View single post by Jon Dierksheide
 Posted: Sun Jan 12th, 2020 05:43 am
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Jon Dierksheide


Joined: Sun May 27th, 2018
Posts: 33
Hi Keith,

Thanks for the posts. Always interesting to read.
The EBT machine shop must be a fascinating place.
That picture of the machine was something I had never seen before.
The machine shop is documented on the internet,
and this photo of it has a name tag of a Horizontal Boring Mill which seems most accurate,
as it appears it could be used for both boring and milling. 

Says it's a horizontal boring machine.
Wikipedia Commons has a shop layout and calls it a slotter (Q in the diagram):

Shop Layout With Slotter

This was the first reference I found and Google failed me. 

There are very few references to what a slotter is,
but it sounds like it is related to a planner or shaper,
and this machine has a rotating shaft (there is a spindle support on the end),
not a back and forth planning motion.
It appears they were used to bore steam cylinders,
and maybe brake cylinders. 

I'm not a steam engine expert,
but it would seem like engine cylinders would not be machined,
after they were put on an engine. 

Do they wear out? 

I don't think in the good old days,
there were ways to build up and re-machine cast iron cylinders,
and I assumed they lasted as long as the engine. 
Or maybe the castings were thick enough you could true them up,
if they wore a little unevenly. 

It just doesn't seem like there would be much need for something just to bore steam cylinders. 
It is the only machine in the shop that looks like it could be used as a horizontal mill,
so maybe there were other uses.

Here are photos of one boring the cylinders of a steam engine in a modern rebuild:

Fig 2 here shows a similar machine,
and at the bottom there is a diagram of one with a steam cylinder:

So it appears it was used to bore steam cylinders.

Here are a couple pictures of similar smaller ones:

A little digression from the Gilpin,
but always fun to see what was done in the back shops of a steam railroad.

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