Help modernizing SF M4

Hello, appreciate any help. I have a SF M4 I bought years ago and didn't use much. Incredible light, but just couldn't bring myself to run it on 4 primaries, especially with the short runtimes on the brighter bulb I wanted to use.

So now, many years later, I'd like to use the M4 components to build something cool. I'd like it to:

1. Use rechargeable batteries. I don't have any way to bore out the body, so I assume 2x17670 (LiIon or IMR) just fits as-is and is the way to go.

2. Be really bright. Duh. Note quite sure what this means, given the power source. Assume two protected LiIons, or IMRs if needed

3. Be more throwy and search-lighty than floody. It should lean more towards throw, but doesn't have to be uncompromising in that (I imagine it's not easy to make something like an SST-50 a perfect thrower, and that's fine)

4. Assume I have minimal to no do-it-yourself skills. I need to buy components I can slip in or screw on, or send it to someone who has a regular service to do this

5. Since I can buy a Thrunite Catapult for $150, and it seems to meet everything above, I'm hoping not to spend more than that on my revamped SF M4


Any advice appreciated, thanks in advance! I'm obviously favoring LEDs, which is why I posted this in the LED forums, but if there's some amazing incandescent bulb for the M4 I need to know about, please let me know.

Joe

If you just want a rechargeable M4 then the lumensfactory HO-M3T and a pair of aw 17670 cells (and a decent charger) will do nicely, and performs similarly to the stock light (using 4x 123 will blow that globe though, so it's rechargeable only)

The lumens factory P7 head is a nice upgrade too, around a hundred bucks, and will run from 9-12v so it will work fine on 3 or4 primarys, and 2 or 3 rechargeable, Mine is currently living on my M4 body, with 2x 17670

Nailbender, and possibly a few others build tower modules too, these are basically replacements for the lamp assembly in the turbohead and you can specify what you want it to do (multimode, differing voltages etc)


There is probably a few options I have missed, but I use both options 1 and 2, switching when the mood strikes.

Hope this helps

Thanks, I'd already found the lumens factory ho m3t, but the short 30min runtime on 2x17670 gave me pause. I think it's a fine solution, but I was hoping I could get similar performance at great runtime/efficiency using an LED. If not, ho m3t is great.

I hadn't noticed the p7 head, that looks great, and was the kind of solution I was expecting to run into. It looks like it could conceiveably double the output of the HO M3T, though I imagine on only 2x17670 it doesn't reach that level. Any thoughts on runtime on 2x17670?

What are your reasons for switching back and forth between these solutions? Does one particular excel at something in particular over the other?

I'll start hunting around for tower module replacements and other replacement heads. I remember seeing at least one other M-series head replacement, but I can't remember from where

Joe;

It turns out we work at the same place. A couple of years ago we met and you helped me out with another subject from another forum in which we have a mutual interest.

I also have an M4 (and M3 and M6) which I've modernized with rechargeables and both incan and LED solutions.

The problem with LEDs in Millenium turboheads is that there's really not enough heatsinking capability to run high-output solutions. I had another forum member build me some medium output LED towers, and they work great. But they're not putting out the beautiful beam of an MN61.

Your best bet for a high output LED solution is to pick up a P7 turbohead made by Lumens Factory. I hear they're quite good for the money (~$100 from Lighthound) and get around the headsinking issue by just having a whole new head designed around an LED.

As for the issue of boring the light, your best bet is to send it out to moddoo and electronguru and have it professionally bored for about $45. The turnaround time is about a week. The capacity difference between 18650s and 17670s is just too large to ignore (2900ma vs. 1600ma).

All of this costs some reasonably serious money. Don't worry, though. You can easily sell the stock Surefire MN60 and MN61 lamps for about $10-15 each. If you decide to go with the lumensfactory P7 head, you can sell the KT4 turbohead you have for $100-$120. So this upgrade won't cost much out of pocket.

In the short term, though, you can pick up a pair of 17670s and a Lumens Factory 9v lamp for not much cash, and just check it out.

If you'd like to see some of the options I've talked about, I'd be happy to bring some in to work one day, so you can get a feel of what's out there before you drop the cash.

-John

Thanks John, that seems to make sense. Yes, would love to see the solutions you're using, thanks for the offer. Probably no getting around switching to 18650s I suppose... of course, that brings me back around to the Catapult v2 ... at the cost we're discussing, why not sell the whole damn M4 and spare lamps, buy the Catapult and still have some pocket change left over? Maybe the answer is that the M4 is just so damn well-built... and because being able to go back and forth between incandescent and LED options with both the stock M4 and the LF head might be nice...

Joe;

You've hit the nail on the head. The reason, in my view, that Surefires are worth the money is the ability to lego an infinite number of options together.

Depending on what you want to do with your M4, incan might be the way to go. Although runtime is sacrificed, the color rendition can't be beat. I'm a diehard LED guy, but lately I've been getting more and more into incans, primarily for the color rendition. One of my next purchases is going to be a high CRI RA clicky, just because I've gotten tired of staring at pale LED beams.

In the end, you might find that 30 minutes of runtime is enough for what you want to do, because you can just pop your Li-ions into the charger and top them off when you need it. Plus, you can easily get low output bulbs for longer, lower runtime.

I'll contact you offline and we can make arrangements to meet in person.

-John

I also have an M4 body with the Lumens Factory P7 3-mode head. Very nice if you ask me. I run 2x AW17670's and the current at the tail on high is around 1.4A. That should be an hour of runtime. On three AW cells it pulled 1.1A FWIW.

Great ... just to confirm, two protected 17670s? I'm about to pull the trigger on this setup

Joe;

Yes, two protected 17670s are the way to go. Make sure you get AW brand. In my experience, they're the best. I had a situation a while back where I accidentally caused an 18650 to dead short itself. Because it was an AW brand, the battery pressure relief kicked in, and the battery vented WITHOUT flame. I cannot tell you how happy I am to this day that I did not have an explosion with poisonous flame in my house!

If you don't already have a Li-ion charger, check out mdocod's thread in the batteries section. It has a lot of info on which cheap charger to get, and how to safely use them. Li-ions are great, safe, and easy to use, but you need to have respect for them.

-John

Yes, thanks, I've been using LiIons for a while and researching extensively. I have a Pila charger and will stick with it... from what I can tell that's still the favored charger, and the one that seems to best approximate a CC/CV with true termination -- though I still charge my batteries in a place where there aren't a lot of flammables around, and try to take them out of the charger as soon as the cycle is done

I think you would be more than happy with the Lumens Factory P7 head, it's plenty bright enough and has a VERY SMOOTH beam pattern (no donut hole at all). FWIW I didn't like twisting through modes and put a Z58 clicky tail on mine, worlds better.

Here is a link to a Tower Module for sale.. but you may want to find one that will run on primaries as well as rechargeables...

http://www.cpfmarketplace.com/mp/showthread.php?p=2547517

Gordon

That direct drive tower (looks like it is based on an AW turbo tower kit) probably can be re-worked by replacing the contact board with a real driver. An SOB1000 would give you a low power draw, but still reasonably bright MC-E driven at 250mA per die. It should work well with either 4x123A or 2x17670. 4x16340 exceeds the SOB's max input voltage spec of 16V and probably should be avoided.

If you want to drive the 4P MC-E harder, you can get up to an SOB1500 (nominally 375mA drive current per die). Or you can also re-wire the MC-E into 2S2P and use the SOB1000. That will give you 500mA per die.

I also notice that there doesn't seem to be a center spring soldered to the contact board. That might make electrical contact to the top button of the battery stack a bit tricky.

If it is an AW tower kit, It might be wise to check which tower focus (Seoul or Luxeon) was used. If Seoul, an MC-E needs to be raised higher to get it to the proper focus point when using a SureFire TH. IIRC, cpfmember removed some metal from the tower's flange, which effectively accomplishes the same thing as shimming up the MC-E.

An MC-E tower won't be a great thrower, if that is one desired goal. But if you drive it reasonably hard, it should throw well enough as well as provide a lot of lumens.

Another option is a nailbender XP-G tower, based on a Netkidz tower kit.

Those tower options look interesting also, Nailbender's XP-G has a single level version with a wide range of input voltage. I imagine running that in the stock M4 head would yield a tighter beam but lower lumens than the P7 replacement head (both on 17670s)...

JT, sorry to go OT, but did you know that you're #20?
Only ~10 or so CPF'ers from back then are still active. :thumbsup:

kramer5150 said:

1=Harry92382
2=**DONOTDELETE**
3=???? this user does not exist
4=MR Bulk
5=DavidW
6=??? this user does not exist
7=Brock
8=Clay
9=blackz28
10=YeeDude

Click to expand...

11=DaveH
12=ralphtt
13=dano
14=The_LED_Museum
15=Skyline
16=K Horn
17=SteveY
18=Size15's
19=E__WOK
20=Joe Talmadge

If you have a minute you should check in at the CPF, a decade after! thread as #20. :wave:

I'd forgotten, someone pointed that out to me a couple of years ago. I actually found CPF immediately, but waited a few weeks (or was it months?) before I actually joined. I coulda been top 10!