Surefire L1 with 2 stage tailcap doesn't go high when it twisted to end.

[a1sealbeach]

Hello. I have Surefire L1 with 2 stage low/high gas pedal tailcap. I do not remember what generation is but not the oldest. When the tailcap pushed little, it turn on low, and push further tuned into high. However when I twist it turn on low and when I keep twisting, light goes low to few flickering and low light again until to the end. And when I push the tailcap then it has temporary high.
Is this fixable quiet easily by me or someone who are handy or has to be send to Surefire Tech Dept to fix? Thank advance for your commenting.

 

[carrot]

If you look inside the tailcap, what condition are the three leaf springs in?

 

[a1sealbeach]

It appeared one end of 3 leaf springs are 1/16" above the circuit board contacts evenly. The other side of springs are looked soldered on the circuit board. No missing springs.

 

[carrot]

Apologies for not finding my way back to this thread sooner.

As you may know, the way that this tailcap works is there is a resistor inside that current passes through if the leaf springs are not depressed, and that signals to the light to use low mode.

When the leaf springs are depressed all the way, the resistor is bypassed, and the light is signaled to use high mode.

I think that, either the contacts behind the leaf springs are dirty, or something has worn loose enough that it is no longer pressing the leaf springs deeply enough.

I would try disassembling the tailcap and see if you can improve the height of the contact that sits behind the leaf springs, or the entire switch assembly.

Failing that, I guess I would see what Surefire says. They have gotten pretty snippy over at their CS department, but the last generation of lights to use this style of tailcap would be the A2L and LX2, which are also quite old.

 

[Kestrel]

Has SureFire ran out of these tailcaps yet ? Sooner or later we will get to a point where SF will replace the light with a new model; we may be there already. I am being exceedingly careful with mine, FWIW.

Will be interested to hear how this current question resolves, thx.

 

[a1sealbeach]

Thanks for replies. I will not open the cap until Surefire says something. I provably one of few lucky guy who can step into their headquarter office and hold on tech guys to ask questions. Not because I am VIP but I live very close by them.
I acquired another L1 today and I looked inside tailcap very carefully, but can't see the differences at all. From the carrot's comment, those leaf springs must maintain certain different distance from the contacts, so it could give 2 different output by which or how many contacts are engaged. But how do I know which springs have to maintain specific distances. However that is my assumption on mechanical side, but also I can't rule out the possibility of burn or not working registers which Blindasabat described decade ago too.

 

[Kestrel]

That's not exactly it; the qty. of leaf springs are redundant;

To paraphrase Carrot:

On 'low', no leaf spring is making contact with the circuit board below, so the electrical circuit is the following:
Tail end, through the spring(s), through the 10 ohm resistor, into the central main spring, into the cell

When the tailcap is screwed down (or pressed) further, /any spring/ which now touches the circuit board, makes a short-circuit & avoiding the 10ohm resistor - obtaining 'High'.

 

[a1sealbeach]

Now I got it 100% how this L1 switch is working. Thanks for enlighten me.

Since I only couldn't get high when screw down to end ( but high comes on when button is pressed further at that point), I was suspecting that the body never push springs enough to make contact (shorten). So I made a experiment. I made a 14 gauge bare copper wire ring which is fitting just above springs, and put that into the tailcap. And guess what. Now it works! All I can think how this experiment is working, the internal of tailcap couldn't travel enough to make full contact for high at screw down to end, so the wire ring help to make contact.

I am still planning to visit Surefire to hear how the handle this tailcap issue along with my vintage 3DL cracked lexan lens.

 

[desert.snake]

Have you tried swapping the tailcaps on L1?

 

[a1sealbeach]

I did. Newly acquired L1 tailcap works both bodies as mean to be. Older tailcap with temporary copper ring also works both bodies too.

 

[a1sealbeach]

Ok. Call me curious George. Either I can't wait what Surefire says about this tailcap or I really wants to know how this tailcap works, I finally decided to disassemble myself. 2011 Blindasabat thread guide me but as he was predicted, I failed to remove top button with attached pin together as one piece. As he mentioned pull up with 2 small screw driver from opposite site by leverage from edge of tailcap body seems work but through the years of use and plastic get brittle by age, small top button part get snap off and left pin inside of internal switch.

I checked the gap of springs and those seems fine to me. Since I am not going to change the registers and experiment brightness as Blindasabat did, I was trying to figure out why internal switch didn't touch when it screw down to end. Then I concluded that contact spring on internal switch pushed up whole switch to ceiling of inside tailcap body and that cause gap which prevent firm contact on twist to end high. So I add shim on the top of internal switch not to push up to inside ceiling, which create permanent gap and also lower the whole switch part as thickness of shim.

And then I attached top button to body of internal switch by drill the hole and attached with tiny screw instead glue it. I don't trust glue. I reassembled boot and ring to hold and started testing. Viola! It worked as like new except it happens little bit early to engage contact than original tailcap. I believe that the shim I put was little bit thicker than it supposed to be. I can rearrange by put less thicker shim to control the position to make contact but decide to do it later.

Blindasabat said that remove pin as one piece is the point and you will know when you break, but honestly everybody will break no matter how they are careful. So old, so pushed repletely, dried out plastic pin meant to be broken in 2021. Well, that was my report to how to fix 2 way push L1 tailcap simple contact adjustment.

 

[sween1911]

Couple yesrs ago, I had the same problem as OP but with my LX2. They had to send me a new tailcap. Very small tolerance difference between bodies and caps causes the issue.

 

[bubbatime]

They sent me a new tail cap about 2 years ago for my ancient 4 flats L2. The anodizing doesn't match and I would prefer to rebuild or fix the original tail cap…. So at least they still had tail caps about 2 years ago.

 

[altermann]

it could be aviator tailcap they have different resistors inside