The Draft and Inside Passage(s)

Taking the path of least resistance (that being the easiest thing to accomplish with a minimal amount of thinking), we began installing the inside steam passages from the valve chamber to the piston cylinder. We concentrated on completing the rear passage as the front cylinder plate forms one side of the front passage and we are not yet ready to permanently install the plate. I cut out the pieces and only burned my fingers a couple times as I sanded down the parts to fit. Here is a picture of the completed passage.

Further examination into what had to be finished to allow the front plate to be permanently installed only succeded in opening up a fresh can of worms. A moderate quantity of brain cells were burned up trying to figure out the exhaust nozzle assembly and how to make the inside area airtight. Of course the first thing that immediately popped into my head was "Why is it so important that the interior of the cylinder block is airtight"? Master Ed quickly explained "the draft" and that the process of expelling the steam and boiler exhaust would create a draft through the boiler and that air leaks had the potential to severly impact the draft efficiency and in turn the burner/boiler performance. OK, OK lets make it airtight!

Further analysis led us to the conclusion that we need to finish the work on the cylinder block and smokebox saddle. After another pondering/plan checking/picture looking session we realized that our plans had been incorrectly drawn. As a result, the front and rear plates that Dave and the plasma cutter had made for the cylinder block were incorrect with relation to the smokebox saddle area. Hey, nothing that a little bandsaw work and welding cant remedy! So, in conjunction with the re-work of the smokebox saddle and after a little brainstorming session (and a quick little peek into Fidel's 2-8-2 smokebox!), Ed came up with the idea to kind of box-in the area around the exhaust nozzle manifold. This "boxing-in" would separate the exhaust mainfold and nozzle from the lower portion of the cylinder block and thus drastically simplify the process of making things airtight. More on this later.....

Building Blocks 3

With the rear heads now completed, our efforts are refocusing on completing the cylinder block. The exhaust lines have been plumbed from the cylinders to a center collector ring where the exhaust nozzle will be bolted to the ring. I kind of like this setup as it allows the nozzle portion of the exhaust assembly to be easily removed to allow us to try different sized nozzles.

Two of the plumbing joints on one side of the cylinder have been left unsoldered to allow us to continue to dissasemble the block into the individual components. But, Ed will soon begin to weld more of the block together and it will eventually become one big permanent piece. I need to start cutting out all of the little pieces that will be used to fabricate the steam passages between the valve cylinder and the piston cylinder.