Profil trubka 3,2 mm

A tube with an outside diameter of 3.2 mm

This round hollow profile of opaque white polystyrene measures 3.2 mm around the outside, which in the manufacturer's inch system corresponds to one eighth of an inch. The standard length of one piece is 35 cm, that is, fourteen inches. The material is the same one plastic kits are molded from, so it behaves entirely predictably: it can be shaped with heat, sanded, drilled and melted with solvent cement.

What a hollow profile suits

A diameter of around three millimeters is among the most sought after of all. On ground vehicles it becomes exhaust piping, silencers, handrails and beams; on aircraft, engine exhaust pipes or the tubular structure of landing gear; on ship models, funnels, masts and railing stanchions. The bore moreover allows a trick that solid material cannot manage: a thinner rod or a narrower tube is slid into the tube and a sliding telescope is formed. That is how retracting gear legs, extending antennas, shock absorber rods and barrels with a separate muzzle inserted are built.

Cutting, bending and gluing

The cleanest cut comes from rolling a sharp knife on a hard surface; the wall is cut through all the way round and snaps off without flattening. Then square the end up with a fine file or sanding paper laid on a flat board. Hot air or steam will manage a bend, but only when the bore is filled with wire or sand, otherwise the profile will kink. The joint is held by liquid polystyrene cement, which melts the surface and literally welds the two parts together. Before painting it is enough to degrease the material.