Re: 3-3-3 ends


Tom Madden
 

On Mon, Jan 6, 2020 at 01:06 AM, Staffan Ehnbom wrote:
Hi Tom,
Would you tell us how wide the West Rail casting is? Surprised to see the tack board seems to be cast in place.
Staffan -

Well, they are 30+ years old. Richard was even using a dot matrix printer for his labels.

The attached photo shows the dimensions and a comparison to ends from an InterMountain 10' 6" IH boxcar. They're pretty close to interchangeable if you remove the rivet strip at the top of the West Rail ends.

Richard made his parts to fit Athearn blue box car bodies. The material is filled polyester, the same as Al's early kits but Richard chose a red colorant rather than gray. That's a "fast" casting resin, cures quickly and generates a lot of heat. You can cast a lot of parts in a hurry, but if you don't let the mold cool off between pours it will heat up and expand and the parts will get larger and larger as you go. It's a high shrinkage resin as well just from the coefficient of expansion effect - solidify at a high temp, cool down to room temp. Really high shrink resins can even pull away from the face of the mold as they cure and the castings either have a dappled appearance (some areas still in contact with the mold at final cure and some not), or be really glossy (entire face of the casting loses contact with the mold so the casting has none of the mold's surface texture). We may be seeing some of that here. In any event, if Greg wants to reintroduce any of these castings the place to start is with the original masters, not these dimensionally variable castings.

Tom Madden

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