The first question you ask yourself when you are looking for a finish is, how many coats need to be applied and how well will it protect my project? Wipe on finishes fall into two categories, those that are simply a wipe on oil, such as a boiled linseed, and those that are basically just a thinned varnish base, or in some cases a combination of both.
If you already have a wipe on finish and aren't sure exactly what you have ... here is how to test it. Pour a small puddle of it on hard surface, preferably glass. Let it dry for a few days and have a look at it. If it dries hard and smooth ... it's varnish based. If it dries like it has skin on it this will be a vanish oil blend. Its important to know this ahead of time so you know how well the finish will protect your project. A varnish based will protect the best because it is harder than the oil/varnish blends.
OK, so the diluted varnish wipe on finishes give a better protection, why would anyone what an oil/varnish blend wipe on? ... Good question ... and the answer is, looks. On some woods a deeper richer look will be achieved by using products that have more oils in them. Oils tend to penetrate the wood deeper, therefore making the grain richer and more three dimensional. This is especially true for some of the highly figured woods. Often these pieces "come alive' when a oil based finishes are applied, but ... donâ't forget the protection of the wood is far less too.
There are a few things to know about wipe on finishes. First of all they will not rescue a poorly made project. By this I mean you still need to do the pre work on the wood. No finish in the world is going to be good if it's going on a project that has not been sanded and prepared properly. Depending on the wood you are using you should be finishing the entire project with something link a 320 - 400 grit. Yup ... I know ... there is still no substitute for sanding.
The second point is that after each coat the wood needs to be sanded "LIGHTLY" after each coat has dried and before the next application. Not performing this step will nullify all your hard work so do not pass over this step. The rest of the items are common sense ... use a nice clean, lint free rag, and above all DISPOSE OF YOUR RAGS SAFELY ... that is, in a metal, fireproof container, or soaked in water. It takes very little for internal combustion of varnish, solvents and oils to combust and cause a fire, so pay close attention to this ... I CANNOT emphasize this enough.
If you really want to have some fun and custom make your own wipe on finishes ... here's how. Purchase a can of oil-based varnish, and some paint thinner or mineral spirits. The formula is four parts varnish to one part thinner, or for a thinner product mix one part thinner to three parts varnish. Here's another tip, if you want it to dry quicker a few drops of "japan drier" per pint will accomplish this ... careful about doing this in hot dry weather when it's already drying quick, or if you are coating a large surface. Follow these few tips and you too can join the ranks of the professional finisher.
Copyright Colin Knecht