Lamp Post Engine

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Simon Collier on 06/07/2020 22:47:07:

[…]
 

Being a model it would surely have to be published in Model Engineer. I wonder why Jim C suggested MEW, perhaps because he subscribes to it?

.

Maybe he wants to use one that size as a work-light on his lathe or mill

… then ‘surely’ it would need to be in MEW 

MichaelG.

Edited By Michael Gilligan on 06/07/2020 22:58:35

[Jim CParticipant @jimc]

Guilty as charged Simon, I do indeed subscribe to MEW. Interesting use as a work light. An improvement perhaps on the current candle power !! I am unsure of the demarcation between the two magazines ? The Lamp Post engine would certainly have some interesting machine setups and manufacturing problems to solve which I though would lean to MEW. Besides that, it would make for an interesting article in said magazine. Just my thoughts.

[Nigel (egi)Participant @nigelegi]

So, what is the process for 1. a request for an article in ME or MEW? 2. for writing the article?

Cheers, Nigel

[David George 1Participant @davidgeorge1]

Nigel can you give me a little more information on the motor. DC? Brushed or brushless? Approx size as I don't want to spend a long time waiting for a delivery and getting the wrong one as the only two small motors I have barely give out 0.5 volts.

David

[Nigel (egi)Participant @nigelegi]

Posted by David George 1 on 07/07/2020 19:49:06:

Nigel can you give me a little more information on the motor. DC? Brushed or brushless? Approx size as I don't want to spend a long time waiting for a delivery and getting the wrong one as the only two small motors I have barely give out 0.5 volts.

David

Hi David, the motor I used is 24mm in diameter and 12mm deep. I found a similar one in a Christmas card that blows snow around a bubble of plastic: The gearing from the flywheel is around 8:1. Hope this helps, Nigel

[Jim CParticipant @jimc]

Hi Nigel. Not sure how you go about producing an article. You need one of the moderators to come along and inform you. As an alternative, you could post some drawings in your photos page and we could get started on it as I am sure a few on here would give it a go. Cheers.

[JourneymanParticipant @journeyman]

Info on preparation of articles for publication is *** HERE *** this is for MEW but presumably similar for ME.

John

[John OlsenParticipant @johnolsen79199]

There is a pack that Neil Wyatt could email to you with all the information you need, including forms to provide the detail they need to pay you. Yes, they do pay for articles, you would probably not want to live only on the proceeds of writing for ME or MEW, but it does make a nice little incentive.

You could write this up in several different ways, for example a short article with a few photos of the finished article, or a longer series with drawings. For the latter you would want some photos of the various machining setups, which can be awkward if you didn't take them at the time.

Sometimes people are a bit shy about writing, which is a pity as I think we miss out on some interesting stuff because of this. You don't have to be Shakespeare to write for these magazines, so don't be afraid to give it a go. It is a nice model.

regards

John

[Sam StonesParticipant @samstones42903]

Nigel,

I sent you a couple of MPs

Sam

[Martin King 2Participant @martinking2]

Posted by Sam Stones on 10/07/2020 03:16:14:

Nigel,

I sent you a couple of MPs

Sam

Good for you Sam, far too many at Westminster…… I'll get me coat

Cheers, Martin

[Nigel (egi)Participant @nigelegi]

Hi All, lots of interest in drawings and so I thought I would share with you all a simple plan for the lantern main frame to see if this would meet your standards. I'm not great at CAD and I find it therapeutic to use an old fashioned drawing board, scan it in and then add nice text (my handwriting is like a spiders scrawl).

A lot more to do, but would be grateful for some feedback, thanks, Nigel

PS: uploaded image to here so that you should be able to click and zoom in

Edited By Nigel (egi) on 10/07/2020 21:48:50

Edited By Nigel (egi) on 10/07/2020 21:49:58

Edited By Nigel (egi) on 10/07/2020 22:14:32

[Jim CParticipant @jimc]

Hi Nigel.

The development drawing looks ok to me and clearly worked for you. Did you use a sheet metal folder for the fold lines when producing the shape ? Cheers, Jim.

[Speedy Builder5Participant @speedybuilder5]

Nigel, it may have been easier to have used an adjustable set square using an edge of the sheet as your datum line, but full marks for the method you used.

[Nigel (egi)Participant @nigelegi]

Posted by Jim C on 11/07/2020 15:43:50:

Hi Nigel.

The development drawing looks ok to me and clearly worked for you. Did you use a sheet metal folder for the fold lines when producing the shape ? Cheers, Jim.

Hi Jim, I made my own clamp to file and fold to. Image below of the clamp

When folding I had to work outwards from the centre fold. For the folding process I clamped the one side and used a wide piece of steel that I could force the edge over with.

[John MCParticipant @johnmc39344]

I've shown this thread to my partner, the reaction was "thats pretty, it would make a lovely Christmas table decoration"!

As we all know, when ones partner makes a comment like that its a request to make one. A look in the box of things that might be useful has found a small slide valve cylinder, a possibly usable flywheel and a small motor that may be suitable as a generator.

I'm looking forward to building my take on the "lamp post engine", a make it up as I go along project. Anyone else having a go?

John

[Nigel (egi)Participant @nigelegi]

Posted by John MC on 13/07/2020 12:24:52:

I've shown this thread to my partner, the reaction was "thats pretty, it would make a lovely Christmas table decoration"!

As we all know, when ones partner makes a comment like that its a request to make one. A look in the box of things that might be useful has found a small slide valve cylinder, a possibly usable flywheel and a small motor that may be suitable as a generator.

I'm looking forward to building my take on the "lamp post engine", a make it up as I go along project. Anyone else having a go?

John

Hi John, fantastic, my engine was made up as I went along, but based on an engine I saw from Malpress Peake. Do share details as you progress. Best regards, Nigel

[Sam StonesParticipant @samstones42903]

John,

As an alternative (temporary) power supply, especially if you intend it to be a table display you could, instead, drive the steam engine, running the electric motor (and LEDs) from a battery. That way a compressed air supply would be unnecessary.

Okay! Not so cool?

I'll wash my mouth out

Sam

[John MCParticipant @johnmc39344]

Using the electric motor to drive the model is an interesting idea.

What I am going to try is using compressed air from a small pressure vessel, (~2" dia x 4" long) concealed in a base to drive the engine for short periods. My intention is to charge the vessel with a bicycle shock pump so could have up to 300psi available!

John.

[Michael GilliganParticipant @michaelgilligan61133]

and there was I … Fondly imagining a repurposed Sugar Bowl, filled with Coal

”one lump or two, my dear ?“

MichaelG.

[JasonBModerator @jasonb]

John you could also include a small spirit (idea for Xmas) fired boiler then you would have a self contained unit

Edited By JasonB on 14/07/2020 10:10:06

[SillyOldDufferModerator @sillyoldduffer]

Posted by John MC on 14/07/2020 08:01:31:

…

What I am going to try is using compressed air from a small pressure vessel, (~2" dia x 4" long) concealed in a base to drive the engine for short periods. My intention is to charge the vessel with a bicycle shock pump so could have up to 300psi available!

John.

It's easy to estimate from the piston stroke & cylinder size how much air the engine will eat. Never trust my maths, but I reckon a 2" dia x 4" pressure vessel holds about 25 cubic inches of air at normal pressure, or about 500 cubic inches compressed at 300psi (formula from Engineering Toolbox)

So an engine using 0.5 cubic inches of air per stroke would do about 1000 revolutions before running out of air – not long.

The other challenge is the need to reduce the pressure from 300psi to whatever the engine runs best at, probably in the range 3 to 15psi. The regulator on a commercial air compressor does this by bleeding air from the high pressure side through a valve worked by a diaphragm controlled by a spring, which the user can tighten or loosen to adjust the output pressure. I don't recall seeing a home-made design, or a commercial unit that could be hidden in the base of a model engine. I've not looked hard.

I wonder if paint ball accessories might help? Disposable liquid Carbon Dioxide (about 900psi) in 12g, 88g, 12oz and 20oz cylinders. Also, air cylinders in various sizes and pressures up to 4500psi. But I think they have to be filled professionally, and it all looks a bit pricey.

Fair bit of fuss using compressed air to show off engines in the home, a secret electric motor quietly turning the engine is much easier to arrange. (I test my engines with a small Stanley compressor, it has a 1.1kW motor and a 6 litre reservoir. Far too big and noisy, it dominates the scene.)

What's needed for showing off engines is a small quiet compressor producing a lot of air at moderate pressures. Easy to get high-pressure low volume and low pressure high volume compressors, but not quiet mid-pressure, mid volume pumps. Airbrush compressors are often recommended.

Dave

[HopperParticipant @hopper]

Fullsize air compressor in the workshop with pressure reducer/regulator and then 30 foot of 1/4" clear plastic tube run along the skirting boards to the display?

[Nigel (egi)Participant @nigelegi]

Posted by JasonB on 14/07/2020 10:09:48:

John you could also include a small spirit (idea for Xmas) fired boiler then you would have a self contained unit

Edited By JasonB on 14/07/2020 10:10:06

Hi Jason, I quite often see these glass boilers, do you have any specifications and or guidance on their use? Best regards, Nigel

[John MCParticipant @johnmc39344]

I'm wondering about actually running the engine on the dining room table now, oil being flicked about won't enhance the flavour of the meal!

S.O.D., I broadly agree with your numbers. The cylinder I plan to use should consume about a quarter of the air you have used in your sums, assuming my sums are correct. Might need to find a bigger vessel to get a few minutes running. There is a vessel sold for the initial inflation of tubeless bicycle tyres, can't remember what its called, might be worth a try.

I might consider disposable Co2 cylinders if my original ideas are unsuccessful.

Like the idea of some form of boiler, thing is, this is supposed to be a quick project, it could easily develop in to much more!

John

[JasonBModerator @jasonb]

Sorry, no details of the glass boilers, some of the German suppliers do simple kits with them in but a small metal boiler would work, the plastic tube acts as the safety valve popping off if pressure gets too high

The other option is just to supply a length of tube and pass it around the table to see who has the strongest lungs, couple of "steam" engines I have built recently can be run by blowing, even my 10V will do it but not for long as I go blue in the face!

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