[:)][:)]I am down sizing from a large layout with 48inch curves to a much smaller size. I am trying to find out the minimum radius for Rivarossi Mallet class
2-8-8-2 and also diesels such as Dash 9 and similar engines.
Rodney Gill
Melbourne Australia
What scale is it?
Rivarossi Mallet class 2-8-8-2
G Scale: ABSOLUTE MINIMUM OF 8 FOOT DIAMETER CURVE
HO Scale: Probobly around 22" Radius (recommended for best results)
O Scale: O-72
N Scale: Articulated to operate through 18" radius curves and #4 turnouts
Not sure about the steamer, but most big 6 axle diesels might work on as small as 18", but I wouldn’t go any smaller that 22" if I were you.
Your are looking at a MIN RADIUS of 24, they look like heck but work. 30" min is realy a better thought. The “Big Boy is MIN 32” per the Mfg, I TRIED 30" the Locomotive was fine the TENDER was the prblem, Centipede design.
The larger the less chance of binding and problems.
Thanks to all for your quick reply I did forget to metion scale was HO.
Thank All
Rodney Gill
Downunder
If it helps, I have an HO Rivarossi 4 6 6 4 Challenger that negociates 16" radii. Was designed for 18" minimum, but goes 16". Now, it don’t look worth snot doin it, but it does it.
I have a Rivarossi Y6b it will take an 18 inch radius but you can pull more cars on a 22 inch radius. My 6 axle diesels seem to be fussier about the smaller radii curves than the articulated steamers (plastic and brass), 10 coupled steam locos seem to be best at a minimum 0f 22 inches or bigger.
It’s nice to have choice.
22"-24" range.
If you had 48 inch curves *(Im so jealous LOL) you should plan on 32"
That way you can run anything you want. No problem eh?
I have 6 axel diesel’s running on 18" curves and some 22". I don’t plan to change it either. Some Loco’s out of the box work just fine as others don’t like Kato’s. So what I do is pull out my Dremmel (Every modeler should have one) and cut off the weights around the trucks to give it more play. I think every Kato loco should have this done as there is no room for the trucks to move.
My second opioion on what I think you should do is don’t use any set base curve track like 18,22 ect. My entire layout consist of Flex track. It’s simple too. Just curve a piece of flex track where you desire and test your 6 axel or steam loco on it before you permantley tack it down. A little common sense is used to know what’s too tight and what will work.
My board is only 4x10 and any loco would work. I may have to apply my first rule but with a Dremmel, it’s nothing
The Rivarossi 2-8-8-2 should make it around 18" curves fine. Most 6 axle diesels like DASH 9s and SDs can make it around 18" curves too. I have a Kato SD80MAC that’s a foot long and it makes it around my 18" curves without a problem.[:D][:D][:D]
If you must go lower than 18 make sure the train takes it slow and steady
Some three axle diesels will negotiate the 18" running without cars but?
In the absence of a Dash 9 modeler, I would e-mail the manufacturer.
If you ever decide to do passenger the Budds rrecommendation is 24".
What radius a particular product can negotiate varies from different manufaturer to manufacturer.
A ‘top of the line’ brass engine (expensive) will need near-prototype curves, wheras a Rivarossi or BLI will have made compromises to accomodate a larger less-discriminating market - example 56" wheels replacing 63".
MOST equipment made today is designed to work (stay on) 22"r curves. It’s not prototypical, but there a lot of HO buyer’s out there who’s layout’s are limited to 4 x 8 board’s, and for many maufacturer’s a $ale is a $ale is a $ale.
The pro’s and their club’s generally preferr 36" min.r for steam. Diesell’s don’t have side rod’s, and can operate better on the tighter curves. If you must downsize, i’d recommend 36"r for steam, and 28"r for Road Diesel’s .
It’s more than prototypical on a logging line. In fact, less than that is still prototypical.
Be glad that you said “most” 6 axle diesels “might” work. I can guarantee that my LL Proto 2000 E8 hates 18" curves. It won’t derail but you can really tell that the middle axles on each truck are binding in the flanges at that radius. That is why I have decided that my permanent layout (8 feet by 11 feet donut) will have 24" minimum, and I have found a couple of Ian Rice plans (Small, Smart, and Practical Layouts) that have 30" radius on the mainline. I would say that you need 22" in HO as a minimum on your mainline. Save the 18" radius for industrial spurs, etc.
I agree with the last poster. All I could get that was bigger than 18" when I needed them quickly were 22" in EZ-Track. The work just fine, but look terrible for a realistic scene. So, on my next go-around, I will use nothing less than 30" on the main, and feel that the 22" are ust about right for yards…24" would be better. If I get my way, though, I will use 36" on the main.