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| rangerssteamtoys |
FrictionWell i'm doing my science project on steam and generating electricity with my stepper generator. I have never really noticed how big a difference it makes when........1. You add another flywheel, did this with my jensen 5 and got 14 volts top. without it the voltage was about 7.5. Inertia I guess 2. The difference a driveband makes, I used a short rubberband with my 25 and never got good results switched to a longer one and the max was 32 volts  but settled at about 17.
My project was about which engine would be better, the jensen 5 of the jensen 25. Well the 25 won of course. Even though it has alot more gizmos that add friction it still won. The jensen 5 was a lost, can anyone explain why? Same cylinder bore and boiler. just not enough power I guess? It get some high RPMS though. So I bet this proves that slide valve engines have more power than oscliators. For some reason I feel that I'm poking a hornets nest with this post since we got all these die hard mamod men. |
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| Mamodman123 |
Does it not just proove you can get more power from a slide valve? | ||||
| rangerssteamtoys |
Better or more power which ever. Eh maybe more power 
time to edit |
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| Mamodman123 |
To say something is better is a matter of opinion I guess! But i'll openly admit that slide valves are more powerful, thats the point isn't it? Wonder how you got double the power by adding another flywheel?
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| rangerssteamtoys |
Well if I were to make a good edumacated guess 
I would say inertia, somethings resistence to accelerate or decelerate. I noticed that at first the voltage went down to about 10 volts then about 5 minutes later it was up at 14. So over time it sped up a bit and stayed there, also you can consider the boiler got up pressure when it was slow then sped up overtime.  Just a guess but something tells me that thats it.
heres a link to the second flywheel video http://www.youtube.com/watch?v=z6f4KnZQ7LA |
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| johnreid |
Although more complicated, and higher tech ( just not 21st Century High Tech ) , the Stephenson Valve gear is much more efficient than the Oscillator. The Oscillator wins out for simplicity though.
Now, can someone explain the difference between Stephenson and Walschaerts? |
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| Mister Occlusion |
http://en.wikipedia.org/wiki/Walschaerts_valve_gear
Mind you, I don't understand it 
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| SillyBilly |
I get bits of it! Should of completed it by the time I'm 16! | ||||
| johnreid |
I hate to admit that when I look at the info on Stephenson and Walschaerts and try to tell the difference, I have a senior moment. I believe that the Walschaerts came later didnt it? Only here would we be talking about High Tech and the words Stephenson and Walschaerts would be in the Topic.
Is the Stephenson reversed via a linkage and a second Valve Rod and the Walschaerts done via the Steam Valve? Where did I put those Tylenols? |
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| Mister Occlusion |
I just look at the pretty animated gifs until my eyes start to spin... takes about 11.23 seconds +/-... | ||||
| SillyBilly |
On Bagnall locos, you can get Bagnall-Price valve gear, which is truly a beautifel object! | ||||
| johnreid |
I was going to add that there are other factors that would give one engine more HP than the other such as timing etc. | ||||
| Titan |
Stephensons requires two eccentrics to drive each valve, ie two pistons 4 eccentics and so on. Walschaerts needs only one, ie 2 pistons 2 eccentrics. Thats really the principle difference. |