HOW TO MODEL TARMAC AROUND COMPLEX TRACKWORK USING FOAM
This is probably the easiest method for modelling around complex trackwork. I have used card, styrene and just loose grout. This method is easy to cut and does not distort with damp like card (mine has swelled over the years causing clearance issues).
It’s simple because you can just press it down on the trackwork and then cut along the impressions. None of those nasty gaps left when you try and measure the uneven and irregular areas. Easy. It comes in grey, it’s easy to trim in situ if you need to with a sharp knife blade and it has a great texture – what’s not to love!
The only downsides are that it does dent easily and solvent-based products will cause it to distort ruining all your hard work. That means you need water-based glues, fillers, and paint.
Craft foam – check the size but mine is around 2mm thick from HobbyCraft. It comes in A3 and A4 sheets so you can avoid too many joints.
Sharp knife (I use a #11 X-acto blade but anyone will do). They do blunt relatively quickly especially if you are trimming in situ so be prepared to sway your blade is trimming is not going well. It’s also easier to trim if there is a paint layer on it.
Acrylic putty – I used Deluxe Materials.