Surefire 8AX commander bulb performing poorly!?

I am curious, just a ball park idea, how long an incan bulb can continue to operate at peak performance!?! My 8AX commander is dim at best. I have owned this light for approximately 2 years..maybe a tad longer and have never replaced the bulb because it has never burned out! My batteries are custom from Silverfox so I think they are still good to go although I do not have a way to test the batteries. Not to get off topic...what is the ball park range in terms of months if the light gets used nightly / 6 nights per week.

If the bulb envelope is still clear and not blackened it should be operating at full brightness. Have you checked and cleaned all the electrical contacts in the light? Resistance has a HUGE effect on incan brightness. Clean contacts can make all the difference in the world.

It sounds to me like you've had good life out of that X80 lamp. I suggest swapping it out for your spare and getting a replacement.

I don't believe it came with a spare. But it is probably time to replace regardless! I may see if Gene can make a P7 mod for it. Thanks guys!

What do you clean the contact with and which contacts are we speaking of. I ask because I have obviously never cleaned them..ever!

Yoda4561 said:

Have you checked and cleaned all the electrical contacts in the light? Resistance has a HUGE effect on incan brightness. Clean contacts can make all the difference in the world.

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There are no contact points on the Commander. The buld is designed to make contact with the battery only; both positive and negative contact points are on top on the battery.

I think the bulb has had a long service life....time for a fresh one.

Policetacteam said:

I don't believe it came with a spare. But it is probably time to replace regardless! I may see if Gene can make a P7 mod for it. Thanks guys!

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SureFires don't need to have spare bulbs onboard - the bulbs have extremely long lifespans as you've experienced.

Still, I'm of the opinion and experience that its a good idea to have a spare lamp around for when the bulb dies of old age or just in case it breaks.

Deoxit (the red original kind) is the best stuff, it's great for switches and contacts and all sorts of things, some of which can't be cleaned by hand. In your case though it should be a simple matter to use some metal polish or very fine sandpaper, and wherever the light makes a mechanical electrical contact.

A list off the top of my head are the lamp center contact, the lamp outer spring (around the bottom where it contacts the light body), the rim inside the flashlight body that the outer spring contacts, the tailcap spring, the inner tailcap contact and the base of the flashlight battery tube which usually makes contact with part of the tailcap switch.

I'd clean the outer spring and center bulb contact, the battery ends if they look even a bit duller than when new, and the tailcap spring. It should take just one or two passes with the sandpaper to brighten up the metal, you aren't trying to remove it, just cut through the oxide buildup. Deoxit does this chemically, but abrasives work just as well, not nearly as convenient though (it's great for tailcaps and other non-easy to clean areas), and deoxit has the benefit of keeping stuff working so you don't need to hit it with abrasive paper as often.

DUQ said:

There are no contact points on the Commander. The buld is designed to make contact with the battery only; both positive and negative contact points are on top on the battery.

I think the bulb has had a long service life....time for a fresh one.

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I've never owned one personally so I'll take your word for it, but it seems odd what with the battery having pos and negative contacts on opposite ends. The pictures I've seen show a pretty run of the mill surefire build, with the same contact areas as any 6p/g/etc light.

SureFire B90 battery sticks have both positive and negative terminals at the top end of the battery stick, as well as a negative terminal at the bottom.

Geez I want to get one now just to see how it's all put together. How on earth does the tailcap switch work if the bulb is already in contact with the battery's +/- terminals?

Size15's said:

SureFire B90 battery sticks have both positive and negative terminals at the top end of the battery stick, as well as a negative terminal at the bottom.

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I wonder whats the logic in that? :thinking:

Yoda4561 said:

Geez I want to get one now just to see how it's all put together. How on earth does the tailcap switch work if the bulb is already in contact with the battery's +/- terminals?

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It's like the B90 battery stick is a piston - the push button at the rear of the body is simply a means of pushing the whole battery stick forward so that both the Lamp Assembly spring contacts make contact.

The Lamp Assembly outer spring contact (negative) is far longer than the inner (positive) spring contact.

Pushing the battery stick towards the bezel makes the contact with the positive spring. Normally at rest just the negative spring is in contact.

Illum_the_nation said:

I wonder whats the logic in that? :thinking:

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This is because the charger has charging terminals at either end. Achieving robust, reliable and 'foolproof' recharging using a system with both terminals at one end is likely far more difficult.
The B90 is used by both the 9AN and 8AX/8NX/L7 so it has to have have a negative terminal in the traditional location because the 9N/9AN operates like a traditional TailCap-operated flashlight.

Al

Size15's said:

This is because the charger has charging terminals at either end. Achieving robust, reliable and 'foolproof' recharging using a system with both terminals at one end is likely far more difficult.
The B90 is used by both the 9AN and 8AX/8NX/L7 so it has to have have a negative terminal in the traditional location because the 9N/9AN operates like a traditional TailCap-operated flashlight.

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you :rock:

The "negative" terminal on the bottom of the battery stick has two thin, flat metal strips, soldered to a flat plate on the bottom of it. These two strips run up the side of the three "sub C" NiCd :thumbsdow cells (which are soldered together with tabs), to a "washer" that sits on top of the "positive" terminal (insulated from it, of course), and then the whole thing is shrink wrapped to make the "stick".

The tail (no cap, no contacts) in the one piece Nitrolon body is nothing but a large rubber boot, that when you press on it simply pushes the entire battery stick forward to make contact with the LA's springs, sort of like a "piston drive". The large outer spring on the LA is in constant contact with the "negative washer" on the battery stick, thus giving it "tactical feedback". The inner spring is shorter and recessed into the outer one, not making contact with the "positive nub" on the battery stick until the tail "button" is depressed. The most simple, effective, mechanical connection between a power source and a LA ever devised; brillant!

Too bad SF chose NiCd for this setup, but I'm going to have to look into the OP's "Silverfox" mod and maybe revive myold, tired 8NX!

Edit: Size 15's beat me too the punch, I'm a slow typer!

naked2 said:

The tail (no cap, no contacts) in the one piece Nitrolon body is nothing but a large rubber boot...

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Actually the rubber switch boot has a plastic disc a few mm thick attached to it's inside surface. The purpose of this disc appears to be so that the rubber switch boot remains raised rather than flush with the end of the body.

I would also recommend replacing the bulb. About 9 months ago I had the same issue. I had an original bulb in my 8NX for years. It was appearing dim. I tried my second backup bulb and ...WOW! big difference in output and the hotspot was much better.

In my 8NX, I don't have just a disc on the inside surface of the rubber boot. The insert looks more like a thin disc with a very coarse, fairly thick (relatively speaking) plastic gear with six teeth molded on top of the disc section.

Justin Case said:

In my 8NX, I don't have just a disc on the inside surface of the rubber boot. The insert looks more like a thin disc with a very coarse, fairly thick (relatively speaking) plastic gear with six teeth molded on top of the disc section.

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Yeah that's what I meant - sorry for my poor (simplistic) description.

I would estimate the thickness of this insert to be about 0.2", or about 5 mm.

Ok..on my tail switch I have a super thin almost neoprene disc that is completely worthless. I'm not sure what, if any, purpose it serves. It does not have the "teeth" and is not made of plastic. The rubber boot for the tail switch has no problem standing on it's own but kind of disappointed in the disc. Very cheap! I will try cleaning those contact areas on the spring and inspect the battery area as well. My problem is I don't want to spend the money on a new bulb when I could spend it on a possible upgrade or hopefully a P7 mod from Gene! Not sure if that's possible yet but hoping it will be!!! Start with the small things and work your way up is always a safe philosophy!