Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[kno3]

Hello! I have come across a new (to me) manufacturer of steam turbines and engines. The Website is:
http://jc-steam.com
Has anyone bought their products, are they any good?
Who makes them and where? I wasn't able to find any information about the seller on their website and that made me a bit apprehensive.

[bogstandard]

This turbine has been advertised recently on ebay.

It looks to be a 'toy' type of turbine, where the exhaust goes to the middle of the turbine wheel and is collected for a central exhaust.

Can you tell me how many normal boilers can give a continuous output of 65 to 80psi, or even the lower figures of 45 to 60psi ?

Also it doesn't sound too efficient, I think I calculated about a max revs of less than 10K rpm at the high pressure. Something running more efficiently should reach at least 30 to 40k rpm at that pressure, maybe a lot more.

The steam control valve looks to be exactly the same as my last designed turbine one.

The actual size of the engine is massive, not for the sort of steam models we regularly come across. In old english money 3.25" wide, 3.75" high and 6.5" long (approx)

I would suggest you hang back until some other person does a trial or write up on it first.

The ebay site suggests a French connection.

Bogs

[Bunkerbarge]

I think there are a couple of concerns regarding the site as well.  The front page appears to be a standard template that they haven't even bothered to enter either a company name or a tag line at the top.  Also no where can I find a proper company address with the contact being solely via an anonymous e-mail address.

I would not deal with any site like this unless I had verified the company's credentials thoroughly.  A reputable business will always post details of the company including contact phone numbers and a proper mailing address on thier web site.

[bogstandard]

http://cgi.ebay.co.uk/The-Proteus-Live-Steam-Radio-Control-Model-Turbine_W0QQitemZ290301647771QQcmdZViewItemQQptZUK_Trains_Railway_Models?hash=item290301647771&_trksid=p3286.c0.m14&_trkparms=66%3A2%7C65%3A10%7C39%3A1%7C240%3A1318#ebayphotohosting

[mogogear]

I also found this site just recently...All the caveats apply for sure...but Bogs...I think the output shaft has a geared reduction and the RPM's quoted are for after the fact, so it may indeed spin up pretty high with a 8.7:1 reduction...

It is a heavy thing though  1.2kg ---

[bogstandard]

Mogo,

Straight from the figures quoted in the original post

Output RPM (Approx): 1,200RPM @ 45-60PSI, Reverse less 10%
                                1,700RPM @ 65-80PSI, Reverse less 10%. 
                                Reduction Ratio: 4.8:1.

Multiply the 1,700 RPM by the reduction figure of 4.8 = 8,160 RPM.

Straight from the figures quoted on ebay

Output RPM (Approx): 1,200RPM @ 45-60PSI, Reverse less 10%
                                1,700RPM @ 65-80PSI, Reverse less 10%. 
                                Reduction Ratio: 8.7:1.

Multiply the 1,700 RPM by the reduction figure of 8.7 = 14,790 RPM


Both very inefficient for the pressure of the steam being fed.

How come the difference between the two articles for sale?

Wool over eyes, pigs in pokes and buyer beware rings a bell.

But it looks like someone has fallen for it. Lets just wait for the screams.

For that sort of money, I could turn out inefficient turbines by the bucketfull.

Bogs

[kno3]

Thanks guys, your replies are very helpful. I was also concerned about the lack of information about the seller on their website.
By the way, on Ebay he has a feedback: of only 50% positive...

Could you recommand any other turbines for use in a model ship? Small and efficient, if possible.

[Bunkerbarge]

This has actually been discussed in the past and is one of those areas where real life simply does not equate easily to modelling. 

In reality the steam requirements of a turbine are huge, which is exactly why turbine plants are not very efficient even though the turbine itself is.  All the steam has to be taken to a superheat level then recondensed to be used again which requires rather a lot of energy to do.  This is possible in real life where you have the space of a ships hull to play with but just not possible in a model.  Consequently although you can produce a model turbine and you could produce a large boiler to supply it you would be limited to the amount of feed and gas the model could carry.  Recondensing would be incredibly difficult to achieve so a total loss steam system supplying a turbine would be very difficult to run reliably.

Before every one jumps up and quotes examples of where it has been done in the past, I'm not saying it can't be but I am saying that it would be very difficult to achieve and you would need to be at least a competent model engineer to be in with a chance.

I was talking about this very subject with Bogstandard only recently and he wouldn't dream of taking on such a project and he is one of the most competent engineers you could ever hope to meet.

[mogogear]

Bogs-- as a dumb question from the "non-machinists"..

With turbines in general eating so much steam pressure ...

Is there any real advantage to rerouting exhausted steam from a turbine - back into the turbine chamber ? Down steam a touch from the actual steam feed..? Like a bit of a two stage pump? And aimed of course in line with the buckets or fins of the tubine wheel. Is the exhaust at such a low pressure ( even in great volume) that it would add nothing extra in assist?

Just a random general thought

[flashtwo]

Hi,

The turbines in question are the inefficient DeLavel turbines, which use the inertia of the steam to impinged on a bucket wheel the same as a Francis water turbine and, also, why they have some ability in reverse running by re-directing the steam on the rear of the bucket, hence the reduction in performance.

An efficient steam engine (jet, piston or turbine) must allow the steam to expand to do work and, in doing so, cooling and using up its heat energy.

In a normal industrial steam turbine, the steam first impinges on the impulse blades (DeLavel arrangement), where the inertia energy of the steam is absorbed and, from thereon, the steam goes through the reaction blades, where the steam is allowed to expand, produces thrust (reaction) and give up its heat energy. These turbines are not reversable!

As to the idea of multiple turbine chambers, that is also standard industrial practice, whereby the steam passes through high, intermediate and low pressure turbines, exhausting into a near vacuum created by the steam condenser, sucking the last ounce (gram) of energy from the steam!

The other "old chesnut" of a turbine is the Tesla boundary effect turbine, which, although very simple in construction, run at incredible revs.

For a total loss (technical term not derogatory!) steam generator, please refer to the "Flash boiler" thread.

Ian

[bogstandard]

Mogo,

Ian has described the full sized engines very well, and that is where the problem lies. Doing it on a miniature scale just isn't viable. He also mentioned the Tesla, very fast, but also rather inefficient. They can be purchased, but they are very expensive for the power they produce.
http://www.gyroscope.com/TeslaTurbines/

I work on one of similar design to the DeLavel wheel design(slightly different pocket and exhaust design), but I use another rotor specifically for reversing.

I could do it for a much smaller and efficient model sized one, but the costs and times involved wouldn't justify me doing it. Who is willing to pay the cash (at least a few grand) for me to develop it? I am sure no-one would like to pay maybe £600 to £700 each, for just the engine, as that is how much it would cost to make say ten of them, and absorb the development time into the engine costs. There is a lot of interest in them, but very few people who would actually use them.

I think it is for that reason they have always failed when introduced by the main steam engine manufacturers, not cost efficient enough to develop and produce in such small quantities, so they always stuck with the older more inefficient designs (where this post started). OK for the 'toy' type market, but no use for the more discerning modellers we have nowadays.

It is always down to the little man knocking up the odd one in his workshop, where if doing it for himself, development times and costs don't come into it.

I have been there, and the prototype engine is now in my collection. It isn't perfect, but it showed me the definite way to smaller and better things. When Richard saw and heard it running the other day, I think he was rather impressed, and also very unimpressed at how fast it emptied my large dual piston compressor tank.

To put it into laymans terms, it can be done fairly easily, producing a reasonably efficient, lower consumption steam powered model turbine, that will fit comfortably into a model boat, but not by me at this present time. I just don't have the time or will to do it. Maybe a little further into the future, when I feel like experimenting and taking it one stage beyond.

Bogs

[logoman]

I'll let you know Kno3.

The turbine arrived yesterday, and Mogogear pointed me to this thread.
For the money, it's a lovely model, great 'palm of hand' scale, really nicely put together, well thought, well painted and not too heavy. Maintenence..well see

I wouldn't ever consider myself as discerning modeller, but I like to think I've some taste in my small collection of marine steam - mainly Hemmens, Cheddar, Saito, Aster...All these people have managed to turn a talent and passion into small barely profitmaking businesses delivering a world of pleasure to people like me. For those reasons I thoroughly applaude Jim Chalmers and what he's doing.

I'll buy the ladder and manifold accessories, I'm not adventurous enough to try and install it in a boat, but it's certainly a keeper.

If my bigger boilers fail I'll have a great reason to buy the new Maccsteam 6".

Did any see that WADA turbine (without boiler) sell for nearly $700 on ebayUS some months ago? I hope Jim manages to get the turbine into the American market.

[bogstandard]

Logoman,

I'm not adventurous enough to try and install it in a boat, but it's certainly a keeper.

If my bigger boilers fail I'll have a great reason to buy the new Maccsteam 6".

It seems like you are an engine collector rather than a model boat person.

But now that you have one in your hands, would you consider it to be a viable proposition to fit into a medium sized, say 42" to 48" slim type steam hull, without completely filling the insides with boiler and engine?.

Maybe a shot of the engine sitting in (or on) the palm of your hand would give us a rough idea of the size of the engine. It is alway difficult to visualise when they just give dimensions with nothing in the shot to discern physical size.

There is a massive difference between the Jensen/Mamod/Wilesco type of 'toy' engines (as you usually like to call them), with pressed tinplate stands and bits of stuck on chequer plate, and in your words 'I'll buy the ladder and manifold accessories', and the 'miniature' steam plants that are required for efficient model boat running.

Is it a 'toy' or 'miniature' steam engine?
Is it made up and assembled from tinplate pressings or is it machined to nice tolerances.?

Maybe a bit of technical feedback would be greatly appreciated

it's a lovely model, great 'palm of hand' scale, really nicely put together, well thought, well painted and not too heavy.

is not really a technical description.

The engine just might be what the table top display people require, but maybe totally the wrong thing for installation in a model boat.

Bogs

[kno3]

I'll let you know Kno3.

The turbine arrived yesterday, and Mogogear pointed me to this thread.
For the money, it's a lovely model, great 'palm of hand' scale, really nicely put together, well thought, well painted and not too heavy. Maintenence..well see

I wouldn't ever consider myself as discerning modeller, but I like to think I've some taste in my small collection of marine steam - mainly Hemmens, Cheddar, Saito, Aster...All these people have managed to turn a talent and passion into small barely profitmaking businesses delivering a world of pleasure to people like me. For those reasons I thoroughly applaude Jim Chalmers and what he's doing.

I'll buy the ladder and manifold accessories, I'm not adventurous enough to try and install it in a boat, but it's certainly a keeper.

If my bigger boilers fail I'll have a great reason to buy the new Maccsteam 6".

Did any see that WADA turbine (without boiler) sell for nearly $700 on ebayUS some months ago? I hope Jim manages to get the turbine into the American market.

Thanks. Did you run it yet?
If you disassemble it, could you please take some pictures of the rotor?
How big is the turbine only, without that base plate?