Good morning, I am thinking about building an N scale layout. I do have an HO scale at the time, although I do not plan to disamble the HO scale but rather build an N scale on another layout. Some time ago my dad was going to build an N scale and bought a LL steam set and about 30 pieces of 9 3/4’’ radius track and 15 straight pieces.He never as much as ever started any of the layout building since the loco did not run when he got it. The train as of now does not run, I will want to get some better quality locos and rolling stock. The track is all NS in either Bauchmann or Atlas.
Now for the question, I know that some of the larger trains and rolling stock in HO wil not run on 18’’ curves, what do I need to watch for in building an N scale? What is the minimum radius curves I can run the big steam locos and passinger cars on? Anything elece that I shouln know or watch out for befor I begin this task?
I know I will be getting some flex track and a number of turnouts. Mike
Excellent question. I’ve been in both scales, so I’ll share my experience.
9 3/4" radius in N is like 18" radius in HO. That means 4-axle diesels, 40’-50’ cars, small steam, etc.
11" radius in N is like 22" radius in HO. 6-axle diesels will work (though they’ll look awkard) as will medium steam.
I had both 9 3/4" and 11" radii on my old layout but I found them too restrictive. Now I use 13 3/4" minimum radius.
First off, thanks Mike for asking the question and thanks Dave for your answer. I started an N scale layout back in the 60’s. Was in the Navy then and so never really finished it. My future Erie is going to be N scale so even though I had built in N before, it will still be a new experience. Ken
I just picked up an out-of-print “Design Handbook of Model Railroads” by Paul Mallory on eBay.
There is something refreshing about the straight-forward approach to model railroading 40 years ago in the budding time of N Scale, and; before the days terms like multi-level, helix, and mushroom came into more common practice.
Taken from Chapter Section 1.2 - Space Avilable Versus Scale:
“The amount of railroad possible in a given area is inversly proportional to the square of the scale ratio. To duplicate a given N scale layout in HO would take 3.4 times as much area…”
Taken from to Chapter Section 6.2 - Curves:
Figure 2 - Minimum Standard Gauge Radii
Sharp radius street car - N = 2.62" - HO = 4.8"
Conventional street car - N = 3.8" - HO = 7"
Heavy street cars & small interurban - N = 5.44" - HO = 10"
Common interurban & industrial - N = 7.5" - HO = 13.8"
Short cars & locos on tight prototype yard - N = 9.8" - HO = 18"
All but longest cars & locos - N = 13" - HO - 24"
Any model equipment - N = 22.9" - HO - 42"
Tight heavy steam locos - N = 26.9" - HO = 49.5"
Sharp prototype mainline curve - N = 39.2" - HO = 72"
Taken from Chapter Section 6.2 - Curves:
“Do not forget the overhang of cars and locomotives on curves. See section 6.9 for increased clearance required on short radii curves.”
Here is a link to the contents of Paul Mallory’s “Design Handbook”…
http://index.mrmag.com/tm.exe?opt=I&MAG=BOOK&MO=5&YR=1979&output=5
P.S.: This book has virtually all the math formulas and charts needed for trackwork. Also, note what would seem to
N scale is roughly 1/2 of HO. So figure, 9 and 3/4 is close to 15-16 inch curve in HO. I’m going to use 15s on my current layout becuase they are of a good size, They don’t eat up too much space. and stuff looks good on them. Just about anything N scale will run on 9 and 3/4s. I ran an Athearn SD70M, 2 Atlas Articulated racks, an Mico-trains rack, and a con-cor rack on an oval that was 9 and 3/4s. They look horrible but can do it
If you do the math, you get that 9 3/4" in N is almost exactly 18" in HO (17.93").
Must be the new math or something; but 2 x 9¾" = 19½". That is 3½" to 4½" larger – a significant diffference.
[Into phone booth, strip off street clothes, become Super Pedant]
Actually, N scale is 54% the size of HO (54.375% to be precise), so you need to divide 9.75 by .54 to get the proper ratio. A 9.75" radius curve in N scale is the equivalent of an 18.06" (rounded to the nearest .01 inch) radius curve in HO scale. An 11" curve in N is the equivalent of a 20.37" HO curve. Dave Vollmer’s radius of 13.75" is the equivalent of a 25.46" radius HO curve.
That is all. We now return to your regularly scheduled forum thread.
[Return to phone booth, don street clothes, become Super Pedant disguised as mild mannered reporter for great metropolitan bird cage liner] [:D]
Andre
There is a webpage brought to our attention in this week’s forum which could be referred to as “Spookshow’s Model Railroading.” The author uses pictures extensively while sharing his recent experience building three N Scale layouts with what appears to be mostly sectional track at http://www.visi.com/~spookshow/trainstuff.html
On Layout #2: Spookshow says, “I finished relaying/reconfiguring my track. Most of my locomotives seem to be happy now, although there are still a couple (steam, naturally) that just don’t seem to like 9 3/4” radius curves in general, especially on the steep grades. Like I say, my next layout isn’t going to have anything sharper than 11" radius curves."
On Layout #3: Spookshow says, “This all turned out pretty well. By not trying to run all the way up to 2” along the back side (west) of the layout, I was able to keep all of the inclines to 2%. Better still, most of the curves are 19" radius (with a couple of 11 inchers thrown in for good measure, but zero 9.75" curves), so I should be able to operate longer trains and bigger locomotives more reliably…"
P.S.: On each layout page, you might consider doing a word search using: radius or sectional. Spookshow’s “talking out loud approach” is refreshing and insightful.
Curve math considers N Scale is 1:60 & HO Scale is 1:87:
To go from N Scale to HO Scale => 160/87 = 1.839
To go from HO Scale to N Scale => 87/160 = .54375
The info taken from Paul Mallory’s above chart in this thread uses the “54% math.”
If you haven’t seen how much layout, let alone diversity of engines and rolling stock, you can get with a 13.75" N Scale minimum radius on a 36"x80" hollow-core door, you should see Dave Volmer’s “N Scale Pennsy Middle Division” at
I don’t know if the old handbook has Ntrak standards in mind. It’s hard to disagree with over 30years of operation, with hundreds of modules built. For anyone getting into Nscale, it’s a few dollars well spent to be a member!
- Mainlines @ 18" or better. Yes the triple track looks boring, but can handle any type of equipment. 12" on the Mountain Div allows use of GP’s or other 4axle locos with 40-50’ freight cars. Normal 80’ passenger cars don’t look right here.
I’d forget looking for any good small DCC steamers. They don’t exist. Bachmann’s American suffers from poor pickup. You’d be better off using a cheater boxcar.
In converting a plan from HO to N, I’d use the same HO radius curves as much as possible. The wider ROW could be reserved to simulate sidings or a 2nd mainline track. Use the remaining space for scenery. Resist the temptation to cram in more track.
Be creative in looking for structures, cars & trucks etc from other places that could be used as scenery items. Get the sale coupon from Hobby Lobby, Michaels, etc this time of year to find cheap materials!
Good advice
I have a N scale layout and have a 9 inch radius. That is the bare minimum. I run six axles(Atlas SD-9,Atlas SD35) on it, but it is tight. I would recommend the loosest radius you can get.
-dekruif
I’m converting from HO to N, and for my new N layout, I’m using Atlas HO scale sectional track to help devise my track plans, using 18" radius curves as the minimum for the mainline. Best thing is, when you draw down the HO track outlines, they are the exact same width as N scale roadbed, so when it’s time to lay down the N roadbed, just follow the lines!