A compass (diagram 3) (or pair of compasses) is a technical drawing instrument that can be used for drawing circles or arcs. As dividers, they can also be used as tools to measure distances, in particular on maps. Compasses can be used for mathematics, drafting, navigation, and other purposes. Koh-I-Noor Combined Eraser– natural rubber – soft red side for erasing pencil marks and a hard blue side for erasing pen lines.

First kneading: the hardest one, almost impossible like trying to tear a plastic eraser apart, never even tore into pieces, never got smooth or held together, was a lot of work, I made a usable piece by twisting a small portion at a time. Second kneading of small piece next day: hard. Set Squares are used to draw accurate angles. The most common set squares are 45 degrees and 60/30 degrees. When using set squares they should always be used along with a T-Square. The Set-square rest on the straight edge of the T-Square and this ensures that the angle is drawn straight and with accuracy. Diagram 4 – Set squaresa. Rubber erasers (they used to be made of natural rubber and now some are synthetic rubber)- middle in the scale of firmness. A few contain abrasives like pumice – but those are usually just the rhomboid-shaped school erasers. The abrasives are designed to erase biro ink. Rubber erasers feel a bit powdery to the touch and this bothers some people a great deal. It’s not always easy to tell some synthetic rubber erasers from plastic erasers if they don’t say anywhere, in that case, I go by the powdery feel. Rubber, gum or vinyl erasers can cause smudges as graphite is a lubricant and the act of rubbing, (especially if there is lots of graphite to be removed), can smear the graphite across the paper and drive it deeper into the tooth. Use these erasers only after you’ve removed excess graphite with the kneaded or putty eraser. Faber Castell Green Dust-Free Eraser (‘dust-free’ means that crumbs clump together) (phthalate free) It is hard to erase graphite under a watercolour without damaging it. The best advice is to draw very faint lines you can barely see and when painted over they won’t show. Or let the graphite lines show a bit as part of the painting.

Faber Castell Round Eraser, Platinum-plated (comes in a gift box, for the artist who has everything) Another element in deciding what eraser to use is the kind of paper and type of medium you want to erase. If it’s coloured pencil or ink, then a rubber eraser containing abrasive silica particles is most likely to succeed. Once again, remove any excess pigment first with a putty or kneaded eraser.

Erasing Hard or Soft Pastels – Most erasers work to remove pastels (hard and soft) but many people have had mixed results. If your surface is very textured you may have trouble and if your paper is very soft you will need to be careful. Many people find that a putty rubber works best, again using a press and lift action. Kneaded erasers are self-cleaning. By kneading them, you enclose the charcoal pigment inside the eraser and use a clean part.