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Tuesday, January 22. 2013Preventing lightning damageLightning protection is a very important aspect of an overhead traction power system. Substantial damage can occur without such protection. To avoid such damage lighting arrestors are installed at regular intervals. Arrestors are like a pressure relief valve for electricity. If the voltage (pressure) gets too high, the arrestor drains current to ground. Most damage caused by lightning is the result of it seeking a path to ground. The severe damage is the result of normal power current following the path the lightning surge created.  Hole through wall of barn 8 behind traction power disconnect caused by lightning and subsiquent power arc.  Feeder insulator punctured by lighting  AGC hanger damaged by lightning induced power arc. At IRM I use metal oxide varistar (MOV) arrestors on both the A/C and D/C systems. These provide State-of-the-art protection. The arrestors are rated for the application voltage 175 Vac, 3KV ac, 1KVdc etc. All MOV arrestors function the same way. In this story we will deal with D/C arrestors. The MOV material conducts current at high voltage and has a high insulating value at low voltage. This "discharge" voltage is dependent upon the thickness of the MOV material. The thicker the material the higher the discharge voltage. When a surge exceeding the maximum continuous operating voltage (MCOV) rating reaches the arrestor the MOV material (valve) becomes conductive and discharges the surge to ground. As soon as the surge is gone and the voltage returns to normal the valve seals and becomes insulating again.  1KV D/C lightning arrestor installed on bracket arm pole. Note use of glass insulators mounted to bracket arm to support arrestor tap.  1KV D/C lightning arrestor protecting pit lead feeder. The most important part of an arrestor installation is the grounding. Grounding is simply a connection to the earth. The ground connection must provide a low resistance connection to the earth. There are many methods to accomplish this. A cable or plate can be buried or rods can be driven. Through experimentation, I have determined that four 5/8 inch by eight foot copper clad ground rods coupled together and driven to a depth of 32 feet, work best in our soil. This type of installation consistently provides a resistance of 13 ohms or less. Driving more rods to increase the depth did not lower the resistance enough to justify the effort.  Setup for driving ground rods. To drive 32 feet of ground rod I use an electric pavement breaker with a special tool bit for driving ground rods. The breaker is light enough so it can be thrown on my shoulder and carried up a ladder then placed on the ground rod. A hardened steel cap is placed on the rod to prevent "mushrooming" the end. The rod is driven, then the next rod is placed in position. The rods are connected together using a threadless coupling. The hole in the coupling is tapered so that they are wedged together tightly when pounded into the ground.  View showing threadless rod coupling. Note use of wood ground wire moulding. A #4 solid covered copper wire is used to connect the arrestor to the ground rod. The connection at the rod is made with a special clamp called an "acorn". It has a special "torque head" bolt. The head of the bolt is designed break or shear off when tightened to a predetermined torque value. This ensures a tight tamper resistant connection. The ground wire is covered with wood molding. This protects the wire from damage and protects both linemen working on the pole and people on the ground from contacting the ground wire.  groundwire connected to rod with acorn type connector. Head of bolt breaks off when proper torque is reached.
Monday, January 21. 2013Wood Shop Update - January 19, 2013Photo Update: This is becoming my new hobby - BEAT THE CAMERA. I used a new camera this week and hopefully the pics will be better. But the software with the new camera seems not to load properly on my computer with Windows XP OS, in spite of the disc saying it will. Of course no tech support available on a weekend. So, after a three hour workaround I think I have the images out of the camera. I figured there would be a learning curve so my backup plan was to use a USB memory card reader, but even that failed to work with the SDHC card. UGH! On to the NEWS - - -  Windows More progress to report on new windows for the Chicago Great Western X 38 snowplow. Here, Victor Humphreys and John Faulhaber get ready fire up our BERLIN sander and run eight frames through. This is the BEFORE pic, and perhaps you can see some of the glue lines and squeeze out.  The AFTER Windows As usual there is always drama when using century old wood working machinery. In the end all windows were sanded smooth and finished. But the machine will need some attention in coming weeks. We knew the sandpaper on Drum Three was about at the end of its life, and now that is no longer a question. Time for a change, which is not a trivial investment of time and energy. You do not have to be a cabinet maker or talented woodworker to do this. Any skilled backyard mechanic may help. Related to shop upkeep was the changing of blades int he planer and a thorough cleanup of the innards. This stuff does not happen by itself.  Next You may have noticed that the side stiles of the completed frames looked too long, to have had tails on the ends. This is intentional, part of the process. Here Victor and William Peterson have helped to trim them all flush. The final step here was to run a six degree bevel on the bottom member of the frame, to help drain water and to fit the angle of the new sills in the car.  Continuing We continued the process with William Peterson doing the fussy work and cleanup of the frames after sanding, and Rich Witt starting to cut and fit the newly made quarter round beading that will be used to retain the glass.  Sign Boxes Eric Lorenz has two of the original sign boxes out for restoration and installation in Cleveland Transit System 4223. To get the side windows properly installed, there is a great assembly of parts and pieces that all have to fit in concert before the trim work can be completed. Who would have designed something THIS way?  More Parts We were all happy to see Lorne Tweed back in town and that he has his priorities right. Early after his return to the midwest, he was on site and working on the 4223. He is priming one of the special trim pieces, a one of a kind item to cap the window post immediately behind the motorman's position.  Grab Irons Victor explains the steps to make new caboose grab irons to William Peterson. We made a plywood template to get the round bars bent correctly, and now will use that to add blocks for it to serve as a welding jig. It as all part of the game, plan the work and you are seldom disappointed.  Third Rail Beams Keith Leitsch and Randy Hicks were caught in the act of working on new third rail beams for Chicago Aurora and Elgin car 36. The first task of getting the new wood and preparing the blanks for the beams is done. Now, comes many hours of sawing away parts of them, drilling many holes, cleaning and painting the hardware items, and installing them. Stay tuned.  Workplace Improvements Rich Witt is at the new and improved, better equipped Engineering work station. He is preparing working drawings for two new windows for the B&M cafe car, and it almost looks like a real engineer from the 1920's. All he needs is a green eyeshade and gaiters for the shirt sleeves. And of course lots of other work and activity including three new window sash fitted and glued for Chicago Rapid Transit 1024 (by Tim Peters).
Sunday, January 20. 2013"SMILIN JACK"...Project Update...BM 1094, January 2013
"Smilin Jack" Biesterfeld says... "Progress is our......" If you're old enough to remember this saying it's from an advertisement for General Electric in the early television days. It could well pertain to 2012-2013 efforts on the Boston and Maine#1094 wooden cafe-coach.
 Jack is not smiling He is busy working in the kitchen  One large oil tank to be removed What a dirty nasty job  small oil tank already removed by Mike Ray and Mark  small tank removed The wall stripped and varnished  another view of the restoration progress on womens bathroom wall where small tank was  sign painter at work WOW  Now it official Its a Boston and Maine cafe coach |
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Comments
Fri, 03-29-2024 21:26
We're slackers and spend more time working on the equipment in the shop than keeping all you readers updated. We'll work on it, but I'm sure updates [...]
Thu, 03-14-2024 08:02
What happened to the Department Blog? It's been over 2 years and I still regularly check for updates, but nothing comes...
Mon, 12-27-2021 16:28
Happy New Year to all the Departments at the Illinois railway Museum! Thanks for all the good work you do in railroad preservation. Ted Miles, [...]
Wed, 10-13-2021 13:33
Was the CB&Q 1309 every transported to IRM?I’ve been reading old issues of Rail&Wire and the car was mentioned several times.
Mon, 06-07-2021 22:40
I was wondering if in the model layout display what scale would you guys be using and would you be displaying model train history as well? Just [...]
Wed, 06-02-2021 17:27
Nice to see 428's cab back on. Looking forward to when it is operable!
Tue, 06-01-2021 16:47
I hope the work will continue on the UP #428. Now that they are the museum's connection to the national railroad network; she would be very [...]
Sat, 04-17-2021 23:07
What is the status of 126, the Milwaukee Buffet car that is in S. Dakota? Any guess on when or if it will get to IRM?
Wed, 04-14-2021 21:09
Perhaps it is time to scrap the remains of the c, B & Q 7128 to make room for the Villa Real. Ted miles, IRM member
Wed, 04-14-2021 15:26
Hi IRM my name is Jason and I was wonder If you guys would be willing to save a CN Dash8-40cm they are currently being retired by CN and being [...]
Fri, 04-09-2021 19:56
Bear in mind that the Nebraska Zephyr is an articulated train set, so cars cannot be inserted at will. Although cars and/or a second engine could be [...]
Wed, 03-31-2021 11:37
I believe Silver Pony is currently on the back burner, and has been put into storage in one of the barns. The car needs a lot of work done to it's [...]