I painted the one in 1st picture with a concrete colour then flat aluminium for the inside. They slightly overlap so the glue will stick both ends of the paper together aswell creating a more durable bond.
TT 120 Gauge Fence Panels & Concrete Posts 3d printed Unpainted
TT-PS013 Platform Set for an TT-ST005 Station TT:120 Gauge Laser Cut Kit
Hornby TT 120 Gauge (1:120 Scale) Track Oval Plus Siding Power Supply Contoller
TT3004M Hornby TT 120 Gauge (1:120 Scale) LNER Class A1 4472 'Flying Scotsman'
TT:120 Gauge 3D Printed Grey Farm Troughs (Pack of 5) – 1:120 Model Scenery for
Semi Detached Stone Cottages/House N/TT/OO/O TT:120 Gauge Scale Model Railway
