MTH HO K4 - Mixed feelings?

Folks:
It's unfair of me to say this. I don't own it, nor will I, given its $400 list price. Still, based only on the review in the July MR
my feelings are indeed 'mixed', to say the least. And you know, most of these aren't unique problems, just rather extreme examples of what I consider common features of modern HO steam.
1. What happened with its speed? Indeed, what happened with the 12v HO standard? MTH says it runs 70 @ 12v, MR says 13 SMPH...what happened? Anybody else there got this machine yet? Did somebody calculate wrong? Not so much overthinking here, really, but perhaps a little too much voltage drop through diodes? Too much electronic complication?
2. Power pickup through tender, automagically switching to engine when required? Why not just pick up through the lokey all the time and eliminate the committee of vigilance? There's a triumph of overthinking for you.
3. 10 car pulling capacity? Seems a little low on the level. My MDC 2-6-0 can probably do better than that. Traction tires really aren't an elegant solution...I hope there's a way to add weight.
4. Puffing smoke...nice for a show, and the puffing feature is ingenious, but you know, the Reynolds number just isn't right on any smoke unit I've ever seen. Perhaps if it were ejected at 87 times the real velocity? :) Perhaps they could use hydrogen-based smoke ? :D
5. Yellow LED -- almost rather have a jewel. They just don't look like a headlight. Headlights look yellowish but not like an LED...
That's all. I'm not saying it's a bad engine, just that I'd like to see more opinions. Care to comment?
Cordially yours: Gerard P.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In addition to the things you mentioned something does not look quite right about it. Its a really nice looking model but the space above the trailing truck looks very empty. In the pictures I've seen of K4's it looks like the frame or something takes up more space under there. Can't say I'm right for sure, maybe is just the pictures don't show the space well. I have not seen a straight on side view of other K4s by BLI or Bachmann so I can compare it to those either. I don't model the PRR but K4s are beautiful locomotives. Bruce
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bruce Favinger wrote:
> In addition to the things you mentioned something does not look quite > right about it. Its a really nice looking model but the space above > the trailing truck looks very empty. In the pictures I've seen of > K4's it looks like the frame or something takes up more space under > there. Can't say I'm right for sure...
Bruce, you are correct, the frame and ashpan occupy that space on a real K-4.
Mark.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks Mark. Maybe they left the frame and ash pan off allowing the truck to have enough swing so the locomotive could handle the tight curves so many people have to live with. Do you know if BLI or Bachmann managed to represent the frame and ash pan over the truck? Bruce

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

represent the frame and ash pan over the truck?M There are a number of pictures on the BLI site. While the angle of the shot doesn't really tell to me there is not much daylight under there. See this picture;
http://www.broadway-limitedwest.com/images/prrk4/54183quarter.jpg
It seems all the latest steam engine have detail in that area that should be improved. As was guessed the reason is sharp curves. I personally would buy the BLI simple because of the havoc MTH caused the sound decoder industry.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Jon Miller wrote:
>> Do you know if BLI or Bachmann managed to > represent the frame and ash pan over the truck?
> There are a number of pictures on the BLI site. While the angle of > the shot doesn't really tell to me there is not much daylight under > there. See this picture; >
http://www.broadway-limitedwest.com/images/prrk4/54183quarter.jpg
> > It seems all the latest steam engine have detail in that area that > should be improved. As was guessed the reason is sharp curves. I > personally would buy the BLI simple because of the havoc MTH caused > the sound decoder industry.
Jon, nice looking model! If I was ever in the market for a K-4, that's the one I'd get.
Cheers,
Mark.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

to
BTW, a simple fix for that is to glue or somehow attach some black plastic sheet as a filler or view block dead center under the cab. I did this with the Athearn Genesis 4-6-2, and I was pleased with the results. It's not perfect, but it fills that massive void under the firebox that just shouldn't be there.
Paul A. Cutler III ************* Weather Or No Go New Haven *************
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Bruce Favinger wrote:
> Thanks Mark. Maybe they left the frame and ash pan off allowing the > truck to have enough swing so the locomotive could handle the tight > curves so many people have to live with. Do you know if BLI or > Bachmann managed to represent the frame and ash pan over the truck? > Bruce
Dunno, Bruce, I've not seen either model. But I reckon you'd be right about why there is so much daylight under there.
Cheers,
Mark.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gannon.edu wrote: [...]

[...]
Um, from my study of photos and articles, I'd say that 10 heavyweight cars was close to the limit for the real K4. It could haul more if it had to, maybe, but it no doubt struggled. The K4 was built for speed, not drag loads.
Then there is the question of protoypical train lengths. In HO, a K4 plus 10 cars would be 9 to 10 ft long - a pretty good size in that scale. In real life, it would be about 900ft long - the length of three football fields! Too long: railroad companies didn't want their customers to have to walk too far. Keep in mind that these trains originated and terminated in stub terminals, and were loaded from the end. The NYC's 20th Century was assigned five to seven cars through most of its history, if photos show typical consists. The PRR's Broadway Limited (hauled by K4s in its heyday) appears to have been the same length. During WW2, trains were of course much longer - and slower, too.
Many model railroaders seem to have an exaggerated idea of how much a steam loco could pull. OTOH, hard data on actual train consists is surprisingly hard to find. I have a Classic Trains article on three name trains: nowhere in it is there any data on actual consists.
BTW, 10 cars would be about the limit for a 2-6-0 on a typically hilly branchline.
HTH
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Good morning Wolf;
wrote:

Is there a way to calculate required tractive effort? For example, how much TE is necessary to pull a give weight up a 3% grade? Passenger trains would normally be shorter in length to minimize weight as freight can wait whereas people can get owly being delayed even a few minutes.
Cheers, John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
John:
Sure: the Davis formula, valid for level track, and working best for speeds to about 5 to 40 mph, and good enough for a general idea at higher ones:
R=1.3W + 29n + 0.045WV + 0.0005AV^2
where R is the train resistance in pounds per car, W is the weight per car in tons, V is the speed in miles per hour, n is the total number of axles, A is the cross sectional area in square feet, and V^2 represents the square of the speed.
For grade resistance, take the Davis resistance and add 20 lb resistance per ton of car weight per grade percentage point. Curve resistance is roughly equal to an 0.04% grade per degree of curvature.
These last two figures were found here: http://www.arema.org/eseries/scriptcontent/custom/e_arema/Practical_Guide/PGChapter2.pdf
I also found here that the starting resistance (above freezing) of a solid-bearing equipped train is about 25 lb/ton. From this, I find that a K4, with TE 44 000 pounds, could start 44 000 / 25, or 1760 tons ... 20 heavyweight cars, a very considerable train. In winter, it could start 15.
This would imply that the MTH K4 has about half the TE that it should...and oddly enough, the review shows its TE as being about half the average for HO locos! Interesting that they should emulate the prototype in this way...
Cordially yours: Gerard P.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I wrote the Davis formula:

Using this (somewhat inaccurately) with: Speed 70 MPH Weight 85 tons per HW car Axles, 6 per HW car Cross-section area about 200 sq ft per HW car
I get:
R = 1.3*85 + 29*6 +.045*85*70 + .0005*200*70^2 R = 111 + 174 + 268 + 490 = 1043 pounds per car. Grades: Add 20 lb / ton / percentage
1% grade adds 20*8500 pounds...total R, 2743 lb/car
Using a boiler horsepower of 3000 (a bit high? The M1 had 4000, but I can't seem to find K4 HP figures just now) for the K4, at 70 MPH:
TE = (3000 HP * 550 (ft*lb)/(s*HP)) /(70 MPH * 1.47 (ft/s)/MPH) TE = 16000 lb
Cars on level track = 16000/1100 = 14 on 1% grade = 16000/2800 = 6
Ah...I just noticed that Bowser had some figures on their site...apparently the K4 was designed to pull 11 cars when hand-fired, and uprated to 16 cars with a stoker, at an average speed of 65-75 MPH...not too far off the calculations, really. Now I feel like a chump for going through them all. :)
http://www.bowser-trains.com/holocos/k4/k4.htm
Cordially yours: Gerard P.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
My questions is, "Why *another* K4?"
Its like another F7A.
-- Cheers
Roger T.
Home of the Great Eastern Railway http://www.highspeedplus.com/~rogertra /
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Roger T. wrote:

Rog:
To be fair it's been like this since early in the hobby. I have a magazine from 1935 where letter writers were griping about the ubiquity of K4 Pacifics and NYC J3 Hudsons.
Cordially yours: Gerard P.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Because eveyone who models PRR steam can always use another K4. Bruce

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 22 Jun 2006 19:28:45 GMT, Bruce Favinger wrote:

Oh. I thought it was some folks liked that hunchback Belpaire look.
--
Steve

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve Caple wrote:

Yeah, me. I love it. Probably because the God's Wonderful Railway adopted the Belpaire firebox.
But that doesn't mean I'll buy another K4. One is enough. I don't model the PRR, so the K4 has to be a, er, um, guest, maybe.
HTH
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Steve Caple wrote:
> On Thu, 22 Jun 2006 19:28:45 GMT, Bruce Favinger wrote: > >> Because eveyone who models PRR steam can always use another K4. >> Bruce > > Oh. I thought it was some folks liked that hunchback Belpaire look.
Well, I certainly do. But then I grew up with a railway that used Belpaire fireboxes almost exclusively!
Cheers,
Mark.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
So if the model could get 2 or 3 cars up a 3% grade it's doing better than the prototype. Why do modelers have such a tough time understanding what an engine can pull.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"Jon Miller"

We need models that can pull better than the prototype because our models have to haul trains that are generally steeper than those commonly (Commonly, yes commonly) seen on the prototype. A 1% or 2% grade is very common on a model railway but they were considered very steep on the prototype. Therefore, our models need to pull up a 1% or 2% grade than the prototype could pull up a 0.5% or 0.25% or less grade.
One more time, notice I used the "commonly"? We don't need people now pointing out that so and so railway pulled trains up two, three or even four percent grades. That's NOT common. The vast majority of grades were and are less than 1%, a "gentle" grade for modellers.
-- Cheers
Roger T.
Home of the Great Eastern Railway http://www.highspeedplus.com/~rogertra /
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.