Your Radius..

[jacon12]

Are most of the curves on your HO layout 24r? And does this mean that for a full 180 curve you have to have a min of 48 inches table top and a little more than that if you used easements. If I understand easements correctly they're a slighter section of curve, short section, that leads into a tighter curve.. i.e. use a short section of 22 r. before going into an 18 inch radius circle, and do the same coming out of the curve before connecting into a straight section. Is that about right? I'm thinking about a folded dogbone type layout here.
No, reading what I just wrote.. it will be 48 inches from center line to center line so you have to have at least 50-52 inches of table top to stay off the edge.
I know that you can do HO layouts using all 18 inch curves but then you'd be very limited in what you ran on the layout. It really gets space consuming in O scale where there is not a big selection made to run on 27 R. the tightest recommended now is 31r, and a lot of O modelers won't even lay track unless it's over 48 r on the curves. That's when you really need a 30x50 foot basement, at least. So, I guess my question is what you have and are you satisfied (I don't think we're ever satified til we get the real thing). And what is the real minimum radius a person shoud do ASSUMING you want to run the longer and bigger locos and cars?
Thanks,

[Anonymous]

There's a big discussion on this over in the General Discussion forum, and it seems most have 22" or less. I'll have mostly 20 - 22" on my under construction layout, with 24" in the extreme corners (it's U-shaped), and 18" where necessary. But I'm modeling the 50's, just about all 4-wheel truck diesels, so that'll be fine.

22 - 24" is usually the recommended minimum for big locos and cars, but some/many will run on tigher radius. They may have a lot of overhang, but if it the curve is judiciously hidden (like behind buildings or in a tunnel/mountain) it won't be noticable. You also have to watch coupling distance -- too close, and the cars could hit on the corners going around a tight curve.

[jacon12]

Thanks Joe. Is your layout essentially a folded dogbone, if that is the correct term?

[Anonymous]

Essentially -- The top loop is hidden in a mountain, and the bottom loop is in a staging area below the benchwork, with the curve downward under the upper loop. It's not a pure dogbone, since I have some sections that are single track, but for the most part its dual-tracked, foothills-to-mountain, and will have 4 or 5 staging tracks below, and a decent yard with 5 or 6 ladder tracks and maybe a turntable & roundhouse. Period is mid-late 50's, so though I have all diesel power now, I do plan on getting a steam engine or two.

I used 3rd PlanIt to design it, and have just started laying sub-roadbed/roadbed/track. The mainline is pretty much set, but the staging and yard areas will probably change as I see what kind of room I really have for them.[:)]

It's in a spare 91/2 x 11 foot room, of which I can use about 7' on one wall, 91/2' across the back, and 10' along the other wall. The last 3' of that section is built to fold down, so I can have access to a closet and the pull-down attic stairs in that corner. The fold down section will be one curve and the dead-ends of the yard tracks mostly. The isle in the middle will be about 21/2 feet wide., so you can see why I have to use some 18" radius curves to fit everything.

[jacon12]

Planit has been highly recommended to me before.
Thanks!

[ndbprr]

As one who has been in the hobby in HO for 50 years now I am concerned with the acceptance of less than 30" radius for full size cars. Back in the 60's when full length equipment started to become available 30" radius was the minimum reccomended and with good reason. It is big and need the room to avoid overhang and poor operating tendencies. Having built and dismantled several layouts due to moves I have decided that the one I will be starting as soon as the bank approves the house I am purchasing will have 48" radius curves as a mainline minimum. I would go 60" if I could. I realize not everyone has this luxury but the compromises in fidelity to get massive locos and cars around sunstandard curves they wouldn't be allowed on in real life is a little disconcerting to me at this point. My moral of this? Always go with as big a curve radius as you can even at the cost of something else.