how about for this one?..http://www.walthers.com/exec/productinfo/635-HR2470
i don`t see this info listed on walthers…at bachman trains online i seen 3, outta about 15 i clicked on that listed the min. track angle…
How do i know which trains will for a given track angle? is there a “FAQ” about this i`m missing?
thanks
Gidday, I presume you’re asking about the minimum radius curves it will handle. If you look here… http://www.walthers.com/exec/productinfo/635-HR2469… it says 16" (40 cm) which I think is totally ludicirous, especially when this site http://www.modeltrainstuff.com/Rivarossi-HO-4-8-8-4-Big-Boy-UP-w-DCC-Sound-p/riv-hr2358.htm refers to a recommended minimum radius of 22" which I think is far more believable. I would not consider trying one on any less than the 22" radius and even the overhang would look some what ridiculous.
Hope this helps,
Cheers, the Bear.
Well, it is articulated, but with two sets of 8 driver wheels, plus the 5 axle tender, it will not only look funny on tighter radii, it will derail. I have 32" radius curves on my layout, and I wouldn’t even consider running such a beast. If you don’t have minimum radius curves of 36" or greater, you are going to be disappointed as well as poorer.
Rich
That loco you referred to is a Union Pacific Big Boy 4-8-8-4, considered the largest or one of the largest ever made.
I would not consider running one of these on anything less than 36 inch radius HO track.
Of course these are pretty expensive, and certainly not something for the newbie to the hobby.
I found this amusing, read what it states, as far as minimum radius curves, go.
http://www.walthers.com/exec/productinfo/635-HR2469
Cheers, [D]
Frank
Frank, Ja Bear beat you to it with that link.
Rich
[(-D] [(-D] You fell, into the trap!
Cheers, Dear Buddy!
Frank
16" curves!!! That I would have to see to believe.
Now a 16" curve in N is a rather nice curve but,a very tight curve in HO.
A engine that large and its nothing less then 36" minimum and in this case the larger the better.
AArgh!!! I thought i was linking to a Climax, geared steamer,http://www.walthers.com/exec/productinfo/160-82906 oh well, the big boy i linked brought up some good discussion for me…is the 16" data a missprint? is it N scale data? how can there be such a huge difference from what you guys are saying and the listed info? (for the record, i beleive you guys)
thanks for all the reply`s
also, how to edit my original post…can`t find edit button…
Well … back when the Rivarossi steam locomotives were imported by AHM (and yes I am aware the tooling has changed since then, and the drivers were undersized due to the huge flanges) the N&W Y6b that I owned was rated at 18" radius curves but I know for a fact it could run on 15 inch radius curves. Rivarossi had engineered the loco with extraordinary side play in all drivers, with valve gear and side rods flexible enough to match.
The Big Boy has larger drivers and even more crucially, a tender with a huge rigid wheelbase. The 1960s Rivarossi from AHM actually hinged the rear wheels on the tender - I do not know if the current version still does that. The Model Railroader review in the July 1967 issue said the engine would traverse a 22 inch radius curve, but there is no mention if they even tried it on sharper curves. Based on the remarkable performance of the Y6b it might just be that the HO Big Boy can take a 16" radius curve. That 1967 review mentions that the model had 61" drivers versus the prototype’s 68" drivers.
At first I wondered if Walthers had confused the mininum radius of the Rivarossi Big Boy in N scale that Con-Cor used to offer, but the review of the N scale engine in August 1980 MR says the minimum radius is 9".
Dave Nelson
The NMRA Recomended Practice RP-11 gives guidelines. However because of the way they are constructed, it is sometimes be possible to run a specific model on a sharper curve than specified.
https://www.nmra.org/standards
The RP’s can answer many questions.
I know that to be true. I changed out a motor on a Rivarossi Y6B. It would take curvs as tight as 15". Didn’t like it but it would do it. As far as the Rivarossi Big Boy goes I’ve seen one go through an 18" radius curve. Slowly but it did it so there shouldn’t be any reason it couldn’t take 20" curves. As for the new ones I don’t they could even look at a 20" curve.
The AHM/Rivarossi Y6B came in a set with 18" curves and looked terrible as it rounded those curves but,round it she did.
The AHM/Rivarossi Big Boy came in a set as well.
From Walthers:
“As the largest steam locomotive ever built, the 4-8-8-4 makes an impressive addition to any steam- or transition-era layout. This detailed model wears black and silver colors and features operating knuckle couplers and RP25 wheelsets for operation on code 70 or larger rail. Requires 16" (40cm) minimum radius curves.”
That has to be a misprint, thats all I can say.
WEEEELLL ! if you want to be correct, the big boy’s sharpest curve could negotiate was 20 degrees, In HO scale that is a 40 inch radius curve. Thats what it said on the official Big Boy site.
Thats rather irrelevant as model trains regularly go around curves that are much tighter when scaled down to HO.
Moreover the prototype articulateds had the rear engine rigidly attached to the boiler and only the front engine could swivel or pivot – Rivarossi cleverly found a way to make both engines pivot and that is why they can take such sharp curves, in addition to the sideplay of the drivers and other such compromises.
Dave Nelson
Just out of curiosity, what is the total length of that locomotive, from the front pilot to the rear of the tender?
Rich
If memory serves a Big Boy measured 133 feet coupler to coupler, a major nitpick I have is the continued application of aluminum paint on the smokebox and firebox, UP never used aluminum in these areas when they were in operation, same for the FEF’s, Tenshodo also got this wrong 40+ years ago, all 4 of mine have the silver treatment as well!!
Dave
RG 5761:
And, and, and that is why a passenger train going around a curve on an HO layout looks so strange, just because an engine CAN go around a tight curve should not be criteria for all curves, the larger the curve the better in many ways.