I just finished a build for Tbxxx and he suggested I do a write-up here for you guys in case there are others looking for a high output zoomie that doesn’t give you blisters after a couple of minutes on high.
The Components:
- MT-G2 Q0 5000k on 20mm Noctigon
- MTN-17DD board from RMM, I reflowed the components onto it, including a zener mod and guppydrv flashed MCU
- Omten 1217 in the tail
- Tailcap switch board from 1504 sanded down to fit smaller switch cavity of 1405, added solder to the traces to improve heat and electrical transfer
- Brass pill from a Uniquefire 1504 host, machined to improve emission angle in flood, to add Ø20.6mm riser, and center MCPCB
- Machined aluminum collar to go around the driver area
- Ø20.6mmx1.5mm machined brass riser for MCPCB to pill connection
- 18ga wires for driver to MCPCB, + spring jumper, and -spring jumper
- Heavy application of Noalox to pill threads to improve heat transfer to body tube
- Heavy application of Nyogel to body tube to head threads to improve heat transfer and smoothness of zooming
- O-ring under the flange of the pill to raise the pill for improved flood and slight defocus in zoom to minimize honeycomb (gained 200 lumens from this in flood)
- High temp flat black paint
- Arctic Silver thermal adhesive to permanently bond the aluminum ring
Tbxxx has bought two other lights from me and was looking for another light to add to his collection in the form of a bright and floody zooming light. I made some initial recommendations to him on building one, and he decided that he wanted me to put it together for him as he had already burned up 2 MT-G2’s in the pursuit of this type of build, and was impressed with the build quality on the two lights he already got from me. The goal was a light that could handle more than 2-3 minutes on high without fear of catastrophic failure from the heat. I’ve done a similar build in a Jax Z1 so I knew that thermally that light topped out at around 2-3 minutes max before it was blisteringly hot. With that in mind I had suggested to him using the 1405 as a host because of its higher mass in the head, and the easy ability to add a few upgrades to the thermal path. This light is the result. I tested it at full power to the 4 minute mark to make sure it would handle it without issue and it did brilliantly. It got very hot, but no hotter than the Jax Z1 was around the 2-2.5 minute mark. After that stress test I set the turbo timer to a conservative setting of 2:15 so it can basically run indefinitely if someone sets it down and forgets about it till the batteries are drained without fear of catastrophe.
The final measurements were
Lumens in pipe:
Startup: 2500
30 Sec: 2400
90 Sec: 2250
Candelas: 82kcd
Measured current through homemade shunt wire: 8.8 amps with 2 fully charged Efest Purple 3500mAh 26650’s
Going off of DJozz’s test of the MT-G2 this means there is about 28% losses in flood mode in this 1405. I’m assuming 5-10% of that is the lens and the rest is lost light that doesn’t hit the lens. The o-ring I added under the pill brought the output up about 200 lumens across the board by catching more of the lost sidespill. I would consider adding more to improve it further, but eventually you start to severely hamper the thermal path, so this is a good compromise. The o-ring also slightly defocused the honeycomb effect in zoom mode. It’s visible at less than 100ft, but beyond that it’s very hard to notice. Sorry, no good beamshots, maybe Tbxxx will share some when he gets the light on Friday.
Those of you with sharp eyes will notice the blue vise, I picked it up at Harbor Freight this week after seeing another member talking about it. It freaking rocks! My old tabletop swivel vise had just about died from the heat melting the rubber jaws, this thing is going to work nicely.
I have been using VHT caliper paint and I like it a lot. It needs to go into the oven for an hour at 200 degrees, but it's hard as nails when it comes out.
I’m good to 400F. If I used C series I’d be good to 1700F