I am a novice machinist and would very much like to build my first Stuart model Steam engine, but what engine would you suggest i start with? Have built two wobbler steam engines form scratch material, one is a simple single acting engine , and one is a double acting. Another question, because I am from South Africa I do not have ready access to BA taps and dies and imperial drills and reamers. Can I convert some of the holes etc to metric or would i over complicate the work?
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definately get yourself Ba taps dies and drills.
As far as best first engine, the S50 probably requires least machining and is easy to machine.
However when it comes to setting up for machining I find something a bit bigger is easier to get your hands on.
You could do a lot worse than a Victoria. If you are unsure of some of the complicated stuff, Stuart will provide any of the bits pre-machined like the connecting rod, flywheel or the cylinder. Just get in touch and get a quote. (They do charge but it’s not too bad).
Some advice, when machining bits that fit together, machine them together. (E.g. superglue valve chest and cover to cylinder for drilling holes in one go. Tapping size then remove chest and cover and drill out to clearance size. Bit of heat from blowtorch breaks superglue.
Be aware all machining has inaccuracies. If you machine every part independently sometimes it won’t fit together. This is due to errors either cancelling each other out or adding up. So machine major parts to spec but some parts that line things up, machine to fit. I have restored 4 Victoria’s and not one had the crosshead running in the guides correctly. So I have to line up the cylinder parallel to the top of the soleplate and running down the centreline, then machine the spacers that set the guides to a matching height.
anyway good luck and let us know how it goes. Why don’t you start a YouTube channel.
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The 10V is also a model that can be successfully made using only a lathe. But it requires a lot of jigging and mucking about to do so. You need to be familiar with four jaw chucks really.
Probably the easiest Stuart to build from castings is the S50. If you carefully watch Keith's series on the Victoria you are looking at very similar work and techniques, size being the only difference. Keith, being a practical engineer, shows you the best/easiest/most practical way to do things with the minimum of machinery and tooling. Nothing theoretical with Keith, he just gets on and does the job.
BA and ME taps and dies need not be that expensive and you should look at them as an investment. I use carbon steel taps and dies, and have made many, perhaps hundreds of, threads and only broken two taps (so far!). Used with care they will last for years. I have found the best source for these is Tracy Tools (usual disclaimers, just a happy customer), you'll find everything you will need and more!
Whatever you choose to build, good luck
Hi Tim, thank you very much for your reply end your advice. Unfortunately we don't have a supplier of the Stuart Model Castings here in South Africa, I contacted Stuart directly in the UK, and they assured me that they will be able to supply all the tools I need. I am also scared for botching up some of the parts, especially because I don't have all the tools that would make the build easier. I followed Mr Pete's (Tubalcain) build of the Stuart Progress on his You Tube Channel, as well as almost all of Keith's videos. Darn, they make it look so easy. I am building a lot of tools, as well as engines form scratch, I am busy with my second wobbler, trying to hone my skills. Thank you very much for the advice on the Victoria, I started watching Keiths Video's yesterday on that build. All of the best with you project, please let me know of you progress.
Hi Anton, I'm a novice machinist from the US and I can give some advice based on my experience.
Do you have a local Stuart Models dealer in South Africa? The UK is the epicenter of model engineering. Keep in mind that even if you doing have a local dealer, if you need parts (i.e. if you screw up machining a casting), you'll be ordering replacements from the UK. I'm on my 3rd Stuart 10V cylinder casting.
Instead of converting hardware to metric, I'd recommend buying proper BA tooling from the UK. Because you're building miniature stuff, the proportions on things like nut/bolt head size to thread size won't look as good if you switch over to imperial/metric hardware sizes. BA hardware (whether intention or accidental) is fairly true proportionally to the hardware used on bigger engines and just "looks right". Also, if you end up wanting to buy pre-made fixtures (like valves and drain cocks) from suppliers, those will come in ME thread sizes. Trying to start out metric will cause you more pain than its worth.
BA/ME taps/dies you can over the web from UK model engineering suppliers. Imperial drills and reamers should be easy to buy over the Internet. When buying tooling, I look on Amazon/eBay first, and then go to the UK model engineering suppliers on the web if I can't find it there.
Back to the original question: I would recommend not making the mistake that I did, which was starting with a small engine like a Model 10 (I picked the 10V) as your first model. I'm a big guy with big hands. The parts are really small for my big hands and tapping super small 7BA holes in cast iron is turning out to be the bane of my existence without any previous experience. The 2nd kit I've bought is the No. 9, which is much larger. I'm trying to force myself to not open it until I finish the 10V but that's becoming problematic and I'm ready to give up on the 10V and open the 9. I've probably spent more on replacement 10V castings/parts than I did on the original 10V kit because I keep botching some of the "small stuff".
Were I to start from scratch right now, I'd probably get a Stuart Victoria and follow along with Keith's current video series "Building the Stuart Victoria". The Victoria seems to be fairly large and the right size to get started on. If I didn't elect to go the Victoria route, a No. 9 or No. 1 would be the next ones I'd look at.