What does a glue roller do?
A roller let’s you spread glue evenly over your veneer substrate. The proper application of glue is essential to preventing bubbles in your finished veneered product. Used properly, this woodworking tool will help you roll out a smooth and even glue thickness that will prevent bubbles from forming in the cured veneer panel that are caused by pockets of excess glue or too little glue.
Why do I need a glue roller for veneering?
There are other ways to spread veneer glue, but using a glue roller will allow you to quickly and evenly apply glue to your substrate.
As important as cutting the veneer exactly, applying the glue properly is just as crucial. It is extremely important to apply the glue evenly, otherwise you will end up with a veneer that is not flat.
Not properly distributing the glue onto your substrate will either leave too much glue (little pockets of glue will remain underneath the veneer creating bumps in your veneer), or not enough glue (the veneer will not glue to the substrate and will create air pockets or raised bubbles).
How much glue do I put?
The general rule is that the surface of the substrate should look evenly painted with veneer glue. Think about how spilled milk looks like. This is the amount of glue that should be applied.
A good way to test is to place a pencil mark on the substrate and apply the glue. If you can barely see the pencil mark on the substrate (through the adhesive), you have the right amount of glue.
Are there different kinds of glue rollers?
There are typically two kinds of glue rollers, disposable, and non-disposable. Many woodworkers use a simple paint roller with an appropriate foam roll. It’s best to find a roll that does not absorb too much glue. It will make it easier to apply more evenly, plus you will not be wasting as much glue.
Another alternative to buying a specific glue roller is to use a piece of PVC. Cut a piece of PVC pipe to fit over the roller cage of a paint roller. The PVC pipe gives a more even and smooth application, and doesn’t soak up the glue like a paint roller would. Clean up is easier, too. Just let the glue dry on the pipe, and then chip it off. Now it’s ready to be used again. I would test this method out before hand to make sure that you are comfortable with the procedure as it ‘feels’ different than applying glue with a typical sponge roller.
Are there any other specific instructions?
Remember to always apply the glue to the substrate material, and not directly on to the veneer. The veneer will absorb the glue and start to curl almost immediately, making it almost impossible to work with.
Always have enough glue available. Sometimes it takes more glue than what you are expecting. The time it takes you to get more glue from somewhere in the workshop may make the glue up stressful, and may make it difficult to complete your veneer piece properly.