I have a couple of these small and cheap, yet powerful Cree LED torches similar to this: https://www.ebay.com/itm/311764537238?rmvSB=true

Rather than re-invent the wheel, I feel sure that others will be able to tell me a simple and cheap method of fixing them to the side of a helmet?

Thanks.

drill some holes in the side of your helmet and use either snoopys, bungie or cableties depending on how permanent you want it.

I checked out this torch . . . superficially it looks good, but I was a bit bemused by seeing this in its specification: 

Battery Type: 1* 18650 Battery(OPTIONAL)

Presumably you're referring to the OPTIONAL battery.  You can buy very good ones by makers such as LG (3500mah) or Samsung (3000mah) for a fiver or so, which still means they're cheap. Their light output has allowed me, at last, to bin my FX2 and Oldhams with not the least regret. Just a pity these gems weren't available 50 years ago

Drill holes and bungee...... of course. Many thanks.
 

Hi halkyn, there have been warnings on here about using cheap 18650 batteries . . . maybe you should fork out for the more expensive ones ? or at least check out the cheap ones first (the Fenix ones I use cost more than those torches). I do agree with you about FX2s (& 3s) and Oldhams . . . as, I imagine, does every other caver in Britain.

The fenex batteries are just re-branded Panasonic (i think) cells. Protected Panasonic cells shouldn't cost you more than about ?6 each or so. Fenix cells are a ripoff.

B

Most quality cells now are rebranded Panasonic or Sanyo, now both the same company.

Thanks for your comment Roy.
In view of your depth of knowledge on the topic, can you tell me if I've wasted part of my well-earned pension on these: https://www.ebay.co.uk/itm/Genuine-LG-INR-18650-MJ1-3500mAh-10A-Batteries-Hi-power-Vape-eBike/182953797961?ssPageName=STRK%3AMEBIDX%3AIT&var=690270917045&_trksid=p2057872.m2749.l2649
I appreciate that any such ebay purchase is not without risk, but it would be good to get informed input.

I have no idea, but can be helpful with advice on how to easily identify fakes and duds.

First, eBay. A seller to be trusted is Marj who sells genuine OEM Sanyo 18650 3500 mAh. I buy off her, she lives down the road from me and gets them from Europe. Fasttech China who are genuine are currently having shipping difficulties to the UK.

Anyway. LiIon cells leave the factory at a voltage suitable for storage. The above mentioned cells are at 3.47 volts, give or take about 0.1V, depending on storage time. However, if you buy several, the same batch should all read exactly the same. This condition is very difficult to engineer artificially by a seller of fakes or duds as it would be impossible to get the charge levels all exactly the same, and they would loose uneven amounts of power in transit, such is the nature of junk cells. Once they have had the first time charge obviously this condition has gone and the only hint would be to test them fresh off charge, then again after say a week to see if any loss. After charge, good cells will, 'settle' so to speak, we are talking though about 0.01 volts.

Apart from this I cannot help with the above, but obviously seller feedback could give indication.

I have just took a second look and his comment re: "all cells are tested to be same voltage for the building of large battery packs, " is basically same as what I say above. A faker would not want you to know this.

Many thanks Roy. Very helpful.

Make a loop of sturdy (at least 7 mm diameter) bungee, which is a tight fit on the helmet. Attach the torch to this loop with cable ties. This has two advantages over what's suggested above: no need to drill your helmet (see concerns raised in another topic) and easy to take off for cleaning mud off helmet (which is slightly easier when stuff's stripped off it). You can also transfer it between helmets very easily (e.g. if a mate wants to borrow your light). If you can detach it easily you're more likely to clean & grease the O-ring in the bezel, so less chance of it leaking (which is the beginning of the end for any torch).

Just a word about comments above along the lines of throwing conventional headlamps away; torches mounted on the side of your helmet (compared with a central lamp at the front) are a complete pain in long narrow rifts or constricted crawls.

Make a loop of sturdy (at least 7 mm diameter) bungee, which is a tight fit on the helmet. Attach the torch to this loop with cable ties.

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I assume, since you're advocating this, John, that the bungee cord stays in place? I doesn't just roll up and off the top of the helmet?

Yes - that's right. I was shown this trick by a TSG friend a few years ago and I've kept a small backup torch on my helmet ever since. (If you want me to send you a photo directly, send me a PM. and remind me of your email address. Never really did fathom out how to post pictures effectively on this forum.)

I guess there must be some helmet shapes which do make the bungee roll upwards; in this cases  the bungee might need to be held captive in some way (there is a range of options, depending on which helmet is used.)

halkyn said:

Their light output has allowed me, at last, to bin my FX2 and Oldhams with not the least regret.

Click to expand...

Don't bin the Headsets. It's relatively easy if you can cut and shape a bit of aluminium plate and do a bit of soldering to make your own LED insert. Then all you need is a helmet mounted battery and you're away.

halkyn said:

Thanks for your comment Roy.
In view of your depth of knowledge on the topic, can you tell me if I've wasted part of my well-earned pension on these: https://www.ebay.co.uk/itm/Genuine-LG-INR-18650-MJ1-3500mAh-10A-Batteries-Hi-power-Vape-eBike/182953797961?ssPageName=STRK%3AMEBIDX%3AIT&var=690270917045&_trksid=p2057872.m2749.l2649
I appreciate that any such ebay purchase is not without risk, but it would be good to get informed input.

Click to expand...

More on this.
I have had some correspondence with this seller Adibera who comes across as a real nice guy and very open. I have bought his current remaining stock of NCR 18650GA. Just arrived and tested a selection all at 3.48V indicating a fresh batch. After being in stock for time the cells drop to 3.47V which is what I have been getting from Fasttech Hong Kong.

In view of this, I recommend him as seller, his prices are certainly good and probably reflects the quantities he buys in at.
Hope this is helpful.