Small Layout for O 16.5

[kebang]

This little layout is 5ft 6in x 3ft. This small footprint is only achieved by giving the revloop (blue track) a radius of 13in. I've never bent flexitrack before - is such a tight radius possible?

I've measured the height of the first carriage I've built & its a fraction under 7cm., so I've allowed the height of the the upper baseboard at 9cm. This creates a slope of 4.1deg. Any opinions as to if this will be too much for a hornby 'Smokey Joe' pulling 2 hornby 4 wheeled petrol tankers (well that's what the chassis for the coaches were cannibalised from!)

What is the smallest OO/Ho rad track available? It would be nice not to have to bend flexitrack that tight if I can avoid it.....

[Mountain]

There is no problem bending flexible track except that the outer ends where the rail joiners are tend to push outwards so need to have extra support, and if bent too sharp the sleepers can go at awkward angles and in extreme cases will narrow the track gauge.
When I bend flexible track (I use Peco code 100 rail), I try to keep the whole curve in one go so I avoid the difficulties of rail joiners pushing outwards, though my curves are more extreme. I have found that by using PCB sleepers soldered in position it really "Sets" the curves so they handle more like sectional track curves in that they stay in the curved position. This can be done even if one solders in just a few sleepers spread across the length of the curve, but for the curves you are considering, they are not seriously sharp so should work OK with normal flexible track.
The curves are not really the concern. The gradient may pose more of a problem. You will probably get away with it if but it may be a close thing between what the train can pull compared to the height gained. One of my locos, having added weight and a heavier Triang chassis should pull well up most gradients, but not sure all locos will. I've not done much experimenting with gradients, but I'd say your design maybe the limit for most locomotives to pull about three or four coaches up the gradient. It all depends on how heavy the coaches are. Resin kits are heavier then plastic and while plastic coaches need added weight, resin coaches rarely do. The locos are normally heavier after conversion compared to the donor locos weight so this does help, and one can add a little weight to improve traction, but I'd not go overboard in that the more weight is added, the more strain there is on the locos gears.
As a general guide, it is better if the loco can wheelspin if overloaded. If it is too heavy to wheelspin, one has overdone it somewhat!

I've looked again at the plan and you have around room for two coaches and a loco, maybe three small coaches at a push to allow your loco to run round so it looks more promising. Longer loads would pose a problem. If possible, start the gradient at the earliest possible position to gain enough height to just clear the maximum roofline of the tallest coach or loco by the time it first crosses over the track below.

[Mountain]

Another thought to the concept of your plan. The idea you have has been to maximise the running length in your available space. You could, instead make things simpler which will give you more room for any buildings and scenery. I know it is a swings and roundabouts situation....
My layout is slightly shorter then 7ft x. 2ft wide. (Approx 210 x 60 cm) which is on two boards to help in being portable. It also helps as I can work on one board at a time. If you see the basic track plan it is visible on this picture, though it will have a siding going from the scenic loop through the curve towards a future board (Hence why I decided to build a diamond crossing through the curve which I also include a picture of, and no doubt you have probably seen the pictures before).
The boards one side of the board will have scenery along the length, and the other side will have no scenery for loco storage, and control panel use etc.
Now my plan is the other extreme in that I have opted for space for scenery which is unusual for me as I usually love to get the longest run as I can from my trains! The advantage also is I can run five coach trains (Shorter coaches) and stop in a station (Hence the passing loops) and have a train wait while I run a second train in the other direction to pass it. This in itself can add interest, along with the ability to stop a train, uncouple it from one end and couple on the opposite end to leave in the other direction should I want to. It also can be used as a siding to leave some waggons for a while. The extra siding going off the loop will provide additional interest for shunting and when I eventually build a third board, I can extend the siding further.

I'm not showing you my plan so you will copy it (Unless you want to) but I'm showing it as a different approach to the concept you have so that it gives a different approach to the limits of modelling in a small space. You have quite a luxury of having 3ft of width.
I could have made mine 3ft wide but portable boards can get heavy and cumbersome if I'd made mine wider.

[Mountain]

Here is my track plan and also some ideas in blue that may help you. See what you think about the blue plans.
Be aware with my plans for my layout (Plan 1 and plan 2) may be difficult to copy as my diamond crossing is home made, though it is not impossible with some thought if one has the extra width to do so. The dotted lines represent a board that I've not built yet but plan to in the future.
The blue plan with the terminus station area and the reverse loop may provide what you are looking for without the need for a steep gradient.you could slightly raise or lower that portion of board with the run round loop for a more pleasing effect should one desire. The good thing about the plan is you have an out and back run with a continuous run included in the plan.

[Emettman]

What is the smallest OO/Ho rad track available? It would be nice not to have to bend flexitrack that tight if I can avoid it.....

Notoriously Fleicshmann Modell 6020 track comes in a 250mm radius, 10".
No longer made, it can be found.

Playcraft/Jouef had track at 12.8" code 470 or 4700.
Similarly this is a second-hand hunt, but isn't rare.

Short vehicles and locos, the latter mainly 0-4-0 but a select few small 0-6-0's, will handle the 10" radius.
The bigger issue can be with couplings, particularly on longish 0-4-0's with a shortish wheelbase (the classic Hornby chassis, unless chopped!)

Chris

[Bufferstop]

Chris - I was pondering the problem of couplings on long overhangs, most situations can be accommodated when using the mini tensionlock with some sprung movement. Especially if hooks one end can be the rule. The one exception being the dreaded reverse curve. Which lead me to rewriting a saying one of our art teachers used to use, I replaced colours with bits of track.
"Left and right curves n'ere should be seen, 'less there's a straight bit in between"
His version wasn't funny either!

[Mountain]

My solution to couplings for tight radius curves are the drawing pin conversions. Here are a few. As long as the loops are sufficiently large enough and the buffers overhang the wagons they should work well. They are not automatically engaging like tension lock are (Though if I raise the loop and balance it, I can bang into a Wagon and the loop drops to couple) which can be a bonus if one wants to push waggons into a siding and leave them there! The only downside is that one needs a suitable "Shunting pole" to lift the loops so as to manually couple. The good side is these loops are easy to lift unlike trying to couple or uncouple 3link or screwlink couplings! Mine dont sway about.. They just swivel up or drop down.
I originally had the idea for these from the prototype couplings with the central buffer and two chains either side. I was going to make two chains that were fixed and join them with a wire across them but in the end I settled for a stiff wire loop made from a paperclip.
So there you have it. Paperclips and drawing pins! (Thumb tacks for USA modellers!)
Just a note. I hold the paperclip to the loco via those tiny metal clothes fasteners that I cut in half as they have ready formed little "O" shapes with a supporting wire. I just drill holes and glue into position. One could instead just use wire in an "U" shape and drill tiny holes and glue into position to hold the paper clip loops (Which need tiny loops formed at the ends). The pictures explain more.
I have made a "Jig" to help make loops. A few locos or waggons may just need individually sized loops made depending on the vehicle. The jig just speeds up making loops.
The little collars on the shaft of the drawing pin buffers are simply made from the small straws on cans of spray oil like WD40, GT85 etc. Most of mine came from GT85.

[Emettman]

Chris - I was pondering the problem of couplings on long overhangs, most situations can be accommodated when using the mini tensionlock with some sprung movement. Especially if hooks one end can be the rule.

I made some single hook modified Hornby couplings (with delayed action) which were fine for most combinations on 10" curves, but these had an "endedness" so didn't work with return loops or train turntables.

"No hooks on the loco" is not uncommonly seen, and does allow for more play on curves.

Or you go my Dr Frankenstein route and shorten the locos.

Chris

[Emettman]

This little layout is 5ft 6in x 3ft. This small footprint is only achieved by giving the revloop (blue track) a radius of 13in. I've never bent flexitrack before - is such a tight radius possible?

kebang, I've had a play and can't really do anything better in the space than what you already have, keeping the operation pattern and getting the incline run as long as possible.
With a clearance of 75mm, I reckon it comes out at 1/20 even with estimated minimum transition curves.
when drawing the tight return loop curves in Anyrail I used HO Jouef 470 curves at 12.8": obsolete but still generally available second hand.

3" longer or wider and I think I can get enough extra length before tracks have to cross to give a 1/30 gradient
The only other thing I can suggest is a simple train lift. That would give a nice 4" rise in say 6" more than the train length.
It's not monstrous engineering...
But even as I type I've realised this could also be solved be replacing the return loop with a single* track train turntable.
That might be even simpler as a fixed 180 degree is all that would be needed.

Still thinking,

Chris.

* oreven double track

[Mountain]

I'm more inclined to use a simple plan where space is tight. One could always add an additional off scene board for storage of trains in sidings just for running days, and unclip the board and store away when not in use.

[Emettman]

Here's a drawing with a train turntable, but needing no 13" radius track.

With only two positions solid stops would align the track easily, and the majority of the turntable would be under (removable) scenery.
The rest seems quite tidy.

Or, following Mountain's suggestion, simpler, on one level.

Here the passing station (with engine shed) is used to return trains to turntable. a train is probably held at the left-hand end to make room for this
Or simply forget the turntable and replace it with one or a pair of sidings as the others, with a good scenic break.

Chris

[Mountain]

The one on the same level. Was looking at the turntable idea and the size of the turntable. It looks like one can turn a small loco and three coaches on that. It would need scratchbuilding. One could always buy a ready made turntable, but one maybe down to a loco and two short coaches. The Hornby turntable maybe a bit rough and ready, but is does work and is easy to fit, as it sits on top of the board, and more importantly can be used without trhw side railings if one has wide locos. It also does not have a height restriction.
If looking at other makes of 00/H0 turntables check if they can cater for the width of cylinders (Almost double the width of 00 needed for some 0-16.5 locos) and the height issues. Also some turntables need a hole cut into the board.
It is an interesting concept that Emettman has made.
Nothing stopping one cutting a circular board and making a manual turntable. Just need some way to wire it up.

Let us know how your hunt for track is coming along. Hope you get some.

[kebang]

I'm now looking for a bigger space! Might try to redefine my objectives.......

[Mountain]

I'd like a bigger space but I daren't at the moment as whatever I build will need to move in the future. I've recently been looking through things as I am looking for something else I need, and I'm amazed by how much stuff that I have accumulated over the years! I'm starting to sort things through...Need a good sort out!

[Emettman]

It is an interesting concept that Emettman has made.
Nothing stopping one cutting a circular board and making a manual turntable. Just need some way to wire it up.

Five pounds or under, with adequate precision and weight-bearing.
https://www.ebay.co.uk/itm/300mm-360-DE ... xy63FS6iYS

Add top board with length to suit.
Wiring and alignment are trivial for a table that only has to turn 180 degrees *and then back again*, or with a bit more work the polarity change could be automatic

I've used one of these, but for the moment I can't find the photos!

Chris