What can I get around a 3'3" curve?

[Lacathedrale]

I've got space for a layout, and I don't I'll ever have a larger space in my life again - 28' x 7' in a finished loft (see other thread re: whacking up some quick baseboards), however I'm yet to settle on a gauge - I was looking at Peco bullhead for expediency's sake - but of course less track required ( and some not awful experiments done already) means I could potentially look at O gauge in that space too. I know I can get an end-to-end layout without much fuss, but I was trying to think of a way to get a continuous run. There are two caveats:

 

1) the eaves of the roof and some structural beams mean I need to situate the layout where the width of the room is only 7' - so slightly less than that is the maximum radius.

2) I could take a pretty extreme gradient (say, 8%) and have the roadbed descend on the curve to sneak out and under the beams (probably extending the radius to more like 4')

 

In terms of stock, of course I'd love to run A3's, Black 5's and Class 40's - but realistically, what can I expect to get around these curves? Please note they are NOT going to be sceniced, probably hidden by a curtain of sorts - and simply bracket two 17' scenic sections so looks/etc. aren't that important.

 

 

[Nearholmer]

I’ll not comment regarding rtr finescale locos and stock, but will for coarse scale, where the answer is: everything that has been commercially produced in quantity. If you want to see a 9F that goes happily around 2ft radius curves in 0, have a look at my thread.

 

I personally find the sight of really big locos on really tiny curves a bit eye popping, but my eyes seem OK with 4-4-0 or 0-6-0, and most tank engines.

Edited September 22, 2018 by Nearholmer

[81A Oldoak]

Ixion Fowler 0-4-0DM. I have had one round less than 24" radius, but the overhang is outrageous.  AC Models in Eastleigh has some. 

 

 

[Lacathedrale]

^^ Oh no

 

Maybe an end-to-end is a better option then - I was hoping for a 33 and Mk1, or maybe an 0-6-0! I don't really want to be stuck with light railway tanks and industrials if I can get away with it.

 

 

I’ll not comment regarding rtr finescale locos and stock, but will for coarse scale, where the answer is: everything that has been commercially produced in quantity. If you want to see a 9F that goes happily around 2ft radius curves in 0, have a look at my thread.

I personally find the sight of really big locos on really tiny curves a bit eye popping, but my eyes seem OK with 4-4-0 or 0-6-0, and most tank engines.

 

Your thread is a constant source of pleasure, but I don't think I'd want to delve into that myself really - I like the traditional airfix-style modelling aspect alot. I actually have come back to your thread a few times in the last months - great work.

[47606odin]

Realistically you would be wanting an industrial or short wheelbase shunter, but depending on era, you could still trip rakes of HAA’s with couplers extended or 16t minerals between an exchange siding and pit head or quarry. You will struggle to get any standard gauge bogie locos round such t a tight curve, however I was able to run a Heljan 47 and 33 on Peco set track radius ( can’t remember what radius that is, but I think that’s bigger than your room) and the locos were on their limit

Edited September 23, 2018 by 47606odin

[Andrew P]

Realistically you would be wanting an industrial or short wheelbase shunter, but depending on era, you could still trip rakes of HAA’s with couplers extended or 16t minerals between an exchange siding and pit head or quarry. You will struggle to get any standard gauge bogie locos round such t a tight curve, however I was able to run a Heljan 47 and 33 on Peco set track radius ( can’t remember what radius that is, but I think that’s bigger than your room) and the locos were on their limit

It's 40.5 inch Radius, / 81 inch Diameter, and I have it and it looks tight.

[F-UnitMad]

I did a few tests on my O Scale layout where most curves are 3ft radius.

The Mnerva Pannier Tank took it ok, was probably just about at it's limits. 'Standard' 4-wheel BR wagons were also fine, & my Heljan 'modern' 4-wheel stock also got round, pulled by the Pannier, coupled up & no buffer locking, although I'd strongly recommend sprung buffers on everything. Sorry, I didn't take any photos.

But anything longer - forget it. My Heljan 31 & 37 could manage the curve on their own, but the overhang was ridiculous and it would be impossible to run stock with them. The only way you'll get a 33 and Mk1 coach to go round a 3ft radius curve together is with original, unmodified Lima & Triang BigBig stock.

The alternative, & why I get away with sharp curves, is to model American outline:- With stock on trucks (or 'bogies' in English - stupid word!! ) buckeye couplers and no buffers, 3ft radius is no problem for most 2-rail Scale diesel models & modern rolling stock, I mention that as the vast majority of US O is 3-rail coarse (VERY coarse!!), which will go round sharp corners as per Nearholmer's post above.

I have of neccesity tightened one curve right down to about 26in radius at it's tightest, in fact, & the only US stock I have that can't manage it is my long 6-axle SD40 Diesel.

 

 

But then, that engine can't manage some of my more exteme hand-laid 'rough track' either.

 

 

I appreciate you might not have the slightest interest in American trains, but it is an interesting comparison in prototype design philosophies, that can help or hinder the space-starved modeller. My layout which is 17ft x 8ft would not be possible with British diesels.

[Nearholmer]

OK, I said I’d keep quiet on finescale, but .......

 

Peco set-track is very much the radius you are talking about, and I’d be mightily surprised if you cant’ get small

0-6-0 round it very happily, which gives a lot of choice, both diesel and steam. Peco invested in making this track because they know that trains will run on it, and it will sell!

 

Find a friendly local model shop, and get them to try it on the counter, or try the local club.

 

As regards couplers, you might need to use ‘drop link’ instead of scale three-link in order to be able to propel safely without buffer-locking, but they are dead-easy to make, and I think someone might make an etched version.

 

What you are mooting, 0 using small locos, short vehicles, nominally fine wheels, and modest curve radii is “the coming thing”, and one a couple of people demonstrate the potential with ‘railways of the month’, it will take off like wildfire, to the consternation of the ‘0 is impossible on less than 6ft radius’ brigade.

[Lacathedrale]

Thank you guys, I appreciate the feedback.

 

F-Unit, I dont dislike american railways (I've had lots of layouts (see Modelling Miscellany thread) infact the only 'layout' (that is, 8" x 2' display plank) that ever got finished was a Burlington Northern refuel depot, but really I'm trying to capture a spark that will keep me going and I think British is the way to go. 

 

AndrewP and Nearholmer  - maybe all is not lost. There's a club with an O gauge layout exhibiting next month so I will check there! Thank you again

[F-UnitMad]

No doubt about it - British outline O Scale is booming at the moment!

& I'm all for "Knickers to the 6ft minimum radius Brigade" too

[81A Oldoak]

All Minerva and Ixion locos are designed to negotiate PECO Setrack curves, including the GWR 57XX/8750 0-6-0PT. PECO 0 Gauge Setrack curves equate to 23" radius in 4mm scale, which a great many enthusiasts are content with. I am seriously considering building a continuous run light railway based on Setrack curves in a space of 15'6" x 7'9" and I have been looking at plans in my 1971 edition of PECO 60 Plans for Small Railways".  

 

Regards,

 

Chris

[Nearholmer]

Having seen the standard of your work in the recent magazine article about your layout, if you do build and make visible a ‘minimum radius’ circuit layout, I would expect it to be a ‘mould breaker’ that starts a big new trend in 0.

[mike hughes]

I've done a commission for a Hampshire unit that went round the Peco setrack ok, just have to remember to have couplings out far enough inbetween

 

Michael

[ba14eagle]

I have just bought one of the new batch of Heljan Westerns and have been looking at minimum radii just as you are.

I have read in another thread on here, that someone got diesels with a co-co wheel arrangement ie Heljan 31, 47 & 53, around Peco radius 2 curves (40.5") without any problems. Have another search through the topics and Im sure you will find its not as bigger problem as some might have you believe (although it will always look slightly ridiculous, as someone is sure to point out to me!).

 

Here is a link to the page:

http://www.rmweb.co.uk/community/index.php?/topic/102199-Heljan-o-class-31-minimum-radius/?hl=%2Bheljan+%2Bminimum+%2Bradius

Edited September 24, 2018 by ba14eagle

[Lacathedrale]

Interesting - so potentially with some sprung couplings it could work - that's very pleasing to hear   I am considering that maybe aiming for the absolute minimum clenched-teeth limitations might be a mistake in a permanent loft layout though - maybe end-to-end there and a roundy-round for the patio, with a comfortable 6' radius.

[Nearholmer]

I think a huge amount depends on what sort of trains "do it for you", and how comfortable or otherwise you are with gross compromise.

 

If you are 'into' small locos, short wagons, and coaches up to about 48ft, the minimum radius thing can not only work well, but look good. When you are inside a circuit, with the train going round you, even 48ft coaches don't look eye-watering.

 

However, if you are 'into' big locos, longer coaches, bogie wagons etc, while you might be able to squeeze things round tight curves, ludicrously tight curves if you go 'coarse', things do tend to look severely 'toy-train', and if you don't like the 'toy train' look, it isn't going to make you happy.

 

Personally, and is all a very personal set of choices, I don't think a Crompton and some Mk1s, for instance, would like right on minimum radius, even if it can be done, but an EE350, some mineral wagons or a few 6W milk tanks and a brake van look fine.

[Ian Kirk]

The late CJ Freezer postulated a layout in 00 which used, I think, 15inch radius curves either end which were hidden, as were the sidings at the back, with the visible part of the layout at the front on the long straight. That way you can operate long locos and coaches providing they have the right clearances but don't have to look at them on the unrealistic curves.

In O  gauge with 3ft 3 radius either end you could still get over twenty feet of "straight" layout  and the same for your storage sidings.

 

best wishes,

 

Ian

[Steamport Southport]

It might be worth having a look at this.

 

https://peco-uk.com/collections/publications/products/your-guide-to-o-gauge-railway-modelling

 

I only had a brief look at it, but seems ideal for anyone who is starting out in O Gauge. It has trackplans included.

 

 

 

Jason

[brianusa]

 

However, if you are 'into' big locos, longer coaches, bogie wagons etc, while you might be able to squeeze things round tight curves, ludicrously tight curves if you go 'coarse', things do tend to look severely 'toy-train', and if you don't like the 'toy train' look, it isn't going to make you happy.

 

 

 

Kevin, I thought you were our friend!    Tinplate will never please the 1/43 fraternity but those of us with no such qualms can enjoy large complicated layouts with sharp curves (Lionel 031) which provide lots of layout in a small place.  US locos which can negotiate such small radius have serious overhang but that's part of the deal and if you more than a circle of track, its the way to go.  My main lines are 048 and 054 which satisfies the 'sweeping curve' urge and needed to allow the bigger Hornby locos to haul expresses.

 

Brian.

[Nearholmer]

Let me rephrase, then:

 

However, if you are 'into' big locos, longer coaches, bogie wagons etc, while you might be able to squeeze things round tight curves, ludicrously tight curves if you go 'coarse', things do tend to look delightfully 'toy-train', which, if you like the 'toy train' look, will make you exceedingly happy.

 

I seem to be happiest with something that isn’t finescale or outright toy train.

Edited September 24, 2018 by Nearholmer

[alastairq]

Gauge widening, anyone?

[F-UnitMad]

Gauge widening, anyone?

Why? Getting stuff to actually take a 3ft radius curve isn't the problem. Like I said, my HJ 31 & 37 can do it. The issue is couplings. A 24" curve for OO has been mentioned. While this sounds quite generous, I doubt anyone in 4mm scale would be using scale couplings on 'big' stock with such a curve.

You would need a 7mm version of the Tension Lock coupler to get big stuff round a 3ft curve with them all joined together, in the manner of a 'train', rather than one at a time. Wilst various auto-couplers are available, I doubt if any of them could do it either, since they've still been designed with the "6ft minimum radius" parameter in mind. Kadees wouldn't either, with UK buffered stock. The O equivalent of the Tension Lock coupler just does not exist - thankfully!!

[brack]

Gauge widening, anyone?

Given how well stuff runs on 31.5mm track you could argue that this already occurs.

[Lacathedrale]

Well, just to put another perspective - does this mean that (caveats on shunters, tinplate and diesels aside) unless someone has a large, flat garden or is a club member with access to a tennis court - typically The average 0 gauge modeller doesn't have a continuous run?

[brossard]

I would be inclined to agree that an 0 gauge continuous run with comfortable curves would have to be at least 12' wide and as long as you like.  That seems like a tennis court or a garden to me.  Obviously not available to most, but perhaps possible in a club setting if there is one near you.  It really depends on what you want to do and that probably dictates scale.  Most 0 layouts seem to be branchlines with a fiddle yard/sector plate at one end.  An acquaintance was kind enough to allow me to run my stock on his layout at a show this spring and it was the most fun I have had in a long time.

 

John

Edited September 25, 2018 by brossard