Mosazné trubičky 3

Metal where plastic is not enough

A brass tube replaces a plastic part that is meant to be hollow: the muzzle of a barrel, an exhaust, a pitot tube, an antenna or the hydraulic line of a landing gear. Unlike a plastic pin, the opening stays genuinely open, so a barrel does not come across as a blind cylinder. Brass also takes soldering, so a load-bearing structure that carries weight can be assembled from several pieces.

Working the material

Do not shorten a tube with nippers, as they would squeeze it and close the opening. The proven method is to rest the edge of a knife against the wall and turn the tube under it until it parts by itself. The burr left inside the opening is removed with the tip of a thicker drill bit turned by hand. The surface has to be freed of grease before gluing and before painting, because drawn metal carries traces of production lubricant.

Things to remember

• For painting use a primer intended for metal, as ordinary paint flakes off smooth brass
• Neighboring sizes in the range tend to be telescopic and can be slid into one another
• Store the tubes straight, as a thin-walled material bends easily

The name gives only the sequence number of the set, not the diameter. Check the particular size before ordering, therefore, as the range contains several sizes and the individual sets differ from one another.

Combining with other materials

• A wire can be slid into a tube to give a strong pin for a joint
• Several pieces of different diameters give a telescopically tapered antenna
• A soldered joint carries more than a glued one and suits load-bearing parts

Brass also differs from plastic in how it reacts to paint. Without a primer intended for metal the coat flakes off during ordinary handling, so it pays to paint the tubes before gluing them into a model.