Bolton No.2 Mill Engine

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Although it worked ok I was annoyed by the fact that the slide head was not quite in the middle of it's guides (longways). It was caused because the con-rod was just a bit too short. I think this might have been due to this being a Version 1 set of castings and I am using a Version 2 set of plans.

Anyway, not a difficult thing to fix. I plugged the hole and silver soldered it in place.
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Then cleaned up in the mill
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And finally re-drilling and a bit of a cleanup. - The perfect crime!
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Don't you just love silver solder? :-D
 
Another quick update for my little engine. Things are back together now after fixing various issues with the conrod and tidying up some bolts etc. It's looking nice and running well. One of the last jobs was to put some lagging on the cylinder. I am really happy with the results but I still might put some bolts in to hold the lagging. I have some 12ba bolts ordered so I guess I will see how that goes when they arrive!
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---> Video of it Running <---
 
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I thought a guard rail would look good so I built one.
I turned the posts from 1/4" stainless using a half-round form tool. Because they were so spindly I worked from the end towards the base turning it down to size about 1/4" at a time. This worked out well and I managed to make 6 posts. I had to make a little pipe bender to get the curves.

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I think I'm pretty much finished with this engine now. It might be time to start a new project.

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Wawwhhh a surface grinder, thumps Up!
Can you grind the radius and the free angle at once?
 
Thank you for this great documentation .
There I could find a lot of ideas for my own project . 👍
 
The time has come to paint the engine. I thought about this quite a lot and decided to try Japanning. Japanning is what used to be used on old tools such as hand planes. It is a very hard very black paint made from something called Asphaltum which is a dark brown powder.

To make asphaltum paint you mix it with 1/3 turpentine and 1/3 boiled linseed oil. Then after giving it some time to disolve and mix together it is painted on with a normal paintbrush.
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Once everything is painted it is then baked in a convenient oven. I have an old toaster oven which I found in a skip which I use for this kind of thing. It's important to do it outside as it SMELLS pretty much like a road resurfacing machine.

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It's important to bake it slowly. I started at about 120C and gradually ramped it up a few hours at a time to about 240C or so.
Initial results were pretty awful but after another coat and more baking it turned out quite nice I think. The finish is very much like a baked enamel. Very hard and durable and very very black!

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I thought some pin striping might look nice so I had a go at that using a fine white paint pen from the local stationary shop.
It's not too bad I think.

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Beautiful, I envy your talent.
 
A very nice job! You are, I assume, in Australia, as some years ago I too made a Bolton, but a No.1. Mine is much more utilitarian, using a cylinder made from an oregon pattern, which was simply a solid lump of cast iron, with lots of resulting iron chips! I made mine with hard work in mind and it has been adapted to a 5" gauge railway 'carriage', with steam from a copper vertical boiler. All bearings are ball, including the eccentrics, as are the pump eccentrics. Final drive to the rails is by chain. I haven't looked at it for years and I'm afraid that the tin ants might have had a bit of a go at it. None of it is tiny, so it lives under a sheet metal box, outside on the track. If I get around to cleaning off the rust and spiders and perhaps touch up a bit of paint....perhaps.....it might present for a photo or two. I'm not holding my breath.
 
That is just beautiful! Well done Sir!
Never one to just leave it at that.... The oiler is designed for Steam - which condenses and forces minute amounts of oil into the steam flow to be carried into the engine for lubrication. But this does not work with air. However, when running (at shows, etc.) for any length of time on air, I always invert the oilers on my engines. After an hour or 2 they will have emptied the oil into the engine and done their job as lubricators, ready to be re-filled. I suspect the pressure oscillations in the air intake achieve some microscopic pumping that causes the oil to creep out of the oiler, to be replaced with air? Of course, running for a minute or 2 will be fine with just an initial drop of oil in the intake before fitting the air-line.
I use regular car engine oil (7.5W/30 is my "regular" = 7.5W at 15 deg. C.?) for running on air, but proper 50W "Steam oil" for running on steam. I understand the car engine oil has appropriate anti-corrosion additives, lubricants, viscosity improvers, etc. so it is better than simple "7W Lathe oil" (7W at 80 deg.C.?). But for steam, the Steam oil contains detergents so the condensate mixture from oil vapour and steam forms an emulsion that carries on lubricating. But this must be washed-out after each running, otherwise the trapped water will de-emulsify and cause bi-metallic corrosion on the brassy alloys, and rust on any iron.
Enjoy running at your local show!
K2
 

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