Am looking for a simple formula for determining HO guage scale speed - SIMPLE is the operative word. I used to have access/use of this formula back in the 80s, but alas, memory fails me. Any help or tips would be appreciated. Thanx,
G’ man
See description and table 2 here: http://www.awrr.com/scalecharts.html
Easy rule of thumb:
Count how many seconds it takes a 40ft car to pass a fixed point - sign, tree, switch stand, etc.
1 sec => 30 MPH
2 sec => 15 MPH
3 sec => 10 MPH
5 sec => 6 MPH
6 sec => 5 MPH (switching speed)
FWIW, the formula is a good approximation for all scales, including the prototype. If you want faster speeds, use an 80ft car (or 2 40ft cars) and double the speeds for the same amount of seconds.
Fred W
Excel
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Calculator: http://www.mcr5.org/NMRA/articals/speed.htm
Enjoy![:D]
That’s the same one I use. Easy to use.
Or you can use one of these great devices like we did at the local hobby shop / club
http://www.youtube.com/watch?v=6p9xhzdV8_A&list=UU2p1cqCGy-W5bPsoinOHZmA&index=7&feature=plcp
G’man,
I created an Excel spreadsheet for a 3-foot section of track. I time the locomotive between A and B then apply the following basic formula, which is already calculated up on a sheet of paper in 1-sec. intervals between 3 and 30 seconds:
[Feet/sec.] x 3,600 (sec. in a hr.) ÷ 5,280 (feet in a mi.) x [scale] = sMPH
So, for example: If it takes my HO locomotive 3 seconds to travel 3 feet, I would get the following answer:
3 feet/3 sec. = 1 feet/sec. x 3,600 ÷ 5,280 x 87.1 = 59.39 sMPH
If it takes my HO locomotive 12 seconds to travel 3 feet, I would get the following answer:
3 feet/12 sec. = 0.25 feet/sec. x 3,600 ÷ 5,280 x 87.1 = 14.85 sMPH
G’man, I don’t know if the above fits in the realm of “simple” or not - but it works well for me. Having the calculations already written out in 1-sec. intervals means that I can calculate sMPH with just a quick glance at the sheet.
And, if you want to calculate slower speeds: Reduce your A-B distance from 3 feet to 1 foot - or even 0.25 foot (3") - and apply the same formula.
Tom
Wow, Simon!..332 sMPH! Was that for a Guinness World Record? [:O]
Tom
Gidday, My idea of simple. Ashamed to say not sure what magazine this came from to give due credit too.
Cheers, the Bear
Simplest formula is Speed = Distance / Time.
In order to get an answer in scale miles per hour, convert the distance measured into scale miles, and the time measured into hours.
I use one lap around my mainline as the distance, which gives me a time of many seconds, easy to measure with a hand held stop watch.
Had to be able to handle the old Athearn rubber band drive Hustler…
Quick and dirty - in HO, 1 foot per second = 60 scale MPH within acceptable speedometer error.
Chuck (Modeling Central Japan in September, 1964 - maximum speed 70 scale KPH)
LION runs subway trains. Train is six (50’) cars or 300 feet. So the conversion to HO is already done.
LION times the front of the train to the back of the train with a stop watch.
So now him knows 300’ / time. But the beauty of it is that it works in full scale too. Time the passing of six coal cars and I know how fast the train is running. LION knows how long NYCT cars are, and thus knows how fast they are going.
Attached is the timetable that I made, it runs on a base 300’ train.
So it seems that the LIONs trains are running at 45 mph which is somewhat faster than NYCT which averages about 32 mph.
A question I have often pondered, attending many train shows there seems to be some mentality to see just how slow people can run trains, overhearing attendees at the shows comment why are the trains going so slow, even from a childs point of view they comment on the speed, I know I don’t want trains hurtling around at 200 mph, but try standing a safe distance from an actual freight train and compare its speed to a model train micro-creeping along a track. A nice comfortable realistic looking speed of a train actually adds to the realism. I hope the ultimate goal is not to see any visible movement in achieving slow running trains.
Think of a train passing a grade crossing.
Now, think of yourself at the wheel of the second car in the waiting line. Your sight distance to the train is about 40 feet - or less than six inches in HO scale.
Typical layout-viewing distance is a lot longer - and the train looks correspondingly slower. Think watching from the roof of a building a football field or more from the right-of-way.
As for what I do I will be the first to grant that a train running 70 KPH is NOT flying, in any scale. OTOH, the prototype was running down the side of a canyon on a track that was designed using snake for a straightedge. One curve had (and probably still has) a prominent 25 KPH speed limit sign. (Failure to observe a 15 MPH speed limit dumped 611 into the Tug River - and the repair led directly to her survival.)
The opposite effect is the reason I have no plans to include a Shinkansen route in my modeling. The bullet-nose would cover about a yard a second - and, from across the room, still look comparatively slow.
Chuck (Modeling Central Japan in September, 1964)
Yes, I’ve heard that comment many times at our club open houses. I think I’ve come to the conclusion that they have no concept of scale speed. They are used to seeing their Lionel Louie trainset or their slot car vehicles roaring around at full throttle.
Having done some speed matching of locos for a friend, I’ve found that out of the box Atlas locos seem to have a top speed of 80 to 90 smph. I’ve seen some Athearn blue-box locos with a top speed of 110+ smph. If one does some speed limiting and speed matching, and sets the top speed to some reasonable train layout top speed, say 60 smph, that looks very slow by comparison.
Now if you’re speaking of the 3 tie per minute slow speed, that’s a train on another platform.
Okay… A “shout out”’ and thanks for the many responses to my earlier inquiry re HO scale speed. Thanks to “JaBear”, New Zealand; tstage, NE Ohio… Thanks for the tip re www.mcr5.org/NMRA etc. Each tip was immediately applicable - AND - easy. Thanks,
G’ man
[quote user=“tomikawaTT”]
tatans:
A question I have often pondered, attending many train shows there seems to be some mentality to see just how slow people can run trains, overhearing attendees at the shows comment why are the trains going so slow, even from a childs point of view they comment on the speed, I know I don’t want trains hurtling around at 200 mph, but try standing a safe distance from an actual freight train and compare its speed to a model train micro-creeping along a track. A nice comfortable realistic looking speed of a train actually adds to the realism. I hope the ultimate goal is not to see any visible movement in achieving slow running trains.
Think of a train passing a grade crossing.
Now, think of yourself at the wheel of the second car in the waiting line. Your sight distance to the train is about 40 feet - or less than six inches in HO scale.
Typical layout-viewing distance is a lot longer - and the train looks correspondingly slower. Think watching from the roof of a building a football field or more from the right-of-way.
As for what I do I will be the first to grant that a train running 70 KPH is NOT flying, in any scale. OTOH, the prototype was running down the side of a canyon on a track that was designed using snake for a straightedge. One curve had (and probably still has) a prominent 25 KPH speed limit sign. (Failure to observe a 15 MPH speed limit dumped 611 into the Tug River - and the repair led directly to her survival.)
The opposite effect is the reason I have no plans to include a Shinkansen route in my modeling. The bullet-nose would cover about a yard a second - and, from across the room, still look comparatively slow.
Chuck (Modeling Cen
I keep variations on these formulas next to my layout for use during OP sessions. We have a couple of different timing spots.
I have been looking for an HO speedometer to put under the track with sensors and readout. Does anyone know of one? If not, I guess I’ll have to build one.
Richard
Well, there was this one, which I have and works well: http://www.trainspeed.com/TrainSpeed1.htm. Unfortunately TDP has exited this business. You may still find one out there if you do a search.
I have been told that Greenway Products has acquired this design, but that is rumor which I cannot confirm.
Regards
EDIT: I did search Greenway’s website and it does appear, out of stock: http://www.greenwayproducts.com/storeroom/Electronics/trainSpeed.html