Advice on gauging/widths of OO models

What bearing does speed have on the question?

Depends on the width of the rolling stock, and how sharp is the entry to the next curve.

=>Is that the distance between the rail centres?

Yes - it's the standard way of specifying track spacing.

(The "6 foot way" thing is purely UK, and even there it's a misnomer.)

Just to add to the mix - the standard HO/OO cork rail bed that many modellers use is just under 2 inches wide, though of course you can always trim it...

Rather depends on what prototype dimension you are talking about. Double track spacing should be 11' 3" centre to centre, or 45mm for

4mm scale. This is irrespective of what gauge you use and with vehicle 9' 3" over handrails leaves a scale 2feet between them.

If you chose as your prototype dimension the 6ft between outsides of rails then in 00 you will have a below standard spacing, a centre to centre of 10' 1.5" and under a foot between vehicles.

Just remember to keep to centre - centre dimensions when you distort the scale/gauge ratio.

Keith Make friends in the hobby. Visit Garratt photos for the big steam lovers.

38mm, center to center. (unless you run something like a Hornby Dublo crane!)

You obviously don't run your A4 at 24 volts! ;-)

I'm sure it exceeds 126mph at 12 volts!

I still don't see the relevance of speed to clearance on straight track.

The loco will yaw around the short coupled wheelbase and the relevant cylinder will extend way past it's intended width.

My A4 is tender driven - the tender wobbles on its traction tyres.

Fit suitable sized traction tyres from Marklin or Roco.

Regards, Greg.P.

Vacuum effect and wobbling.

No. It depends on the prototype you are modelling. If "full speed" is 30 m.p.h. (for an unfitted freight) the track spacing on the prototype will be different from a HST running at a "full speed" of 125 m.p.h. in order to avoid problems caused by the circulation of air around the moving trains as they pass each other. It's worse in tunnels.

If you are not modelling any particular prototype, you should still consider what the prototype would do in your particular circumstances.

(It also depends on the loading gauge, so the TGV that someone mentioned in another message will run on wider spaced track than a HST because the loading gauge is wider.)

Fit suitable geared ales and wheels and do away with stinking traction tyres.

-- Cheers Roger T.

of the Great Eastern Railway

"John Sullivan"

WHAM! As two fast running steam hauled trains passed each other in a tunnel.

Ah, the Good Old Days.

-- Cheers Roger T.

of the Great Eastern Railway

quoting Mark W. =>> What would you say is the minimum space required for two straight and =>> parallel tracks so that all RTR rolling stock can pass by at full speed? =>

=>38mm, center to center. (unless you run something like a Hornby Dublo crane!)

That's 9ft 6in in OO - a tad tight on the clearance, wouldn't you say?

I think you meant 48 mm, or 12ft in OO.

He has one of those feeble tender drives - you can't get enough weight in to get it to push the loco, let alone a proper train, with metal tyres. Been there, done that!

Geared ales? - I've drunk some with a little bite. ;-)

Regards, Greg.P.

No, the question was "the minimum space", not minimum clearance. Add your minimum clearance to the 38mm. The widest British prototypes were 9'3" = 37mm at 1:76.2 plus a millimeter for the gauge less flange to flange width = 38mm.

Regards, Greg.P.

"Gregory Procter" <

Stupid spill chukka.

-- Cheers Roger T.

of the Great Eastern Railway

Hard to find in Canada.

I took the traction tyres off my Hornby Fowler 2-6-4T, so it no longer waddles. It still has enough traction to pull 3 Bachmann Mk1 Suburbans. I'm just fitting Kadees to this train. You can drill a 1.8mm hole in one of the NEM Kadees and just screw it on in place of the Bachmann hook-and-loop. See

and On the loco I used No. 5 Kadees shimmed up by 0.8mm. It's tricky getting them the right height without fouling the buffer beam or buffers.