Tank Emblem

The Tank Emblem is a thin cap, 73 mm across and 4 mm thick, that goes over the existing round badge of 70 mm on a motorcycle tank. The question was simple: can a tank go all black without taking off anything that will not go back on later?

The design. The cap covers the badge and stays clear of the paint. Its skirt reaches only 1.2 mm down the edge of the badge, so it never touches the tank. The cap sticks to the face of the badge with foam tape. Tired of it? Peel it off. The face is divided into four quadrants inside a ring. Two are plain, two are filled with straight grooves 1 mm wide and 0.6 mm deep, 2.4 mm apart. A 1 mm bevel runs around the front. Two are needed, one for each side of the tank.

What makes it hard. Black on black has no colour to draw with. The pattern is made of shadow alone: light falling differently on the grooves than on the plain fields. That is why the cap prints with its visible face down. The face takes the texture of the build plate and no supports are needed, because the hollow back ends up on top. Grooves three layers deep are fine work for a 0.4 mm nozzle. At 1 mm they are wider than two printed lines. A part that lives outdoors in the sun is no job for PLA. It calls for ASA or ABS, which is ordered per job.

Where it stands. The 70 mm diameter comes from the published size of the original badge, with 0.6 mm of clearance. The 1.2 mm of room for its domed centre is an estimate. So a first print has to show whether the cap sits flat. The print file is ready; the images are renders.

It shows what you can ask for on a motorcycle or a car: a cover or a trim piece made to fit what is already there. If you would like something similar, ask for a quote.