Quantity Surveying

As we near the end of bench work construction, it’s time to start thinking about the track. For some reason, I don’t feel much like working on any of the actual construction projects this evening. So, I whipped up a quick spreadsheet to estimate the quantities of things like ties and rail and so on.

If this were a larger layout, I might not want to do that as it would immediately point out how much I am spending on the project. Better to get that news one trip to the hobby shop at a time. However, this is a small layout, and it’s worth getting all the materials at once, and ensuring I have enough of each of them.

To start, I measured the length of every piece of track on the plan. I measured from the points of turnouts, rather than from frogs or fouling points. Some things, like spikes and rail go all the way to the points. Others, like ties, stop short of the frog.

Then I calculated the total length of track in inches and multiplied by two since I’m not building a monorail, and divided by 36 to get the number of lengths of rail. Pembroke gets 36 lengths of rail.

The other materials are the same as the prototype, and so, I converted to scale feet. We know that the ties were on two-foot centers, and so, I divided the total length by two. Then I subtracted twice the number of ties in the turnouts, which you can get from standard turnout diagrams. Why twice? Because, I measured lengths all the way to the points, so I effectively measured the turnouts twice. There will need about 1400 regular ties and 500 turnout ties.

The Pembroke Southern was laid with 56 lb Carnegie Steel rail. It would have come in 33 foot lengths so it could fit in a 34 or 36 foot car. So, I simply divided the number of feet of rail by 33 to get the number of joints. There will be almost 300 joint bars on Pembroke.

The real shocker is the number of spikes. At four per tie, accounting for turnouts, there will be over 9000! Well perhaps I don’t need four spikes in every tie!


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