goldfish

Did you have the same problem without the couplings? I know from personal experience that you can push Stroudley 4-wheel coaches though unmodified Peco Setrack points with a Terrier without problems, and that is with a reverse curve. The "footprint" of a wagon wheel is about 12mm and the check rails are 30mm+ long which should be long enough to guide the wheels through the frog.

Out of curiosity, have you tried loose shunting your stock through these points without couplings?

What better way to start the day, than with an over the top AI description and an over exited seller : - https://www.ebay.co.uk/itm/335322814448? I always thought FLAWLESS meant without flaws. Don't paint chips count as flaws?

It is 0 gauge tinplate, so it must be Hornby : - https://www.ebay.co.uk/itm/204720510778? Pity about the prominent Bassett Lowke logo.

Another chiseller looking to make a killing : - https://www.ebay.co.uk/itm/266733347373? The price is about twice that of a set in reasonable condition. "Loco runs but very slow, needs some oil and service." is probably short hand for the piston in the smoke generator has succumbed to mazak rot and the mechanism is slowly destroying itself. The box lid looks like it has seen better days as well.

Maerklin also used 26mm gauge and called it 00 Apparently based on the locomotive Maerklin made for Raylo.

Better to stay in imperial. I make 3mph to be 4.4 ft/sec. A 65 ft turntable has a circumference of 204.2 ft. So one revolution takes 46.4 seconds. So 1.29 rpm. In reality it can take a lot longer : - https://www.youtube.com/watch?v=fLL-SExCHTc (2:36 - 4:39)

Rails of Sheffield are currently offering "Dapol 7P-020-CLUB1 Set of 3 Stroudley 4 Wheel Suburban Oil Lit Mahogany Passenger Coaches" for £179.95. Just the thing to go with your £125 Terrier. https://railsofsheffield.com/products/set-of-3-stroudley-4-wheel-suburban-oil-lit-mahogany-passenger-coaches

Possibly because they are comfortably past their three score and twenty, and failing eyesight and reduced manual dexterity mean that more prototypical couplings are physically beyond them?

There is no reason why for there not being an equivalent to the tension lock coupler in 0 Gauge, about from a lack of market interest. Indeed 00 tension lock couplings can be used with 0 Gauge with reasonable success. These are Bachmann (?) 00 couplings mounted styrene strip fitted through the 3-link receptacle. Actually a discarded project because simple drop links are more reliable and much less trouble. All that is needed to prevent buffer lock is to keep the buffers from interlocking, and that requires some reliable means of maintaining them at the correct distance apart. Realistically anything bigger than a Terrier or a 4-wheel coach is unlikely to work on curves smaller than Peco set track, although tenders are reasonably short wheelbase and that can help solve the problem.

Would these qualify as exceptionally tight curves? Not fine scale, but fine scale compatible. The points are 170mm radius, and the wagons can be pushed through the points in all directions. It is just a simple matter of using appropriate couplings. In this case over long swivel, drop links. The track is ETS Tram Track and so has check rails as standard.

I was simply pointing out that it is a very conservative design criteria. It is reassuring that you are designing for smaller radius curves, perhaps you should try the 88DS through ETS 627mm radius points, the Dapol Terrier manages surprisingly well. In reality almost any 0-4-0 will run around 2' curves, the problem is getting them to do something useful, and that almost certainly requires the couplings replacing to prevent buffer lock. The Dapol Sentinel Shunter is perfectly at home on 2' radius curves, so the 88DS should be equally at home.

According to the Accurascale website the Ruston 88DS has :- This is an incredibly conservative minimum radius to be using as a design specification or consideration for this type of locomotive. In fact it is equivalent to designing a 4mm version to run on radius 4 set track. With such a short wheelbase it would be able to traverse ridiculously small radius curves, although it would be reduced to doing no more than chasing its tail on them. It would certainly be perfectly be capable of running through the 24" / 600mm radius curves recommended by the G0G for dock areas, industrial, and factory lines, which are a 88DS' natural environment.

Doesn't a Train Set become a Model Railway when the owner gets too old to admit to playing with Toy trains ...

Peartree wheels and axles are insulated, so no additional insulation is required.

If you mean Peco ST-725 1028mm radius curves, that is what it is designed to work on, so yes. That said, in their publicity videos they only show it going forwards and there isn't a reverse curve in sight. https://www.youtube.com/watch?v=lHcNALJRdn0

Having established that the Dapol Terrier and Sentinel Shunter can successfully traverse ETS curves, albeit with some restrictions, I thought it would be interesting to put together a layout see what could actually be done in a space of 2.4m x 1.6m. The result is a small oval with a Light Railway style station on one side of the oval and a shunting plank / fiddle yard on the other. The paper template represents the Tower Models / Bachman platform which is the only r.t.r. one I could find. The points are arranged to avoid reverse curves, and the sidings will each accommodate three short wheelbase wagons. The Terrier is confined to pulling everything, attempting push anything through the curves simply results in buffer lock. The Sentinel Shunter can move short wheelbase wagons around without restriction. Within those limitations it provides a reasonable amount of operating potential in a size only a little larger than a double bed. It is very limited though, even a Lima 4f will not go through ETS points. For a more practical layout using Lima 700mm curves would be a much more sensible solution. From a purely practical point of view, any small radius curves are incompatible with 3-link couplings. For reliable running they have to be replaced with couplings that maintain sufficient distance to prevent buffer lock.

There is an interesting article "SIZE, THEN GAUGE, THEN SCALE" by Nicholas Oddy and Stuart Mangleson available through the Glasgow School of Art website that discusses the origins of model railway gauges, complete with references. https://radar.gsa.ac.uk/5706/

The centre to centre dimension is only baffling when viewed from a modern perspective. It should be remembered that Maerklin did not start their design process with a clean sheet, there was already an established product base of floor trains before Gauges 1 and 2 and to an extent the train came before the track. As the Germans had only recently gone metric so I cannot see there being any great enthusiasm for using another unit of measure. If there was any foreign influence at that time it would be more likely to come from France not Britain.

I find that a Belt and Braces approach works best... Unfortunately this is not easily possible with most rolling stock, but where it is, as with Leeds Bakelite stock, it is extremely successful. Allowing as it does both loose and coupled shunting. Although 3-link couplings can be soldered or glued together to act like single link couplings they are not very successful. To function properly a single link coupling must form a rigid strut when coupled to a hook, if there is excessive side play the tendency is to push the wheels sideways off the rails. The broader section of the single link coupling near the end is not there for show, it forms a solid lock with the hook to keep the hook and link in line. They knew a thing or two a century ago, some of which has been forgotten.

You don't have to confine yourself to 0-4-0s, I have been running a Dapol Terrier around ETS 627mm (24.7") radius curves with no problems. Including through the double reverse curves through points on my shunting plank. It is even possible to pull Dapol Mainline 4-wheel coaches around these curves, but they cannot be successfully pushed around them, nor will they cope with the reverse curves. Buffer lock is an obvious problem with the Terrier, but is easily overcome by ensuring that the Terrier is only coupled to a wagon fitted with wide buffers.

It is reassuring to know that the major traders recruit staff who are highly knowledgable in the field of model railways, or perhaps not... https://www.ebay.co.uk/itm/134902005391? "UNKNOWN BRAND 'O' GAUGE BR GREEN DIESEL LOCOMOTIVE *BATTERY POWERED*" Anybody care to enlighten them?

I should have spotted that, the straight coupling rods are a give away. The 0 gauge version has cranked coupling rods to give sideways clearance for the centre wheels. This is a suspicious one : https://www.ebay.co.uk/itm/404758859380? "Appears 100% complete. 100% original. In very good condition, some light chips/marks to original paint. Axles/wheels are straight. Untested but see no reason why it should not work. Clean and bright." It is a pity about the missing tender coupling. The strangely bulging cab roof and partially pulled tabs that are indicative of a possibly broken spring. Could that be a reason for it being untested?

One for connoisseurs of real tat. "This Lima steam carriage and tender was originally black and has been distressed to create a unique train." No sign of a carriage, but the tender is certainly distressed. https://www.ebay.co.uk/itm/176202249661?