Dual track N scale radius in a 3 foot wide area?

[CTConrail]

Hey guys I am new to the forum but not model railroding however I have yet to build my dream N scale layout. I am trying to design it now so when I move and install my train building (16x12 shed) I can get right to work.  I have my layout benchwork in sort of a capital "E" shape with each section measuring 3 feet wide. My layout will be set in the 90s-early 2000s so I will have container trains, 89' flat cars etc.  My question is is 3 feet a wide enough area to have dual track radiuses that will run 89 foot flat cars without looking unrealistic or toyish or will 2 trains passing eachother with 89 foot flat cars interfere with eachother on the turns? What size radius will work good for my situation or will I be ok with my space constraints and the type of rolling stock I plan to use?  Thanks guys!

[cuyama]

Welcome to the forum. Note that your first few posts will be delayed by moderation, so stick with us.

Here's a general discussion of radius versus diameter.

Here's a general rule-of-thumb for radius versus rolling stock length

Here's the NMRA recommendation for track-center-to-track-center spacing for various scales and equipment types.

And most folks want to allow at least 2-3" between the track and the benchwork edge.

One interpretation from all of this would be that it’s going to be pretty tight for long cars on your proposed double-tracked peninsula. Once you allow a bit of room for safety between the track and the benchwork edge, you have only about 30” for track. If you make the outside curve 15” (centerline) radius and the inner curve about 13 5/8”, that puts the inner curve at almost 2 times the rolling stock length. 

This is just below the rule-of-thumb minimum, but most N scale equipment is engineered to track on tighter curves, so you might be OK. But it will look toyish, to use your words. Mocking it up and testing it would be a great thing to do, both to be sure that there is no sideswipe and to see how it looks to your eye.

But a different (and better) approach would be to allow the benchwork edge to curve. Benchwork doesn’t have to be all straight edges, so widening the benchwork a bit at the broadest part of the curve would help a lot by allowing you to increase the radius. 

Good luck with your layout.

Byron

[CTConrail]

Thanks for the detailed response.  I am using xtrack to design by this and I kind of played around with building the peninsula out around the curve to compensate and give me a little more space. I measure about 40 inches from inner track to inner track now so that would be around a 20" radius give or take if I do it this way correct? That I would assume should put me in a good place as far as long cars looking more realistic. But definitely a good idea to kind of mock things up first to see where I stand and make any changes necessary.

[PED]

Grab some stock curve pieces (any brand) and experment with different radius and car length. I have a N scale layout built with Kato Unitrack as well as a big fleet of 89' bi-level auto racks. All my mainline curves curves are 481mm (18.9") or greator in single track and 718mm (28.2") in double track areas with 2.1" seperation in curves (stock Kato straight double track seperation is 33mm (1.3") which is a bit wider than NMRA standards. No problems with 89' cars hitting each other. All my 89' cars started life with talgo couplers but were converted to MT body mount to improve their abilty to back up through a turnout. No problems with either style coupler.

However, it does not sound like you have the space to use those size curves and track spacing. Two suggestions

1) Decide what is more important - tighter curver or 89' cars. Technically you can run both but you may not like the appearance. You may need to rework your design to allow for larger curves.

2) My facia board extend to about 1.5" above the track level. That allows me to run track closer to the edge with less risk of trains hitting the floor. You might try that in your design.

[ROBERT PETRICK]

Hey CTC-

Welcome to the forum. Double welcome for being an N-scaler. Always glad to see more of us.

Your post has two aspects.

The first being how tight a radius can your equipment physically negotiate. Kato makes UniTrack with radiuses as small as 9-3/4" and they produce very accurate rolling stock in the lengths you describe that can consistently make those turns. So, the dimensions Cuyama provided should be generous enough. I specifically agree with his 2- or 3-inch outside buffer to benchwork edge. I know many operators who have their own overhang to consider.

Related is the question regarding two 89-footers passing on the curve (either the same direction or opposite directions) and not scraping each other. This relates to radius and track center-to-center spacing. Again, Cuyama's 1-3/8" should work fine on the curves and more than enough on the straights.

Second, regarding appearance. Sometimes there is just no getting away from the roundy-roundy business. The easiest is to just live with it and embrace the suck. But with a little forethought and effort you can disguise and minimalize the toy like appearance. I went The Full Monty and put almost an entire 180-degree curve in a tunnel. You don't need to be so drastic. A short tunnel here and a short tunnel there with a long(ish) sweep of curve in between makes a big difference, perception wise. And a tunnel doesn't have to be an actual tunnel. A clump of trees on one side of the track and a big rock on the other might suffice. A building or a pipe rack or even a skeleton gantry crane could do wonders. The idea is to either distract the spectator or outright block his view entirely. The view block doesn't have to be on or adjacent to the offensive curve. A judiciously placed obstacle way on the edge of the other side of the peninsula might restrict the viewer from getting his nose (or his eyeballs) into a position to observe the offending overhang.

And a quick final thought: inside overhangs are uglier than outside overhangs. So, right off the bat half of your problems are gone.

Good luck.

Robert 

[rrinker]

 And to expand upon Byron's reply, if you also make the along the walls part of the benchwork narrower in the area where the penninsula widens, you can maintain your aisle width even though the widest part of the penninsula is now more than 3' wide. Mostly just means you can't have the middle of a large yard directly across from the widest part of the penninsula loop. Even a foot wide is decent for scenes of the train passing through the countryside, and if you were using nominally 2 foot wide sections, narrowing the areas alongside the penninsula to 1 foot each gains you 2 feet for the penninsula without any change in aisle widths - so you could have 5 feet to work with insteas of 3, and 5 feet is definitely enough space for fairly generous curves in N scale, even allowing decent space between the track and the edge of the abyss. 5 feet of width, or just under, would easily accommodate 24" and 22" radius curves with plenty of outside clearance - and such curves are quite generous for N scale and even the longer cars should look OK there.

                                    --Randy

 

[CTConrail]

Thanks for everyone's responses and feedback. I have started redesigning my benchwork to make the 2 outer peninsulas wides to facilitate wider turns but I will also use other described methods to disguise the overhang. One side will have a helix to level 2 that wont be visible (well not fully visible) so that will be one I don't have to worry about. If I had screenshots uploaded somewhere I would attach pictures. So at the helix and the other curves the benchwork gets wider which will allow for an inside track radius of 20" on all my turns so the outter track is even wider. I would assume that 20" would be pretty good looks wise?

[cuyama]

rrinker

if you also make the along the walls part of the benchwork narrower in the area where the penninsula widens, you can maintain your aisle width even though the widest part of the penninsula is now more than 3' wide.

+1