Largest Engine Made By a Model Engineer?

[Mike ColverParticipant @mikecolver51936]

What is the largest engine that a model engineer could build in a well equipped shop?

[Mike ColverParticipant @mikecolver51936]

[JasonBModerator @jasonb]

There are a few 8" traction engines being made, that is 2/3rd scale though of smaller prototypes. Quite a few 1/2 scale showman's engines about which come up rather large too.

[Speedy Builder5Participant @speedybuilder5]

How deep is your pocket ?

[not done it yetParticipant @notdoneityet]

Has to (or should) be of a scale smaller than 1:1? At 1:1 it would become a replica? One guy built a “model’’ Spitfire of slightly less than full scale.

Look up ‘Clive du Cros,’ along with ‘spitfire’ and you may find the details, if interested. I have his book, somewhere.

[Michael GilliganParticipant @michaelgilligan61133]

Wherever would mankind be if ‘models’ could only be less than life-size ?

… modelling is sometimes about education and understanding.

DNA being an obvious case : **LINK**

https://www.nature.com/scitable/topicpage/discovery-of-dna-structure-and-function-watson-397/

… and surely DNA is the ‘engine’ of life.

.

Just a thought … [please excuse the digression]

MichaelG.

.

[duncan webster 1Participant @duncanwebster1]

Chap I know is making a full size kerr Stuart Wren, but he has a lot of big machines having run a small engineering company before he retired. Is this still model engineering? Well he's also building a 7.25" sweet pea.

[OldironParticipant @oldiron]

Posted by duncan webster on 11/12/2022 09:44:17:

Chap I know is making a full size kerr Stuart Wren, but he has a lot of big machines having run a small engineering company before he retired. Is this still model engineering? Well he's also building a 7.25" sweet pea.

Full size is a replica I believe not a model. Must have been one heck of a project.

regards

[Les RileyParticipant @lesriley75593]

Posted by Mike Colver on 11/12/2022 02:26:06:

What is the largest engine that a model engineer could build in a well equipped shop?

A lot depends on the definition of 'workshop'. Many builders of larger models have access to big machines at work. Whilst lots of parts can be made on home size machines, the bigger bits are done elsewhere.

I have built a 4" traction engine at home and am currently 7 years into a 6" engine, again all at home.

The 6" is a 5NHP Burrell Devonshire road locomotive and will weigh around 1.5 tonnes when finished.

My workshop is purely hobby use, I am not a machinist by profession. Note that both the boilers for the above are bought in items as is usual for larger model traction engine building.

Les

[Jon LawesParticipant @jonlawes51698]

A lot depends on the definition of engine….

I've built car engines in my workshop, so that is 1:1 scale…

[duncan webster 1Participant @duncanwebster1]

Posted by Oldiron on 11/12/2022 10:04:11:

Posted by duncan webster on 11/12/2022 09:44:17:

Chap I know is making a full size kerr Stuart Wren, but he has a lot of big machines having run a small engineering company before he retired. Is this still model engineering? Well he's also building a 7.25" sweet pea.

Full size is a replica I believe not a model. Must have been one heck of a project.

regards

OP asked for largest engine, not largest model.

[JasonBModerator @jasonb]

There are a lot of people that would call a Loco the "engine" and the guy controlling it an "engine driver"

Some of my model engines are bigger than the original so do they count if a model is said to be less than 1:1?

Edited By JasonB on 11/12/2022 10:43:34

[Martin Johnson 1Participant @martinjohnson1]

I have almost finished a 7" scale Fowler lorry. Tools used – 11"Kerry lathe., Tom Senior M1 mill, welder, bandsaws etc

Boiler was purchased, but designed by me, as was everything else. All patterns also made by me.

Photo:

Full details of build here:

https://www.flickr.com/photos/140734312@N06/albums/with/72157669955074511

The whole thing was an exercise in answering the OP's question.

Martin

[HopperParticipant @hopper]

Anything can be made anywhere, given enough ingenuity, time and money. There are guys making 1:1 fully functioning replicas/models of famous vintage racing motorbikes and selling them for $100,000. I guess its no more work than making a working model in 1:12 etc. Maybe even easier because big stuff is easier to see and to manipulate than tiny model parts.

It would be handy to have some bigger machine tools than a more usual model makers lathe and mill for this kind of work, but nothing more exotic than a standard 12"/300mm swing Chinese lathe and a Bridgeport clone or even Myford mill clone would do the job. Plus your backyard foundry for engine castings and welding gear for frame making etc. No more exotic than many serious model engineers get.

Burt Munro made the original "World's Fastest Indian" in his back shed with nothing more than a Myford ML7 lathe and a welder. He did cut a bit out of the Myford bed with a hacksaw to accommodate the long-stroke flywheels he made for it. But all the rest, including his homemade cylinders and heads fitted in the Myford before that.

 

 

Edited By Hopper on 11/12/2022 13:14:20

[egaParticipant @ega]

Posted by Hopper on 11/12/2022 13:11:45:…

Burt Munro made the original "World's Fastest Indian" in his back shed with nothing more than a Myford ML7 lathe and a welder. He did cut a bit out of the Myford bed with a hacksaw to accommodate the long-stroke flywheels he made for it. But all the rest, including his homemade cylinders and heads fitted in the Myford before that.

…

The book of the same name is a good read.

I seem to remember that he also slept and cooked in that shed.

[Harry WilkesParticipant @harrywilkes58467]

Posted by Speedy Builder5 on 11/12/2022 07:15:33:

How deep is your pocket ?

The OP didn't ask about cost !

H

[Tony TParticipant @tonyt64954]

I built my 8” tractor in home workshop but had to use my mates large lathe for the flywheel and final drive gear. I went for this engine as it was the biggest thing I could build that still fits under a standard height garage door.

 

 

Edited By Tony T on 11/12/2022 14:32:03

[Ches Green UKParticipant @chesgreenuk]

Tony,

I built my 8” tractor in home workshop

Your tractor looks amazing, and much fun. I'm still at the 'building Stuart models' stage but maybe one day

————

Although Wikipedia 'states' ….

Model engineering is the pursuit of constructing proportionally-scaled miniature working representations of full-sized machines

…I've always seen it as another branch of engineering, one that tries to physically represent a known (or envisioned) machine but on a one-off basis, usually for fun, enjoyment and personal learning.

I worked in Avionics for a while – we had a 'model shop' where aircraft black-box designs were made out of wood at a 1:1 scale so that a test fit of the proposed design could be carried out on the actual aircraft. This modelling wasn't for hobby reasons, but actual commercial gain. It was just before 3D CAD modelling became an alternative.

So I guess there are two slightly different meanings for 'model engineering' a) in the hobby world and b) in the commercial world.

Ches

[duncan webster 1Participant @duncanwebster1]

The OP asked what is the biggest engine made by a model engineer, so whether full size is a replica doesn't enter into the equation. If he has asked what is biggest model made in a home workshop that would be a different issue. Wikipedia's "proportionately scaled" doesn't change the matter, full size is proportionately scaled 1:1,even twice full size would fit this. definition

[Michael GilliganParticipant @michaelgilligan61133]

Posted by duncan webster on 11/12/2022 19:00:10:

The OP asked what is the biggest engine made by a model engineer, so whether full size is a replica doesn't enter into the equation. If he has asked what is biggest model made in a home workshop that would be a different issue. Wikipedia's "proportionately scaled" doesn't change the matter, full size is proportionately scaled 1:1,even twice full size would fit this. definition

.

Tut tut, Duncan … selective quotation !!

proportionally-scaled miniature is what was writ

That said … I am [as you will see from my earlier post] with you in principle.

and anyway … by its very nature, Wikipedia is not definitive.

MichaelG.

[duncan webster 1Participant @duncanwebster1]

Touché

[HopperParticipant @hopper]

Posted by ega on 11/12/2022 13:32:53:

Posted by Hopper on 11/12/2022 13:11:45:…

Burt Munro made the original "World's Fastest Indian" in his back shed with nothing more than a Myford ML7 lathe and a welder. He did cut a bit out of the Myford bed with a hacksaw to accommodate the long-stroke flywheels he made for it. But all the rest, including his homemade cylinders and heads fitted in the Myford before that.

…

 

The book of the same name is a good read.

I seem to remember that he also slept and cooked in that shed.

Yes I have read all the Burt books, there are two or three of them I think. Seems at one stage he moved out of his house into the shed behind so he could rent his house out to get the money to get to Bonneville.

I knew an older lady years ago who had been a photographer at Burt's local newspaper in her younger day and took his photo every year when he was off for his latest bid at Bonneville. She told me he slept in a bed in the workshop with a tarp over it to keep the rain from the leaky roof off it. And reckoned he lived off a pot of stew constantly bubbling away on a burner in the corner that he just added a bit to every now and again. She swears it was the same stew bubbling away every year! If you look in that pic I posted, it looks suspiciously like his toaster on the shelf behind the ML7. Can't eat stew without toast! She reckoned he was a crusty old so-and-so and he kind of looks it in that pic.

With any luck I will be at Bonneville again next year for the motorcycle speed trials week. The bar where Burt, Rollie Free and Marty Dickerson and all those guys drank is still there. And it is still a great week out on the salt. Last time, pre covid in 2019 our team (The Fez Monkeys MC) set an AMA world record in the 350cc Stock Classic class of 98.6mph on a 1970s Kawasaki triple my mate bought out of an old guy's chicken coop for $200 and got running after straightening the forks out. We might even squeeze the ton out of it next year. Not quite the world's fastest Indian but a heck of a lot of fun. And the tailgate party in the motel parking lot every evening is not the least of it. The guys on the genuine Manxes and BMW Rennsports and 300mph streamliners etc are in there with all the chicken-coop special riders!

And getting back on track, most of those streamliners and other special lay-down salt bikes and the restored classics are all done in guys back sheds or home garages, just as Burt did.

 

Edited By Hopper on 12/12/2022 08:31:02

[John OlsenParticipant @johnolsen79199]

So back onto large models, I wonder if the Newcomen engine built by a group of us in Auckland NZ would qualify? It is semi-scale rather than true scale, there being no actual working drawings of any of the originals to allow any claims of rivet counting accuracy. It is not as large as full size while still being large enough to need a truck to move it. In addition, many of the guys who built it are model engineers.

John

[Chuck TaperParticipant @chucktaper]

Naive question.

If building a "x-inch" model that means the scale of the model is x inch = 1 foot. Is that correct?
Whereas a x inch gauge refers to the spacing between rails. Is that correct?

Is there a (simple) relationship between these two selectors or are they incompatible.

I have (briefly) poked around on the web – 'nuff said.
Could someone here could point me towards a decent reference (preferably the old fashioned kind – a book)

When deciding which scale to use what factors might go into that decision. It looks to me that the gauge scale will mandate the (finished) size of any rail based model whereas the x inch per foot allows more leeway with non rail related models.

There is a table in Tubal Cains Model Engineers Handbook concerning track and wheel standards but not enough.

Thanks in advance.

Frank C.

[martin haysomParticipant @martinhaysom48469]

Posted by John Olsen on 13/12/2022 19:54:16:

So back onto large models, I wonder if the Newcomen engine built by a group of us in Auckland NZ would qualify? It is semi-scale rather than true scale, there being no actual working drawings of any of the originals to allow any claims of rivet counting accuracy. It is not as large as full size while still being large enough to need a truck to move it. In addition, many of the guys who built it are model engineers.

don't know if its the biggest but it must be a contender as it is an engine

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