I just got my P2K Heritage 2-8-8-2 HO steam loco. It is absolutely beautifully detailed and runs (DC only) very smoothly. My question is: it has very slow top speed. Is this normal? I have a Spectrum 2-8–8-2 and it is also very slow on top speed. I have heard that they are drag freight engines and didn’ t run much more than 60mph. I timed both locos on a 3 foot section of track and both ran about 5-6 seconds. I have a speed table I got from one of the forums that says 3 feet in 6 seconds is around 67mph. Does this sound OK to you? Just looking for confirmation that they don’t run very fast.
Mallet’s were designed to pull heavy loads in almost inaccessible areas like mountainous areas.They were articulated with small drivers to handle very sharp curves and speed wasn’t a concern.They could barely reach 40 mph.if at all.
According to the book “N&W: Giant of Steam,” a Y-6b could make up to 50 mph although it did most of its work at lower speeds. They exerted a maximum of 5600 horsepower at 25 mph. The could maintain 5000 hp or more throughout the speed range 17 to 34 mph. Their maximum rated tractive effort was 152,206 lbs, but in operation were measured up to 160,000 lbs. Designed to be mountain climbers, they were extraordinarily capable locomotives.
I’ve got the Rio Grande Heritage 2-8-8-2, and yes, it has a very low top speed. But then you figure scale 57" drivers, and the prototype was a drag freight engine (Rio Grande used the mainly in helper service over Soldier Summit), so we’re not talking race-horse, here, LOL!
The loco has beautiful speed control–like yours, mine is strictly DC–and is a pretty decent hauler. I bought mine specifically for slow-speed heavy freight hauling, and it does a very credible job at it. IIRC, the top speed at 12 volts is about 50SMPH and that’s about as fast as I’d ever want to push it.
Simple articulateds like Challengers, Big Boys, Cab-Forwards and even Yellowstones could be pumped up to about 70mph if need be, but these lower-drivered compound Mallets were built for hauling, It was said of them that they’d haul anything you wanted to put behind them as long as you were in no hurry to get there, LOL!
It’s a beauty of a Mallet, IMO. I wouldn’t mind getting a couple more of them.
Thanks guys, just the kind of feedback I was looking for. I will haul accordingly! I plan to convert to DCC as soon as I decide what decoder to use. Have several for hard wire but may opt for a plugin.
At 50mph, N&W Y class locos were pushing their limit, both for track damage and damage to the engines. The culprit was dynamic augment. 58 inch drivers were too small to carry enough counterweight for any higher speed.
If your model was full size and ran at 67mph, the MOW supervisor and Road Foreman of Engines would be in a race to run you down and issue you an unpaid vacation.
Chuck (Modeling Central Japan in September, 1964 - steam speed limit, 70kph)
Sounds like you got a hold of an N scale speed table.
In HO, a scale mile is just about 60 actual feet. 60MPH is one mile per minute. So an HO mile in one minute is the same as 1ft/sec. Or 3 seconds for 3 feet. 6 seconds for 3 feet is 30 scale MPH in HO.
A realistic drag freight speed in the early 1920s was about 10MPH upgrade, and maybe 20-30 on straight and level or downgrade. Let’s use 20 MPH as our desired speed. That’s 3 seconds per foot, or two 40ft HO cars every 3 seconds. So a 20 car train (40ft cars) will take over 33 seconds to pass a switch stand. Pretty realistic, but probably boring to some. Which is why not so many operate at realistic scale speeds.
Bob, one additional response re speed: The formula for calculating scale speed is:
(D (in real feet)/t (seconds) ) X 3600 / 5280 x scale ratio (160 for N, 87.1 for HO, 48 for O, etc.)
Where D is the distance covered.
Thus, in HO, 3 feet in 5-6 seconds is 29.69 - 35.63 sMPH. To do 67 sMPH, you engines would have to cover the 3 feet in about 2.7 seconds. Way too fast!
I have a spreadsheet that I put together using that formula which I have found to be quite useful. I can plug in any distance, and the scale (HO, N, S, O, TT, Z, and Q - 1:45) , and look up the time. It is just as accurate as your thumb on a stopwatch. If you want it, just drop me a message (“Conversations” in the right-hand column) and I’ll email it to you.
Alfred W. Bruce in “The Steam Locomotive in America” (1952), notes that the rule of thumb applied up to about 1930, although exceeded many times; the modern high-speed engine in passenger service often exceeded by 25% or more in regular service; maximum horsepower outputs generally reached about 300 rpm for modern heavy freight engines and 360 rpm for modern passenger engines; the difference due mainly to variations in counterbalance conditions and general design characteristics. He notes that driving wheel diameter speed is 336 rpm on all engines (at that rpm the speed in miles per hour equals the driving wheel diameter in inches).
To the amusement of other club members the Grizzly Northern’s drag freights, usually doubled headed with a 2-10-2 and 2-6-6-2, and with a rear end 2-6-6-2 pusher ahead of the caboose, trundle along like elephants at no more than 20 scale mph on the flatlands of the club, well below the rule of thumb maximum horsepower speeds (57 in. and 56 in. diameter drivers respectively). Fuel and water consumption rates on these pre-modern beasts rise dramatically when pushed to maximum horsepower.
