Convoy L2/L6 modding thread

Take a reading on the modified light or the stock light?

Too bad you don’t have a bench power supply, it is great for things like this. You can set it to a fixed output and ensure that the cells are not an issue.

Dale, did you check the cells of your luxmeter recently?

I’ve thought about it before, but that’d be just one more thing for me to learn how to use, forget how to use, and leave plugged in til it burned up. :stuck_out_tongue:

Have a $114 Sparkfun hot air station on the way, no soldering iron as I like my Hakko.

My lux meter is solar powered Mike. :stuck_out_tongue: hahahaha

Yeah, it’s got a new 9V cell. Comparatively new, anyway. This decade or something. I remember putting it in there but can’t say if it was 1 month ago or 6.

Been taking care of it… the cell that was in my meter was at 8.1V, the new one is at 9.5V. So now I have to start over. Ugh.

On my luxmeter when the batteries start goin low, the lux readings go up. Testing mods, that can be fun - wow that mod was awesome! But when the meter gets to that point, the low batt indicator is always there.

You must have a lot of amps killing the cells - maybe also heat, if you were doing them close back to back.

Stock gets my vote for this test.

So, here’s what I did… I used the modified black L6 with it’s 4500mAh Basen cells and I charged the cells fresh each of the 3 runs. I have a start number and a 30 seconds number for each of the 3 test runs. Before each test, I pulled the cells from my 8 bay Enova charger and measured the voltage. Each time both cells had stopped charging at 4.23V.

With No lens at all, I saw 7,590 lumens at start and 6,900 at 30 seconds.

With Stock AR lens, I saw 7,452 lumens at start and 6,762 at 30 seconds.

With the UCLp, I saw 7,279.5 lumens at start and 6,451.5 at 30 seconds.

So, with the cells at a common start value, fully charged, and with the light cool between runs, it seems pretty clear here. The factory AR coated lens outperforms the UCLp lens. At 172.5 lumens difference, it’s not a huge deal, but still. The factory lens is only dropping 138 lumens as compared to no lens at all. That is pretty remarkable.

Oddly enough, both with no lens and with the stock lens runs the light dropped 690 lumens in 30 seconds. But on the UCLp run it dropped 828 lumens. No obvious reason why.

It should go without saying that an unmodified light will show less difference than the highly modified light of these tests.

Essentially, it isn’t worth the trouble to change out Simon’s excellent quality AR coated glass lens. :wink:

4% (@start) to 6.5% (@30 secs) loss for the UCLp that supposed to have a 97% translucent rating. Hhhmmm. It's a fairly big difference - the 4% to 6.5%. I assume the cool down time was pretty long between trials because of the battery re-charging.

What's the thickness of the stock glass lens? The UCLp is 2.25 mm - wonder if that's factor, and if measuring without the lens is somehow measuring differently in the pipe light box, if that's what you are using - or a sphere. I know the pipe light box is position sensitive, but dunno of a lens/distance effect - dunno, maybe not a factor.

Tom, have you ever built one and then taken readings, used it, charged it up, taken readings again? It’s really rare to see the readings stay constant. I once thought it should always do the same thing, every time you tried it, but it just doesn’t work that way.

I think flashlights are female.

Yea, of course - lots of variations and still can't explain them all. Yep, been there... Technically I think there's an explanation somewhere - really think'n sometimes it's the cells since our typical DD FET builds are so dependent on them. Seems like charge cycles effect the cell resistance - whether a full charge or topping off, etc...

I got a lot of confidence in our pipe light box and luxmeters though - seen really good consistency there, when keeping the geometry consistent.

Tom, for the record Dale uses a calibrated light sphere. His comments may not always be P.C. :person_facepalming: but his data is quite solid. :+1:

Dale and I have the same pipe light box, made by the same person. I know he's been using it for years like I do, but I also know he more recently built a light sphere - I just dunno if he transitioned to using it. Good if he has. I have no clue what is going on why you have to be so defensive, I'm as curious as Dale is - I don't get your defending him because I'm not questioning anything, except trying to figure it out, same as I think he is.

Boy... calm down. I'm done - unsubscribed. Don't worry, you won't hear from me anymore on this.

I think the 97% rating from UCLp taken when the light is shining perpendicularly to the glass, with a reflector and lights going in many directions there could be some additional loses in the edge. Maybe due to the large diameter and reflector combination on the L6 somehow the stock glass happens to be more efficient.

I have never taken any measurements like Dale did but was always confident of the UCLp and believed it to be much better than a regular AR glass, although not as good as a a real optical grade glass.

It is nice that it only drops about 10% output even with the FET driver. Makes me glad I decided to go ahead with the TA driver for the L6. Particularly that narsil now supports thermal management.

I couldn’t get used to the sphere, gave it away and am still using my P Trap from manxbuggy and rdrfronty. Me, Tom and Richard, as well as manxbuggy and rdrfronty, all use the same P Trap design light box.

I learned over the past several years to not rely so heavily on the numbers but to enjoy the beam profile and actual output/throw/spill when in use. That is, after all, why I build em and push em (ok, I push em cause it’s just fun)

No worries Tom, it’s all good.

Tom, I’m quite confused here. Perhaps something came across different than I intended? I wasn’t being defensive and I’m not in the least bit worked up about anything said here. Dale doesn’t need defending as far as I know. I just remember him telling me he was using a calibrated light sphere so I stated that. It most definitely was not intended as any slight towards you or anyone else for that matter.

I certainly don’t want you to unsubscribe as I have a huge amount of respect for your work and want your input just like I want that of all those here. Particularly those like yourself, Dale and many others who are much more experienced than I am.

Just went back to the Black L6 to test amp draw at the tail. Cells haven’t been recharged, it’s showing 11.38A with the clamp meter. If I remember correctly (which would be a small miracle) it was making 11.7A on fresh cells which goes a long way towards explaining the rapid drop on the 4500mAh cells. :wink: Thought I’d toss that out there…

Dale, did you do any kind of write up on these 2 lights? I looked through your started threads and didn’t see them. I was thinking of the L2 with xhp35 myself to make a cheap version of the Acebeam K70 since it’s got a pretty steep price.