Klem
Enlightened
Extending AJ,s questions on another thread here are a couple of 50mm Maglite mods.
Both use the Bill Bowen toggle circuit; one uses reed switching while the other uses a piezo. The aim is to extend the 50mm diameter of the Maglite head for the full length of the torch. The generous 50mm of body space now allows for battery packs like 4*18650 Li-ion in a 2S2P configuration, 7.4V, 5Ah. I find the 50mm diameter is fine for gripping underwater and fits nicely in a BC pouch or on the arm (no need for cable and canister). Both negatively buoyant, without needing to add weight.
The left uses a toggle circuit with piezo, 50mm piping and O ring end cap. The right uses a toggle circuit with array of 4 reed switches, 50mm piping with central O ring join.
The 3 Cree XR-E's are a drop-in by Terralux, however from reading this forum I have no doubt you guys can improve on that...so I'll stick to what I can contribute... the concept and build.
Take the head of a Maglite and lathe the back half of it to press-fit into the internal diameter of 50mm pipe. The OD of 50mm pressure pipe will be exactly the OD of a Maglite head (if you live in 'Down Under' it will be). Note the couple of deeper channels lathed into it to prevent glue starvation.
One of the lenses is 4mm glass, while the other is 5mm Perspex. Both lenses are glued into the bezel with epoxy putty (Aqua Knead-it, by Selleys). Both Maglite head O rings are discarded and the bezel-to-head seal is from a tube of silicone sealant (Silastic). You don't need to open this on a regular basis, if at all.
The black end-cap torch is pretty straight forward so I won't dwell on that. The middle-seal torch has a sealed forward section, which minimizes damage if it floods. It is also more compact.
Shown below is the first build of the middle-sealing design. The 7.4V Li-ion pack is a perfect fit in the back end which is also great for minimizing buoyancy. The two plugs; The Deans plug (red one) is for normal charging and the JST plug (white one) is for balance charging.
The reed switches were originally glued to that expanding collar, which you can see just fits just inside the front join. All was well until some clumsy oaf (me) dropped the torch on the deck and the shock cracked one of the reeds to permanently on...which got me thinking as to how to bomb-proof the design.
The later improved build (below) uses 4 reed switches in a square array protected in foam (the yellow cross), and away from any transmitted shock coming through the body. The 4 reeds are at cardinal points which allows the magnet to come at the torch from any direction.
The front half of the torch is sealed with a waterproof bulkhead (with the humidity inside purged first with a hairdryer). Brass bolts are the interface contacts. Both torches use 4*18650 Li-ion packs, 5Ah 7.4V. Note the protection circuit running down the side in the cavity between the batteries.
Switching the reed-switch version is via a rare-earth magnet sewn into a hollow strip of some climbing tape, which also acts as the lanyard. The magnet is sewn at exactly the length for when pulled tight along the outside. Makes switching in murky conditions a lot easier. The lanyard points are 6mm stainless U bolts with washers on the inside to spread the load. Normally used for rope clamping, and found in your local hardware store. The right hand photo is water testing the bulkhead in a tub for a few days. Sometimes I go down to the local bridge and lower torches on rope into the river to get a bit of pressure on them. The fishermen must think I'm bonkers.
I also made an armband for hands-free, fits both torches; made out of some old wet-suit material and 20 minutes with a hand-stitcher. Slips on and off, both above and below the water. No offence to anyone but I find armbands more 'hands-free' than the Goodman design, especially when grabbing things like rope or ladders....Or crays!
Safe diving, and if you're good Uncle Klem will give you his famous recipe for pan-fried crays with garlic butter, pepper and lime juice!
Both use the Bill Bowen toggle circuit; one uses reed switching while the other uses a piezo. The aim is to extend the 50mm diameter of the Maglite head for the full length of the torch. The generous 50mm of body space now allows for battery packs like 4*18650 Li-ion in a 2S2P configuration, 7.4V, 5Ah. I find the 50mm diameter is fine for gripping underwater and fits nicely in a BC pouch or on the arm (no need for cable and canister). Both negatively buoyant, without needing to add weight.
The left uses a toggle circuit with piezo, 50mm piping and O ring end cap. The right uses a toggle circuit with array of 4 reed switches, 50mm piping with central O ring join.
The 3 Cree XR-E's are a drop-in by Terralux, however from reading this forum I have no doubt you guys can improve on that...so I'll stick to what I can contribute... the concept and build.
Take the head of a Maglite and lathe the back half of it to press-fit into the internal diameter of 50mm pipe. The OD of 50mm pressure pipe will be exactly the OD of a Maglite head (if you live in 'Down Under' it will be). Note the couple of deeper channels lathed into it to prevent glue starvation.
One of the lenses is 4mm glass, while the other is 5mm Perspex. Both lenses are glued into the bezel with epoxy putty (Aqua Knead-it, by Selleys). Both Maglite head O rings are discarded and the bezel-to-head seal is from a tube of silicone sealant (Silastic). You don't need to open this on a regular basis, if at all.
The black end-cap torch is pretty straight forward so I won't dwell on that. The middle-seal torch has a sealed forward section, which minimizes damage if it floods. It is also more compact.
Shown below is the first build of the middle-sealing design. The 7.4V Li-ion pack is a perfect fit in the back end which is also great for minimizing buoyancy. The two plugs; The Deans plug (red one) is for normal charging and the JST plug (white one) is for balance charging.
The reed switches were originally glued to that expanding collar, which you can see just fits just inside the front join. All was well until some clumsy oaf (me) dropped the torch on the deck and the shock cracked one of the reeds to permanently on...which got me thinking as to how to bomb-proof the design.
The later improved build (below) uses 4 reed switches in a square array protected in foam (the yellow cross), and away from any transmitted shock coming through the body. The 4 reeds are at cardinal points which allows the magnet to come at the torch from any direction.
The front half of the torch is sealed with a waterproof bulkhead (with the humidity inside purged first with a hairdryer). Brass bolts are the interface contacts. Both torches use 4*18650 Li-ion packs, 5Ah 7.4V. Note the protection circuit running down the side in the cavity between the batteries.
Switching the reed-switch version is via a rare-earth magnet sewn into a hollow strip of some climbing tape, which also acts as the lanyard. The magnet is sewn at exactly the length for when pulled tight along the outside. Makes switching in murky conditions a lot easier. The lanyard points are 6mm stainless U bolts with washers on the inside to spread the load. Normally used for rope clamping, and found in your local hardware store. The right hand photo is water testing the bulkhead in a tub for a few days. Sometimes I go down to the local bridge and lower torches on rope into the river to get a bit of pressure on them. The fishermen must think I'm bonkers.
I also made an armband for hands-free, fits both torches; made out of some old wet-suit material and 20 minutes with a hand-stitcher. Slips on and off, both above and below the water. No offence to anyone but I find armbands more 'hands-free' than the Goodman design, especially when grabbing things like rope or ladders....Or crays!
Safe diving, and if you're good Uncle Klem will give you his famous recipe for pan-fried crays with garlic butter, pepper and lime juice!
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