The work continues on the expansion of the layout into the alcove area and I've recently installed the joists on the L-girders. The weights are on the benchwork at the right are there because of a nasty twist caused by warped lumber. Once I attached the benchwork to the floor it won't be a problem.
I've never been happy with how flimsy the joists seemed when the risers are attached as the risers act as a "lever" to twist the joists from side to side. I don't like benchwork that isn't rigid, so I added stiffeners to the joists and they are much more rigid now.
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The stiffeners are made from 5/8" sandply plywood that I cut using my 50 year old DeWalt radial arm saw. I had a bunch of scrap plywood, so other than the cutting time it was easy.
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Here is a closer view of the joist and the stiffeners. The joists are attached to the top of the L-girder from the bottom using 2-1/2" coarse thread drywall screws screwed into pilot holes to avoid spliting the plywood. I attached the stiffeners using 1" coarse thread drywall screws without using glue. I may need to move things around a little bit for turnout motors, ect. and I wanted that to be easy to do.
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Here's a little closer view of the stiffeners and joist showing the mounting screws.
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Some might say that this is "over-designed" or "over-built", and that might be true; however, I'm all for "over" when it comes to a strong, stable benchwork.
Stay tuned for the next installments which will include cutting a hole through the wall, adding risers, sub-roadbed, and alike.