This is a series of adapters of the OS railway O-gauge rail system.

The arrival of a grandchild prompted me to extract the old train collection from the attic One or two are age-appropriate but others not yet. The gift of a 3-d printer gave me an excuse to try connecting them all up, from push-along to detail scale. Of course when the good stuff is running she only gets to watch, but she still enjoys that. Then the toddler-proof trains come out and and she can do what she likes.

Rather than try to design adapters.for every combination of rail ends I have made adapters for each system to connect to the new OS Railway system. There are many implementations of the system on Thingiverse but my preference is the Timo Novak implementation (Viesturs version, thing:4368179) which seems to be stronger than some others.

Some of the adapters can be used back-to-back to make a very short length of track to fill in a gap in a random floor layout.

Uploaded:

• Adapter OS - Big Big Train (Triang Rovex) and clones ( https://www.thebigbigtrain.com/ )
• Adapter OS - Faller Play Train and Hit Train
• Adapter OS - Plarail, two versions: standard and short
• Adapter OS - recent cheap Chinese toy train track (01: hook points up)
• Adapter OS - recent cheap Chinese toy train track (02: two flat prongs)
• Adapter OS - recent cheap Chinese toy train track (03: one square prong)
• Adapter OS - recent cheap Chinese toy train track (04: Lionel prong and claw)
• Adapter OS - Brio, Ikea, Aldi and other wooden track
• Adapter OS - Hornby, Lionel and similar tin-plate tube track (the central slot is for an electric third rail but I have not tested that). This was inspired by the wooden SHC adapter that I used as a child, hence the photo.
• Adapter OS - Lima. Note that some trains that can run on the other tracks cannot run on Lima fine scale track due to the flanges bumping along the top of the sleepers. Also Lima track appears not to be intended for toddlers to play with on the floor.
• Adapter ramp for "Loco Remote" track. ( http://www.locoremote.co.uk/ )
• Cable jumper for OS track to allow printer and power cables to pass under a track around the notebook on the desktop. (working from home, you know!)
• Adapter Plarail - wood. This one is included with the OS adapters because it passes big O-gauge trains better than the usual adapters which assume that all trains are pushed by hand..

Note that most O-gauge rolling stock can operate on at least straight sections of any of these tracks, However push-along wooden trains and Plarail trains should stick to grooved track. Some powered wooden track trains (Mattel, 0-4-0) will just run on the OS track (and bounce along some others). Likewise some Plarail Thomas toys (the ones made in 1994 and 1995 with the battery in the tender).

These tracks are suitable for battery and clockwork engines, and toddler hand-powered of course. Steam is risky with plastic rails and obviously track-powered electric trains won't work here, although trains could be parked on unpowered sidings.

Also please beware of the risk of running rolling stock with solid metal wheels and axles on to two-rail electric track.

If I get around to doing one I shall post an adapter for the original Skaneateles Handicrafters (SHC) wooden railway later.

I would be interested to see how you have used any of these adapters in your layout, or in your child's toy box. If you have a photo please post a "Make". Also suggestions for improvements or new devces are welcome.

Edit 15 November 2021: added adapter for Hornby tube rail.
Edit 14 January 2022: added adapter for another recent cheap Chinese toy train track (02: two flat prongs).
Edit 15 January 2022:
. added adapter for another recent cheap Chinese toy train track (03: one square prong);
. added adapter for Lima fine-scale O-gauge track;
. uploaded the source code (openSCAD) so you can customize if you like.
. removed "this is a work in progress" warning.
Edit 18 April 2023:
. added adapter for "Loco Remote" track.;
. removed customizer link as it does not allow a choice of model.
Edit 13 December 2023:
. added adapter for another recent cheap Chinese toy train track (04: "Lionel" prong and claw);
Edit 19 February 2024:
. added a more compact version of the Plarail adapter.
. updated the SCAD file.

P.S. Why all the colours? To put it mildly, our UP mini printer is temperamental. So I like to print a test piece before committing to anything big or sensitive. I find that making a piece of OS-Railway track using whatever filament is intended for the project is usually enough to warm up the bed and predict if the printer can be trusted or not. Each success is another 100mm or 15 or 20 degrees of track.