Another Stuart Triple

[kvom]

Some photos to make Jo either envious or nauseous.







Bought from a friend who purchased this in England quite a while back.  He said he'd never get around to it, so I got it at a good discount from the current posted price on the Stuart site.  Doubtful I'd cut any metal until next year at the earliest, but I do intend to model it in Solidworks first.

There's no crankshaft casting, but the plans and parts list show cranks weights; therefore it seems to be a put together crankshaft.

[Jo]

 

Jo

[rhankey]

There's no crankshaft casting, but the plans and parts list show cranks weights; therefore it seems to be a put together crankshaft.

The crank counter weights attach to the webs after the fact, whether you choose to build the crank from a single piece or assembled from many pieces.  The original crank that came with that kit would have been a single piece.

[Mjolnir]

A lot of the Stuart engines used to come with malleable iron crankshafts. in some cases, like with the double ten, the two throw crankshaft was made by welding two of the single throw cranks end to end, possibly by friction welding since it was quite a tidy weld. That didn't stop the one I had being harder than carbide tooling, so in the finish I made one from solid. I think that in later years they did not have access to the malleable iron process, I have seen at least one where the blank was supplied partly machined from solid.

My triple did not come with a crankshaft, not too surprising since all it came with was the baseplate. So I made the crankshaft from solid. That was a bit of an epic but it worked out fine. Most of the material was milled away with the job between centres on the milling table. That is quite a useful technique for crankshafts.

Once the shaft is made, you can mill away part of each disc to leave the counterweights.

John

[kvom]

I've been modeling a good number of the parts from the drawings, as well as reading through Jo's orphans thread.  I've made a few assemblies to get a feel for the arrangements, but still need to model the cylinders.

I'm still on the fence about whether to try to build it.  Other than a few of the larger castings, most of the parts would be easier for me using bar stock.