How to Make Paper Mache Paste

Paper mache paste is flour and water. That is the whole thing. A box of craft glue costs money and does the same job slightly better, and for most projects it is not worth the trip to the shop.

McCall Johnson from Mr Otter Art Studio makes hers by eye rather than by measuring, and the ratio she lands on is roughly two parts water to one part flour. Start with as much water as you want finished paste, then add flour until it looks like pancake batter.

The thing worth knowing before you start: add the flour slowly. Paste that has gone too thick takes a lot of water to bring back, and it keeps thickening as it sits.

The Paper Mache Recipe

One cup of flour to two cups of water makes enough paste for a medium balloon project with some left over.

• Water: room temperature, straight from the tap. Warm water dissolves the flour a little faster but makes no difference to the finished paste.
• Flour: plain all-purpose. Self-raising works and is a waste of money. Bread flour makes a slightly stronger paste because of the higher gluten.
• Ratio: 2:1 water to flour by volume. Thinner soaks into the paper better, thicker builds up faster.

Measure the water first and add the flour to it, never the other way round. Flour tipped into a dry bowl and then flooded with water clumps instantly and you will spend five minutes chasing lumps.

How to Make Paper Mache From Start to Finish

The paste is one third of the job. Here is where it fits.

1. Build an armature. That is the skeleton your paper wraps around - a balloon for anything round, cardboard and masking tape for anything that is not. Balloons are easiest because they deflate and pull out.
2. Tear the paper, do not cut it. Torn edges have a feathered fibre edge that blends into the layer underneath. Cut edges leave a visible ridge that shows through paint. Strips about an inch wide.
3. Dip and squeeze. Pull each strip through the paste, then run it between two fingers to strip off the excess. Sodden strips take days to dry and can go mouldy.
4. Lay the strips in alternating directions. One layer horizontal, the next vertical. That cross-hatching is what makes the shell rigid.
5. Dry between layers. Two to three layers, then let it dry completely before adding more. Four to six layers total for something that holds its shape.
6. Prime before painting. A coat of white acrylic or gesso hides the newsprint and stops the paint soaking in unevenly.

Newspaper is the standard because it is thin and absorbent. Paper towel makes a good final layer, since it smooths over the sharp edges of the newsprint and gives you a surface that takes paint well.

Getting the Consistency Right

Pancake batter is the target. It should coat a spoon and run off it in a steady stream rather than dripping in blobs or pouring like milk.

Too thin and the strips go floppy, the layers slide around, and drying takes forever. Too thick and the paste sits on top of the paper in lumps that dry into visible bumps.

Remember it thickens as it sits. Paste that looks right when you mix it will be noticeably stiffer twenty minutes later, so err on the runny side and check it again before you start dipping.

Paste Variations Worth Knowing

Flour and water is the default. Three variations solve specific problems.

• Add PVA glue. Half a cup of white school glue stirred into a batch gives a harder, more water-resistant shell. Worth it for anything that will live outdoors or get handled.
• Cook it. Simmer the mixture for a few minutes and let it cool. Cooked paste is smoother, tackier and keeps about twice as long, at the cost of ten minutes and a pan to wash.
• Add salt. A tablespoon per batch slows mould growth. Useful in a humid house or if a project will take a week of drying.

Wallpaper paste is the other common option. It is stronger and it keeps well, but most brands contain fungicide, so keep it away from projects children will handle.

Fixing Lumps, Mould and Slow Drying

Lumps that will not break up: push the paste through a sieve. It takes a minute and it works every time. Prevent them next batch by adding flour in small amounts with the whisk already moving.

It smells sour after a day or two: that is the flour fermenting, which is normal and not harmful, but it means the batch is on its way out. Mix fresh.

Fuzzy spots on a drying project: mould, and it means the layers went on too wet or the room is too damp. Move it somewhere warm with moving air. A fan pointed at it cuts drying time by more than half.

Still soft after two days: too many layers went on at once. There is nothing to do but wait, so next time dry properly between every two or three layers.

How Long the Paste Keeps

Covered in the fridge, three or four days. On the worktop, about a day before it starts to smell.

It separates as it sits, which is not a problem. Whisk it back together and check the consistency again, because the flour that settled out will have made the bottom thicker than the top.

Mix what you need. It takes two minutes and costs pennies, so there is little reason to store much of it.

Once the paste is made, paper mache pumpkins are a good first project, and salt dough ornaments use a similar flour-and-water logic in a form you can bake.