A simple height gauge/marker.

[LDO]

I first saw a tool used for the same thing in a Fine Scale Modeler article about detailing a Lear Jet model. The tool was used to mark out the dark stripes on a light-colored aircraft. When viewed from the side, the strip was a straight line. Due to the compound curves of the aircraft, it looked much different from other angles. From below, the engine nacelles had an egg-shaped line painted on. That tool was purpose built. Mine was thrown together from what was at the modeling bench. Crude, but it does work.

 

 

It is a Machinist's square with a couple of small clamps holding a sharpened pencil. If you get a machinist's square, make sure it has the thick bottom side. Some have a very thin cross-section that will not stand up by itself. The model is a Victorian spacecraft (from a role playing game). The front part is the wheelhouse. I made a mark at the upper limit of the port hole window, then ran the line around to the side, so I could make sure the window on the side is at the same level.

This tool has many uses. It can mark out cut lines for chopping a top or sectioning a body. Make one horizontal line on a car body, then shim the front end a bit to mark out lines for a pie-cut section.Mark out the location of custom windows on both sides of a '70s custom van.
 

 

Edited August 25, 2017 by LDO

[Snake45]

Cool tip! Looks like it works great.

You can also do the same thing by putting a pencil (or a scriber, XActo knife, razor saw, whatever) in the pages of a thick book.