Introduction

Just a quick hello to the forum members.

Just acquired a Surefire U2 and like it (thou a little pricey !!!!).

Love all things in the lighting field and look forward to learning lots about the different sources of lighting and power solututions.

I use the the light for 2 reasons

Firstly I am a hunter and whilst I have a deicated rifle mounted lamp with variable power, I find the size is intrusive and as it driving a 50 watt halogen, the battery is a pain on the hip. The wiring can also be a pig when getting in and out of vehicles or if you have to put the rifle down etc.

The second reason is I love gadgets (that work) so do I really need to say more than that. Maybe it should really be reason number one.

I would also like to thank Cone for some initial help re lighting and the like - thanks Mark.

I think the first step is going to be to wean this great little light off the expendable 123's as they are damned expensive in the UK to say the least. I know I can buy in bulk but I use the lamp practically every day and even at a couple of quid a pop - that a lot of wonga plus a lot of waste for disposal too.

I suppose I only have one burning query and that would be to be how feasible it would be to build a small, adjustable power output lamp head onto a rifle but store the battery pack in the butt of the rifle.

It would need to be variable output (which is why I went for the U2 as a first time buy) but the ability to have a small but powerul beam (wide'ish field of view) would be cracking. For hunting a wider beam is helpful in case the quarry exits stage left - so hunting with a tight pencil beam would not be good.

Look forward to contributing to the forum,

Simon

Let me be the first to welcome you aboard, Simon!

There should be plenty of info around here to help with supporting your idea of moving your SF to rechargeable 123s.

Cheers!

If you have a U2 with a removable plastic tube, or an old U2 without the tube, you can fit an 18650 lithium ion cell. If you have a new U2 with the smaller inner diameter, you can fit only 17670 cells, which are still a good choice. Li-ions reduce brightness slightly at max power, but the other power levels stay the same, and with a 2600mah 18650 you have way longer run times than with 123a cells.

This guy will sell the li-ion charger (that no one here has reviewed yet, but I expect to be better than the DSD charger) separate if you message him: http://cgi.ebay.com/Luxeon-K2-Led-P...yZ106987QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

He sells cells too, or you can get the best higher end cells here: http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2763

User "AW" also sells these parts on the forum.

For part two, maybe a weapon mount for the U2 would serve you well!

Welcome to CPF, Simon. I think you'll get plenty of answers to your questions here, and your thoughts will always be appreciated.

Geoff

Welcome to CPF looman, you'll see plenty of fellow British flashaholics here.

Cheapest place for lithiums in the UK is here...

http://www.7dayshop.com/catalog/product_info.php?cPath=777_3&products_id=101444

You won't find better prices anywhere else.

I will leave it to others to advise on rechargables for that U2 you have (nice light).


CFU

Thank you for the welcome

So there are differing milli amp rated batteries in the rechargables and I have to watch out for diameter. Thanks for the heads up.

How do you get the plastic tube out without knackering it ?

Presume it is sensible to retain this for future use.

Thanks

Si

Loomy said:

If you have a U2 with a removable plastic tube, or an old U2 without the tube, you can fit an 18650 lithium ion cell. If you have a new U2 with the smaller inner diameter, you can fit only 17670 cells, which are still a good choice. Li-ions reduce brightness slightly at max power, but the other power levels stay the same, and with a 2600mah 18650 you have way longer run times than with 123a cells.

This guy will sell the li-ion charger (that no one here has reviewed yet, but I expect to be better than the DSD charger) separate if you message him: http://cgi.ebay.com/Luxeon-K2-Led-P...yZ106987QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

He sells cells too, or you can get the best higher end cells here: http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2763

User "AW" also sells these parts on the forum.

For part two, maybe a weapon mount for the U2 would serve you well!

Click to expand...

Loomy - The 2600 cell at the battery space link - is it protected or unprotected. I would rather build the numpty factor into it and get the protected cells. Lot of light to potentially mess up.?

Unprotected. Cells come unprotected unless it explicitly states there is protection built into the cell.

In my research I have found no need for protected cells in a U2 with even a cheap DSD charger. The U2 cannot over discharge the cell when working normally, and the charger cannot overcharge the cell when working normally. Such is the design of their circuitry, just like the circuitry in the protected cells. To my knowledge there have been no reports of a single li-ion cell malfunctioning in a U2.

Using protected cells just adds an extra layer of protection redundancy. It won't hurt to have, but in my realistic and pragmatic opinion, it is unnecessary.

That said, go with what you're comfortable with, for sure! 200 extra mah is probably just as useful as the extra protection, which is to say not at all.

New here also. Waiting for my Surefire L4!

I would suggest buying batteries from lighthound.com or opticshq.com as surefires can be found for £1 as opposed to the £2 on UK sites. Also, I hope you didn't make the same mistake I did when starting my collection which was to buy from UK companies. From the four torches I bought (A2, E2E, L4, E1L), lighthound.com would have saved me £150!

Welcome to the Jungle Simon

looman said:

Loomy - The 2600 cell at the battery space link - is it protected or unprotected. I would rather build the numpty factor into it and get the protected cells. Lot of light to potentially mess up.?

Click to expand...

looman, you might want to check out this post http://candlepowerforums.com/vb/showpost.php?p=1639261&postcount=10

More test results will be coming soon, but IMHO the 2600's are worth getting as you can see in this chart.

Also, welcome to the forum and congrats on getting the U2.

Welcome aboard and enjoy your U2.