Working with PVA: brush or roller?

Different ways to apply PVA

Have you ever tried applying PVA to a sheet of paper or cloth using a brush? Unless a significant quantity of water, or paste is added, it is virtually impossible to do a good job. A stippling action can help; but the process is slow, so given how quickly PVA dries, the side of the sheet you started with will likely be dry by the time you reach the other end. Not to mention the unevenness of the application…

So what’s the solution, banish PVA? Certainly not. PVA is a quick-drying, high-tack synthetic adhesive which, if used properly, can make your life a lot easier. I use PVA for 99% of jobs, except when reversibility is required (paper repairs, gluing out spines of antiquarian books, etc.), or when a longer opening time is desired (moulding leather around bands, headcaps, etc.).

Another solution that comes to mind: adding paste or water to PVA to make it more runny, or more creamy/velvety? Sure, but that would defeat one of the main advantages of PVA, which is its relatively low water content. What’s the matter with water content? Excess moisture causes excess warp, causes materials to delaminate (e.g. the fabric layer separating from its lining material in book cloth), paste papers to disintegrate, and takes longer to dry.

Here’s a better idea: a roller.

Whenever I teach, I realise that the use of paint rollers to apply PVA is still a relatively unknown technique. Surprisingly, it’s still a kind of ‘trade secret’.

What is the fundamental difference between a roller and a brush? Let’s take a close look at what both actually do.

Brush - spreading action

As you can see, the action of a brush can be best described as a spreading action. It’s easy to understand that the thicker/gummier the ‘spread’, the more difficult the spreading will be. In order to succeed with (almost) undiluted PVA, one has to use a large amount of adhesive - which is what I did here - and this amount is excessive. This method is wonderful for paste, but not appropriate for straight PVA.

Brush - stippling action

Stippling is more akin to stamping; one applies a dab of adhesive with each press, one stamp at a time. While stippling can be fine in some cases, you can easily imagine the mess it would create on a larger sheet.

Roller

What a roller does is similar to a brush with a stippling action. It deposits adhesive one edge of the roller at a time. But it does so far more evenly than a stippling brush. Watch this next video to see how well this method works on a larger sheet of paper:

Advice:

• The position of the hand holding the paper, relative to the roller, is the same as when using a brush. The rolling motion is directed away from the point where the paper is being held down.

• Always roll from the inside to the outside, if possible never parallel to an edge.

• Rolling back and forth will pull the material and ruin the job — always roll in one direction.

• Notice how I hold the roller, similar to the way a big brush is held. This is a personal preference which I recommend, as it gives more control and more strength.

• Do not use foam sleeves, but instead choose the ‘Mohair’ (velours) type. It is a hard cylinder with short hair. The delivery is slightly less fine than with a foam sleeve, but fine enough, and more importantly those do not absorb as much adhesive, or water, which is easily spilled out uncontrollably with foam ones.

• Here I am using 10cm (3.94 inches) long roller sleeves, which I use almost all the time. Occasionally, if I must glue lots of exceptionally large sheets, I’ll use the wider ones (18 cm - 7 inches).

 

Happy gluing!

Ben