Playback & Navigation

Railcut uses familiar NLE-style playback controls. Most shortcuts pass directly to After Effects, so you’re working with AE’s native playback engine throughout.

Playing your comp

Space — RAM Preview

Press Space to start a RAM Preview. After Effects renders frames into memory and plays them back at full frame rate. Press Space again to stop.

Note

RAM Preview in After Effects renders from the current playhead position to the end of the work area (or until memory fills up). If your comp is long, the first play-through might be slow while AE caches frames.

J / K / L — Shuttle playback

These keys pass directly through to After Effects:

Key	Action
L	Play forward
J	Play backward
K	Stop
L + L	Play forward at 2× speed
J + J	Play backward at 2× speed

J/K/L are not captured by Railcut — they go straight to AE’s keyboard handler, so you can use them even when the Railcut panel has focus.

Frame-by-frame navigation

Key	Action
→ (ArrowRight)	Step 1 frame forward
← (ArrowLeft)	Step 1 frame backward
Shift+→	Step 10 frames forward
Shift+←	Step 10 frames backward

Jumping to clip boundaries

Key	Action
↓ (ArrowDown)	Jump to next edit point
↑ (ArrowUp)	Jump to previous edit point

These find the nearest clip in or out point across all tracks and jump the playhead there. Useful for quickly stepping through cuts.

Go to Start / End

Key	Action
Home	Jump to the start of the composition
End	Jump to the end of the composition

Go to In / Out

Key	Action
Shift+I	Jump playhead to the work area In point
Shift+O	Jump playhead to the work area Out point

Scrubbing

Click anywhere on the time ruler (the timecode bar at the top of the track area) and drag left/right to scrub the playhead. AE updates the current frame as you drag.

You can also click directly on the playhead line and drag it.

Selection Follows Playhead

When Selection Follows Playhead is enabled (toggle in the toolbar), clips that touch the playhead automatically become selected when you stop moving. This is handy when navigating by edit point and immediately acting on a clip.

Toggle it from the toolbar — it looks like a cursor icon with a waveform.

Animated playhead during preview

During RAM Preview, Railcut animates the playhead to show the actual playback position in real time. The playhead moves across the timeline as frames play back. When preview stops, the playhead stays at the last played position.

Tip

If the playhead drifts to a position you don’t expect after preview stops, it’s because RAM Preview stopped short of the work area end (usually because AE ran out of cached RAM). The playhead shows exactly where playback stopped.

Estimate Playhead Position During Playback

In Settings, you’ll find an Estimate Playhead Position During Playback option. When enabled, Railcut uses frame-time estimation to smooth out playhead animation during RAM Preview. This is useful on slower machines where actual frame polling can lag.