Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Thanks, Bruce!

Another thing I worked on was the method for insulating the heater terminals. The original insulators consisted of stacks of very thin mica washers, fitted to the counterbores surrounding the terminal holes in the base. Many of the washers were cracked and bent, and I just didn’t have a lot of confidence in this method. I decided to make some insulators from Garolite G7 rod. This is a high-temp insulating material often used in industry for just such applications. Here is a side sectional view of what I was planning:

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The G7 material is hard and powdery and not very pleasant to machine, but I feel it serves as a more positive insulator than the stacked mica washers. Here is what the finished insulators look like:

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And here is how they look with the terminals installed in the base:

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Here is a view from the underside, with the heater re-installed:

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Here are some pictures of the finished engine. Note the throttle and whistle handles. These originally had cracks and badly flaking paint. I originally thought that they were made of wood, but they are some kind of plastic. I removed the paint and filled the cracks with epoxy. I decided not to repaint them, as they are already red (dark red), so I just gave them a light polishing, and re-installed them.

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The pressure gauge was an afterthought, though I’m not certain if I’m going to keep it.

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(to be continued...)