Scratch building the Hicks Oscillator

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Hi Deeferdog.
On generator control...
Dynamos (like yours) usually have field control to limit the field as necessary to hold the voltage at or below the set value. But you could "let it just rise" - then feed a capacitor, after which you extract the power with a small dc -dc buck controller that delivers all the current the load wants at the voltage you determine at a pre-set level.
As my generator is an AC device, I fed a large capacitor from the rectified uncontrolled generator, then used the DC-DC buck controller to give the output voltage I want, and it simply takes all the current the lamp needs without worries.
But first you need to check how you dynamo generates at the desired steam engine speed.
Cheers!
K
 
I forgot to mention: I had buckets of ideas from HMM members - without whom I could not have done the Voltage control on my generator the way I have done. MANY THANKS TO ALL THE EXPERTS WILLING TO HELP. - So I am not an expert at electrics.
I'm looking forward to hearing how you control your dynamo, and how it performs. It looks like the innards of a mains powered hand tool - a drill or something? - Was it a mains series-field motor that you are connecting as a parallel-field dynamo? I have a few for conversion myself.... I suspect they won't develop any reasonable volts at "Steam engine speeds" - like your Hicks Oscillator. I have a Stuart Turner Sun engine I plan tocombine with a suitable gerator... when I get around to it. That's a 1000~2000rpm twin SA engine for those who haven't met one. So should be better for genrating as the generator speed can be more direct to the engine speed. I guess the Hicks is running arounr 300rpm in the video? - So will need to gear-up to the dynamo quite significantly? Lots of engineering (and whisky?) here I suspect.

K
 
Well, I've been involved with other things, so this hasn't been given my best shot. However the progress so far is as follows:
With a 6 volt light bulb connected across the output terminals, 5 amps of field current at 18 volts and the steam engine going flat out on compressed air at 90 psi, if the shed is very dark and you peer intently, it can just be discerned that the filament of the globe is glowing a dull red. This is not going to solve any energy crisis or do my ego much good. Now, where did I put that bottle? Cheers Peter.
 
Well, I've been involved with other things, so this hasn't been given my best shot. However the progress so far is as follows:
With a 6 volt light bulb connected across the output terminals, 5 amps of field current at 18 volts and the steam engine going flat out on compressed air at 90 psi, if the shed is very dark and you peer intently, it can just be discerned that the filament of the globe is glowing a dull red. This is not going to solve any energy crisis or do my ego much good. Now, where did I put that bottle? Cheers Peter.
Something is wrong then, if everything was working correctly, you would most likely burn that 6v lamp out in the instant you switched it on.
 
Deeferdog, Just a few comments - my apologies if I'm stating the obvious but.....

The image of your generator at the bottom of post #86 shows the field coils shunted to the commutator brushes - this will never self-excite as the field has no residual magnetism.

Based on your further comments, you have subsequently chosen to externally excite the field windings.
You are supplying 18V @ 5A to the field but getting nothing out of the rotating armature - three possible problems (same apology) :-

1) Are you feeding 18V DC or AC ? it must be DC

2) You may inadvertently have the fields in opposition resulting in no field being generated - try reversing the connection of one of the field coils.

This might be the case and the miniscule output that you are getting is because of some tiny difference between the two coils.

3) The orientation of the brushes - it looks incorrect but is that the orientation in the original power tool or at 90° from the current plane - could be so by a rather unconventional armature wind. It's more usual to see the brushes in line with the field plane.

If so you are commutating at zero (minimum) voltage portion of the cycle.

Don't try rearranging them just run your voltmeter probes on the surface of the rotating commutator at 90° to existing plane and see what you get.

If that is the problem, you can fix it by rotating either the brushes or the field stator - which I suspect would be easier.

As Richard said - I would also expect to blow the 6V lamp with that rig.

Assuming you get it sorted out, you can probably make it self exciting by adding a pair of NiB magnets to either side of the stator - obviously matching the polarity when excited - otherwise it will simply extinguish itself.

Having said all that, I think the concept is really cool and I'm looking to do something like that myself.

Regards, Ken
 
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Ken I has been a help to me, and I agree with his advice.
But I would suggest you first get a compass and - with armature removed - check the polarity of the pole pieces, You'll only need a few volts (I guess 4~6V will give you 1 amp or so in a field coil and adequate magnetism) to determine the polarity of the individual pole? But remembering simple electromagnetism: Volts come from a rapid rate of change of the magnetic field. So if the gearing isn't getting the armature to a few thousand rpm, I doubt you'll actually generate many volts - even with the field that you should have at 5A. If unsure of checking things with a compass, just excite a single pole (leaving the other one un-excited = open circuit) and then check for volts on the armature? Then do the second field coil instead and see if the voltage is the same - or reversed? They need to be the same... But if neither field coil gives volts from the armature, then Ken I's full methodology is necessary.
Hope you can follow this and it helps?
K2
 
To check out the polarity just insert a rod that is a little shorter than the bore diameter - turn on and it should snap to attention between the poles - if is snaps over sideways you have like poles facing. (edit: the rod must be iron / paramagnetic material.)

Just a quick and dirty method.

Regards, Ken
 
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Just come across this thread, being a relatively new member, and found your build log and final engine really interesting. I note all the comments about the possible lack of interest; and for what it’s worth I think many members read posts without actually commenting. I’m trying to get into the habitat of at least using the “like” button.
Personally I am hooked on steam engines and find them fascinating. I started with a Stuart 10H, then Tubal Cain’s Lady Stephanie Beam Engine and now I’m on with Merryweather Fire King (also from drawings by Julius da Vaal). Another very important point about this forum is that there is a wealth of experience here and always someone to answer the questions from a beginner like me.
Cheers
Bob
 
Thanks, in particular to Ken and Steamchick, and all the others who took the time to show interest in this thread. I have been busy, involved in the erection of a simple carport with my neighbor. Both of us have been at great pains to demonstrate to each other our extensive knowledge of the building industry and as a consequence have lost sight of the original project, we are now reduced to actually having to peruse the instructions to determine just what went wrong with a structure that consists of four posts and a roof. I just cannot wait to get back to my shed. I will post on this and any other disasters as they present themselves. Is it any wonder that I occasionally have been known to have a drink? Cheers, Peter.
 
Why did they ever call building work "Civil" Engineering? Possibly because it was financed by the "Civil Authorities"? - though many have thought it quite un-civil!
First rule of Civil Engineering.
Unless you are in profit when you have completed the foundations and get above ground level, you can never make a profit from the stuff above!
Second rule:
From the moment you dig the first Sod, every other sod you think you will encounter, and all those Sods you couldn't imagine encountering, will appear to undermine your good works!
Third rule of Civil Engineering.
Work out the cost of ground-works, then double, then imagine the absolute worst case - re-do your estimates, and double that - and add all the estimates together and you stand a chance of a profit at ground level. For works above ground level.
Work it all out - then double it, and add the margin you need on top - then a good percentage for profit, then double all of it! That way you stand a chance of recouping costs that the architects will naturally incur by their lack of Engineering ...
Fourth rule of Civil Engineering: Don't do it. When it goes wrong, you'll be the one hanging from the rope wondering what happened so quickly!
Good Civil Engineering: Something that doesn't fall down in your lifetime, and made you a profit.
As to the car port, why didn't you get a "builder" to do it? - then he could make it fit when it otherwise wouldn't, despite all the calculations and checks to be sure it would be OK.... - Just never watch what builders do... - it makes me cringe - but they somehow manage to finish jobs to look OK..
Finally, the only group of alcoholics I have worked with were all Construction Site Agents.... They could all drink 2 bottles of whisky after a good finishing day, when the customer signed-off the job, before they went out to celebrate! (As I didn't drink, they sent me for the extra 6 bottles of whisky after the first 6 had evaporated, then I took all 6 to the pub... and collected them to take them home 6 hours later!).
Old Civil Engineers never die, they just get pickled ...
K2
 
Incredible work. I too have completed one from castings. Yours is Waaaay better. Beautiful. Thanks for sharing.
 
Why did they ever call building work "Civil" Engineering? Possibly because it was financed by the "Civil Authorities"? - though many have thought it quite un-civil!

Not that you were asking, but in Roman times there were only military engineers and -- civil engineers. That was it. Military engineers took out targets, civil engineers built them, if you needed something mechanical you went to a blacksmith, and electronics didn't exist.
 
Why did they ever call building work "Civil" Engineering? Possibly because it was financed by the "Civil Authorities"? - though many have thought it quite un-civil!
First rule of Civil Engineering.
Unless you are in profit when you have completed the foundations and get above ground level, you can never make a profit from the stuff above!
Second rule:
From the moment you dig the first Sod, every other sod you think you will encounter, and all those Sods you couldn't imagine encountering, will appear to undermine your good works!
Third rule of Civil Engineering.
Work out the cost of ground-works, then double, then imagine the absolute worst case - re-do your estimates, and double that - and add all the estimates together and you stand a chance of a profit at ground level. For works above ground level.
Work it all out - then double it, and add the margin you need on top - then a good percentage for profit, then double all of it! That way you stand a chance of recouping costs that the architects will naturally incur by their lack of Engineering ...
Fourth rule of Civil Engineering: Don't do it. When it goes wrong, you'll be the one hanging from the rope wondering what happened so quickly!
Good Civil Engineering: Something that doesn't fall down in your lifetime, and made you a profit.
As to the car port, why didn't you get a "builder" to do it? - then he could make it fit when it otherwise wouldn't, despite all the calculations and checks to be sure it would be OK.... - Just never watch what builders do... - it makes me cringe - but they somehow manage to finish jobs to look OK..
Finally, the only group of alcoholics I have worked with were all Construction Site Agents.... They could all drink 2 bottles of whisky after a good finishing day, when the customer signed-off the job, before they went out to celebrate! (As I didn't drink, they sent me for the extra 6 bottles of whisky after the first 6 had evaporated, then I took all 6 to the pub... and collected them to take them home 6 hours later!).
Old Civil Engineers never die, they just get pickled ...
K2

Hi Steamchick,

That sounds like a certain President's version of civil engineering but you missed out the bit where you declare bancruptcy to avoid paying your contractors or taxes.

TDx
 
Why did they ever call building work "Civil" Engineering? Possibly because it was financed by the "Civil Authorities"? - though many have thought it quite un-civil!
First rule of Civil Engineering.
Unless you are in profit when you have completed the foundations and get above ground level, you can never make a profit from the stuff above!
Second rule:
From the moment you dig the first Sod, every other sod you think you will encounter, and all those Sods you couldn't imagine encountering, will appear to undermine your good works!
Third rule of Civil Engineering.
Work out the cost of ground-works, then double, then imagine the absolute worst case - re-do your estimates, and double that - and add all the estimates together and you stand a chance of a profit at ground level. For works above ground level.
Work it all out - then double it, and add the margin you need on top - then a good percentage for profit, then double all of it! That way you stand a chance of recouping costs that the architects will naturally incur by their lack of Engineering ...
Fourth rule of Civil Engineering: Don't do it. When it goes wrong, you'll be the one hanging from the rope wondering what happened so quickly!
Good Civil Engineering: Something that doesn't fall down in your lifetime, and made you a profit.
As to the car port, why didn't you get a "builder" to do it? - then he could make it fit when it otherwise wouldn't, despite all the calculations and checks to be sure it would be OK.... - Just never watch what builders do... - it makes me cringe - but they somehow manage to finish jobs to look OK..
Finally, the only group of alcoholics I have worked with were all Construction Site Agents.... They could all drink 2 bottles of whisky after a good finishing day, when the customer signed-off the job, before they went out to celebrate! (As I didn't drink, they sent me for the extra 6 bottles of whisky after the first 6 had evaporated, then I took all 6 to the pub... and collected them to take them home 6 hours later!).
Old Civil Engineers never die, they just get pickled ...
K2

P.S.
you don't have to be civil to be civil, just think of the civil servants you have dealt with over the years. Some very uncivil people there!

TDx
 

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