# Generator plans?



## Rudy (Mar 20, 2018)

I have been searching for plans to build an old style generator that will go together with my old style engines like the Stuart 10V and soon the Farm Boy.  Preferably without permanent magnets so the drag will be less when just coasting. 
No luck so far.
Anyone seen anything like it ?

Rudy


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## Rustkolector (Mar 21, 2018)

Rudy,
For small dynamo's the PM Research dynamo kit is ideally sized for the Stuart 10 engines. It is permanent magnet design which causes some cogging, but the rotor magnetic attracting and repulsing action known as cogging cancels out. It does not add any drag to the engine without electrical load present. Also, old Stuart model generators are around, but rare and pricey. Another alternative is to view Tubalcain's Youtube video's of building a model dynamo and be creative. [ame]https://www.youtube.com/watch?v=Zk-nJ6QpTAw[/ame]

Otherwise you can find DC motors suitable for generator use and disguise them with a vintage looking housing. It is a trial and error approach, and you will usually end up with a PM motor.

With the Jerry Howell Farm Boy engine, the full-power pulses of a hit & miss design would cause considerable irregular voltage fluctuations when driving a dynamo. Back in the day, very few H&M engines were used for electric lighting for this reason. The addition of a switch mode voltage converter would be required to smooth out the voltage fluctuations.

Larger scale slow speed alternators or rectified dynamo's are somewhat easier to create, however these would be 4" to 6" diameter and larger than scale for your engine choices. They would definitely be PM and have some cogging, but as I said before, no unloaded drag. 
Jeff


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## Rudy (Mar 21, 2018)

Thanks Jeff. I plan to put on a DC/DC converter to give me some "useful" voltage, so the output level is not an issue. The generator kit from Stuart (and PM maybe) looks pretty ok, but has permanent magnets. I imagine a vintage motor with just windings, no magnets, could be a place to start.
Rudy


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## ShopShoe (Mar 21, 2018)

Historical Diversion for those interested, don't read if you don't care.

"Back in the Day," when Hit and Miss engines were being used on farms and other remote locations for many tasks, "Electric Plants" consisted of banks of batteries that could be charged by a small gas engine generator or even a windmill. 32-volt (and other) systems were popular in the central U.S. The irregular power from a small engine and generator would not be consistent enough for reliable use, so the engine charged the batteries, which were used for mostly lighting. I have seen other appliances sold for these systems, but they were not that popular and it is rare to find surviving vacuum cleaners, etc. today. My Father used to remember watching 16mm films at church dinners at his remote rural church powered by such a system and he remembers it flickering, slowing down, speeding up, and generally being hard to watch. That would have been in the early 1930s.

I have occasionally seen the glass cases from those old batteries from time to time and most people do not know what they are.

It would be an interesting project to model  such a system: How would one make miniature plug fuses in miniature ceramic fuse boxes?

Pardon the diversion,

--ShopShoe


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## Rudy (Mar 21, 2018)

ShopShoe, I think your point is very relevant. After all I'm searching for a vintage looking and feeling solution, so a flickering light bulb would be just fine. I think I will go searching for pictures of vintage power plants and try to make a model resembling something made at that time. Maybe ad a homemade accumulator in a glass tank.
Rudy


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## deverett (Mar 21, 2018)

What sort of size accumulator jar would you be looking at, Rudy?  Leclanche cells were (I think) square and if so, something like an HP sauce bottle cut down might be suitable.  If not the right size, at least it will give you some food for thought.

Dave
The Emerald Isle


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## Rudy (Mar 21, 2018)

Dave, yes, I'm thinking like three small square sauce or food oil bottles cut to suitable depth. Will look very Edison like. I will study those Leclanche cells, thanks.
Rudy


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## TonyM (Mar 21, 2018)

How about converting a brushless motor. Or for more authenticity a brushed motor.


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## Rudy (Mar 21, 2018)

Tony, a conversion is absolutely the safest route to a working generator, for sure. I'm after something that looks authentic, so covering up a motor can be difficult. Thinking of maybe using the stator windings from a motor of some kind. The rotor will be visible and probably not all that difficult to make.
I will definitely search for a donor motor that could do the job.
Looking to achieve something like those in the pics.
Rudy


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## Rustkolector (Mar 22, 2018)

Rudy,
The alternators you show above are somewhat later era AC alternators than I thought you were looking to model. I have built this type of model alternator using a ceiling fan motor stator and a PM rotor. I know you don't want to use magnets, but there is no other way to feasibly excite a model alternator without using magnets. Otherwise you must have a wound rotor, working slip rings, a separate power supply, and a voltage sensing regulator to control the excitation current and voltage output at the stator leads. Too complex for a working scale model. The 6" dia. alternator in the photo below is an AC alternator capable of a 300-700 RPM operating range. Mine is rated at 100 watts at 600 RPM driven by a 4 cylinder gas engine. .

The second photo is of a 4" dia. PM alternator made to simulate a DC dynamo. The stator is a rewound 3 phase battery charging alternator stator. It is rated at 36 watts @ 500 RPM and regulated at 12vdc output. It will produce more wattage, but the rating is proper for the engine that drives it. 

The biggest problem I found building direct driven model generators was the difficulty finding small diameter short stack stators with enough poles to get adequate voltage and amperage at a reasonable RPM.    
Jeff


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## Rudy (Mar 22, 2018)

Jeff, actually I was about to ask you about your generator that I saw in your price winning build. Very good-looking machines. Both the plant and the generators. Your approach probably has a much higher chance of success than without permanent magnets. I like both designs. The reason I&#8217;m thinking in the direction of the ones in the pics is just the looks. Beautiful machines I can watch for ever. At this stage I&#8217;m gathering information, inspiration and I&#8217;m learning. 
How/where did you get the housing for your &#8220;dynamo&#8221;?
Rudy


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## ShopShoe (Mar 22, 2018)

For more pictures of really old power plant equipment:

http://www.edisontechcenter.org/Folsom.htm

I find it all interesting to look at.

--ShopShoe


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## ShopShoe (Mar 22, 2018)

More information on a generator/battery system:

After re-reading your earlier response to my post yesterday, I looked this up:

http://www.delcolight.com/20.html

I have seen one of these systems preserved. The one I saw had a bank of fuses on the wall near the batteries.

--ShopShoe


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## Rustkolector (Mar 22, 2018)

Rudy,
Regarding the generator housings, you first start with a stator and winding. That is the most important  part. Once I had selected the stator and winding, the housing was then  fabricated around it. In the case of the dynamo I used slices of heavy  wall aluminum tubing screwed together with some epoxy filler and a few cosmetic additions. In the  case of later era AC alternator, the housing is more simple. I sandwiched the stator between two  pieces of milled flat stock. The rest is cosmetic.  
Jeff


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## Rudy (Mar 23, 2018)

Thanks Jeff. I like your ideas. And the link to DelcoLight from ShopShoe. So sweet. The more I dig into this the more I want to make a model electric plant with all those vintage charming elements.
Talking about vintage elements. the picture is actually taken out of my office window today. The water tube is wooden and is probably more than 100 years old. And in the building at the end, yes, a very old electric plant, stil active. I have seen it 30 years ago, but now I'm going to ask for a tour with a whole new perspective.
The buildings used to be an old paper factory, but now hollowed out and converted to a hyper modern office environment.


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## Manfred04 (Aug 30, 2020)

this generator is a 3D print. It is based on air coils and has no detent torque.

a construction report with castings parts follows


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## SmithDoor (Aug 30, 2020)

Most know Edison did not AC.
But the DC motors and generators need AC to run.

Just look ate the brushes and rotor AC.

Dave

PS: Had Edison seen that Tesla might have lost his pattern we will never know.




Manfred04 said:


> View attachment 118967


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## Manfred04 (Aug 30, 2020)

Dave, this generator runs on DC, the rotor is from a slaughtered Dunker DC engine. The copper windings are dummy and only decoration.In the video of the generator, 300 LEDS light up at slow rotation by hand. My knowledge of electricity is very poor and I am satisfied that it works somehow.


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## SmithDoor (Aug 30, 2020)

It looks great.
I was pointing out a little know face about DC motors and generators and the current war between Edison and Tesla.

Dave



Manfred04 said:


> Dave, this generator runs on DC, the rotor is from a slaughtered Dunker DC engine. The copper windings are dummy and only decoration.In the video of the generator, 300 LEDS light up at slow rotation by hand. My knowledge of electricity is very poor and I am satisfied that it works somehow.


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## Steamchick (Aug 31, 2020)

I had a similar desire for a "mock-up" of a large alternator style generator. So I made mine with Sturmer Archer bicycle components. See my post in this website. I mostly make without plans, as the odd drawing, sketch, or chalk-board sketch is adequate when I am building. (FAG packets have too many health warnings nowadays). I am happy with 10W. - I just have to couple-up an old Stuart Sun engine (made 18 years ago) and boiler (in construction).
I love the high quality models posted and industrial history. Thanks.
Enjoy!


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## Steamchick (Aug 31, 2020)

ShopShoe said:


> Historical Diversion for those interested, don't read if you don't care.
> 
> "Back in the Day," when Hit and Miss engines were being used on farms and other remote locations for many tasks, "Electric Plants" consisted of banks of batteries that could be charged by a small gas engine generator or even a windmill. 32-volt (and other) systems were popular in the central U.S. The irregular power from a small engine and generator would not be consistent enough for reliable use, so the engine charged the batteries, which were used for mostly lighting. I have seen other appliances sold for these systems, but they were not that popular and it is rare to find surviving vacuum cleaners, etc. today. My Father used to remember watching 16mm films at church dinners at his remote rural church powered by such a system and he remembers it flickering, slowing down, speeding up, and generally being hard to watch. That would have been in the early 1930s.
> 
> ...


Try using domestic plug fuses... With dare, you may find a type with "machinable" ceramic... and use brown tufnol for the fuse board. If you want the simulated white ceramic, then you could try making a mould  (carve a wooden pattern and make a wax mould from it) and fill with dental filler as per dental caps. Or air curing pottery putty?
Just ideas, not proven. Or maybe your supplier of Electric components has glass fuses of a small enough size that you can paint with gloss white nail varnish?, so you only need to make knife switches and fuse holders?
K


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## Steamchick (Aug 31, 2020)

Shop shoe. I'm but a youngster, and don't  remember much of the '50s. But in the early 1970s I was in the Royal Navy reserve as a student, and we used to take a motor launch out for training. It had an electric cranked diesel engine that took 4 very large and heavy glass 6V batteries. Must have been 6 in x 8 in x 15 in tall! With heavy leather straps. Dropped into a wooden box (like a beer crate) and connected to make 24V. DC for the starter. Also in the 1970s and 80 s I knew of fork-lift trucks (stacker-trucks) with glass batteries.... so not so old.
Still in use, the 1930s hydro-powered generates at Fort William Lochaber power station. Check their website for big generators of a vintage style.
K


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## Ken I (Aug 31, 2020)

Rudy, I have also been thinking of a suitable generator - older DC servo motors often had a voltage generator attached (called a tachogenerator) - to give an analogue reference voltage output for speed - computing it was just too slow back then. Those generators were relatively large in diameter relative to length as well as a lot of poles - and would make a suitable starting point for an old fashioned looking generator.
I have over the years thrown many away - but of course now that I need one - I can't find one.
Murphys Law.
Regards - Ken


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## Steamchick (Aug 31, 2020)

I remember this guy having a decent generator for models oneb-ay a few weeks back... cringlemodelengineering so maybe he still has some stock?
Here's pictures of my Sturmey Archer double DYNOHUB Genset... Not quite authentic, but fun (for me anyway!). The rotor is a pair of external ring magnets - 10-poles each



 - mounted on the axle with 2 stationary 10-pole armature windings in the middle. A temporary engine fitted for first trial. $3 electronics for voltage control of DC output, after a full diode bridge converts each of the alternator outputs to DC and charges a capacitor bank. Set for 12V to power a 12V LED array, vehicle bulb (5W). Only needs 350rpm for the output, but I can run the generator up to 2000rpm  - with a proper steam engine fitted. (Maybe my SUN engine? - to be mounted in-line.).


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## Steamchick (Aug 31, 2020)

Lochaber power station genset.
1932 and still generating! Domestic power now that the Aluminium Smelter has closed (Second smelter built 1980 - I was there! -  closed 2006).
K


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## Steamchick (Sep 1, 2020)

Just a point of curiosity.... Coming from a mainly mechanical engineering background, but in the world of large electrical installations (power stations etc.), I have worked with Civil, Mechanical and electrical engineers. Many of whom seem to almost abhor the talents and subjects of their colleagues. e.g. the Mechanical and Civil guys don't understand electricity, the electrical guys often try and design mechanical things that are just too femur to be practical, and last. Now I know this is nit-picking, but some modellers do fantastic things and then fail to complete the job by not understanding the whole affair. I am referring to the odd wires connecting the brushes of the "dynamo" to wherever...
In most industrial generators of any appreciable size, which is often what modellers are trying to replicate, the Generator connections would be a short flexible connector (e.g. copper laminate or braid) to allow for assembly mis-alignment, vibration, expansion and contraction, which are then connected to BUSBARS. Those common and well used solid electrical connections that no-one appreciates. So while we make machines that are suited to a bit of 5 Amp flex wire, we should really be using 1mm x 5mm copper, or some such, to give a more accurate representation of the "real" job. Maybe with a very short link of the wire to replicate the flexible link, but these would always have been black - from the tar coated fabric insulation that was simple and common back in Eddison's day.
I berate myself for using 5A coloured plastic wire, so I look forward to someone doing a better job than I do! (Then I can copy it?). Maybe I'll paint the wire black? possibly wrapped in cotton thread? Ideas, please from Industrial Electricians?
keep writing and showing your excellent models (even if the windings are dummies, they look great!).
K


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## Steamchick (Sep 1, 2020)

Incidentally, the Lochaber generators connected in parallel at 320V DC and a total of 120,000 Amps to power the 80 Carbon-arc smelter cells at 4V each (in series) when the smelter was in action. The Busbars were effectively 6 bars 6in wide by 30 in deep aluminium... so cables were not an option. The busbars from generators to busbar gallery are under the floor. (Unseen).
Now the generators are used for domestic power, I guess there are some huge inverters to convert the DC to 3 phase AC for external power lines, and factory power for the new use. Anyone got any info?
K


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## BaronJ (Sep 6, 2020)

Steamchick said:


> Just a point of curiosity.... Coming from a mainly mechanical engineering background, but in the world of large electrical installations (power stations etc.), I have worked with Civil, Mechanical and electrical engineers. Many of whom seem to almost abhor the talents and subjects of their colleagues. e.g. the Mechanical and Civil guys don't understand electricity, the electrical guys often try and design mechanical things that are just too femur to be practical, and last. Now I know this is nit-picking, but some modellers do fantastic things and then fail to complete the job by not understanding the whole affair. I am referring to the odd wires connecting the brushes of the "dynamo" to wherever...
> In most industrial generators of any appreciable size, which is often what modellers are trying to replicate, the Generator connections would be a short flexible connector (e.g. copper laminate or braid) to allow for assembly mis-alignment, vibration, expansion and contraction, which are then connected to BUSBARS. Those common and well used solid electrical connections that no-one appreciates. So while we make machines that are suited to a bit of 5 Amp flex wire, we should really be using 1mm x 5mm copper, or some such, to give a more accurate representation of the "real" job. Maybe with a very short link of the wire to replicate the flexible link, but these would always have been black - from the tar coated fabric insulation that was simple and common back in Eddison's day.
> I berate myself for using 5A coloured plastic wire, so I look forward to someone doing a better job than I do! (Then I can copy it?). Maybe I'll paint the wire black? possibly wrapped in cotton thread? Ideas, please from Industrial Electricians?
> keep writing and showing your excellent models (even if the winding's are dummies, they look great!).
> K


Hi K,

Strip the jacket from some co-axial cable and remove the core ! There you have the braided wire for the flexible connections.


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## skyline1 (Sep 7, 2020)

Litz wire (used for R.F. coils) or fine high temperature wire with a woven covering both make good imitations of old cotton covered wires and are (fairly) easily obtainable

something like this HIGH TEMPERATURE 1.5mm FIBREGLASS WIRE 16AMP APPLIANCE CABLE HIGH TEMP PER METRE  | eBay might be good and it is probably available in smaller sizes

Best Regards Mark


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## Steamchick (Sep 7, 2020)

Thanks Baron, Mark, I am currently fitted with regular PVC covered wire then hidden by black heat-shrink... but as an ex-Busbar designer I felt I should do better! But thinking further, I should just make a housing to hide the visible bits anyway, as the busbars were housed.... so nothing is visible that is "under the skin". I have both TV aerial cable and some odd bits of High Temp braided insulation cable - so I'll dig that out. - Then hide it under some miniature trunking. Ahhh! I sense a godd night of sleep ahead!
K


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## miss_emma_jade (Sep 8, 2020)

jumping in late here. here's one I made, never worked as a dynamo for reasons that I now sort of understand. makes a nice little 6v electric style toy motor though!! id like to build either a manchester or Edison pattern dynamo tho again soon, probably a bit bigger this time, and with some better understanding of magnet steels and windings.


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## Manfred04 (Sep 8, 2020)

maybe you can find help in my ancient generator project. Dynamo build by castings
I start a new report soon, still have three generator/motor projects in progress.


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## TSutrina (Sep 8, 2020)

skyline1 said:


> Litz wire (used for R.F. coils) or fine high temperature wire with a woven covering both make good imitations of old cotton covered wires and are (fairly) easily obtainable
> 
> something like this HIGH TEMPERATURE 1.5mm FIBREGLASS WIRE 16AMP APPLIANCE CABLE HIGH TEMP PER METRE  | eBay might be good and it is probably available in smaller sizes
> 
> Best Regards Mark


Litz wire is for high frequency to deal with skin effect of current flow.  (as frequency increases the current decreases in the center of the wire.    Thus normal stranded or sold wire ad high frequency is not useful.   Main power lines put steel in the center to carry the weigh and aluminum or copper on the outside to carry the current.   This is at 50 or 60 Hz.


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## Steamchick (Sep 8, 2020)

TS. You are correct about the surface current. But as overhead HV wires mostly carry a relatively small current, and 50 or 60 Hz is low frequency, the steel is for strength. (I saw them made at BICC in Prescot works). Otherwise spans would be much reduced and cost increased by trebling the number of pylons. But for high current buried cables there is such a thing as an oil-cooled Miliken conductor (hollow centre) to exploit and optimise current versus material cost and maximise performance. I designed some at the BICC factory in Erith in Kent in the 1970s. Largest was a section for an Hydro-electric station in Canada at 100,000 kV DC. Can't remember the current. The conductor was  I later designed power station main generator busbars. Large tubes typically 0.5 to 1.5 m diameter with only 15 to 25 mm thick walls. Running at anything from a few kV to 33kV, and carrying  lots of thousands of Amps. Tubes used as only the outer "Skin" of the conductor carries significant current (electrons repel each other in the cross-section of large conductors). Due to high voltage of these bus bars they were in very large diameter Neutral enclosure tubes, section to carry the same (reverse) short circuit current ( >100,00 in some cases).
K


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## Steamchick (Sep 8, 2020)

Missed a bit as the page closed on me! 
Should read, " The conductor was hollow". Before I started waffling on about busbars....
Sorry.
K


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## Steamchick (Sep 8, 2020)

Miss Emma. A pretty little generator. I assume the winding in the middle is a rotating armature? 
Some Key points to generator design:

SMALL gaps between armature and stator. Can to reduce clearance to just a couple of thou, by changing the pole pieces?
High magnetic field. - Maybe you can insert some modern rare earth magnets between the u-shaped magnet and the pole pieces?
Speed. Can you drive it from (say) the perifery of a flywheel on a fast engine, to a small pulley on the generator? 
Roughly : Speed means voltage. Windings make current. (Thin wires resist current). More magnetic field helps everything.
Cheers! K


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## TSutrina (Sep 8, 2020)

Steamchick said:


> TS. You are correct about the surface current. But as overhead HV wires mostly carry a relatively small current, and 50 or 60 Hz is low frequency, the steel is for strength. (I saw them made at BICC in Prescot works). Otherwise spans would be much reduced and cost increased by trebling the number of pylons. But for high current buried cables there is such a thing as an oil-cooled Miliken conductor (hollow centre) to exploit and optimise current versus material cost and maximise performance. I designed some at the BICC factory in Erith in Kent in the 1970s. Largest was a section for an Hydro-electric station in Canada at 100,000 kV DC. Can't remember the current. The conductor was  I later designed power station main generator busbars. Large tubes typically 0.5 to 1.5 m diameter with only 15 to 25 mm thick walls. Running at anything from a few kV to 33kV, and carrying  lots of thousands of Amps. Tubes used as only the outer "Skin" of the conductor carries significant current (electrons repel each other in the cross-section of large conductors). Due to high voltage of these bus bars they were in very large diameter Neutral enclosure tubes, section to carry the same (reverse) short circuit current ( >100,00 in some cases).
> K


I got my knowledge from experience also.  I packaged aircraft generator systems and did some special projects including a 350HP induction motor feed by 1000 Hz three phase current created by an inverter I also packaged.  Rotor is about the diameter and length of a coffee can.  Steel lamination are thin and the best for high frequency.   Copper is very fine insulated wire.  Close to Litz wire.    I am aware of the reason for steel in the high power distribution lines.  It is possible because the current in the steel is low so resistance heating is not a problem.


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## HMEL (Sep 8, 2020)

I have been reading with interest many of these posts.  I spent a good share of my career in power plants that supplied steam or electrical energy to industry or the utilities.

There appears to be modelers who make intricate works of art based on actual equipment designs.  These work and are amazing in the skill required to construct them.  To do this with a generator would require finding one design you wish to copy and then modify the electrical side of the system.  Most generators require a good governor system as the generator has a specified number of poles which must be operated at a specified rpm to achieve the frequency of the grid its connected if its a utility connection.   I believe its very possible to achieve the looks but difficult to achieve the same function and be constructed in the same way. 

So what I would suggest is choose whether or not you want the looks of the system and then modify the electrical design to make power either DC or AC.

Its also quite possible to design a simple generator to make power for these model engines that perhaps do not resemble an actual unit but a functional unit that will generate power.

A simple AC generator can be made with magnets rotating on a wheel and the current rectified to DC.  This type of design would require no commutator. no exciter be simple in construction and would not require a restricted rpm. A proper term for such is probably an alternator but it would certainly add to the engines function and I suspect many would turn it into a nice piece of art as well as a functional model.  

You could with a little more work use an exciter as part of the generator and not use magnets.  Or you can make your own winding by hand. Making a small commutator is not impossible but could be more difficult even for a two pole system. An dc rotor with an exciter requires two concentric rings and is fairly simple.  It will require brushes to make the connection and the smaller the unit makes it a bit more difficult to maintain contact.

How big you make these models would of course depend the connected horsepower.  I know there are people who can calculate the developed current and of course there is the old fashion way of just build it and see what happens.  Just remember the engine has to be matched to the generator.

I look forward to see what is developed in this group.


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## Steamchick (Sep 9, 2020)

TS - Thanks for that interesting stuff! - I have never heard of the 1000Hz generators you discuss, as my "power stations" never flew or sailed anywhere.  e.g. Hartlepool and Heysham, Dinorwic, Lochaber and Dubai Aluminium smelters, plus large German Nuclear and Canadian Hydro, Oil rigs, etc....). Also, as "mine" were driving the grid, at 0Hz (DC), or 50 or 60 Hz. they were a bit simpler electrically. Anyway, we just "stuffed the frequency into the design equations and thought no more" (As it was fixed by the customer) and got on with the job of iterating designs to the achieve the optimum at minimum cost - Mostly for tendering. When the contract was gained, we had most of the parameters pre-determined from the tender design but then continued with all the components "at the standard design" for the installation. Incidentally, all the steelwork was designed with "electrical or magnetic breaks" in any E or M circuit adjacent to the busbars or cables. Efficiency calcs were very important to customers. Installations were checked to see that limits were not exceeded. (power out versus in, heating, etc.). Not quite necessary for models? 
Interesting work - and I met a lot of big Generators and Transformers on the way! (Later I spent a few years designing new HV power switchgear - sub-station kit).
I have wondered at the type of alternator - and frequency - used on modern Jets as they carry an engine in the tail that powers the generator... (The "bum-hole" - exhaust -  seen on the tail of most jets in airports! - I was in an airport once when a little kid told his Mum he could see the aeroplane's "bum-hole"! Kids for you...).
And have there ever been any Tesla Generators in service on something? Due to high revs, I am sure he was thinking of direct drive for his generator from his turbine (At around 100,000rpm?), but the contacts from the discs would possibly have been in baths of Mercury to minimise friction and heating? - I haven't ever seen a real version of the Tesla disc generator.
K


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## Steamchick (Sep 9, 2020)

I can't remember the calcs for Steel cored aluminium Overhead cables, but I'm sure they (as with everything) have internal as well as mutual inductance included - for heating, inductive and capacitive losses, as well as just resistive losses. - Yes, I'm sure I remember the inductive losses from the steel within the wires as the electric field from adjacent wires and cables of other phases causes inductive losses, as well as the single wire having an exponentially reducing electric field as you approach the centre (zero-field point). All this very significant when carrying power a thousand miles or more across Brazil! (Did you know they had capacitive "impedance correction" at intervals to keep the electrons from being stopped by Magnetic impedance of the length of the power-lines?). I digress:  Because cables (read: all conductors of any length, proximity) are made from "stock" materials and sizes, there were tables for different sizes of steel wire, and conductive outer that identified the current split - I guess for calculation confirmed by testing? Because the suspended wires use air and ceramic supports for insulation, we only had to consider the small amount of weather protective covering, spans, wind loading, mass, span length, etc. to complete all the calcs to prove a "sizing" from the standards made in the factory.
Don't ask - unless interested. I have reams of "not so interesting" stuff in my small brain... ("Boring!" - according to my missus).
K


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## miss_emma_jade (Sep 9, 2020)

Steamchick said:


> Miss Emma. A pretty little generator. I assume the winding in the middle is a rotating armature?
> Some Key points to generator design:
> 
> SMALL gaps between armature and stator. Can to reduce clearance to just a couple of thou, by changing the pole pieces?
> ...


yes. well aware of most of these things now.. lol there's about 10 thou gap, which is too much. the magnet was a dismal failure, so I rebuilt it in aluminium and imbedded two rare earth magnets at the poles. some finer windings on the armature might have helped. I know next time it might be a lot better. some wrought iron bar to make a permanent magnet out of would be even better. almost impossible to find though in 2020.


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## Steamchick (Sep 9, 2020)

I have used an old file for hard steel for a permanent magnet. (HIGH remanence). Needs to be cooked red and cooled slowly to anneal before you forge it, shape it, machine it etc. Then red hot and quenched to harden it for permanent magnet molecular state. Then clean and magnetise in a coil with DC applied.
Soft iron is used for alternating magnetic fields (low remanence).
Your modern magnets are probably a stronger field though, but could be connected by a hard steel u-shape, not aluminium.
Enjoy!
K


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## peterl95124 (Sep 9, 2020)

I designed and built this replica Edison Bipolar Dynamo to deliver 12V at 1200 RPM, to go with my Stuart #9. If there is enough interest I will publish the design, and the design calculations so it can be scaled and adapted to suit the builder.


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## deeferdog (Sep 10, 2020)

I would be very interested and pleased if you made them available. Cheers, Peter.


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## BaronJ (Sep 10, 2020)

Hi Guys,

Its a pity that there are not more generator designs and plans around.

I think that the problem is that to most people electricity and generators are very much akin to black magic !


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## miss_emma_jade (Sep 10, 2020)

peterl95124 said:


> I designed and built this replica Edison Bipolar Dynamo to deliver 12V at 1200 RPM, to go with my Stuart #9. If there is enough interest I will publish the design, and the design calculations so it can be scaled and adapted to suit the builder.


thats very nice. would love to see more.


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## bdolin (Sep 10, 2020)

If output voltage is the main consideration, a simple DC pm motor will work well- think Mabuchi- easy and cheap
Model dc brushless motors are 3 phase with rare earth magnets and should also worK, some are very hi power in motor use


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## Richard Hed (Sep 11, 2020)

peterl95124 said:


> I designed and built this replica Edison Bipolar Dynamo to deliver 12V at 1200 RPM, to go with my Stuart #9. If there is enough interest I will publish the design, and the design calculations so it can be scaled and adapted to suit the builder.


Yes, I am always interested in any type of generator or even alternator, dynamos, etc. plans


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## tonyr769 (Sep 12, 2020)

I would also be very interested in the design and calculations for an Edison generator. They look very good being driven from a horizontal engine.


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## miss_emma_jade (Sep 12, 2020)

Im looking very closely at drawings and information in the first 3 ME magazines in 1898. there's a tidy little overtype dynamo that promises 8v. there are three iron castings and an armature made out of "charcoal iron" pressings. it has about a 1.5" armature and runs at 3500 rpm .


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## miss_emma_jade (Sep 12, 2020)




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## BaronJ (Sep 12, 2020)

miss_emma_jade said:


> View attachment 119292



Hi Emma,

That is a very nice rendering !  Thanks.

Somewhere I have a picture or two of real generators that I've taken in a museum.  If I can locate them I'll post them.


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## BaronJ (Sep 13, 2020)

BaronJ said:


> Hi Emma,
> 
> That is a very nice rendering !  Thanks.
> 
> Somewhere I have a picture or two of real generators that I've taken in a museum.  If I can locate them I'll post them.



Hi Emma,
This is a picture of a three phase alternator that I found last night.  Its a picture that I took of an early generator set up that is on display in the Bradford Industrial Museum a year or so ago.

From memory a DC machine is also driven by the same engine. The alternator is run at 3000 rpm, the DC generator, which is run at a reduced speed, by means of a "V" belt and different size pulleys.

The DC generator is the machine at the front.

I've some more pictures that I will post when I find them.





Note the rather crude DC wiring coming out of the alternator. The DC generator providing the field power.  The three phase is the cable on the floor to the left below the machine.

I've just found another picture of this !


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## Steamchick (Sep 14, 2020)

Good stuff! As you say... the wiring appears to be a mechanic's "fiddle and bodge"... but may have been the correct wiring for the era....? Ever owned a 1950's motorcycle? I have had half a dozen, but it seems that until the 60s (Unitised engines and cleaner lines), the wiring "just happened to be where it was".
It appears to me that the dynamo looks big just for excitation? All that machine into those tiddly wires? But maybe the 3-phase voltage control was done by the field control of the dynamo, or those wires may not have come directly from the dynamo but from a battery (charged by the dynamo?) via an independent 3-phase voltage controller? Do you know which Museum?
K


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## BaronJ (Sep 14, 2020)

Hi K,



Steamchick said:


> Do you know which Museum?





BaronJ said:


> Its a picture that I took of an early generator set up that is on display in the "Bradford Industrial Museum" a year or so ago.


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## KellisRJ (Sep 14, 2020)

Rudy said:


> No luck so far.
> Anyone seen anything like it ?
> Rudy


Rudy, I was looking at the digest and saw a thread on a 1963 Popular Mechanics engine. At the same web site that had hosted those plans I spotted this
The First Green Steam Engine Generator
Ron


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## Steamchick (Sep 14, 2020)

Good model! But to improve it, how about replacing the aluminium base with a copy of the top half - complete with magnets to increase the magnetic field? I guess a good few thousand rpm are needed to get any decent power out, so max field strength will help? Minimum clearance between armature and stator is needed, every thou of air gap saps magnetic power...
K


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## miss_emma_jade (Sep 15, 2020)

Steamchick said:


> Good model! But to improve it, how about replacing the aluminium base with a copy of the top half - complete with magnets to increase the magnetic field? I guess a good few thousand rpm are needed to get any decent power out, so max field strength will help? Minimum clearance between armature and stator is needed, every thou of air gap saps magnetic power...
> K


which were you talking about?


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## Steamchick (Sep 15, 2020)

Sorry Emma, I was referring to the "first green steam engine generator" link.
K


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## Steamchick (Sep 15, 2020)

I hadn't spotted  your 1898 generator. As that has an iron loop including the armature, with field coils, it doesn't  need the permanent magnets.
Nice big of CAD! (I am a paper and pencil man, so no where near as good!).
You could design an alternator? There are many Home-made wooden armatures holding rings of modern strong magnets as armatures, then using coils on the perifery (stator). If you made a small aluminium cored armature with permanent magnets, you could easily configuration a ring of coils and fit the whole in a simple case to look like an alternator  - something like the Bradford museum pictures already posted? Whatever takes your fancy! That's what it is all about.
K
K


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## BaronJ (Sep 15, 2020)

Hi Everybody,

I've found another couple of pictures !






This one is on display in the Enginuity, a museum in Iron Bridge, Telford.  Just a few hundred meters away from the Iron bridge itself.  There isn't a description plaque, so I don't know if this is a generator or a motor. Either way it appears to be self exited with an adjustable brush gear. The rotor/armature is about 5 feet long.





This one is in the Blists Hill town museum, again in Telford.  I couldn't get close enough to clean and read the label on it.  It appears to have three stationary electromagnets and an armature with a row of four brushes in three sets of very heavy duty brushes set at 120 degree intervals around the commutator.  Again one set of four brushes seems to be adjustable.  This machine is only about four feet long, the round housing is about 2 feet in diameter.  The base about 20 inches wide.

Next time I go there I will ask if I can be allowed into the area to take some more pictures.  Because I think that this one is particularly interesting.

If I find any more pictures I will add them.


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## miss_emma_jade (Sep 22, 2020)

I have a new printer, so I printed this to see how it looks on the bench. not sure if I'm planning my next project or not yet, but its very doable.


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## Steamchick (Sep 23, 2020)

Looks fine - progressing well!
Keep up the good work.
You may find the attached of interest? (I could not understand it all).
K


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## miss_emma_jade (Sep 24, 2020)

Steamchick said:


> Looks fine - progressing well!
> Keep up the good work.
> You may find the attached of interest? (I could not understand it all).
> K


might take some time to digest that


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## BaronJ (Sep 24, 2020)

miss_emma_jade said:


> might take some time to digest that


 I agree !  Its heavy reading.


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## BaronJ (Oct 1, 2020)

Hi Guys,

I promised that I would add any more pictures that I found of old motors and generators here.

This one is another self exited generator and can be found in the Black Country Museum, near Birmingham, UK.






Notice that someone has put a shorting link across the coils.  I bet someone got a tingle from that.

Its also on mounting rails so the belt tension can be adjusted, though I suspect that the drive pulley is not the original one.






All this style machine seem to have adjustable take off brushes. These are very large carbon ones with heavy spring loaded arms pressing them on to the commutator, a pair on either side.






I do like the oil drain tap and oil box on the top.  There is one at both ends of the machine, the armature shaft running in bronze bearings.

I think that this machine would be a good candidate for a model, simply because of its simplicity.  Unfortunately there doesn't seem to be any information as to who made it or when, or to its output.


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## Misterg (Oct 1, 2020)

BaronJ said:


> Unfortunately there doesn't seem to be any information as to who made it



Nice.

What does the lettering cast into the base say?


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## BaronJ (Oct 1, 2020)

Misterg said:


> Nice.
> 
> What does the lettering cast into the base say?



Good Lord, I had to go and study the pictures !  I totally completely missed that .  When I next go down there I will make a point of photographing that part of the machine.

My sincere apologies.  At the time of taking the picture it never occurred to me to look on the base there. 

Thank you for pointing it out !


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## Misterg (Oct 1, 2020)

BaronJ said:


> Thank you for pointing it out !



No worries! - I spent a little while trying to enhance the image to be able to read it, but it just doesn't work like it does in the movies...


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## Steamchick (Apr 24, 2022)

Hi Emma, What is your latest creation?
K2


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## animal12 (Apr 24, 2022)

Cool Pic's . Is that a motorcycle in the background in post 66 ?
animal


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## alanganes (May 6, 2022)

The old book "The Boy Electrician" by Alfred Powell Morgan included plans for a small 10 Watt model dynamo somewhat similar to the Edison unit in post #16. The book is old enough to be in the public domain so you can find PDF's of it on the web. I have an old hardcover edition around here someplace. The plans call for castings, but I expect the clever types around here could come up with workarounds for that. 

I'm pretty sure I have seen similar model dynamo plans in similar old books.


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## GreenTwin (May 6, 2022)

Can be downloaded for free in PDF format here:








						The Boy Electrician by Alfred Powell Morgan
					

Free kindle book and epub digitized and proofread by volunteers.




					www.gutenberg.org
				




.


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## TonySteamHobby (May 8, 2022)

These were at the steam/gas tractor show last weekend…
I have some close-ups if interested…


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