how fast does it really go?

[jward]

ever wonder just how fast your locomotives are actually moving, in scale speed? here is an easy way to calculate scale speed in HO.

1 scale mile in HO is approximately 60 feet. 1/10 of a mile is 6 feet, or two sections of flex track. time your locomotive, running full throttle, over two sections of flex track with a stop watch. the following are approximate speeds for various times over a 6 foot section:

10 mph, 36 seconds
20 mph, 18 seconds
30 mph, 12 seconds
40 mph,  9 seconds
50 mph, 7.2 seconds
60 mph,  6 seconds
70 mph,  5.14 seconds
80 mph, 4.5 seconds
90 mph, 4 seconds
100 mph, 3.6 seconds
110 mph, 3.27 seconds
120 mph, 3 seconds
130 mph, 2.77 seconds
140 mph, 2.57 seconds
150 mph, 2.4 seconds

anything faster than that, you should really consider taking up slot cars.....

[Michigan Railfan]

Thanks for posting that. I just used it today to calculate some speeds for a video I'm making of where a CSX AC4400 hit a boxcar on a switch. I smashed the boxcar so it looked real. Now before everyone goes and says i wasted money, it was just a cheap Life Like model. So, would 10 seconds be equal to about 35 mph? And would exactly 5 seconds be around 65 mph? Just curious because those are times I got. Thanks again. Really helped me not do math 

[Doneldon]

Blink-

I estimate that 10 seconds would be just about 36 mph and 5 seconds would be 72 mph.  I hope this helps.
                                                                                       -- D

[Michigan Railfan]

Thanks Doneldon. I guess I will have it 35 and 65. 35 because, well it's only one number away, and 65 because 72 would be a little high for a frieght train. Thanks.

[Michigan Railfan]

Thanks for the link Hunt. The equation could be helpful.

[jward]

yes, hunt.
thanks for posting the formula. i've been trying to come up with a simple way of explaining it, but you beat me to it.

[railsider]

Just measure off a section on your home layout, or locate landmarks that you can use, and use that stretch of track. Clearly, if you can run a 60-foot section, you can measure more accurately by using 10 times the figures given....
i.e., 360 seconds (6 minutes) over 60 feet = 10 mph; 36 seconds = 100 mph, etc.

Railsider

[richg]

I found the below link sometime ago in A Google search. Never tell what you can find when searching the 'Net.

http://home.cogeco.ca/~trains/rroperat.htm

Now I use a stop watch with a known section of track. I use 60.6 feet for a HO scale mile. 5280 feet divided by 87.
After a while it is easy to calculate the speed of the loco.

Rich

[Jim Banner]

If you reduce Rich's 60.6 feet to 60 feet (an error of only 1%) then that mile a minute reduces to one foot per second.

Now if you run 40 foot box cars, you probably know that they are quite close to 6 inches long.  So two of them are a foot.  So if two of them go by every second, the train is moving at 60 miles per hour in scale.

You might find it easier to measure the time for just one car.  Then if it takes 1 second for a 40 foot car to pass a given point, the speed is 30 miles per hour.  If it takes 2 seconds, then the speed is 15 miles per hour and so forth.  If they are 50 foot cars, count off the seconds a little slower.

Scale this back up to the real world and it still works.  Next time you see some switching action, count the seconds for a car to pass and see if the engineer is really slowing down to 3 miles per hour (10 seconds for a car to pass you) when he couples on or if he is cheating a bit.

Jim

[jward]

60mph is 88 ft per second. or, one auto rack per second.

[NMWTRR]

Great info and easy to use!   

Thanks