Greetings all OK, because of trainboard, I bought a book to help me with track and layout planning.. it was John Armstrongs book Track Planning for realistic operation.. wow what an excellent book... anyway I digress.. My new trackplan, also much better as a result of people here, has an off-scene.. at the moment.. classification yard. Last night I was doing some thinking about the modelling of this when I get there. I know. I should be careful at my age, and looked at two items in John's book... The hump yard and the Car Dumper yard, both of which operate semi-automatically using grades and ramps. My question is.. does anyone know if either of these have been accurately modelled as working examples in N-guage? I was doing some mathematical modelling on the computer last night, and although the tolerances for weight and roll on the bogies would have to be quite carefully maintained, it seems to me there is enough latitude to make it a working example without resorting to having to roll the wagons at 75 mph to make it work.. scale speeds of 5 - 10 mph should be possible if the cars are all weighted correctly. It's scary when the brain starts dashing of down paths like this, you never know what will be the result. Regards [ 24. February 2004, 15:00: Message edited by: Graham Evans ]
I've always thought about this scenario, as I'm sure many others have. I would think an innovative approach would be to have your cars catologued into a computer with variables included that could tell your "retarders" how to handle each car on your layout. So, for example, let's say you had a cut of 10 cars to hump. Your car order software would have that list of cars in a database, and each car would have several variables, including weight and "rolling quality" which could be a number between, say, one and five that would be based on a series of benchmarks that each car would have to endure. THEN, using retarders (probably air, or some kind of axle-based system with motorized flexible plastic picks between the rails that would raise and lower to slow down the cars...think "plastic dental pick") you would know how much retarding to apply to get the car where it needs to be. So, in this scenario if car one weighed 3 oz. and had a rolling quality of 4, the computer would tell the retarders to apply 4 of a possible 5 slow points to ensure the car glides to a stop within it's specified range given the number of cars already present on the selected bowl track. You could possibly go a step further and have some kind of automatic car identification, maybe a magnetic stripe reader? This would let you hump on the fly, so to speak. Obviously this is a pretty complex way of doing it, and you could probably do just as well having a manual table and "wing it" to get the cars down the track, but this would be a neat setup if you were so inclined.
BTW, I have a few videos of O gauge humping action from a few weeks ago at the GATS: http://www.boche.net/trains/GATS_Canturbury_2-15-04/13.mpg http://www.boche.net/trains/GATS_Canturbury_2-15-04/18.mpg Take a look if you like.
I'd guess that the largest problem in making an N scale hump yard work, might be car weights. MicroTrains cars and trucks roll well. But some cars are quite light. Such as their hoppers. Nice pun Doug! "...so inclined...." Boxcab E50
Doug, greetings Interesting idea.. you know a bar code printer and reader is getting to the dirt cheap stage now... Your ideas spring thoughts of a bar code under each piece of stock and a reader set between the rails on the downside of the ramp, auto switching the pointwork for classification. As to weights on cars.. one thing I am keen on, and have done so far, is to match the weights of all cars to the NMRA standards. Interestingly enough, this really helps as cars of different lengths appear to gain the same speed on my trial "hump". I have found so far that, yes I need slightly steeper than prototypical grades to get things going, but with a lead from the top of the hump at 10% for 1 foot and a run through two switches total, giving 4 tracks with each track being 3 feet long with a rise at the end of each classification track of 3% for 3 inches to act as a final brake, I can assemble trains quite happily without smashing things into each other to hard and overrunning the yard. Based on this, I thing the retarders may only need to be cosmetic in appearance. Interestingly though, this is perfect for single car classification.. if I run a double car into the yard, they tend to get some good speed up due to the double weight.. now this may need either a retarder of some sort.. again, brilliant idea with the plastic dental picks, or alternatively just accept the single car distribution. Interesting.. the brain is still working Nice videos by the way Regards
