Don’t be gun-shy about learning to spray coatings

There’s a certain amount of resistance among amateur finishers — or woodworkers who don’t do large volumes of finished work — to use spray application equipment. As an outside salesman who traveled large parts of the country selling to both large factories and one-man shops, it was to my customer’s advantage and to my own to be able to help them become more efficient and produce higher quality goods.

The smaller shops provided me with lots of reasons for doing things the way they did, from “this is how my daddy did it,” to “it lasts longer if you rub it on,” or “my customers like it this way.” This last one was from a finisher that used one pigmented stain for everything he did, regardless of wood or style, new wood, old wood, refinishing or antique restoration because “it’s the best color ever made.” Seldom would they admit that it had anything to do with the perceived cost of equipment or material, and even more seldom that they simply did not know how to do any better.

The bottom line was that finishers tended to stick to what worked for them and, to justify their resistance to change, by averring that “I’ve never had a complaint,” ignoring the possibility of doing more, better and faster just by learning and risking a little.

A number of factors have changed that picture through the years, including the Internet, woodworking groups who share knowledge more freely, books, tapes, DVDs, woodworking shows and finishing classes given by suppliers.

There are plenty of woodworkers, both amateur and professional, who are becoming more sophisticated and knowledgeable about finishing and many more who would like to become better, but are intimidated by the continued perceptions that:

• You need expensive and difficult-to-maintain equipment

• You need a dedicated area in which to spray coatings

• It is difficult to learn the techniques to spray effectively

• The materials are more dangerous (flammable, poisonous, injurious to the environment)

I’m not going to tell you here how to do it; you will find many other articles on how to perform common (and not-so-common) procedures in these pages and in several very good books readily available. What I’d like you to do is to consider with an open mind whether spray finishing is something that you can have fun with, improve the quality of your work or add value to your work.

I’m assuming you know the purpose of finishing wood. Essentially, it is to protect it and enhance its appearance. Whether you use wax, oil, varnish, shellac, lacquer or any of the more modern coating products, your goal is to create and/or preserve a look, feel and utility of a wooden item. A secondary goal in selecting a finishing product and procedure is to achieve that primary goal with the least work, the greatest pleasure or some combination of those.

We’ve got several choices about how we move a liquid coating from the can to the wood — from pouring, wiping, brushing, rubbing and even holding a wetted cloth against a piece turning on a lathe. After the coating is dry, most of these can be made to look and feel very similar with a bit more work, such as sanding, rubbing out or polishing. However, for the small lot finisher, a hand-spray application can move the liquid from the can to the wood faster, more evenly and, in many cases, more efficiently than the other methods.

With more sophisticated, multistep finishing schedules, the advantages of spray application are even more compelling. When spraying modern fast-dry coatings, recoat intervals are greatly reduced, as is the dry time necessary to prevent airborne dust and debris from sticking to the film, the time that vapors remain present in the area, the time that a piece must dry before being handled, moved or stacked and, ultimately, the total time spent finishing.

The equipment

If you are attracted to the idea of spraying some of your finishes, you will have to look at spray application equipment. Fortunately, not only are there advancements in technology that can make this easier, more efficient and safer, but less expensive equipment that will do a good job is readily available from commonplace suppliers.

HVLP (high volume, low pressure) sprayers have become the standard for the small shop or individual craftsman for several good reasons. If you do not already have a high-capacity compressor, you can get a small self-contained unit that consists of the spray gun itself and what is essentially a vacuum cleaner motor driving a turbine to provide a lot of air at low pressure, to atomize and propel the coating droplets at a lower velocity from the gun to the wood, thus greatly lessening the amount of overspray compared to a conventional spray gun. Less overspray means more efficiency, less cleanup and eliminating the cloud of airborne coating particles that has scared away many would-be spray operators in a home environment.

If you do have an adequate compressor, there are conversion guns that take the higher pressure air from the compressor and convert it to the higher volume and lower pressure (less than 10 psi at the air cap) for the conversion gun. Gravity-feed guns are popular and are easier to clean than more complicated setups.

The spray area

While a well-designed spray booth is a must for a good full-time finishing operation, simply placing a fan facing the open garage door can provide a safe and efficient fair-weather spray booth. Even in inclement weather, for spraying smaller items, you can warm up the work, the material and the air in the garage, then open the door, turn on the fan, spray the item, turn off the fan when the dust clears, close the door and go in for supper. Very fast-drying coating materials make it easier to spray outside, as the coating can dry free of dust in minutes.

Training

The basics of spray application are pretty simple and you can get a number of good books and DVDs to help. Woodworking clubs and the specialty woodworking retailers are providing more training, which can be a great way to spend a Saturday morning, and an opportunity to meet people with a common interest in finishing, enhancing the learning experience well beyond the classroom.

Safety and environment

Waterborne versions of many of the solvent-based lacquers are becoming better and more popular, reducing much of the fear of flammability, safety and environmental concerns and solvent-borne products in lower VOC versions are more available. Simple spray enclosures can be built at home by enterprising craftsmen who will take the time to understand the requirements. (Blow the spray away from your face, have the air movement from the rear, protect your respiration, wear gloves and goggles as appropriate.)

There are many good reasons to learn spray coatings. It is fast, versatile and fun. The time you spend learning the basics will pay off quickly in quality of the final result.

Greg Williams, formerly senior touchup and finishing instructor for Mohawk Finishing Products, is now a freelance instructor and consultant for finishing and touchup. He can be reached at gregalwil@yahoo.com.

This article originally appeared in the February 2013 issue.