Ramps and helixes
To get a train from one deck to another, you need track that climbs. The catalogue carries two kinds, both under the Ramp section of the piece picker:
- Inclined straight (ramp) — a straight that rises over its length.
- Helix — a curve that climbs as it turns, so a train spirals up in a small footprint. A full turn returns to the same spot on the plan, one deck higher.
How they work
Both pieces follow the same rule as the rest of the catalogue: connector A sits at deck level and connector B is lifted by the piece's rise. Because the snap engine matches connectors in 3D, the top of a ramp or helix mates with a piece sitting a deck above — no special "bridge" tool, it just connects.
Select a ramp or helix and the Inspector shows its rise, grade %, and pitch (plus length for a ramp, or radius and arc length for a helix). In 3D the body tilts (ramp) or spirals (helix) to match the climb, so you can eyeball whether a loco will clear the deck above.
Incline track you already own
You don't have to buy a dedicated ramp. Just like propping a length of track on risers in real life, you can incline track you already have:
- Select a connected run of plain straights and/or curves (one piece works too — click one, or shift-drag a marquee over a chain).
- In the Inspector's Properties, type a grade % into the Incline field and press Enter.
The whole run becomes a continuous climb: each straight turns into a ramp and each curve into a helix, and the run's elevation restacks along its joins so the pieces stay mated end-to-end. The grade is spread evenly across the run, so a 2% climb is 2% on every piece. The anchored end stays put — if the run is joined to the rest of your layout, that end holds its height and the run climbs away from it; otherwise the lower/front end anchors.
Type 0 (or click Level it) to flatten the run back to ordinary track. It's one undo step either way.
Inclined-from-owned pieces behave exactly like catalogue ramps and helixes — same 3D tilt, same Inspector readouts, same grade check below.
Spotting a grade in 2D. A climb is purely vertical, so an inclined piece looks identical to a flat one from the top-down 2D plan. Inclined pieces are marked with small uphill chevrons (pointing toward the high end) so you can see the grade — and exactly which pieces carry it — without switching to 3D. Switch to the 3D view to see the actual slope.
Bridge two decks by dragging a piece between them
You don't have to pre-incline a piece to span a gap. Put one piece on a lower deck and another on a higher deck, then drag a plain straight or curve so one end snaps to the lower piece and the other end lands on the higher piece's connector. The planner sees that the free end needs to climb, inclines the piece automatically so it rises exactly the deck-height difference, and joins both ends in one drop — the new piece becomes a ramp (or helix) with the right grade, no manual incline step.
It works in either direction — drag up out of a lower piece or down out of a higher one; whichever end you snap first becomes the anchor and the other end climbs or descends to meet its target. Start the drag from the piece on the active deck (the one shown in the top-bar deck switcher) so the first end snaps cleanly. If the climb would be steeper than 25% — too steep to be buildable — the planner won't force the join: the piece drops flat with just the first end connected, and an amber hint tells you it was too steep so you can use a longer piece or a helix instead.
Grade is measured along the climb
Grade is rise over the distance travelled — a ramp's length, or a helix's arc length. That arc detail matters: a full-turn helix ends up directly above where it started (zero straight-line distance), but it still climbs the whole way around, so its grade is computed over the full turn, not the (zero) shortcut.
The grade check compares that figure against the trains you're building for and flags anything too steep to pull. A gentle helix passes; a short, steep ramp gets a red warning — exactly what you'd want to catch before laying real track.
Today's pieces are placeholders
The first ramp and helix SKUs in the Hornby OO set are synthetic proofs-of-concept, not real Hornby parts — they exist so you can build and verify multi-deck climbs now. Real manufacturer incline and helix data are on the way.