Interesting fellfromtree... I was thinking of boosting the amps a little more - I'll do the resistor math and see. for the focusing, actually I didn't do any experimenting - should have. The throw is good, but hoping for a little better, but I'm not measuring ampds to the LED with 2 cells, so hard to tell. Are you having problems fitting 2 protected cells with these extensions?
I had to take off the button tops to fit protected. You can add o rings found too but that’s last resort sort of thing.
If you play with the depth on the dedome on a white surface about 20 feet away. You can see the light definitely loses throw at a certain point. Like it loses intensity- this is just with the naked eye though. The beam gets more floody if you go all the way in, but that’s what I noticed anyways.
Edit
If take a picture it looks different but you can see almost to the point of where it starts to get square… It looks perfectly round in rl. Maybe I need to play around with the camera some- but it has these 4 petals that come off the hotspot… Right at that point you have the richard simmons sizzler!
thanks tom e for the details, smaller quantity shims : 5 X Kupfer Kühlkörper Laptop GPU CPU Kühlkörper Kupfer Shim Sale - Banggood Deutschland sold out-arrival notice-arrival notice
Im watching this thread.
even a little cheaper at ebay:
sets of 10 pieces:
20x20x1mm = 3.62USD
15x15x1.2mm = 2.80USD
etc.
The eBay source though for qty 45 in 9 different sizes is still the best deal, if you want the variety of thickness's.
Instead of shims you can grind the base of the heAd down instead
I looked at doing that - won't the bare aluminum be exposed and seen? Specially if you have the light sitting head down? If so, does it look ok?
tome did you solder the shim with the led pcb ?
Yes - it's noted just above a pic.
I just took some measurements of LED current. The Stock current is between 2.4-2.6A over a wide voltage range. Power input is around 10W.
I will add a resistor and take measurements when I get the retaining ring out. It’s stuck and I used some oil and will let it cool down before I try again. The holes are a bit too small to use my good pliers and with tweezers it was unscrewable…
Edit:
I just played around with the driver. I soldered the driver to my test xml2 and played a bit. On stock there are one R180 and one R150. One added R100 boosts the led current to around 4.3A. Input power is around 23W
I also tried for a short period another R100 which gave around 6A to the LED at 35W input. After that I shorted something and needed to replace some parts so I couldn’t test the 6A for a longer period. After the repai the replaced FET wasn’t capable of the high current and I removed one r100….
I am now sure that the partly defective stock driver isn’t powerful enough for me in this light so I will probably also use a FET driver piggybaggedn one cell config.
Now I need to order a imr26650…
Thanks for the test results Werner. Did you record any output voltages?
Based on djozz’s Vf data I’m assuming >80% efficiency in stock form, down to <70% with one R100 added and <65% with two R100 added.
I didn’t took measurements of the led voltage(yeah I know that was lazy…) and you have to consider that I used a different led(noctigon on big heatsink) for the r100 test. The led voltage on the stock measurement was probably a bit higher than usual because the led was in the stock not ideal pressed down and got so a bit hotter. Also the input voltages are not super accurate so the data looks a bit worse than in reality I guess(that is why I didn’t post a lot datapoints). The regulation is not constant over the whole voltage range there are 10% fluctation like always on these buck drivers…but it is good enough to get an impression of the driver.
I also like a lot that this driver has voltage protection for one, two and three cells.
The efficiency goes down for sure a bit, I would also say efficiency is around 65-70%.
Think'n for my R100 moded light, add an ~R200 - think it would be a nice compromise. Also I have to play with the focus on that light a bit. Just wish I had time...
Another r200 will give around 5.3A.
4A in this light would really be a bit low for these days, especially because the heat sinking capabilities of this light seem superb.
Does anyone know a cheap source for the keeppower imr4200?
Looks alright to me! Did give it a quick rub with a finer grade and clean up the edge a bit.
Hhmm - yes, doesn't look bad, litle hard to tell form the pic. I'll have to give that a go.
Werner - sorry, no clue bout where to get the KP IMR 4200. I'm using the KK 26700's - got 8 of them.
My first Y3 I modded, used a DD driver (not sure if Nanjg w/FET or BLF17DD), and it was awesome - 1,700 OTF and bout 135 kcd, with a UCLp and XM-L2 U2 1A, and think I was only getting bout 5.6A.
I may not go that route, but it definitely looks like a good and attractive solution! Thanks for posting the pic.
Well… dangit. Got one of mine all put together with a shimmed up MT-G2 on a maxtoch mcpcb and with one R100 added. It looks good, but I’m underwhelmed. I feel like it ought to be brighter if it’s going to be this big. I suppose it’s time to piggyback a dd driver.
Also, the throw with an MT-G2 isn’t exactly fantastic. It’d better than an MT-G2 in a C8, but I’ve got a dedomed XM-L2 in a XinTD C8 (Mtn edition) with a stippled reflector driven by a BLF17DD that very significantly outthrows the MT-G2 in my resistor-modded Y3. I reckon I sortof expected that given the MUCH smaller emitter, but I didn’t expect the difference to be so very drastic. The Y3 is definitely a solid flooder with an MT-G2 in there. Small consolation: the MT-G2 fits in the stock reflector absolutely perfectly, and when shimmed-up (for me, the stock mcpcb measured about 2.0mm, whereas my maxtoch was about 1.5mm, and I added a flat piece of copper for a total of about 2.5mm in thickness), it looks pretty well focused. Just about back to square one on the driver, though. Also, apparently I’ve destroyed the driver in Y3 #2… lost a pad when adding an R100 (well, technically… I was removing the R150 and adding two R100s to see what would happen). Oh well. Maybe I’ll use the working driver with an XM-L2 (dedomed) and the dead one will get scrubbed and piggybacked.
The pair of sense resistors is in parallel. Losing a single pad shouldn’t put you entirely out of commission. Eh?
Yeah that’s what I figured, so I added two R100s on top of the R180. Worked long enough to briefly measure the current (around 6A, but that was before I modded my DMM, so who knows…), and now it won’t turn on anymore. Doesn’t have the fried driver smell, so I’m assuming something small got too much juice. And based on what I’ve done to it, I’m assuming that something small is one of the resistors I messed with that’s fried. Ah well. Gotta piggyback one of these anyway since I don’t like the results of one R100 out to an MT-G2, so I reckon I might as well strip the driver I fried.