ARC LS Repairs

[Carpe Diem]

Hi Guys...

Thanks for your kind thoughts!

As soon as I start my new gift list, I`ll be sure to put all of you on it!

 

[this_is_nascar]

Peter,

Is there anyway for a typical user to determine whether or not their LS suffers from the flex-failure? If so, is the failure something that can be corrected by the user?

 

[Gransee]

Primary symptoms are that when turning the head to turn on the light, it initially comes on with a little pressure but further tightening causes the light to go out. There is no field service for this yet.

Peter

 

[Gransee]

Today, I tested several methods to revive a unit suffering from the flex failure. Here's my findings so far:

1. Solder blob to back of PCB idea.

This involves placeing a solder bridge between the ground of the PCB and the housing. It can be done without dismantling the head. The retainer does have to be removed and a new one installed in its place after the service.

I started with 5 bad units and got everyone one of them to work - initially. Mike came in and torqued them all quite hard and made all of them except two fail again.

2. Remove Bezel approach.

With this fix, I removed the bezel and tweaked the insides. This was more effective than the solder fix above but required more work. I tried this on 3 units and got all of them to work 100%, even with battery squashing torque.

First, you have to remove the bezel. Loctite holds it in place so I tried several methods to break the seal. Both involved heating the head up to about 200+ degrees. One method involved placing a soldering iron against the head and the other method involved dropping the head in boiling water like an egg.

About half the units I tried loosened up by the above methods. Some would not budge.

Once the bezel is off, I removed the PCB from the bezel. Next, I ground off the HA around the bezel lip that faces the PCB. A dremel did well on this. I also took some of the HA off the bezel threads as well. Next, I applied blobs of solder around the upper ring of the PCB so it would be sure to make contact with the bezel.

Finally, I reattached the bezels and stressed test the lights by placing the 2AA pack on and turning it as tight as I can. All the units that made it to the bezel step worked 100%.

It is a real bear to get the bezel off though and I am looking for an easier way to fix all these bad units.

More to come..

Peter Gransee

 

[fasteddie]

Peter, I tried the solder blob on the back of the pcb fix on the amber we talked about. It worked, although I've had to go back and redo my solder work, once to fix my sloppiness,and the second time because the light was flickering. I've torqued the head pretty hard with the 123 pack, and it seems good so far. Also tried the drop test and it still worked. I cut a notch in the retainer to compensate for the solder blob and that seemed to make it work more reliably. So far so good. I'll email you a picture. Won't post it here unless you give it the seal of approval.

 

[Lantern Jack O.]

Doh! My HD cyan started to flicker tonight, and actually died a couple of times.

I simply wiped the + contact on the battery, and the bottom of the PCB, and it is not flickering anymore.

Looks like it was just simple oxidization in my case. All the same, it's very good to know that Peter is coming up with lots of good ways to cure the flex problem.

--Edit---
Problem came back again the next day. The symptoms are consistent with the flex problem. Peter, this one's coming back for some of your TLC.

 

[Willmore]

Ahh, I don't get that problem. I use some PCB mount 123s that I got cheap. If I rip the pins off of the ends, there are sharp little patches where the spotwelds were done. Perfect self-cleaning contacts.

My SLSs don't flicker. I do need to get rid of this '123 happy' retainer. Give me a first generation thick'ol retainer any day. I was never bothered by battery rattle in the 2AA tube with the old retainer.

Then again, my old SLS never had a problem with 123s to start with.