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Subject: Fire vs JBR

Fire vs JBR

From: Neon John <jgd_at_johngsbbq.com>
Date: Sun, 05 Aug 2007 23:56:35 -0400

JBR wins!

Several months ago I retired and moved to my cabin in the mountain fishing settlement
of Green Cove near Tellico Plains, TN. Not content to just laze around doing
nothing, I opened a BBQ restaurant out of my custom-built concession stand trailer
left over from my restaurant days. Something to do on the weekends to stay busy and
meet people.

This afternoon I was sitting at the counter of the general store where I have my
trailer located, chewing the fat and generally enjoying the afternoon. I saw a cloud
of smoke and thinking that my BBQ pit might be getting too hot, went out to look.
Smoke was pouring out of the roof of the trailer. The electric deep fryer's
thermostat had stuck and started a grease fire.

The trailer is almost air-tight so the fire was oxygen-starved and latent. When I
opened the door, pretty much everything chest level and above burst into flames. Not
good. I grabbed a water hose, cracked the door and started hosing. Not seeming to
make any progress, I grabbed a 20 lb dry chemical extinguisher and fired away.

The fire just... stopped... burning....

That was the most impressive job of fire snuffing I've ever seen. A 2" line could
not have done as well. It took another 15 minutes to snuff all the hot spots and
cool things down.

One of the first things I saw was my precious JBR V1 laying on the floor in water and
covered with smoke and dry chemical. I'd been using it to play tunes through some
outside speakers. DAMN!

I yanked it up and yanked the batteries out. Many times dunked gadgets can be saved
if the power is removed so electrolytic action can't destroy PCB traces. Did I
mention that not being able to do this is yet another reason I despise built-in LiIon
batteries?

I hosed the thing down through the battery compartments right there on the spot. Then
I played Archos Paramedic and raced back to the cabin. I quickly took the thing
apart. I removed the hard drive, misted it with distilled water in a spray bottle,
wiped it down with a towel and set it in front of a hair dryer running on low to dry.

I made up a bowl of warm water and gentle detergent and washed the JBR PCB assembly
and rinsed it first with warm distilled water and then pure grain alcohol. The
alcohol displaces trapped water in the switches and under components. It then got
the hair dryer treatment.

After it was dry and while the hard drive was still drying I applied power to the PCB
assembly. Never have I EVER been so happy to see the RockBox logo! It booted to the
ATA -1 error as it should have.

I gave the hard drive a good hour's drying in front of the hair dryer, let it cool,
stuck it back in the JBR PCB assembly and applied power. IT BOOTED! And played! My
blood pressure dropped a couple dozen points.

Before I installed the drive I inspected the PCB assembly under a stereoscope. In
just a few minutes the thing was wet before I got the batteries out, some
electrolysis had occurred around the "ON" switch which always has power on it and the
area around and just to the left of the "down" arrow switch. Probably an energized
trace there too. I cleaned the white gunk off, carefully inspected the board and
observed that no actual traces were damaged, only the solder. Whew!

So. I'm sitting here writing this up and listening to my JBR. The plastic is a
little stained from the smoke but other than that, all is well. There was enough
conductive crud on the batteries to have drained them between then and now (about 6
hours) but they cleaned up and quick-charged fine. I'll have to wait and see if
there is any residual current leakage/fast self-discharge.

I learned or confirmed several things:

* The JBR is one tough cookie. But we knew that.

* Getting the battery out of a dunked gadget NOW will usually save it. Gadgets with
soldered-in batteries and/or with backup batteries on the PCB probably won't be so
lucky.

* A soap and water wash followed by distilled water and then alcohol rinse salvages
dunked electronics.

* To wash away the smoke and acids you have to be able to get the thing apart
quickly. Hear that, Apple?

* Thermostat contacts stick shut and sometimes the safety backup thermostat does too.

* Even a little grease makes a big fire.

* Dry chemical extinguishers are just flat impressive. Everything in the trailer
that had been the least bit warm was coated in the stuff.

* That fire extinguisher that you hang just inside the door so you can reach it will
be unreachable when you need it.

* It sure is nice to have a second BIG extinguisher in your truck.

* From my previous experience with a fire, I knew that getting the smoke out and
getting equipment washed down before the acidic smoke could set would save lots of
stuff. It did. Two $700 12 volt operated portable freezers were probably the most
valuable items saved. I had a smoke extraction fan going while things were still
sizzling from the heat.

* money is easy to launder. Just put it in the washing machine, gentle cycle and
some detergent. Then toss it in the dryer and it comes out good as new :-)

* A couple weeks ago someone backed into my car and caved in a door and left the
scene. Today, this. When is that black cloud hangin' over my head going to go away?
What a way to start a retirement!

John

--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Remember, amateurs made the Ark, professionals made the Titanic.
Received on 2007-08-06

Page was last modified "Jan 10 2012" The Rockbox Crew
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