SF A2 driver removal - DONE!! w/pics

troller_cpf

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Is there any possibility of removing the driver from the body of a SF A2 Aviator?
I've got a spare old style 4-flats body with no driver inside and I wanted to change the current round body with that

thanks!!
 
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leukos

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Re: SF A2 driver removal

There is no easy way to remove it. It can only be removed from the bezel. There are three black plastic tabs that hold it in place. If I were to pull one out again, I would probably use my dremel and just cut those black tabs so it falls out freely. Then I would pot the pcb for strength, then glue it into the new body.
 

troller_cpf

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Re: SF A2 driver removal - DONE! w/ pics

I did it!
I decided that changing the body to the old style 4-flats was worth the effort and the ruining of the inside of the A2.

I had to brake off the 4 (not 3) plastic pins that hold tight the driver in the bod, using my Victorinox.
Then I pulled it out of the body and placed it in the new one.
Problem is that, even after having removed the 4 plastic holders, the driver is still very very tight inside the body. As a result, while pulling it away (gently), I managed to brake one of the FOUR negative contact pins on the back of the driver around the center positive spring.
I decided not to solder it back (I'm not very good at this) and the "new" A2 still works fine, even with only 3 pins.

Following up are some pics:

Current A2 just after the removal/braking of the plastic driver caps
1001w.jpg


1002h.jpg



The Driver itself
1004u.jpg


1008m.jpg



The current body (above) I want to replace with the new 4-flats Old Style (below), and driver in center
1010z.jpg



The "new" old A2 completely disassembled (except for the tailcap):
1013r.jpg



Everything installed in the old style A2... it's much better this way!!!
1016q.jpg
 

mwaldron

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First one I've seen on how to remove the driver.

My informal testing is complete and the newer round bodies contain drivers significantly more efficient than the older 4-flats so this swap is something that's a reasonable idea.
 

leukos

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Congrats! I did the same swap a few months ago. The A2 pill is fragile when you try to remove it. I think I had two wires I had to resolder. I didn't think to cut the tabs, and tried to remove it by force from inside the battery tube, it just resulted in damaging the plastic sleeve. Thanks for the pics for any future modders.
 

KeyGrip

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My informal testing is complete and the newer round bodies contain drivers significantly more efficient than the older 4-flats so this swap is something that's a reasonable idea.

Details, please :poke: . Are we talking brighter at a given runtime, longer runtime at a given brightness, or a balance of both?

:popcorn: :popcorn:
 

KeyGrip

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What got my attention was he specifically mentioned the newer drivers were more efficient. Depending on the tests I suppose he could take more efficient LEDs to mean a more efficient driver, but I'm curious to know more because I'm deciding between buying an older flat-bodied A2 and a newer round-bodied one.
 

ejot

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Very nice writeup - thanks! I'm sure I have a four-flats A2 body somewhere in my parts stash and will definitely swap the guts from one of my round bodies.
 

mwaldron

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Details, please :poke: . Are we talking brighter at a given runtime, longer runtime at a given brightness, or a balance of both?

:popcorn: :popcorn:

it may simply because the new A2 has a more efficient LEDs :)

Sorry for my delay, I have been mostly off of the forums for a few days.

You can't really increase brightness in the regulator without changing the design of the bulb. Surefire has designed the A2 to work with MA02 bulbs, so they have to keep in spec with that bulb's capabilities. The regulator in the A2 is a constant voltage regulator, and thus the only way to increase the brightness is to design a bulb to be more efficient at that voltage (LF HO-A2) or to overdrive an existing bulb (Strion).

The 5mm LEDs are lost in the noise of any calculations, they just don't matter that much sitting next to that big old fireball. They're also not part of the regulator circuit.

I have not done any testing on my bench supply, everything here is observed behavior and no real numbers have been gathered or analyzed. Thus it is subject to be completely wrong, but it is what I have observed.

I have a fairly old A2 4-flats (red) that I use around the house, and I recently acquired a really new A2 round (yellow-green) that I was playing with because, well, it's new.

I have always preferred the 4-flats design, I think it looks better, feels better in my hand, and I like the 1/2 on incandescent stage that shows up when the batteries need replaced. The 1/2 on stage, often called the sickly yellow beam, is what this is all about. I've never seen any of my round A2's exhibit this behavior, but I never really thought about it either.

I have observed that you can often double-tap a 4-flats A2 to change it from the 1/2 on stage to the normal incandescent. Generally, when I can no longer double-tap to get the normal beam, I change my batteries.

My Red A2 needed new batteries, and I gave it the two from the newly acquired YG. I was only really interested in the YG A2 for the YG leds

I tossed the old spent 123's into the YG to play with. The incandescent bulb worked. That's not to unusual to get a short burst after a rest period, so I didn't think much of it. It kept working though, so I started using it. I used it for several more days (just taking the dog out, etc) before it finally gave up. When it gave up there was no 1/2 on state, it was just dead. The 5mm LEDs, of course, continue to work just fine.

The conclusion I draw from this, is that the newer regulators are either more efficient, or have their minimum voltage threshold set lower.

An equally valid conclusion to draw from this is that I just happen to have a particularly bad old 4-flats A2 and a particularly good new round one.

I have enough variety of A2's that I can sample several but I just have other projects I'm working on at the moment and it hasn't been that big of a deal.
 

leukos

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I have observed that you can often double-tap a 4-flats A2 to change it from the 1/2 on stage to the normal incandescent. Generally, when I can no longer double-tap to get the normal beam, I change my batteries.

I have five 4 flat A2's, one of which has a driver from a round bodied A2, but I have never witnessed the behavior you are describing.
 

mwaldron

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I have five 4 flat A2's, one of which has a driver from a round bodied A2, but I have never witnessed the behavior you are describing.

You've never seen the 1/2 on stage (often referred to on CPF as a sickly yellow beam) on an A2? Strange...
 

leukos

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Oh, yes, certainly, but not the double tap to switch between the two as if it had two modes.
 

Illum

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You've never seen the 1/2 on stage (often referred to on CPF as a sickly yellow beam) on an A2? Strange...

some square A2's drivers will cut out the incandescent while the same batteries in a round A2 will last a bit longer. I have only witnessed the sickly orange color if I left the incandescent on with partially dead batteries. when it comes to that and the light is turned off, upon turning on again the xenon will stay off telling me the driver wants new batteries
 
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