OO Platforms

How much clearance do folks usually leave between the running rail and platform edge in OO? I could measure it from my models but it would be a bit sad if I later bought one that was wider over the valvegear and didn't fit :-) Guy

Reply to
Just zis Guy, you know?
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My friend here [now late friend :-(] did his by running a pencil along with a carriage to make the template. They seem to look OK on his old large layout.

Reply to
Andy Hewitt

That's how I'm intending to get the curves right, but I am wondering about the actual spacing.

The first platform is going to be a cop-out anyway, using a Metcalfe platform kit. For the main station I will be using rather more elaborate constructions. Guy

Reply to
Just zis Guy, you know?

The easiest way is to think in term of centre to centre spacing on double track.

Based on experience, NMRA clearance diagram works just fine for OO, because UK rolling stock is smaller than US. For curves, allow an extra

3/8 for 15" radius, 1/4" for 18", 1/8" for 24", and 1/16" for 36" radius (sorry, I haven't a clue what that means in terms of "radius 1", etc, as over here we work in actual radii.) If you make a quick'n'dirty graph on 1/4" or 5mm squared paper, you can interpolate for other radii. NMRA
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NEM norms should be close, but note that European rolling stock is intermediate in szie between UK and N. American. NEM:
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And of course you can check out the prototype, and convert:
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dimensions are metric, and they don't allow for the tight model curves.

cheers, wolf k.

Reply to
Wolf K

I found that 5mm was good for the largest locos and longest carriages down to a radius of 60 cms but actually based on 80cms. The worst locos were the Scot/ Jubilee/Patriots etc because of their front steps which actually can swing quite a significant distance across the line of advance!

Peter A

Reply to
Sailor

true to big railway - Stanier had chalk fitted to cylinders of a Crab to check all places civil engineer said Black 5 wasnt wellcome. Wonder if that was the first time civil engineer was forced to reveal exactly why a loco wasnt allowed on a route.

Cheers, Simon

Reply to
simon

Interweb search only finds a suggestion for 1/8", which happens to be the centre line of a standard pencil :-) (or at least the one I measured here).

Yes, I think I'll be looking at Metcalfe stuff too.

Reply to
Andy Hewitt

Excellent, just what I was looking for. Thanks. Guy

Reply to
Just zis Guy, you know?

Peco plastic ones with Plastikard might be acceptable. Guy

Reply to
Just zis Guy, you know?

I found that 5mm was good for the largest locos and longest carriages down to a radius of 60 cms but actually based on 80cms. The worst locos were the Scot/ Jubilee/Patriots etc because of their front steps which actually can swing quite a significant distance across the line of advance!

Peter A

I had some -very- tight curves to add a platform to on the inside of the curve so I took the longest item of stock, attached a pencil to the side at the centre and used that to draw the line, for an outside curve it'd be at the end of the longest item. That worked for me, but if the locomotives stick out disproportionately more there might be a problem with them (although a quick check with a card template based on the curve would show that).

Regards

Mike

Reply to
Mike Smith

The worst locos would be 4-4-0s and 0-4-4Ts in reverse. (small drivers, short rigid wheelbase and long overhang) Of course a 4-2-4 (GWR) or a

4-6-6t (DR) would also be bad! On one of my early scenicked layouts I built for tank locos and short passenger rolling stock. Fell in love with a Pacific in my local S/H model shop and managed enough pocket money and tradables to manage to carry it home. It was surprising just how may places the big cylinders wouldn't clear and how much rebuilding was required before it would do a complete circuit.The worst bit was not leaving enough clearance on the curves in front of the backscene!

Greg.P.

Reply to
Greg.Procter

Not necessarily. If the bogie works as on the prototype with proper side control and carrying the weight of the front of the engine, you don't have the overhang problems.

The ex- Bristol & Exeter 4-2-4 tanks actually ran like carriages. Bogies were pivoted at the centre with no side play, and flangeless drivers with wide treads.

Don't mention Dean's GWR 3251 0-4-4 tanks. They had the same problem as a long wheelbase OO 0-4-4T. No side control on the bogie and a short coupled wheelbase that made it wobble from side to side. They wouldn't stay on the track and were rebuilt as (IMO) handsome small-wheeled sandwich framed 4-4-0 tender engines.

Reply to
Christopher A. Lee

I would use Scalescenes.

MBQ

Reply to
manatbandq

=A0

..

The body is rigid and will always overhang on the much tighter than scale curves found on most models.

MBQ

Reply to
manatbandq

" snipped-for-privacy@hotmail.com" wrote in news:c89a49dc- snipped-for-privacy@m26g2000yqb.googlegroups.com:

Three-ply laminated with some plasticard - or for the terminally deranged (I can say this as my 7' platforms were made this way) three-play with a scim of plaster over the top then scribed.

Reply to
Chris Wilson

The only British 0-4-4/4-4-0 models I can picture that meet those criteria are of Diesel outline ;-)

Good point - would a model constructed that way go around R1 curves?

Reply to
Greg.Procter

Obsessiveness can be soothing when taken in small doses.

I'm about to pour a single malt, and settle down to an hour of nicely done teevy.

So good night all,

;-)

wolf k.

Reply to
Wolf K

The P4 guys do it, as do many of the 7mm guys.

Most of my 7mm engines are either 0-6-0s, 2-4-0s or 0-4-2s with a rigid (but compensated) wheelbase.

The only bogie engine is a Dean single built from a GW 150 limited edition kit from DJB. The driven and trailing axle are equalised by making the ashpan like a bogie that only pivots vertically. The bogie truck has a nice lost wax casting for the bolster, with springs on either side of a rubbing plate that carries the weight of the front of the engine.

Basically, it depends what kit you build. The better ones do this, and you can also buy the necessary bits from other suppliers.

I don't know. The only 4mm model I have seen was actually built like an 0-10-0 and powered as a 1A1A1. It went round the sort oc curves you get on a fiddle yard - station - fiddle yard layout.

I know you're in the antipodes, but if you've ever managed to get to the NRM at York there are a pair of driving wheels and axle on display outside the museum, on the way in, from one of these.

Reply to
Christopher A. Lee

Radius is the BIG difference! Show me a P4 layout using circa 360mm radius curves and I'll eat my entire collection of hats!

The driving and rear carrying axles are the equivalent of the 2 rigid (horizontally) driving axles of a 4-4-0 or 0-4-4.

I mostly build my own as I'm into old-time German plus HO L&Y.

Not the same sort of overhang on an all-driver loco as on a short wheelbase, long overhang loco like a 4-4-0.

York railway museum is definitely on my list of UK highlights.

Reply to
Greg.Procter

Crichel down. When I saw it, it had a GE tram engine and a small saddle tank. Only small locomotives but it had 2' radius reverse curves and a Y-turnout with a 1 in 2 frog angle.

Yes, but they're not rigid. It makes it like the diesel outline models you describe, except that one bogie has side control and the other only pivots vertically. DJB's 4-4-0s I've seen work the same way. When I was still in OO I toyed with the idea of building a GWR City (using a plastic Airfix kit body) with a coupled motor bogie having limited horizontal rotation - you can hide a lot behind the outside frames. The most visible compromise would be wider slots for the axles but these would be hidden by the wheels.

This was to overcome the problem of the outside frames limiting the bogie's side play and let it go round fairly tight curves. It really would be like a bogie diesel.

I had previously had a white metal Dukedog that was built the old fashioned way - like a rigid 0-4-0 with a long front overhang and a bogie that just went along for the ride - and wanted something better.

I also had a Triang Dean Single with its horrible frame cutouts and wanted something better than that, too.

Reply to
Christopher A. Lee

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