Cavers - The StenLight, Ultimate 2x3W LED Headlamp

[JonSidneyB]

No bubbles from the battery pack at all...and it is running underwater right now.

On durability. One has been dropped from 35 feet onto concrete then was swung by the power cord taking chunks out of concrete, the selector switch was bent but works fine after straightening out.

When I have the time, we are going to make a movie of a Sten getting abused and still function.

These lights can take it.

[NewBie]

No bubbles from the battery pack at all...and it is running underwater right now.

On durability. One has been dropped from 35 feet onto concrete then was swung by the power cord taking chunks out of concrete, the selector switch was bent but works fine after straightening out.

When I have the time, we are going to make a movie of a Sten getting abused and still function.

These lights can take it.

Hi Jon.

Are you saying you took chunks out of the concrete with the battery pack or the aluminum head portion?


Some of the mine/cave water around here is actually acidic and in other areas alkaline, you might try running in a vat of that...

[JonSidneyB]

The head portion

[NewBie]

This is what I was referring to, as far as non-pure water and unsealed connectors the other day.

I have some mine water I collected while rockhounding, that I have actually been letting sit for many months now, watching crystals grow out of it as it evaporates. I'd collected it with my water bottle, as I'd noticed the crystals growning on the edges, and wondered if it was salt, calcium, or what...

I stirred up the mine water a bit, then I poured some of the water into a fresh jar, and added about the amount of tap water needed to bring it roughly back to the concentration it was. I also took a chunk of the stuff that grew on the side of the old jar, and tossed it in the bottom.

I then took 2 Li-Ion cells and hooked them to the Molex connector.

Unfortunately the water is very murky, and things are hard to see.


.


A close-up of what is going on:


.


After fifteen minutes, I pulled it out and took a picture of the contacts:


You can see the plating is gone from one contact exposing the copper beryllium or phosphor bronze base metal, the other contact has a black coating, and the other two contacts without power applied are normal looking.

Hopefully this clears things up.

IMHO, if the unsealed connector gets water in it, it would be a really great idea to take it apart and blow it out on both ends.

Another thing folks could try is wrapping the connector tightly from the cable, over the connectors, and back over the cable, tightly with one of the electrical tapes that has stretch to it, keeping it tight at all times, and back wrapping it at one end.

Something else a person can use (to help-not fix), is the silicone grease they use with Marine battery terminals, to prevent corrosion (btw, it works great on car battery posts too...)

[JonSidneyB]

I don't recomend for normal use the things I am going to do to this light. I actually think a caving light should have the battery up and out of the way. In the even that this light does get dunked, I think the tests will show that it can take it. If the light ever does get dunked with lots of uglies in the water, clean it up when you get the chance. The litium pack is rubber armored but I am going to see if I can get an armored case to go around it made unless you guys know of a case that already exists for that purpose.

[SilverFox]

Hello Newbie,

What kind of run time did you get until the bubbling stopped?

Tom

[cy]

a super cool option would be to make a CNC aluminum case that holds 2x R123 li-ion cells. simply use protected R123 to avoid protection issues.

weight reduction for headband use would be pretty coool, with bash protection too.

come to think of it, the $1 match case may work with a little modding.

[jtice]

I have been thinking about making a wired cap, to use with one of my 2x123 bodies,
and using that for a super light pack for headlamp use.
Bare in mind, you will need a minimum voltage to fire up the Sten,
2xR123 would just do it I think.

~John

[wasBlinded]

Using a 2xR123 pack you would need to cut the expected runtimes by 75% compared to the 18650 pack, but for casual use I think that would be fine. It should easily give 2 hours on High and 8 hours on Medium.

[NewBie]

Any idea how it would hang in there on Turbo with 2 r123?

[PeLu]

a super cool option would be to make a CNC aluminum case that holds 2x R123 li-ion cells. simply use protected R123 to avoid protection issues.

As NewBie mentioned, the two R123 cells will not be enough for the Turbo mode and further you pay double penalty for the protection.
The Stenlight battery pack has a quite good protection electronic (altough no balancing) and it is always better to let the work done by one circuit instead of two independant ones.
I'm quite shure, the drop will be more than 75%, anyway.
The use 18650 cells are about perfect. Very good specific engery, load capability very well suited to the needs and easily available (=economic).

I've made now several batteries, most with 2 cells, but also some with 4 cells. I use a slightly better protection electronic than the original, but differences are not that dramatic (no balancing either, but an external contact for it to be done by an external circuit).
As I also use very good cells, unbalancing has not been an issue now.

As I wrote, I changed to quite small BEC connectors (which have an incredibly low resistance too) and we had a few cases where cavers had to go through a duck (that sometimes means that you have to put yourself compeltely under water, so the light is compeltely submerged, only for a moment, but it will stay wet).

We did, as NewBie mentioned, I greased the contacts with petroleum jelly (the only grease we had at hand) und I wrapped it with insulation tape. This worked very well, but karst cave water is usually not very conductive (which slows things down but does not prevent them).

With greased contacts you have to be very careful when changing batteries in a cave. The grease attracts mud magically .-)

And, BTW, I've seen so many corroded contacs in my caving career I cannot tell.
Always beware that the corrosion is independet if the light is switched on or off. As long as there is voltage across the contacts it will corrode.
The higher the voltage, the worse.

For protecting the cells in my battery packs I changed to 'half shells' only on the outer part, the inside (towards the helmet) is only protected like the original StenLight battery pack. This saves weight and the need for a perfectly fitting tube size.
My battery packs (o.k. the latter ones) are fully waterproof and I may change to waterproof connectors (not decided yet).

The 'attach a helmet mount to the end of a battery tube' has been already made long time ago (I think I've seen it in the 70ies or 80ies) . A caver used to use D-cells in a quite long tube (4 or 5 of them) and a miner's light headpiece. So it was the logical step to make such an helmet mount (or just the slot) on one end of the tube for non-caving use.

[noelex]

Can anyone give me details (such as model number and where they can be ordered) of the connectors used in the Stenlight ?
Thanks John

[wasBlinded]

As NewBie mentioned, the two R123 cells will not be enough for the Turbo mode and further you pay double penalty for the protection.
The Stenlight battery pack has a quite good protection electronic (altough no balancing) and it is always better to let the work done by one circuit instead of two independant ones.
I'm quite shure, the drop will be more than 75%, anyway.

A typical R123 has a capacity of about 600 mAh, compared to an 18650 of 2400 mAh - i.e. it has 75% less capacity than an 18650 and should give about 25% of the runtime. I feel pretty confident about that, so will stand by my previous statement. The 2xR123 battery pack will run the Stenlight in full turbo mode for 20 minutes or so (my WAG), but the 900 mA draw of Turbo (when the light is not temperature limiting) is a pretty good strain on the R123 and not really recommended. The 270 mA draw on High is no strain at all for the R123 and should easily give 2 hours of runtime.

[PeLu]

A typical R123 has a capacity of about 600 mAh, compared to an 18650 of 2400 mAh - i.e. it has 75% less capacity than an 18650 and should give about 25% of the runtime.

Capacity drops at higher loads and the protection circuits have higher losses (as they are two and desigend for lower loads). Because the resulting voltage is lower, the switching circuit will draw even more current (probably the first part of the dischrage) or the light will dim down. Anyway, the gained space and weight is not too much compared with the standard pack, so it is IMHO not worth trying it at all. Together with more hazzle charging it.

Connectors: The inavailability (here!) was one of the reasons we changed the connectors.
People wanted either a waterproof connector or one small enough to fit it inside the helmet (of course, both features together would have been perfect, but not realistic). We decided for the latter.
Further, tehre is at least one reported problem with the stock connector.

[cy]

need to clarify.... when I posted comment about using 2x R123's. it was intended for headstrap use to reduce weight.

naturally runtime would go down. agree that using stock 2x 18650 pack is the best for overall performance. surely one of us will figure out an EZ clam shell to protect 18650 pack.

what sealed connectors should we be looking at?

[benh]

I'm thinking about a 4x18650 pack for increased runtime. Batteryspace had a few likely prebuilt packs out there.

I think the stock pack will fit in an Otterbox 1000.

[wasBlinded]

Capacity drops at higher loads and the protection circuits have higher losses (as they are two and desigend for lower loads). Because the resulting voltage is lower, the switching circuit will draw even more current (probably the first part of the dischrage) or the light will dim down. Anyway, the gained space and weight is not too much compared with the standard pack, so it is IMHO not worth trying it at all. Together with more hazzle charging it.

This might be significant in Turbo at the 900 mA draw, but on High, at 270 mA, these effects will be negligible. Whether it is worth doing for the weight savings was not the question.

[JonSidneyB]

I need to get around to trying the 9volt on a Sten... I have yet to do that.

[niemidc]

This is what I was referring to, as far as non-pure water and unsealed connectors the other day.
...
Another thing folks could try is wrapping the connector tightly from the cable, over the connectors, and back over the cable, tightly with one of the electrical tapes that has stretch to it, keeping it tight at all times, and back wrapping it at one end.

Something else a person can use (to help-not fix), is the silicone grease they use with Marine battery terminals, to prevent corrosion (btw, it works great on car battery posts too...)

A couple of comments on this test -- we've done tests too. The connector fares a lot better when both sides are plugged in as this decreases the current through the water significantly, and better yet if you use dielectric grease on the contacts of one or both sides. The dielectric grease has a larger effect than, say, moving to gold-plated contacts. The connector in the picture looks like the larger (.093" contact) 4-pin molex with just 2 pins in it. Also, we use the gender shown on the LAMP side, as if you use that polarity on the battery side it can be easily shorted by a small metal object (and also worsens corrosion if it is exposed to water).

There are some types of water found in caves that are exceptionally corrosive and penetrating. On one trip to Warm River cave (Virginia) we had a fantastic number of equipment failures, including of a watch that I'd worn underwater for years. This was in the pre-StenLight days...

[niemidc]

Only thing I'm not sure about is the stability of the blade pivot. I can't tell if the light is gradually pointing downward due to road vibration or not. I kepy messing with the aim as I rode so it's hard to tell.

The swivel can be tightened with a crescent wrench (or a 5.5mm hex socket if you have one). Don't tighten it more than a tiny bit without checking to see the effects, it doesn't take much to make it much tighter.

[JohnnyM]

Hi All,

been following the Sten thread, very interesting, especially all the mods, battery packs and helmet mounts etc. Couple of things occurred to me.

First, doesn't anyone make a neat, slim, waterproof connector for cables? Maybe something designed for a marine environment, which is extremely harsh on metal contacts, live or not. The nearest I've seen came with a Silva L1 headlamp, a brilliant little lightweight 3W Luxeon model, with the alternative of headband-mounted battery packs (2 packs, each with 2AA, to spread the load for night-running/orienteering) or a remote pack with a longer cable (4 x C cell for long life). The system was not intended to be waterproof, but the connector was excellent (circular in section, diameter of about 7 - 8mm), and to switch between the different battery options took about 30 seconds - just unplug the short cable and plug in the long one. I don't expect you'll have seen one, as Silva are imported (I believe) in the US by Brunton Industries, who don't seem to want to sell anything or make money ;-). I much prefer a (bigger) battery pack on a waist belt. On your head/helmet, it is vulnerable and uncomfortably heavy.

Second, Sten seem to be a bit slow with the headband option, so could I suggest (afraid I don't have the facilities at the moment to show/demonstrate) making an aluminium plate on the same pattern as that supplied with the Prolite strap system? Get a plate, cut two parallel slots, push centre section out slightly, add end and top slots for straps, round off all sharp edges, glue foam rubber backing, take the straps from a Prolite or Petzl and attach. Or cannibalise an old Petzl Zoom mount and go from there (simple, light, tough plastic, three straps, all still replaceable)?

Oh, one other thing. Re. bicycle lighting: if you ride offroad at night, it's dead useful to have a good headlamp as well as a bar-mounted system. On singletrack, the lights on the bars don't point exactly where you need them to go!

Take care out there,

JohnnyM.

[cy]

welcome to cpf Johnnym...

highly recommend jumping in and getting a stenlight. personally don't have any problems with clipping in stenlight to prolite strap. straps could be a little wider.

you'll find stock 2x 18650 pack weight not very objectionable at all. or use longer cable and mount on your waist. another option is to use 9V cell in headlamp mode. this would reduce mass and runtime.

I've never done a 9V runtime test. would someone post the runtime for 9V?

[paulr]

Here's some sealed connectors, but they are expensive and look kind of big:

http://ecatalog.westmarine.com/0541....kProdId=165104

[ianb]

Has anybody tried the reflectored version with the new Seoul P4 LED's?,
they should increase the output considerably and with a different regulator(lower mA levels) should give much longer runs on the standard battery.
I have wanted an S7 for some time, I have been waiting for the reflectored version to be official and think this would make an excellent upgrade.

Ian

[Lurveleven]

The Stenlight is already too bright for most use and has awsome runtime, but for turbo mode brighter is always better so I would have loved to have it with P4 LEDs, even if it was just to impress my friends
However, so far I have mostly used it on medium and low and would actually have liked the low to be lower.

Sigbjoern

[Mark620]

And, BTW, I've seen so many corroded contacs in my caving career I cannot tell.
Always beware that the corrosion is independet if the light is switched on or off. As long as there is voltage across the contacts it will corrode.
The higher the voltage, the worse.

I have repaired caving lights(replaced wires) because the wires were corroded end to end...(from battery pack to bulb)

[slvoid]

A little expensive, but waterproof to 3-6'.
http://store.jbn-duraline.com/catego...and-receptacle

[wasBlinded]

Has anybody tried the reflectored version with the new Seoul P4 LED's?,
they should increase the output considerably and with a different regulator(lower mA levels) should give much longer runs on the standard battery.
I have wanted an S7 for some time, I have been waiting for the reflectored version to be official and think this would make an excellent upgrade.

Ian

I replaced the optics in my Stenlight with textured reflectors. The reflectors give a wider spill light than the optics. This helps with peripheral vision, but also is a little more annoying to fellow cavers. I wouldn't say that the overall output appears brighter, but the beam is smoother with fewer artifacts.

I've also replaced the Luxeon LEDs with SSC P4 Leds. Because the focus changes with the SSC, the extra light output goes into a larger but not more intense hotspot.

[hadsnat]

hi been lurking in the shadows for a while,decided to get myself a new light,where have most of you purchased your stenlights from? was it from pratt hobies or from somewhere else,has anybody had problems ordering from overseas through the pratt hobies store,i'm living in new zealand so makes things kind of hard.

[cy]

welcome to cpf hadsnat... you cannot go wrong with Stenlight.

there's trusted folks on cpf that will forward lights to cpf're intn ... highly recommend insured shipping. cheap within US, but expensive overseas ($25).

JSBurley was shipping intnl (out of stock), http://www.jsburlysflashlights.com/c...ref=Head+Lamps

don't know if Stenlight will ship overseas direct, but it's worth a try..