nicholiath Posted June 9, 2013 Report Share Posted June 9, 2013 Can you power a 12 volt lamp with 18650 batteries? I guess i would need to connect 8 together to achieve 12 v ? Would i need to wire them in series or paralell ? Quote Link to comment Share on other sites More sharing options...
evo Posted June 9, 2013 Report Share Posted June 9, 2013 would it not be easier to just power it with a 12v battery Quote Link to comment Share on other sites More sharing options...
nicholiath Posted June 9, 2013 Author Report Share Posted June 9, 2013 would it not be easier to just power it with a 12v battery yes.but i have some 18650 batteries and want to make a compact battery pack to tape to the rifle butt Quote Link to comment Share on other sites More sharing options...
FalconFN Posted June 9, 2013 Report Share Posted June 9, 2013 Voltage is just one part of the equation. Do you know what wattage the lamp is? You can work out the current needed by dividing the power by the voltage, so a 25 W bulb would need (25 W / 12 V) 2 Amps to power it. Quote Link to comment Share on other sites More sharing options...
nicholiath Posted June 9, 2013 Author Report Share Posted June 9, 2013 Voltage is just one part of the equation. Do you know what wattage the lamp is? You can work out the current needed by dividing the power by the voltage, so a 25 W bulb would need (25 W / 12 V) 2 Amps to power it. i want to power a 50 w bulb each battery is 3.7v so how many would i need? Quote Link to comment Share on other sites More sharing options...
FalconFN Posted June 9, 2013 Report Share Posted June 9, 2013 I'm no electrician but the maths says that 3 batteries at 3.7 V = 11.1 V so 3 batteries will give almost the correct voltage, but a 50 W bulb at 12 V will need a current of (50 W / 12 A) 4.2 Amps. To get the correct voltage they would have to be in series (end to end) but you would only have the current equal to one battery (it should say that on the battery). If they are, say 2400 mAh they can supply 2.4 amps of current each hour so your batteries could, in theory have enough oomph to light your lamp for just over half an hour - but in reality you won't get full power for all of that time, the batteries will fade pretty quickly and the lamp will probably get dimmer and dimmer from the first minute. There may also be issues with rapidly running down batteries and the ability for them to recharge fully, but I'm not sure on that front. Quote Link to comment Share on other sites More sharing options...
mick miller Posted June 13, 2013 Report Share Posted June 13, 2013 Just scrap the lamp and use a CREE torch. The old filament bulbs are dead and done now, no way would I go back to one of those. You can build a red torch that'll throw a beam over 300 yards and runs off a single 18650 battery for four hours, it fits in your hand (or pocket) for under £90, with the battery and charger, torch and all parts. Quote Link to comment Share on other sites More sharing options...
nicholiath Posted June 14, 2013 Author Report Share Posted June 14, 2013 Just scrap the lamp and use a CREE torch. The old filament bulbs are dead and done now, no way would I go back to one of those. You can build a red torch that'll throw a beam over 300 yards and runs off a single 18650 battery for four hours, it fits in your hand (or pocket) for under £90, with the battery and charger, torch and all parts. are you referring to the 501b with the ahorton conversion? Quote Link to comment Share on other sites More sharing options...
mick miller Posted June 14, 2013 Report Share Posted June 14, 2013 Yarp! Or Dave's conversion. Or do it yourself, you just need to drill the standard reflector out with a 20mm bit, then tap a thread with an M20 tap, shorten the reflector by about 5-6mm and black it. I just opt to use the complete Ahorton system and save the time but spend a little more. It's a little hit or miss whether or not customs will bend you over though and it's not worth ordering just one from him at a time. After that, spend about £28-£30 and get the chap off the candlepower site to build a boosted led in your chosen colour. They are reflowed directly to copper and boosted to nearly three times the standard amps. I'm not kidding, I've built several for people now and you'll get a useable image for shooting at x12 mag at 200 plus yards and you'll see stuff and eyeshine out to beyond 340 yards, and that's a conservative estimate. Plus you dont get a great big pool of light spilling everywhere. Who the hell would bother with a whacking great lightforce these days when you can get those results from a pocket torch? Quote Link to comment Share on other sites More sharing options...
evo Posted June 14, 2013 Report Share Posted June 14, 2013 would have to agree with mick, compared to the torches of old, these little WF-501b with the modifications will certainly be as good as if not better than the old torches or big lamps and the best thing is once attached to your rifle they are that small and compact and light you wouldn,t even know it was on your rifle, since I started building my own you would not believe just how good these little torches are, even some of my shooting buddies have decided to get rid of their old lamps and go with the 501b or the T20 , one has even got shut of his NS200 and gone with a homebuild because he thinks its better with his .223 in my honest opinion sell your big lamp and with the money build yourself a torch and get one of Dave-G,s mods,honestly it will open your eyes just how good these little torches are best wishes with whatever you decide to do , cheers Evo Quote Link to comment Share on other sites More sharing options...
gazbev Posted June 23, 2013 Report Share Posted June 23, 2013 If you connect four of your batteries end to end, positive to negative so they are in a line like this ---- with a positive one end and a negative the other it will power your lamp Quote Link to comment Share on other sites More sharing options...
mick miller Posted June 23, 2013 Report Share Posted June 23, 2013 But not for long. Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 2, 2013 Report Share Posted July 2, 2013 Hi there.. Connecting 18650 batteries in series can be very dangerous (apparently!) if there's just one battery that's not as powerful as the others, it can cause an explosion! I have an Ultrafire 3xT6 torch that takes two 18650 batts, I bought an extension to make it three batteries but was warned on Candlepower forum that it 's really dodgy and can turn the torch in to a pipe bomb The other two batteries that I ordered from China never landed anyhow and I got a refund today! There's loads of cheap excellent torches on the bay that come with batteries and chargers, you'd probably be best getting something from there- just be cautious about what the Chinese sellers put in their ads- the lumens count is usually half of what they claim them to be John Quote Link to comment Share on other sites More sharing options...
gazbev Posted July 2, 2013 Report Share Posted July 2, 2013 Batteries are not dangerous when connected in series,in fact the word battery means a number of, in this case cells,a car battery is a number of cell connected together in series to make 12v. A lot of lorry batteries are 24v and these are just two12 v batteries connected in series Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 4, 2013 Report Share Posted July 4, 2013 Batteries are not dangerous when connected in series,in fact the word battery means a number of, in this case cells,a car battery is a number of cell connected together in series to make 12v. A lot of lorry batteries are 24v and these are just two12 v batteries connected in series Hi Gaz The term 'Batteries' is loosely used these days, I did already know the a battery is made up of cells but i'll refer you to THIS Now tell me that it can't be dangerous connecting them in series I was directed to the thread in the link when I asked about my torch being upped to three of the 18650 batteries from two.. It mentions Li-ion (Lithium-ion) batteries, i'm fairly sure that Lipo (Lithium Polymer) are the same as they become very very hot during discharge so, not all batteries are dangerous but apparently, Li-ion definitely can be.. This is the torch and the extension that I bought from another seller in China.. It's extremely bright but the extra 3.7volts would make it fantastic! The extension is fitted in the pic below but i'd rather wait until I have at least three of a kind of batteries to lessen the possibility of coming to grief with these seemingly unstable sources of power!! As can be seen, I have three pairs of the 18650s but all three have different outputs and whilst they're all supposed to be be 3.7volts, the two at the left are marked as 4.2volts The batteries that I bought from China never arrived (identical to the Trustfire in the centre) so I still don't have a full set of identical outputs BTW, I take notice of the blokes on the Candlepower forums as they really know their stuff- if they tell me it's dangerous what i'm doing then i'll stop doing it as I love having all my limbs and not playing with worms John Quote Link to comment Share on other sites More sharing options...
FalconFN Posted July 4, 2013 Report Share Posted July 4, 2013 Is that a Seiko divers watch in the background? Sorry a bit off topic. Quote Link to comment Share on other sites More sharing options...
gazbev Posted July 6, 2013 Report Share Posted July 6, 2013 I would guess that its perhaps what the batteries are made of rather than them being in series but I can only guess,I can only tell you of my experience of working with large industrial batteries,these batteries are huge,all connected in a series of cells,the next time you look at a car battery and see the vents you can see that there are vents for each cell,all connected in series. A cell puts out about 1.5 volts,when you put two batteries in a torch these are in series to make it brighter or kids toys,they are the same making more volts to perhaps make a motor work.if you open a 9v battery,the type you see in a smoke alarm you will find 6, 1.5 volt batteries connected in series. The electrical principles are simple,batteries are and always have been connected in series,what happened here is a mystery to me so until there is a news flash on BBC World saying the bomb squad are coming to pick up people's tv remotes children's nightlites and rampent rabbits,I will sleep soundly. Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 8, 2013 Report Share Posted July 8, 2013 Hi Gaz From that post on CP forum, I couldn't bring myself to use the extension and mix the batteries so I ordered another set of the Trustfire ones (Recommended as being good quality at a low cost!), six weeks later they haven't arrived and recently got my money back!, I still won't mix them (I must seem a right wimp!! ), one day i'll get round to buying some more and see if I can light up the moon!! A lot of years ago my dad got me a set of those 5" chrome Lucas spotlamps for my old Sunbeam Alpine, he said I could try them on a car battery that was under the window on the front of the house, I touched the wires on to the terminals and.... BOOM!!!!! He didn't tell me that it had been on charge all night through the window and Hydrogen had built up and went off alarmingly!!.. The battery was one of those old fashioned thick black ones (looked like shiney tar at the break!), bits of the battery were at the other side of the road, around sixty feet away and amazingly, neither me or my brother were hit by acid or the shrapnel!!! My ears were going Beeeeeeeeeeeeeeeeeeep for a couple of days though! One thing is though that people often learn by their mistakes and now whenever I do anything with lead acid batteries, I always blow in the cells to clear the gas (just in case!) Dunno what to do with those 'sealed for life' ones though Cheers, John Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 8, 2013 Report Share Posted July 8, 2013 Is that a Seiko divers watch in the background? Sorry a bit off topic. Sorry mate I missed your question, not a Seiko but a Rhula dive watch.. I removed from the leather Nato and put it on a grey fabric Nato as it was more comfy! I've a few other divers watches (i'm not a diver though ) Some are Seikos.. John Quote Link to comment Share on other sites More sharing options...
FalconFN Posted July 8, 2013 Report Share Posted July 8, 2013 Crikey, I should have guessed you had more than one watch! I can see at least 5 Seikos (7s26's ?) there - real classics and I love their design with the offset crown. I put a nato strap on mine too - much better that the rubber one. Thanks for the pic. Quote Link to comment Share on other sites More sharing options...
gazbev Posted July 8, 2013 Report Share Posted July 8, 2013 John,sorry had to laugh I bet you jumped a mile when the hydrogen went up. Nice watches though have a cole of seikos myself, one auto relay and the other is a military style watch that looks a little like the fourth one in from the left but had a green fabric strap, had it for years ans dropped it on the kitchen floor and smashed the glass, I took it to a few places and they wanted too much to repair it (80 quid plus) so it's in the draw now not being used. Got a cheap Casio at the mo because I can't find one the same,the new ones are solar powered, can't see the point the batteries last six years, if I can find one of the old ones I would buy it Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 10, 2013 Report Share Posted July 10, 2013 Crikey, I should have guessed you had more than one watch! I can see at least 5 Seikos (7s26's ?) there - real classics and I love their design with the offset crown. I put a nato strap on mine too - much better that the rubber one. Thanks for the pic. Hello Falcon I've been collecting watches for quite a few years, this pic is a little less than half of what I own! John,sorry had to laugh I bet you jumped a mile when the hydrogen went up. Nice watches though have a cole of seikos myself, one auto relay and the other is a military style watch that looks a little like the fourth one in from the left but had a green fabric strap, had it for years ans dropped it on the kitchen floor and smashed the glass, I took it to a few places and they wanted too much to repair it (80 quid plus) so it's in the draw now not being used. Got a cheap Casio at the mo because I can't find one the same,the new ones are solar powered, can't see the point the batteries last six years, if I can find one of the old ones I would buy it Hi Gaz I presume that the crystal was a flat mineral glass? If it's a domed acrylic I have almost all the sizes that are produced for wristwatches but the mineral I only have very few.. Was your Mil Seiko like this one but with a green dial?? Cheers, John Quote Link to comment Share on other sites More sharing options...
gazbev Posted July 11, 2013 Report Share Posted July 11, 2013 (edited) Hi John, yes here is a pic,great watches by the way,great collection. It does have a green face and strap and a domed glass. Edited July 11, 2013 by gazbev Quote Link to comment Share on other sites More sharing options...
johnbaz Posted July 12, 2013 Report Share Posted July 12, 2013 (edited) Hi John, yes here is a pic,great watches by the way,great collection. It does have a green face and strap and a domed glass. Hi Gaz I used to have one very similar to this one but mine had a flat mineral glass fitted.. I love these Seiko chronographs and have a few mechanical ones from back in the 70's.. Here's a 6139, 30minute chrono.. another.. Another two (parts watch and one OK, both work but minute counter hand is missing).. 6138 Bullhead chronograph.. Another 6139.. Here's a modern day Quartz chrono, Seiko 'Alfie' I've fitted crystals in the past (Have some and the compressor to fit them), If you want to post your watch to me i'll see if I have one to fit and then send it back to you.. EDIT- looking at your watch I think it's domed hardened mineral glass (it will feel like glass, cold and hard), acrylic is a type of plastic which is soft, you can't usually fit an acrylic where a mineral glass has been as the bezel has a different profile and the sharp edge of the acrylic won't hold in John Edited July 12, 2013 by johnbaz Quote Link to comment Share on other sites More sharing options...
gazbev Posted July 12, 2013 Report Share Posted July 12, 2013 Love the one with the blue face its a hard choice but my favourite has to be the 6139 in your hand, a real beaut. If you PM me your address I will send it to you,if you can fix it give me a price I would love to wear it again Cheers Quote Link to comment Share on other sites More sharing options...
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