Stuart Beam Engine

Just received a new Beam Engine kit from Stuart.

I've just noticed a recently finished one for sale on EBay and the 4 main bearing blocks appear to be made from single blocks of material yet in my casting kit they are separate split bearing castings requiring to be bolted together before final machining. Why the difference?

Not sure about your exact model but Stuart have had many changes to many of their models over the years. Like every product, changes happen over time. It is certainly more prototype-like to have split bearing blocks and caps - a real beam engine in full size from mid to late 19th century certainly would, likely secured by studs and nuts, not bolts.

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My kit main drawing indicates studs and nuts. Strangely, there's an amendment sheet in the kit showing split bearings with studs dated 29/01/2015 but the same split bearing drawing is on the main drawing (July 1993) with no difference.

Edited By Martyn Edwards 1 on 25/01/2021 18:18:07

Looks like the builder of the one on e-bay took the easy route and did not bother to split the one piece castings (extrusions) that they now supply.

He has done similar on the Watt linkage by leaving them all flat rather than turning with a nice fish belly shape

Strictly speaking the bearing caps should have nuts and lock nuts on the studs so you don't close up the split bearings too tight.

Edited By JasonB on 25/01/2021 18:42:32

Martyn

My Stuart Beam has split main beam bearings and it is at least 30-40 years old. I got it part built 25+ years ago. The drawings (parts, #90048 and GA, #90047) that came with it show split bearings held together with hex cap screws. I have changed them to studs and nuts to be more prototypical as Jeff says. Perhaps the solid ones in the picture are replacements for ones that got lost, or didn't bother splitting them ( or for non rectifiable mistakes during machining?).

John

edit: Jason beat me to it!

Edited By John Purdy on 25/01/2021 18:26:47