Tight circle in 009/HOe

[ianp]

What is the tightest circle of track that I could lay sensibly using 009/HOe gauge track? The Peco setrack range offers track at a radius of  23cm. Is that the tightest functioning radius known to mankind? Or could I go a bit tighter with flexible track?  I wish to model a small, rural, French, narrow gauge scene in 009/HOe. Thanks.

[ITG]

Can’t speak for 009/HOe, but in general I think it’s considered that bending flexi track to tighter than set track radii can be tricky, mainly I hear (as I’ve never tried it) as kinking / dog legs can appear. Particularly a risk at any rail joins. It might also depend on what stock you plan to run, even in narrow gauge.

[Dungrange]

The tightest radius is the one that your stock will go round. 

 

As an example, Heljan's 2-6-2T is quoted as needing a minimum radius of 11" (28 cm) in this article - https://www.keymodelworld.com/article/heljans-lb-manning-wardle-prairie.  I have also seen other references to a minimum radius of 12" (30.5 cm).  However, if your prototype has mainly short 0-4-0 diesel type locomotives, then you may well be able to get them to reliably run round tighter radii.  However, the tighter you go, the less stock you will be able to accommodate and you'll also need to consider the type of coupling that you plan to use.  Tight radii and large end throw on stock will be a problem for most couplings.

[DavidB-AU]

Depends on the stock you intend to run. Freezer's original OO9 rabbit warren layout used 6" radius. Some have been built even tighter for very short wheelbase locos and wagons.

[Keith Addenbrooke]

Hi @ianp.  The advice shared above is all good.  It may be worth posting your question in the Narrow Gauge Forum as well, where there may be others who can help too.  My own small H0e layout keeps to a 9” (228mm) minimum radius so I can turn 180° on a 60cm wide board.  I also use a Peco Setrack point, but I’ve been running more mainline European trains, so don’t want too tight a radius.  If your plan is to run short wheelbase locomotives and tram engines using MinitrainS chassis (or equivalent) then I’m sure you could go a bit tighter than that without trouble.  Three things that might help:

 

Depending on your space constraint, using Flextrack may allow you to plot simple transition curves that not only look better than sharp Setrack turns, but may also help achieve a tighter minimum radius in places by easing into and out of them.  As Narrow Gauge trains often run slower, that helps anyway.

 

Secondly, a yard length of Flextrack can easily be long enough for a complete U-turn with room to spare in H0e, making it easier to avoid rail breaks in the sharpest sections.

 

Finally, depending on which type of Flextrack you plan to use, a tip I’ve been shown is to cut some additional breaks into the webbing between the sleepers under the outer rail to make smooth bending easier.  I didn’t need to do it, but some very tight curves have been achieved using that approach.  

 

Hope this helps, Keith.

Edited June 30, 2022 by Keith Addenbrooke

[simonmcp]

I've seen it recommend to take the rail out of the sleeper base and use a bending jig before sliding it back into the sleeper base.

[DCB]

Do you want a circle or just a half circle, It it's a circle then really set track is as tight as you can reasonably get, 

though  you can tighten the radius of set track a bit by cutting the webs between sleepers and tweaking the rails tighter, (or wider)  before filing the rail ends "square"   You end up having perhaps 7 or 7.5 curves per circle not 8, but the track stays put, if you use flexi it dog legs and you can't get the join anything like true without an awful lot of fiddling.     If you only want 180 or 270 degrees then 150mm should be do able in N / 009 , I have used 300 mm in 00 and a model shop in Newton Abbott had an 00 display layout 2ft wide which class 47s and the like ran round 180 degree sub 12" curves

 

Provided the curve is sharp enough to be made from one piece of flexi  track you should be OK  as Its the transitions from sharp curves to straight  which cause the problems. Joins on very sharp curves just don't work    12" radius the maximum for a one metre for flexi turning 180 degrees   I believe some 009 track comes in 18" lengths which is medium useless for bigger than 6" so I would substitute N gauge flexi or use 1 metre  N gauge rails in 009 sleepers, much as I do in 00  mixing rails recovered from the garden railway where sleepers have gone brittle with sleeper bases recovered from off cuts of track.

[cnw6847]

I've got a little test track using 5 1/2" radius but only very small 0-4-0s and small wagons will go round it.

Minitrains locos are fine round it.

 

 

[009 micro modeller]

A few thoughts and possibilities:

 

Original Egger/Jouef track was 5 1/2” radius, if I remember correctly. I’m not sure if the new Minitrains set track is as tight as this.

 

Tomix has some 103mm radius set track and Kato has set track in similarly (but not quite as) tight radii. Both of these have N scale sleepers and integral ballast roadbed though - but some of them are also available as inset tram track which may be of interest. I have some somewhere (I think it’s Kato and about 127mm radius but can’t remember) as at one stage I had planned to use it off-scene on a layout to create a tight but hidden curve, facilitating a continuous run.

 

Jelly Models ‘joke tracks’ can go down to about 2” or 3” radius, and I have run a Kato 11-103 chassis on one of these, even though it initially appears that it might be too long. As others have mentioned already though, conventional couplings can’t be used on really tight radii. That said, I have seen a layout with Peco flexitrack bent to about 6” radius and only using small 4-wheeled locos and stock (Nigel Lawton diesels, Minitrains skips etc.), including ordinary couplings. As Keith mentions above, some people manage to get down to tighter radii by cutting some of the plastic sleeper web on the inside of the curve, but you can’t cut too much of this as there still needs to be something to keep the track in gauge.

 

I’ve mostly stuck to 9” as a minimum radius though, and others would suggest 12” or sometimes even larger. Are you looking at small radius track because you’re hoping to create a continuous run in a small space?

Edited July 2, 2022 by 009 micro modeller

[Keith Addenbrooke]

13 minutes ago, 009 micro modeller said:

A few thoughts and possibilities:

 

Original Egger/Jouef track was 5 1/2” radius, if I remember correctly. I’m not sure if the new Minitrains set track is as tight as this.

 

Tomix has some 103mm radius set track and Kato has set track in similarly (but not quite as) tight radii. Both of these have N scale sleepers and integral ballast roadbed though - but some of them are also available as inset tram track which may be of interest. I have some somewhere (I think it’s Kato and about 127mm radius but can’t remember) as at one stage I had planned to use it off-scene on a layout to create a tight but hidden curve, facilitating a continuous run.

 

Jelly Models ‘joke tracks’ can go down to about 2” or 3” radius, and I have run a Kato 11-103 chassis on one of these, even though it initially appears that it might be too long. As others have mentioned already though, conventional couplings can’t be used on really tight radii. That said, I have seen a layout with Peco flexitrack bent to about 6” radius and only using small 4-wheeled locos and stock (Nigel Lawton diesels, Minitrains skips etc.), including ordinary couplings. As Keith mentions above, some people manage to get down to tighter radii by cutting some of the plastic sleeper web on the inside of the curve, but you can’t cut too much of this as there still needs to be something to keep the track in gauge.

 

I’ve mostly stuck to 9” as a minimum radius though, and others would suggest 12” or sometimes even larger. Are you looking at small radius track because you’re hoping to create a continuous run in a small space?

I think the current MinitrainS track may be made for them by Peco (so will have a 9” radius).
 

 Japanese N-Gauge track is a good suggestion (I hadn’t thought of that), but whether it would look right for a rural French NG layout would be a question?  Thinking about it, Kato have a 6” / 150mm radius range designed for their Glacier Express models - which are specially designed to cope (and have bogie mounted couplings, I think).  Extending the idea, Kato do a tram track range inset into roadways which is tight radius too - and no lesser modeller than Lance Mindheim has used it for an American N Gauge layout (so it must be OK 🙂), Keith.

Edited July 2, 2022 by Keith Addenbrooke

[009 micro modeller]

2 minutes ago, Keith Addenbrooke said:

Japanese N-Gauge track is a good suggestion (I hadn’t thought of that), but whether it would look right for a rural French NG layout would be a question?  Thinking about it, Kato have a 6” / 150mm radius range designed for their Glacier Express models - which are specially designed to cope (and have bogie mounted couplings, I think).  Extending the idea, Kato do a tram track range inset into roadways which is tight radius too - and no lesser modeller than Lance Mindheim has used it for an American N Gauge layout (so it must be OK 🙂), Keith.

That’s why I mentioned the tram track originally, as I thought for some roadside-running French NG lines it might be quite suitable. I think if using the non-tram versions it would be very difficult to disguise the sleepers (probably more difficult than when using Peco track with N scale sleepers, for instance) and integrate the roadbed into the scenery, but this sort of track might be OK if you were using it exclusively on non-scenic parts of the layout.

 

The old Egger/Jouef track also has steel rail (originally intended to work with the adhesion magnets fitted to the locos I think), which for some people is a disadvantage. I had some at one stage and found it difficult to cut and solder, so in the end I ended up using it on a layout that only had unelectrified track (the layout used cable haulage so no locos). I’m not sure this track is a good option anyway, as although the sleeper spacing is better than the Japanese track, it would all have to be sourced second hand.

[Andy Hayter]

On 30/06/2022 at 06:37, DavidB-AU said:

Depends on the stock you intend to run. Freezer's original OO9 rabbit warren layout used 6" radius. Some have been built even tighter for very short wheelbase locos and wagons.

 

 

That is exactly the point.

 

OH built her own HOe layout as a first attempt.  Inadvertently she laid one corner with what is probably just under a 6" radius - 15cm or a bit less.  This was with flexitack - so it is easily possibly to build a layout with such curves.

 

0-4-0 and 0-6-0 chassis traverse without issue as does all of the hauled stock - rigid 4 wheelers and bogie stock.  

 

The 0-6-6-0 Mallet tank I built also traverses without issues.

 

However amid all of this positive, the Billard autorail kits will go nowhere near going round such a tight curve.  

 

 

 

 

 

 

 

 

[Andy Hayter]

To make the point

 

 

 

The Mallet makes the curve with no problem but the autorail behind has no chance 

Edited July 2, 2022 by Andy Hayter

[Andy Hayter]

Just read the review of the just released REE Billard A 80 D autorail where it states that the minimum radius for H0e is 228mm.    Coincidence that it is just (2mm) smaller than the PECO track?

[D9020 Nimbus]

The Peco track actually is 228mm radius (actually 9ins).

 

I have had problems with the Heljan Manning Wardles on 435 mm radius so I suspect that 1ft = 305 mm will be very problematic. But then, they are longer than a "Terrier"…

[Stanhope]

On 02/07/2022 at 09:54, Keith Addenbrooke said:

I think the current MinitrainS track may be made for them by Peco (so will have a 9” radius).

I don't know who makes it (I doubt Peco; Minitrains, maybe?), but it isn't "directly compatible with" Peco 009 track (to quote the Minitrains website).

 

It is 140mm radius (so: just over 5½").

[ColinK]

Kate do N gauge unitrack with a radius of 117mm.  I’ve used it on my 009 micro layout (below).  The Kato 4 wheel chassis run fine on it, but couplings need to be modified.

 

[nswgr1855]

As others have rwplied, it depends on the size of the equipment you wish to use. The AMRA minimum radius standard gives the answers for minimum radius. https://amra.asn.au/wp-content/uploads/2019/05/AMRA-Minimum-track-radius-standard.pdf