminox dive watch that I wear 24-7-365 and I think of the Aqua Lights in the same manner; if it's good enough to go with you under water, it's good enough to go with you anywhere and no worries. What I don't know is what kind of depth rating would be reasonable for these lights or what the external pressure, at depth, might do to the twisting ability and on-off or level change of the light. I am confident the light can hold up to pressures exceeding the human body but to date have no empirical data. A good argument can be made for a magnet and reed switch or hall effect switch to be used on a dive light but then this adds complexity as well as possibly parasitic drain; neither of which comply with my design goals.
These lights are heavy and could likely serve up a fair amount of abuse as well as take it. The AquaMule with AW cell weighs 7.2 oz and the Aqua Ram with AW cell weighs 6.8 oz. The difference being the amount of aluminum in the two. (evident in the cross section dwg of their respective heads above).
A final comment for this post is in regards to the battery spring. Initially I was using the same silver plated spring I used in the 27LT's but with feed back from Martin I looked into a softer spring and opted for the "D" size Lee Spring battery spring. The lower spring force allows for easier twisting of the head for level changing. A good smack straight on the tail of the light will also give you a level change as the battery momentarily compresses the spring and looses contact at the anode. I can't imagine this is great on the battery if done frequently but it does serve as an alternate level shift should the need arise. I found holding the light in a fist with the tail inside my hand and then slapping the bottom of my fist with the palm of the other hand will give me a light shift without hurting my hand.
