Interactive article on Beam Engines

[glinscottParticipant @glinscott]

Hi,

Long time Model Engineer subscriber, first time poster :).  Hopefully this is the right forum for this post.

Recently, I was reading through Richard L Hills “Power from Steam”, and “Power in the Industrial Revolution”.  The books are wonderful, but it’s sometimes difficult to build an intuition for the concepts from static pictures.  That led me to do a deep dive into the beam engine: how it works, the history behind it, and the engineering tradeoffs the builders faced.  The article has quite a few interactive figures that I hope make the concepts easier to see.

Article: https://glinscott.github.io/beam-engine/

The engine is based on this great CAD model: https://grabcad.com/library/horizontal-beam-engine-1, which is in turn based on https://www.ajreeves.com/model-engineer-beam-engine-me-beam.html.  I rigged it on OnShape, and wrote a custom exporter so the article could show the different mechanisms clearly.

I would be very grateful for any corrections or feedback.

Thanks,
Gary

[Michael GilliganParticipant @michaelgilligan61133]

That looks beautifully done, Gary

… I shall return to it this evening.

MichaelG.

[Michael Gilligan]

On Michael Gilligan Said:

That looks beautifully done, Gary

… I shall return to it this evening.

MichaelG.

Thanks!  Enjoy the Saturday :).

[glinscott]

On 18 July 2026 at 02:47 glinscott Said:

[…]

I would be very grateful for any corrections or feedback.

Thanks,
Gary

In the grand scheme of things, Gary … this seems very trivial, but you did invite comment:

It would seem more logical, to me, if you started the story with Newcomen’s atmospheric engine, instead of starting with a high-pressure Boiler

I must leave it to the forum’s steam experts to peer-review the technicalities … but for myself, the article is a joy !

MichaelG.

[PeteParticipant @pete41194]

The amount I don’t know about steam would easily fill a massive library Gary. But from my perspective, I think it’s very well done and must have taken quite a bit of time. 👍

[Michael Gilligan]

On Michael Gilligan Said:

On 18 July 2026 at 02:47 glinscott Said:

[…]

I would be very grateful for any corrections or feedback.

Thanks,
Gary

In the grand scheme of things, Gary … this seems very trivial, but you did invite comment:

It would seem more logical, to me, if you started the story with Newcomen’s atmospheric engine, instead of starting with a high-pressure Boiler

I must leave it to the forum’s steam experts to peer-review the technicalities … but for myself, the article is a joy !

MichaelG.

Feedback is always great :).  Do you mean the first steam vessel, where the water is boiling?  It’s meant to illustrate the relationship between heat and steam – but I see what you mean, it does look like a high pressure vessel.

I’ll have to think on that – the Newcomen engine needs the concept of a steam-created vacuum to be explained.

[Pete]

On Pete Said:

The amount I don’t know about steam would easily fill a massive library Gary. But from my perspective, I think it’s very well done and must have taken quite a bit of time. 👍

Thank you!  Yes, on and off work for a year or so :).

[renardiere7Participant @renardiere7]

I think this is a wonderful piece of work, I’m in awe of your computer skills and I’m a fairly competent Onshape user having used it from when it first became available. Well done!

[glinscott]

On glinscott Said:

[…] Do you mean the first steam vessel, where the water is boiling?  It’s meant to illustrate the relationship between heat and steam – but I see what you mean […]

I think the problem is more to do with the conceptual flow of your text

The illustration is fine if it just shows water boiling to steam …

The genius of Newcomen’s design was that he used the shrinkage of the low-pressure steam when cooled.

MichaelG.

[Ches Green UKParticipant @chesgreenuk]

Gary,

Great article on the Beam Engine, thank you.

You did ask for ‘corrections or feedback’...hmm, not much that I can find.

But I’ll have a go…maybe grey text on a white background makes it a little bit more difficult to read, some of the graphics’ labelling could be one or two font sizes larger….but these are pretty insignificant things.

I liked the ‘Measuring the work’ interactive graphic….and how Watt and colleagues kept adding fresh developments over time to help make the profit margins larger and larger.

Yup, all very good stuff.

Ches

 

[Michael Gilligan]

On Michael Gilligan Said:

On glinscott Said:

[…] Do you mean the first steam vessel, where the water is boiling?  It’s meant to illustrate the relationship between heat and steam – but I see what you mean […]

I think the problem is more to do with the conceptual flow of your text

The illustration is fine if it just shows water boiling to steam …

The genius of Newcomen’s design was that he used the shrinkage of the low-pressure steam when cooled.

MichaelG.

Yes, agreed – I was trying to show the potential power of steam, but you are right, it’s not available to Newcomen.  I mention they can’t use high pressure steam in the piston section, but that’s not really well defined in the early parts of the article.  Will keep thinking on it, thanks!

[Ches Green UK]

On Ches Green UK Said:

Gary,

Great article on the Beam Engine, thank you.

You did ask for ‘corrections or feedback’...hmm, not much that I can find.

But I’ll have a go…maybe grey text on a white background makes it a little bit more difficult to read, some of the graphics’ labelling could be one or two font sizes larger….but these are pretty insignificant things.

I liked the ‘Measuring the work’ interactive graphic….and how Watt and colleagues kept adding fresh developments over time to help make the profit margins larger and larger.

Yup, all very good stuff.

Ches

 

Thanks!  I’m curious, were you reading on a laptop, or your phone?  The font sizes can be a bit small to fit in the figures, agreed.

[renardiere7]

On renardiere7 Said:

I think this is a wonderful piece of work, I’m in awe of your computer skills and I’m a fairly competent Onshape user having used it from when it first became available. Well done!

Thanks!  Many hours in OnShape, it’s a great tool :).

[Ches Green UKParticipant @chesgreenuk]

Gary,

Thanks! I’m curious, were you reading on a laptop, or your phone? The font sizes can be a bit small to fit in the figures, agreed.

I forgot to mention I was reading the article today on a 24″ 1920 x 1200 display on a W10 PC, at a distance of about 1 metre.  Last night it was on a 15″ Macbook Air, at a distance of about 0.5m.

Ches

[Michael GilliganParticipant @michaelgilligan61133]

Please forgive the intrusion, Gary

I just stumbled across this:

Newcomen engine collected by Henry Ford

.

.

MichaelG.

[Howard LewisParticipant @howardlewis46836]

Steam “power” began with the Savery and Newcomen engines, but James Watt greatly improved efficiency (and economy) by moving the condensation part of the cycle out of the cylinder.

They did not use the steam to produce power, just atmospheric pressure. The return stroke was gravity powered by the weight of the pump rods extending down the mine.

Watt then devised his linkage, which replaced the chain, to connect the arctuate motion of the end of the beam to the linear motion of the piston rod.

In some respects, Watt stifled the use of steam engines, by strictly enforcing his patents on the condenser, motion, and the crank. Hence the Cornish steam cycle! (There were few rotative engines in Cornwall, using beam engines to carry men and materials to and from the surface).

Even then Watt used low pressure steam, (5 psi) which meant the engines were big, and low powered, because the weight limited speed.

Richard Trevithick, who pioneered steam powered vehicles, was a believer in what he called “strong steam”, at aboiut 40 psi so that a smaller engine, running faster, could deliver as much power as the bigger low pressure engines.

The later development of compound and then triple or quadruple expeansion engines improved both power output and economy.

(If you want to see the largest triple expension engine in Britain, in action, visit The Water Works Museum in Hereford (UK) on a steaming day . It is entirely run by volunteers, so only open on Tuesdays and Sundays, – which is often a steaming day.)

Howard

[JourneymanParticipant @journeyman]

Kempton Steam Museum may disagree on who has the largest working triple expansion engine.

This one is quite large, about 800tons and 62ft tall. Quite impressive when it is running. They actually have two but only one runs. You can get a walking tour of the out of service one!

Gary’s guide is great for the theory but the real things, whether at Hereford or Kempton are impressive.

John

[Author]

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