Simple and effective: the gravel aid from DM-Toys in 2 mm thick MDF (medium density fibreboard).
Lasercut Kit Dimensions: 50x24x29 mm (WxDxH). We recommend gluing the gravel aid together. When using the gravel aid, you should take care not to push it too much on the tracks, but only pull it backwards, otherwise the material could suffer.
The gravel aid is currently available in 2 versions. The gravel aid is offered for tracks without embankment (A00001) and for tracks with embankment (A00002). The ballast aid allows easy coding of code 80 and code 55 tracks.