December started on a Friday. It was also our first day this winter helping at Way of the Cross in Harlingen. They have two drive through food bank days per week, Wednesday, and Friday. Juanita helps with those and in the warehouse getting ready for them.
Stuff gets donated to the ministry. Most gets given away. Some is used in the ministry or gets sold to support the ministry outreach. I mostly work with Byron, my usual work partner here. He does what ever is needed in terms of facility repairs or prepping stuff that comes in so that it can be used or sold.
The first item I helped with was a Miller Big Blue welder from the 1990’s. It is driven by a lovely little Duetz diesel engine. The engine didn’t crank over when it came into the ministry. Byron troubleshot that problem. Somebody had put a new starter on it with the incorrect toothed gear. After swapping out the gear the engine started right up. That must be the problem! Nope. It only sparked a bit with a welding rod and the outlet from the generator circuit was similarly limp. There, but only just there for both welding and service outlet. Shoulda been my first clue but I’m getting weeks ahead of that story.
Byron did some work on it, then he had to be away for a while. Other fingers got into the machine. And that’s in the last month. Who knows what various fingers have done in the last thirty years. There’s a good circuit drawing on the side panel. I took a picture and started studying. I perused welding forums on Friday and off and on during the weekend. I’ve never worked on a welding machine before, but the electrical principles are not that different than other equipment I have worked on.
On the following Monday I went to start up the welding machine and held the switch in the start position too long. Oops. I blew up the starter. I watch Byron take off the starter. I take it to the starter repair shop. I expect them to declare it dead and gone forever but they tag it with my phone numer and say they will call me when it is ready.
On Tuesday, Byron and a couple of others go to Oklahoma pick up a truck somebody donated. I’m on my own for a few days. I study the welding machine a bit more and do some lighting and hydraulic repairs on a forklift. Byron had taken the hose reel apart and ordered the parts. The seals arrived so I installed them. It was like being a first-year apprentice again.
On Friday I went to the starter shop to see why they hadn’t called. The starter was dead and gone forever. They sold me a new one and made sure it had the correct toothed gear. I watched Byron install it. We fired the machine up and tried a few things which didn’t change things a bit.
I did more study over the weekend. The next week we tried more things. We cleaned the slip rings and I took measurements both running and stopped. A long, detailed letter to Miller tech support resulted in an obvious possible cause which we had eliminated. We dove deeper and found a reversed bridge connection from some fingers probably long ago. Not the problem. Probably would take a bit of the edge off the welding side at peak setting but not kneecap the output.
Finally, we tested a component that would have been near the top of my list when I was doing electronic repairs in my prime. It was one of the few things that would affect both welder and generator output. We tested the diode between the battery and the excitation circuit. It was shorted. That held the excitation voltage at 14 volts. We took the diode out of the circuit and the machine worked once the excitation voltage wasn’t suppressed. Bittersweet victory. Satisfaction at finding the problem. Frustration at taking weeks to do it. A new diode assembly was ordered and installed the following week and the machine can be cleaned up ready for sale.
Another thing that has been donated to the ministry is a SWAT truck from a city in Tennessee. It had been used as a mobile command center. It is a massive box truck retrofitted for the purpose. The truck is already tall. During the retrofit they added two air conditioning units to the roof. That made it taller. Taller than the structure somebody tried to drive under. This damaged the ceiling and the integrity of the water seal on the roof. The truck suffered from significant water damage. They started repairs but bailed when they realized it would not be economic. It ended here as a donation with the “T” whited out. It reads “Chattanooga SWA” on the box now. Once stripped and repaneled inside it will make a great box truck.
Byron removed the 15KW generator from under the truck. Somebody built a frame. We painted the frame and installed a muffler on the motor. Then we reinstalled the bumper and started gutting the interior of the box.
On the last Friday before Christmas. Juanita helped in food line, especially sorting vegetables. I marked stud locations while Byron and his visiting brother John went to Home Depot for lumber, OSB and plywood. When they came back, they pounded down nails on the old studs while I cut lumber to support the former AC bays on the roof. The original convertors cut the ribs to accommodate the AC and used the ceiling rafters to support the units. Trauma and rot destroyed the old rafters.
Next week the ministry will hold no food bank drive through. It will concentrate on the Big Feed, an event over the border in Matamoros, Tamaulipas, Mexico. About a hundred volunteers will come down to the valley and cross over the border to help. Our travel insurance limits our travel to Tamaulipas. We will stay on the US side of the border. Juanita will help with meals for the volunteers. I will help with that a bit and putter on the SWA truck a few hours a day.