Glue syringes are amongst the indispensable small wallpapering tools, it is therefore important to know about it before ordering wallpaper. As they are very reasonably priced, a glue syringe should be part of the basic equipment when you buy your wallpapering tools, so that it is always available if and when you need it. You can use it to apply small amounts of wallpapering adhesive when the wallpaper is already in place, or to remove excess glue from under the wallpaper. And you won't need to make any visible cuts in the wallpaper either, as the hollow needle creates tiny yet precise holes.
How to remove air bubbles and wallpaper paste lumps with a glue syringe
When hanging wallpaper, the biggest challenge is to avoid air bubbles. We use various tools, for instance wallpapering spatulas, brushes or smoothers to deal with this issue. But air bubbles cannot always be prevented and often appear in the worst possible places. There is a number of reasons why air bubbles come about; just check out our wallpapering guide What can I do to prevent bubbles and blisters?, which provides a whole array of helpful tips and tricks. The usual cause is either air trapped under the wallpaper, or a lump of adhesive.
Most of us wouldn't like to live with this accidental "bubble pattern" in our lovely new wallpaper as it impairs the visual effect. A cross cut is often the best way to deal with large air bubbles. Depending on the carrier material, the wallpapering paste is spread with a small brush onto the underside of the cut wallpaper (paper carrier material, please observe the instructions Re: soaking time), or directly onto the wall (non-woven/fleece carrier material). The cut is then re-sealed. The cleanest (and absolutely invisible) method for smaller air bubbles is injecting glue under the wallpaper with the glue syringe.
Another reason for lumps under the wallpaper is a visible excess of wallpapering paste. If the paste cannot be smoothed out, the glue syringe can do wonders. The hollow needle pierces the blister and the glue is extracted into the barrel by pulling the plunger. Any remnants of the adhesive are carefully smoothed towards the puncture mark with a clean, lint-free cloth or a piece of kitchen paper.
Models of glue syringes
In terms of appearance, components and function, a glue syringe is very similar to general medical syringes. The main differences are the external diameter, the length and the material of the cannula.
Glue syringes consist of a cylindrical plastic case, a plastic plunger (with or without rubber stopper) and a cannula (hollow needle) which is attached to the tip of the case. The hollow needle makes it possible to inject or extract liquids without having to pull the wallpaper off first. The plunger is used to draw the adhesive into the syringe, and to eject/inject it.
Glue syringes come in hold capacities between 10 and 60 millilitres. For DIY purposes, a syringe with a 20 millilitre capacity is usually sufficient to get rid of bubbles and lumps. A measuring scale is printed in black on the syringe. The case and plunger are usually made from transparent plastic, but the plunger is sometimes coloured.
Cannulas are either metal or plastic. Metal cannulas are preferable as they can be used for any wallpaper type, surface material, structure and thickness and are universally suitable for all wallpapering purposes. Plastic cannulas can break if the wallpaper material is too thick or coated. The external diameter of the cannulas is between 0.9 and 1 mm, the length up to 70 mm. To protect the hollow needle (and your fingers!), most glue syringes come with a transparent cap that is placed on the cannula. Prices for glue syringes start at around £2 - a small investment you won't regret.
Glue syringes are suitable for any wallpaper adhesive or paste. Although similar to disposable medical syringes, the glue variety can be used repeatedly, just as long as all components are cleaned and dried thoroughly after use.
Can I use any disposable syringe for wallpapering purposes?
Disposable syringes are used in many areas, for instance medicine, feed dosage in animal husbandry and breeding, or in gastronomy for marinating. But they are also immensely useful for DIY or hobby projects. One syringe looks much like the next, the main differences being sterility, length and diameter of the cannulas, depending what area they are used for. For medical use, the syringes need to be sterile. The length and external diameter of the cannula depends on the type of liquid that is to be injected. For jelly-like consistencies, like wallpaper adhesive, the cannula opening has to be wide enough to let the substance flow through easily. The hollow needle should be neither too long nor too short. As a general rule, any disposable syringe can be used as a glue syringe, as long as the cannula is wide enough to let the wallpapering adhesive through.
Correct handling of glue syringes (or disposable syringes)
If you need to puncture a wallpaper bubble and fill it with adhesive, follow these easy steps:
- Drawing the adhesive into the barrel: The plunger has to be pushed all the way down the barrel. Put the cannula into the adhesive and carefully pull the plunger until the required amount of adhesive has been extracted.
- Now put the hollow needle at a slight angle directly into the centre of the bubble, and puncture it.
- Push the plunger down to inject the adhesive from the barrel via the cannula under the wallpaper. Work carefully to avoid excess adhesive emerging from the puncture mark. As long as you can't feel any resistance, push the hollow needle under the wallpaper as far as it will go.
- Spread the adhesive around the area of the bubble and gently smooth the wallpaper towards the puncture mark; remove excess glue with a piece of kitchen paper.
Larger bubbles might have to be punctured in more than one place to effectively spread the adhesive across all dry areas. Important information regarding paper-based wallpapers: Once the adhesive has been spread, observe the instructions regarding soaking times and then carefully smooth the bubble towards the puncture mark.