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The Vermont Garden Railway Society has an informal live steam subdivision which meets (approximately) weekly during the short Vermont summer. We normally use Larry Green's layout because it has two concentric loops and is up on benchwork. We use my layout infrequently because it has a sigle loop and is mostly on the ground.
At our 15 October get-together, Larry noted that my K28 seemed to be a strong puller and suggested that we put it to the test. We hooked on five AMS J&S coaches and twelve freight cars. (Sometimes it seems as if AMS coaches are about as easy to pull as dragging a concrete block across your basement floor). I got pressure up on my loco, coupled onto the train and sent it on its way. The drive wheels never slipped. I did find that it started to run out of steam; so, I turned the flame up to get a higher pressure and the loco marched onward without complaint.


Larry was running his Accucraft 4-4-0 American with string of empty ore cars. Here you see it prancing on by the more heavily burdened K28.


There could be another day or two in October when it will be possible to steam; but, it looks as if time has nearly run out for this season’s steaming.


Llyn Rice
 

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Llyn, My grandson recently used my K-27 and freight cars for a 6th grade science experiment to prove his hypothisis that an increased load results in a decrease in energy efficiency. He was very prepared and had obviously paid attention in class. He weighed each of my freight cars and grouped them into 5 groups of 4 cars weighing 15.5 pounds a group for a total of 77 pounds for all 21 cars (not icluding the tender). After a baseline run with one speedometer car, he added one group at a time until he was pulling 21 while taking time and distance measurements at each run. His constants were 60 psi, 30 mph (via a scale speedometer in a combine), level track and a measured amount of water added to the boiler for each run (using starting and stopping indicators on the sight gauge). His controls were the pressure gauge, the speedometer, a calibrated water syringe and the water level sight gauge. The K-27 had no trouble pulling the 21 cars even with loads on some of them (pebbles in the gondolas to even out the five groups). Given the performance, I think I could have added my 5 Jackson Sharp cars and the K-27 still would have pulled the lot. I can't remember how many cars there were, but I once saw a K-27 easily pull a string of cars in Colorado that nearly went all the way round the DGRS steam track. I imagine it was 40+ or so. I was very proud of his project planning and also glad that my K-27 did the job and didn't crap out. I took the last of the video he took for the project and made a short YouTube movie:

http://www.youtube.com/watch?v=VvvXI7asXxQ
 

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Discussion Starter · #3 ·
Hi Carl,

Was Henry able to show his hypothesis to be correct when he finished collecting and analyzing the data?

The Accucraft K series locos do seem to very strong pulling machines.

Llyn
 

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Henry is still analyzing the data and preparing 3 graphs, which he has to turn in on Wednesday. He will make a projection from one of the graphs to determine at what point the K-27 can pull no more cars. He thinks his graphs will permit him to prove his hypothisis.
 

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After a few trips around and the photos, Llyn removed the freight cars and continued to run the K with just the five J&S passenger cars. Likewise, I have loaded up my 4-4-0 on occasion also, without having made it slip so far. However, we don't think it a good idea to routinely run our engines to capacity, nor at exceptionally high speed. Such activity can be very hard on the motionwork and, with the probable lack of long-term repair part support from Accucraft, rebushing rods and pin replacement becomes pretty much a do-it-yourself project. Not bad on an engine like the 4-4-0, but I wouldn't relish doing it on a CF.

The combine was made from a plastic J&S coach. I wanted something different than the generic version that will sometime appear from Accucraft. These cars are great kitbashing fodder. I neglected to put BB's in the trucks, but that is on this winter's shop list.

It is currently 43 degrees and raining, with snow forecast for tonight in higher elevations. Guess steaming on the Belden Falls is coming to an end for this season.

Larry
 

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Interesting experiment but there are too many variables left unattended to come up with a reliable answer. For starters in the video the safety is just roaring so energy is being wasted. The locomotive is most efficient if pressure is kept just below the pop off. The the out side temperature greatly affects these little locomotives. So as the day heats up the engine becomes more efficient in that it takes less fuel to boil the same amount of water. Anyway, I would think the answer would be the exact opposite. If you have a large locomotive, it is still burning fuel and having to haul it's own weight even with a light load. So the heavier the load up to the slipping point the more efficient it becomes as long as you aren't wasting steam by having the safety constantly popping off. You are after all, boiling the same amount of water so you are putting the same amount of steam through the cylinders to haul each load. As the load increases you have to increase the throttle, but these locomotives don't have cut off so the valve timing is the same no matter what you do. Interesting to see what Henry comes up with.
 

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For gosh sakes, John, it's not a laboratory experiment by pros, it's a 6th grade science lesson by a 11 year old who came up with the scheme by himself. Given all the uncontrolled variables, it looks like he'll prove his point anyway. Most kids in his class didn't come near to his complicated plan. I'm just elated that he wanted to use my train and track for his school work. He's a future steamer.
 

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Posted By weaverc on 10/22/2008 5:45 AM
For gosh sakes, John, it's not a laboratory experiment by pros, it's a 6th grade science lesson by a 11 year old who came up with the scheme by himself. Given all the uncontrolled variables, it looks like he'll prove his point anyway. Most kids in his class didn't come near to his complicated plan. I'm just elated that he wanted to use my train and track for his school work. He's a future steamer.


Well Carl I'm just a 'bean counter' not a physicist(I can't even spell it) so I really don't know what the real answer is. I really resent being jumped on for posting here however. I am not an idiot, I know he's just a boy doing an experiment. But since you decided to bring it up and post it all over here I just had some questions. Sorry you got so offended.
 

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John, Although you bring up some good points, I think your wording in you post gives the reader the impression you were being mean spirited. ( Some of us know better ) I think "the safety is just roaring" sets the tone. It is a challenge to find that "sweet spot" in any given run, balance between the fire, axle pump by-pass, weather conditions, and loads.
So If one is after the most efficient use of their fuel looking for the longest run time, a light load is more efficient to achieve that end, however if "work done" is the goal then, finding the most efficient load, speed,burner setting, cut off etc. make it a bit more complex... Henry seems to be after efficient use of WATER, in his experiment? To that end, standing for a long time with the safety open will skew his findings as you were pointing out.
 

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Kevin,
It's scratch built using plastic truck frames (I think Bachmann) and metal wheels. I used some old plans I had laying around that I'm not sure where they came from. They might have been NE Narrow Gauge, but not sure. I've installed a WalMart bicycle speedometer that has been calibrated to 1:20. You can just make it out in the left hand window. I built it small to look good next to an AMS box car and not long and big like the Jackson Sharp cars. It has battery driven internal lights including an LED over the speedometer face. It's a good roller. I used David Bailey press on decals.

 

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Kevin,
Sorry, that was a little presumptive on my part. I notice that it says below that Larry Green kitbashed that from a J&S coach. Very clever. I'd like to know more about it also since it will be along time until AMS releases their combine.
Larry,
Please start a thread in Rolling Stock on what you did.
 

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Hi Llyn
The NHGRS also has a steam division. We call it the Real Train Division. The reason I am responding is that we also have a monthly steamup with members and non-members and maybe we should get together next steaming season. We meet at different railroads from northern Ma, Nh, and Me. Don Jackson(Me) is putting together our schedule for next year and when I get it I'll send a copy to you and maybe we can get NH and VT steamers together next year. I lived in Stowe for a number of years and moved to Bow NH 10 years ago. The winters in Vermont got to cold, especially after I couldn't ski anymore. Let me no what you think about getting together next year.

Dave Barker
NHGRS-RTD
 

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Discussion Starter · #17 ·
Carl,

Larry doesn't do photos on MLS. After I shake the cold I'm suffering from, I'll arrange to photograph his kit-bashed combine and start a thread which he can amplify.

Dave,

Next year seems like such a long way off for planning purposes. But, please do let us know what you have going next summer. A joint get together could be fun.

Llyn
 

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Llyn, now I know why you haven't emailed me about when we were to steam this week.
To all, since I am somewhat computer illiterate and don't own a digital camera, Llyn has been appointed as official Belden Falls Branch Ry company photographer. It's payback for trackage rights on the BF for his K. I will give him the combine assignment once he is ready to get back to work.

Larry
 
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