DCC to Proto MPH

Very simple. HO is 1:87 scale, so one mile is 5280/87=60.7'. Therefore, 10 mph, for example, would be 10.1 ft/sec. The formula is speed*5280/scale/60 ft/sec, or for simplicity, you can get awfully close with mph = ft/sec in HO. Other scales would differ. O, for example is

1:48, so the formula is speed*5280/48/60 ft/sec. Unfortunately, mph = 1.833 ft/sec/in O. I forget the scales for S, N and Z, but the calculation would be the same.

Lessee, one scale mile is 60' (roughly). So one scale mile per hour is 60 feet per hour, or one foot per minute. That makes 10 smph equal to 10 feet per minute, right?

You might want to recheck your math, those damned decimal points can be visious. Also, there are 3600 seconds in an hour not 60. Hope this helps. Jerry

If you use 1 ft/sec you get awfully close to 60 mph. so 30 mph is about

2 seconds per foot. Never mind all the fancy calculations.

Dale.

Jim Sargent wrote:

I raised this question not long ago and someone gave me this website.

It has a handy calculator to figure out "scale speed". I was also presented with a huge amount of other theories from the group too, but the calculator was good enough for my needs.

There is a lot of other very useful info on that website too. After I got there and started reading, I almost forgot why I went there in the first place!

Good luck and get ready for the flood of info that you are probably about to receive!

Take the desired speed in miles per hour and divide by 4.95 to get HO scale inches per foot. For example, 10 miles per hour / 4.95 = 2.0 inches per foot.

Here are a few speeds and corresponding HO scale speeds:

1 mph = 0.2 in/sec 5 = 1.0 10 = 2.0 20 = 4.0 30 = 6.1 40 = 8.1 50 = 10 60 = 12 70 = 14 80 = 16 90 = 18 100 mph = 20 in/sec