Then, my arms melted….

At a neighbor’s tag sale last week, I was reminded of an event from my work for Ace Frehley, which was reinforced by an internet meme today, so here’s my story.

Ace wanted to have the effects modified in the lit guitar. He only ever used a single pattern and sometimes, the controls got bumped while he was playing. He wanted them disabled. John and I drove down to Providence, Rhode Island, where KISS was playing that night. Once we got there, it was apparent that the smoker also needed some work. We hadn’t brought the special wire that it needed – the insulation on ordinary wires wasn’t sturdy enough for the temperatures inside the smoker so Teflon-coated wire was needed - but even it was damaged over time. The closest source for Teflon wire was back in Wilbraham, at Industrial Components Corporation, just down the road from us but a five hour round trip from Providence, and there wasn’t enough time to go back before the show! John called our neighbor’s son, Ronny, who was only too eager to pick up the wire and drive to Providence immediately if it meant that he could meet Ace and see the show from backstage.

Ronny arrived about two hours before show time – plenty of time for John to replace the wiring in the smoker. I couldn’t do anything with the lit guitar before the show as it had to be recharged and there wasn’t enough time to do it twice; Ace always wanted a full charge on the battery or the lights would die before the end of the song. I was hungry; I’d been hanging out at the venue since 10 AM and hadn’t eaten any breakfast before we left the house. It was dinner time and I wanted food! John had promised that we would get a good dinner (I wanted seafood) but there just wasn’t time to go and return before the show. I considered running out for a grinder but John pointed out the crew buffet in a nearby dressing room.

I found a paper plate and napkins, extracted a breast from one of the rotisserie chickens with my jackknife, selected a roll and buttered it to make a sandwich with the meat, and considered the available drinks. The pickings were thin; there were a few cans of Coke but I only drank Diet Coke. A full pitcher of orange juice was covered by plastic wrap and large plastic glasses were laid out nearby. I filled a glass, grabbed a handful of M&Ms from the bowl, and sat down to consume my dinner. 

Ace strolled in, asked me if the juice was freshly squeezed – it was. He poured himself a glass, too, grabbed some chicken, then left to get ready for the concert. I refilled my glass and dumped a handful of M&Ms into a napkin and returned to help John. He wasn’t hungry and asked where the juice came from. John had a piece of chicken breast, too, and informed me that he never consumed anything that wasn’t sealed – drinks in cans or processed snacks – at concerts. It was too late now, so I ignored his concern for the moment. I was wrong.

About 45 minutes later, I felt dizzy. Things didn’t look right. I’ve always seen lines coming from bright lights but the lines started to have more colored highlights. I also saw stop-motion effects, something I’ve never seen except when running a high fever. I knew that I’d been drugged. I went out to watch the concert. The bright lights were fun to watch but Ace, uncharacteristically, wasn’t playing well; he seemed to be tripping, too. I lay down across some chairs backstage for a while but eventually, the lit guitar had been used and Ace had switched to another guitar. I could go to work.

My arms were melting. I kept having to pick my hands up, off of the floor, and it was hard to hold tools and John told me to just pack everything up. I took the lit guitar home to fix it, but I only had a few days before the next gig, so I didn’t have enough time to make it a pretty fix.

Getting into the car, I was afraid that my arms would stretch so far I wouldn’t be able to keep my hands inside. I was sure my hands would be left on the ground, outside the car, and my stretchy arms would get run over by the tires - my hands would be amputated. How would I ever fix the guitar with no hands? John assured me that he wouldn’t let that happen and he got in and drove up home. I tried to sleep on the ride but all of the lights kept distracting me. I watched them with closed eyes. Eventually, we got home and went to bed. My arms were better the next day and I was able to start the guitar job.

I don’t remember exactly what was wrong with it but I think the microprocessor was acting up or not working correctly. After further consultation with John, I removed the entire microprocessor board and supporting devices, and replaced it with an octal counter and a few other components. An octal counter is a device that counts to eight, over and over again. Since the lit guitar had eight sections of bulbs (seven bars plus the border), and Ace only used the pattern that just marched the lit segments in order, lighting one chunk at a time from the neck to the base, then flashed the border, the octal counter was much simpler circuitry than the original microprocessor – a single (small) chip and a couple of components versus a circuit board full of large chips, half a dozen switches, and wires like a plateful of spaghetti. I didn't discard the board and still have the original circuitry in my collection of electronics.

There were a number of switches built into the side of the guitar, fastened by an aluminum bezel that I had made, years before; I removed all of them and covered the holes in the bezel with a single strip of black electrical tape. There wasn’t enough time for me to make up a new aluminum bezel before Ace needed the guitar back for the next gig.

So, when I ran into Ronny at his mother’s tag sale last week, he reminded me of the part he played in getting the smoker fixed. That and meeting Ace were highlights of his youth and no one ever believed him that they had occurred. He introduced me to his girlfriend and I reassured her that Ronny was not making it up. I’m not sure she believed me, either, but at least Ronny felt better that day. Then, an internet meme about acid today reminded me again of how my arms melted when I needed to work, which prompted this blog entry.

Repairing an alarm module in a Bentley

I haven’t written for a while because I’ve been busy with my four part-time jobs! Once of them has me working at Robison Service, listing items for sale on eBay and occasionally, doing other odd jobs. 

John has written in his car blog several times, lately, about the problem of Bentley and Rolls Royce electronics modules and the batteries on them that start to leak over time. This alarm module came out of a 1996 Bentley Continental. Bentley only made a few hundred of these cars and is no longer making components for them.  The controls are easily damaged when the batteries inevitably begin to leak and Bentley’s stock of new replacement units has been depleted. Since these control units are no longer available from Bentley, there is no choice but to repair them when they go bad, although some preventative maintenance of replacing the batteries is preferable to trying to fix one after it has gone bad. This one has gone about as bad as they get. 

 

You can clearly see that the dark blue battery in the middle has leaked badly, causing a great deal of damage to the top of the circuit board and destroying copper paths. There is a second battery, teal in color, in the lower right corner. This one had also leaked and damaged traces, although not in such an obvious manner as the dark blue battery. I’m pretty good with electronics and I have the patience to debug such disasters, so John asked me if I could try to repair it.

The first thing I did was unsolder and remove the batteries carefully, wearing nitrile gloves to keep the leaking electrolyte from burning my skin. Leaky batteries and their detritus can be very nasty.

With the batteries removed, the damage is more apparent. I used a Sharpie to mark the battery specifications on the board, in case I lost the piece of paper that I had used to record their information. I like to put vital information in more than one location because I lose paper.

You can see that there are even traces missing from the bottom side of the circuit board, where the electrolyte leaked through some of the component holes in the board.  

I wanted to remove the blue connector on the bottom side of the board, to make sure there weren’t any damaged traces under it, but I didn’t have the proper unsoldering tool. I looked carefully with a flashlight and my magnifying glass and decided that I might not need to remove it, so I left my final decision about it for later.

Next, I needed to know what kind of electrolyte remained. Electrolyte can be either a strong acid or a strong base. It depends on the type of battery. The dark blue battery was Nickel-Cadmium (NiCad), while the teal one was nickel metal hydride (NIMH). I went to Wikipedia and looked up both types of battery. I discovered that they both utilize a basic electrolyte, so my first plan to neutralize the remnants with baking soda wouldn’t work; I needed a weak acid. I chose vinegar because it is safe and I had a gallon jug of the stuff in my pantry. I raided the bathroom closet for a big box of Q-tips.

I poured a bit of vinegar into a small cup and dipped in a Q-tip, then lightly scrubbed at the stain. It bubbled vigorously. I discarded the Q-tip and repeated the process until I had cleaned both sides of the board, a process that took several hours. The stains only bubbled in a few places and only the first time I wiped them but, eventually, the tarnish also began to come off. As I scrubbed, I repeatedly moistened the edge of the blue connector (on the bottom side), encouraging a bit of the vinegar to slip under it, to neutralize any possible electrolyte remaining under the connector. I used more vinegar swabs to clear off the dusty bits from components on the adjoining circuit board. I was patient because I wanted every speck of electrolyte cleaned off of the board before I tried to initiate repairs.

Now that everything was nice and clean, I was ready to start tracing the paths of the damaged copper foil. I scratched at some traces, to gauge how deeply they had been etched by the electrolyte. Some came off entirely. I started by trying to replace the traces, but gave this up when too many traces turned out to be only a few molecules thick - that's when I started to systematically scratch at them with an exacto knife, to test their solidity. 

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I used 30 AGW wire to replace most of the traces. For the power traces, I used a heavier gauge wire. The small blue rectangles are capacitors; the larger black components at the bottom are diodes and the bigger black rectangles are relays. There wasn’t any logic, to speak of, on this board, so I was fairly sure that if I just replaced the broken connections on the board with wires, the board would function properly - individual components are inherently sturdier than logic components, which contain many interior components. Some traces moved from one side of the board to the other via little plated holes; I decided that merely connecting their ultimate ends was a more efficient means of repair.

For some of the top traces, it was easier to just connect the components on the bottom of the board.

I couldn’t find exact voltage replacements for either of the batteries at Radio Shack. I needed a 6 volt Ni-Cad and a 4.8 volt NIMH. I did find 3.6 and 2.4 volt Ni-Cads and 2.4 volt NIMH batteries. I connected two batteries (of the same technology) in series to add up to the correct voltages (the amp-hours were a little higher than in the originals but that shouldn’t create any problems). All four replacement batteries were meant for cordless telephones. I taped the pairs together, connected one red to the other's black to add the voltages in series, cut off the remaining connectors, and soldered the packets in place.

Once the unit was folded back together and the clips safely secured, the module was ready for Buddy to re-install it in its car and test it.

 

It worked properly. Another problem solved.