What to consider when buying watercolour paper PAPER When you start watercolour painting there are so many things to consider, paper becomes a personal preference as to make, surface and weight. The traditional and most common paper to paint on is Cotton, or cotton and wood pulp (known as RAG content,) these make up most of the papers, but also bamboo and agave are becoming popular. Watercolour paper is heavily sized. This sizing is like a glue that seals the paper and stops its surface absorbing all your paint. Artist quality paper has good archival quality meaning your painting will last. There are different formats available: sheets, pads and blocks. Sheets need stretching, using watercolour paper tape, and can be cut to customised sizes. Pads are usually spiral bound or gummed on one edge, pre-cut to a certain size. Blocks are gummed on 4 sides with a small opening to remove the page once painted, these don’t require stretching and will remain flat when the image is dry. They have less sheets than the pads but give a stretched paper finish. Stretching paper prevents the paper cockling (buckling) when dry, it will stick cockle while wet but will dry flat, unstretched paper will cockle and this will remain as the painting dries. WEIGHTS OF PAPER The weight of the paper is important. Watercolour paper is mostly made in different weights, shown here in gsm (grams per square metre for metric), or British imperial lbs (pounds per ream) The weight indicated on the paper pack or pad is the weight of a full ream, so 140lb is the weight of 500 sheets measuring 22” by 30”. 190gsm/ 90lb, 300gsm/140lb, 425gsm/200lb and 640gsm/300lb. 185/190gsm is thin and needs stretching, 640gsm is similar in thickness to card and therefore doesn’t usually need stretching. In summary, and as a rough guide, I recommend that paper of or under 140lb needs to be stretched to avoid the paper buckling. PAPER SURFACE What the difference is between NOT, hot pressed & rough papers? These terms refer to the surface of the paper and its texture. Hot pressed papers have a smooth surface made by passing the paper between two hot cylinders. Great for lots of very fine detail such as botanical paintings. Cold Pressed or NOT (as in not Hot Pressed) papers have a slightly textured surface which is great for most types of painting. Rough the roughest surface. This surface is great for painting landscapes where a more textured finish is required. Telling the front from the back of your paper sheets can be difficult, however if your paper has a watermark, it will read correctly on the right side when held to the light. Usually there’s is little difference and either side can be used, but the right side will have more “tooth” or texture. Not every make of paper is the same and you will find a paper you prefer and a weight you are comfortable with. Stretching your paper You will need… a board (MDF 9mm thick is a good size) large enough to take your selected piece of paper. Paper, watercolour paper, ( as a rule paper over or around 600gms does not require stretching) watercolour stretching paper tape, gummed on one side and easy to tear, KEEP AS DRY AS POSIBLE when stored! Clean sponge Cold, clean Water How to …. Dampen the board by wiping with a damp sponge. Tear selected lengths of tape to fit your paper with overhang, Check your paper for the correct way round, look for embossed paper marks or watermarked name. Soak your paper well on both sides, you can use a hose or watering can for large pieces, or for smaller pieces a sink/bath of cold water, submerge your paper. Drain the excess water slightly. Place paper evenly on the board, some buckling will happen, try to keep it flat but don’t pull the paper flat, or try and smoothen out the buckles. Dampen the tape with a wet sponge. Don’t soak it, just LIGHTLY wipe with the sponge, don’t rub hard or you will remove the glue. Place the tape so half its width is over the edge of the paper and press down, do this for all four sides. Leave somewhere warm to dry. It should dry nice and taut/flat. To remove your painting from the board when finished, run a cutting blade halfway through the brown tape where it covers your paper, if you give yourself a 5mm margin where there is paper behind your tape, you will find the tape stuck to the board will remove easily . Excess tape can be removed by soaking it with water, then using a scraper remove the softened tape, wash the board with soapy water to remove the glue, let the board dry. You are now ready to stretch another piece of paper.
