Mod: BMF SRK v2 Roche Edition (Rebuilt into triple XHP 35 HI)

Flashlight Modding and DIY Parts
1

This light has been rebuilt into a XHP 35 HI triple. See post #18.

I was offered a broken Roche M170 for shipping costs as a modding host, and couldn’t turn it down (I did initially because I have so many hosts, but I didn’t know what kind of light this was). It’s been in my desk for quite some time now but I have had plans for it as soon as it was on the way. The plans where to combine the dual switch functionality of my firmware in this light: Mod/Driver: ZY-T08 series conversion, MT-G2. with a SRK style light like my M6: Mod: My SupFire M6 "BMF" edition (new beamshots in OP). and build a triple XHP70.

I started by redesigned the M6 driver to use the ATtiny84 and have exact same pin configuration as the ZY-T08, making the firmware fully compatible with only very minor changes. I’ve learned a few things on the way and changed a few other things too. I ditched springs on the driver side, went with bare copper and put on solder blobs instead. All I had to do was file them down a little. I kept the original M6 size as I have a two more M6 hosts, I just had to file it down to fit nicely into the M170. The driver provides a theoretical current of just over 5A per LED on max boost:

In with the XHP70 LEDs:

The E-switch was broken on this light, but I could use the contact board and solder on one I had laying around:

The battery contact plate needed some work, but was easily done:

To make a dual switch light I had to add a mechanical switch, so I filed down, cut and soldered on a 10A Judco switch. I made a pretty ugly job of the switch as it took a few goes, but it’ll do for testing the light. I’ll be replacing the switch later, would be a shame to have such an ugly switch on a nice looking light like this one.

Screwed the back plate on, but will be making a quick release system without screws as I did on the M6. Right now I just wanted to test the light out, so the screws went in.

The tail-cap needed a hole for the Judco switch. Once again, a darn ugly job on that switch (I deserve any crap you wanna give me) so it’ll have to be replaced later:

I had a rubber switch cover from an old headlamp laying around. Not my final choice, but good enough for testing. It needed just a little bit of glue to stick:

Then the light was ready to fire up. Still working on the firmware, but the nice thing is that I’m working on the firmware for two lights at the same time now as the ZY-T08 board is compatible. Still got a few things to go, like fine tuning the smooth seamless level adjusting and temperature control, but it’s operational… and pretty darn bright on max boost.

So many thanks to the donor for making this light possible!

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Am I happy with this light? Well, I use my M6 for photography in mines and such, and the triple MT-G2 beam in the M6 is much more suitable than the beam of this light with triple XHP70s. This beam is much for spot and it also suffers from the XHP70 doughnut ring:

Beamshot unedited. The doughnut hole doesn’t show much in this photo but it’s pretty noticeable to the eye on a white wall.

Edited beamshot to highlight the doughnut ring:

So I don’t know what I’ll do with this light once I’m done with it. I either do something about the doughnut hole, like Old-lumens trick with spraying on transparent paint or perhaps using a diffuser of some sort. Or maybe replace the XHP70s with MT-G2s but I think the beam will still be too tight for my intended use… Or keep it because it’s the brightest light I have so far… or maybe I’ll end up selling it once it’s done? I really don’t know yet. Any tips on the doughnut hole? Preferably reversible changes that don’t swallow up too much light.

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Looks pretty nice… you tend to do fairly exotic builds. :slight_smile:

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As always you set the benchmark of what can be done in the big LED soupcan light section.

Slicing the LEDs visually reduces the donut hole, but it doesn't eliminate it. I know that in a few lights I've done it took it from unacceptable to acceptable, but not great.

Unfortunately the XHP70s suffer badly from this and just don't produce a nice beam in most flashlight reflectors; the reason for this is obvious: the most focused part of the LED die produces no light, and that's where your eyes expects it to be the brightest. I know they're all the rage right now but I'll take an MT-G2 any day. I can barely see the difference between 4000 and 4500 lumens--or even 4000 and 5000 lumens, but I can easily see a huge hole in the middle of the beam.

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Nice job Mike. It’s neat how you can put lights like this (and many others) together without the need to rely on others for parts like drivers and firmware. What a great quality to have!!

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Thanks :slight_smile:

Yeah, I was kind of expecting the doughnut hole, but I still had to build a XHP70 triple. I got caught up in the hype over these LEDs and ordered three, initially for one of the M6 hosts I bought from you but they ended up in this light. I’ll admit I was hoping it wouldn’t be this bad though, so I might have a go at slicing. And the tint is no match for the MT-G2, but wasn’t expecting that either. I knew I’d prefer MT-G2s over XHP70s but this was a build I had to do.

As this a “high end” light I might just stick MT-G2s in it, but as mentioned I think the beam will still be a little too tight for photography. Decisions decisions…

Thanks. What started it all was me loosing the driver for my M6 that I had mucked up and sent to RMM. I just thought that if I design the driver myself I’ll have full control and won’t have to send them anywhere again. It’s liberating :slight_smile:

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If it will drop in, you might want to test the M6 reflector with the XHP70’s. Those round reflectors might be more forgiving. There are also a decent selection of reflectors for XHP70 on the ledil site.

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You could try this:

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Nice salvage job on the Roche, Mike!

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DBCStm already built an M6 with XHP70s and the stock M6 reflector...he said that there was still a donut hole.

Did you take any measurements to see how the sand job affected the output?

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I’ll probably switch the XHP70s over to an M6 and install MT-G2s in this one as it’s a light that deserves a nicer tint and beam profile.

Huh! I was totally unaware of that site (or seen it and forgot about it). Useful for many projects. Thanks!

As I’ll probably move the XHP70s into an M6 I will be willing to give it a go if the M6 XHP70 donut ring is too bad for my taste.

Thanks. Got more salvage hosts to work on, but this one is the nicest.

I hope that the M6 donut hole isn’t as bad, the Roche reflector is about twice the depth. In any case I won’t mind doing stuff to the M6 or XHP70 LEDs. Old-lumens sprayed on some stuff to emulate a sort of orange peal effect, maybe this stuff could work on the M6 reflector? I won’t try anything like that on the Roche reflector though.

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Sorry to resurrect but as my m170 is still in transit, did you have to enlarge the reflector openings Mike C?

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No worries. I’m not sure as I don’t remember, but I don’t think I needed to drill out the holes on this one. I wouldn’t bet a lot of cash on it though, was a while ago and I’ve done a fare share of drilling since.

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If you want to get rid of the donut hole, you need to break out the 3M pads and frost your domes like KawiBoy1428 did.
https://budgetlightforum.com/t/-/34589?page=18#comment-844986

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Very few mods on the M170... Fairly simple to work on like an SRK? Did you mess around with the stock driver at all?

How does it handle the heat of the XHP70s?

What do you think of the build quality of the M170?

I don't have a can sized triple thrower, XPL HI with a DD fet might be a fun mod... :)

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That looks nice mod. Do you have a short cut link to the process used? I’m not quite sure I will do it if it’s a lot of work as I might end up installing MT-G2s for the nicer tint. I also have some DC-Fix that I got to diffuse the XHP70s but I have yet to test it.

I didn’t find the M170 to be problematic and I really like the build quality of the M170 host, I’d gladly use them for all SRK style builds if I could get the hosts cheap. The only other SRK style light I’ve worked on is the Supfire M6 though, so not a lot of experience on different SRK style lights. I didn’t mess around with the stock driver at all as the light was donated to me because the driver was faulty. Even if it was working I wouldn’t have used it as I really wanted to use my own SRK style driver in it.

It handles the heat quite well. It gets too hot to hold comfortably after around 1 min and 30 to 45 sek when running the three XPH70s at about 5 amps a piece. It is such a nice host I think it deserves the nicer MT-G2 tint, but I haven’t really made up my mind about that yet.

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Nice mod Mike C. :)

Very useful info too as usual in all your build threads.

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It’s time to dust of my modded Roche M170 with XHP70s and do something else with it.

I never liked the XHP70’s tint or donut hole, and never bothered putting MT-G2s in it because the deep reflector makes it a little too throwy to be of use for my underground photography, so I never really used it. As it is rather throwy I thought I’d go with the flow and ordered some XHP35 HIs for it but I didn’t have a 4S driver for it at the time. As I’ve been busy with other drivers it’s just been laying around collecting dust… until now.

Here’s my new SRK style driver:

I made it both 2S2P and 4S compatible. Only battery pads + and - are “live” the other two are isolated and are to be connected by soldering wires. Here I soldered a wire between pad 2 and 3 making is 4S. To make it 2S2P I need a wire between 2 and +, and one between 3 and -. The only hardware difference is a single resistor.

The driver is a fully adjustable constant current without PWM from about 40mA up to about 8.4 amps. For low moonlight modes I use 10 bit PWM so it can go really low. I’m no electronics guy so I need easy use regulators for constant current, so I went with 12 x CAT4104s. One is adjusted with a 256 step digipot from 40mA to 0.7A, the other 11 have fixed resistors at 0.7 amps each and any number of them can be turned on or off. The 4104s may not be the best choice, but they are easy to use for an electronics noob like myself, and are very small considering they can handle 0.7 amps each. They work fine from 2.7V (haven’t tested lower) up to 25V so they are rather flexible too, but they do come with a price tag. It’s all just part of the hobby though, I’ve just wanted to make my own fully adjustable constant current driver for my SRK lights for quite some time now, and the 4104s do the job. I stuck an old re-used FET on it for testing, but won’t be using it for the XHP35 HIs, they have been reported to sometimes die above 3 amps.

I didn’t have any centering rings that work with the reflector holes, so the LEDs aren’t very well centered. The beam looks OK to me on a white wall, but I’m no beam profile snob.

I got rid of that horrible side switch I used in my original build and replaced it with my favorite lighted switch. It was a little too bright at 12V with included resistor, so I added a larger resistor to damped it a bit. I really like the protruding switches but it didn’t fit so I had to drill out the hole a bit. I made a little bit of a mess so I covered the mess up a little with a rubber washer :blush:
Firmware flashing the 1634 is done by my usual acupuncture style method:

So here it is in it’s new configuration… A fully adjustable constant current driven triple XHP 35 HI SRK style light… For a SRK style light it is really thowy now. Not sure I’ll find any use for it, but it was just something I had to do.

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I love your black magic Mike. thanks for posting it up. :+1:

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Nothing like the magic I’ve seen you do, but thanks :slight_smile: