Preparing Wood for Finishing
Preparing Wood for Finishing
Preparing wood before trying to finishing it is very important. A perfect finish will be destroyed by wood that is not read for the finish By avoid the pitfalls before you begin, you can avoid the work it will take to correct the finish that does not come out as you had planned.
Generally speaking, I don’t like finish to get on any mating glue surfaces. Using an adhesive like epoxy could certainly work, but for the sake of nice tight joints and a good wood to wood bond, I prefer to leave the joints with no finish at all, even if that means trickier finishing later. A perfect finish is meaningless if the piece falls apart.
The reason you have to sand wood before applying a finish is to remove machine marks. All machine tools leave cuts or impressions in wood that are highlighted by stains and finishes, especially by stains. Before machine tools appeared in the mid-nineteenth century no sanding was needed. Indeed, there was no sandpaper. Wood was smoothed with hand planes and scrapers. You can still use hand planes and scrapers to smooth wood; you don’t have to use sandpaper. You can hand plane or scrape the wood straight from the saw, or you can begin the smoothing with a jointer and planer and then finish off with a hand plane or scraper. You can also use molding planes and scratch stocks to shape wood rather than routers and shapers.
Make the wood as smooth and perfect as possible to ensure a great finish. Find and fill defects, conceal unsightly edges in plywood, and sand thoroughly. Do all prefinish sanding with orange-colored, open-coat garnet sandpaper. Dust won't clog it as easily as closed-coat papers, so it lasts longer and works better. For hand-sanding, "A" weight paper works best. Wrap it around a sanding block so the surface you're working on remains flat as you smooth it. The higher the grit number, the finer the grit. For most work, start with 100-grit, then use 150-, and end with 220-grit. Clean the surface of the wood between sanding with a vacuum, a tack cloth, or a paper towel lightly dampened with a solvent such as lacquer thinner.
Wood finishing is fun and easy. Don't rush through finishing a piece of furniture as if it is a race. Imagine how it will look finished in your home in living color. Set up a good prep area. Turn on some tunes. Get creative and enjoy the journey. Make something that will bring beauty to your life, save you money, and have fun in the process. Take an a little extra time to get a good result. If you are an experienced wood finisher, refer to our retail brochures for quick and simple finishing instructions. For those of you that like to know more, we'll take you step-by-step through the wood finishing process including preparing the wood, selecting the finish and applying traditional or decorative finishes. Whether you're planning to finish furniture for your own home, make gift items, or take up woodworking as a hobby, you'll find wood finishing to be a rewarding experience.
The confusing answer to your question is, it depends. As a general rule of thumb, I pre-finish whenever it will be difficult or tedious to finish after assembly. For instance, the inside of a small cabinet or any place where three planes meet. Think of a bookcase where a shelf meets the side and the back. An area like that is a royal pain to finish.
There are two primary methods of smoothing the wood to accept the finish: scraping and sanding. Sanding is the simplest and the one the majority of woodworkers are most familiar with. Scraping, however, takes some practice, and in many cases, a combination of both scraping and sanding is the best.
Bubbles can come from a few different sources. One can be the wood itself. The pores and pockets on the surface of open pored woods like oak and ash can sometimes trap air, which wants to bubble out after you coat it with finish. You can also introduce air into the finish if there is a lot of air in your brush.
I too occasionally wipe down my pieces before finishing instead of just blowing off the dust. In just about every way, wiping down is the better method. Blowing the dust off can actually damage the wood if the stream of air is too close to the surface. And not to mention, when you blow the dust off, where does it go? Into the air and back down into your finish.
Finishing woodwork projects can be one of the most frustrating things for most woodworkers. In and effort to find something that is easy to apply and is little affected by the dust in your workshop ... we present Jesse's formula, which by the way isn't really a secret, but once you have tried this technique, consider yourself a member of the Pro Finishers. Its easy to apply and looks fabulous, we think even you will be amazed.