Boller & Hodge Bridge Shoe

Boller & Hodge Standard
I found a drawing of a bridge shoe that looked like it would work for what I needed. (meaning it was simple enough). I found this is a book titled “Types and Details of Bridge Construction: Plate girders – by Frank Woodward Skinner and published in 1906. On page 158 there is a nice drawing of a Boller & Hodge standard bridge shoe along with the following:

Boiler & Hodge. — Messrs. Boiler & Hodge, New York, have designed standard sets of cast-iron shoes and pedestals for plate-girder supports which have been used for a large number of railroad bridges. The smallest has a base of 16 in. square and the lengths of the sides vary by increments of 4 in. They are designed to distribute the loads uniformly on the base and to reduce the intensity of pressure to 200 lbs. per sq. in. on the concrete on which the pedestals are assumed to be supported, or the equivalent cement mortar with which they are leveled up on stone seats. They are made of tough gray cast-iron, which it is specified must be strong enough for a sample test piece 1 in. square and 12 in. long to bear a center bending load of 2500 lbs. The thickness of the metal varies from 7/8 to 1-3/4 in., and all angles are filleted with a radius of 1 in.
Short -span girders have both ends fixed and seated on single-piece pedestals with planed flat tops supported on longitudinal and transverse vertical webs. The bottom flanges of the girders are secured to the pedestals by four 7/8-in. bolts, and the pedestals are fastened to the masonry by two 1-1/4-in stone bolts 15 in. long. The largest size is 36 in. wide, 26 in. long, weighs with bolts 825 lbs., and has a capacity of 185,600 lbs.

The point of copying and pasting all of that is – this is good info for the modeler. We are of course going to modify everything to fit our modeling – the changes we have based on the materials we have to attempt to replicate it. The important thing is that this is starting point we can work toward. We have dimensions, bolt sizes and so on.

Version 1
This the my first attempt – Part II. This was early in my using Sketchup for design – and the somewhat crude design reflects that.
Version 2
This the my second attempt – Part III. This version is an exact copy of the original design.
Version 3
This is a simple variation on the original design so it would print in WSF (White Strong and Flexible). This material has a minimum wall thickness of .7mm – which increases the thickness but not that much really. The reason for wanting to print the shoe in WSF is that the material is a VERY strong nylon.

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