Spot finishing can be win-win situation

Finishers are generally familiar with blushing in lacquer, a cloudy white appearance in a lacquer coating caused by a reaction with moisture. What many don’t know, however, is that water and alcohol spots or rings are chemically identical to blushing, and can be removed the same way. Even the marks left by a hot pizza box placed on the conference table can be treated similarly.

Photo A is an example of the effect of a wine spill, caught too late to wipe it up, on an Ethan Allen maple trestle table. The table was made in the early to middle ’70s, and has a “straight” or uncatalyzed lacquer coating on it. It has been polished with emulsified oil polishes not containing any wax and used occasionally for dinner parties, but hasn’t seen daily use.

The first step in removing this spot is to test the finish in an out-of-the-way area, such as the inside upper portion of the trestle. Spray a small wet spot of a blush eliminator, called by a variety of names such as no-blush or blush eraser, onto the trestle and observe it for a minute. We’re looking for bubbling, cracking, crazing, checking, or lifting (Photo B). Rub the spot with a finger. If it is sticky, but has not exhibited any other behaviors as described above, it is a lacquer, and this technique should work.

If nothing at all happens, and the coating is not softened, the trick will not likely work, nor would you perform the technique if the coating did deform as described.

The next step is to make sure the area to be treated is perfectly clean and free of any wax, oil or silicone by cleaning with a wax remover.

Apply blush eliminator
After cleaning and wiping the area dry, you are ready to apply the blush eliminator. Make sure the coating and blush eliminator are at, or above, room temperature (a minimum of 70 degrees F). Put cloth or paper on the part of the table you do not wish to get overspray on, and move other furniture away from the table. Spray lightly on the affected spot, observing what is happening. If the spot does not disappear in 30 seconds, spray a bit more, but do not get the surface very wet. A solvent is dissolving the coating, and slowing down the drying, allowing the moisture to escape and the resin to form a clear film, free of the cloudiness caused by the moisture/resin reaction.

Any overspray that falls off the table will evaporate harmlessly before it reaches the floor, and any overspray that falls on the finish around the area to be repaired will only momentarily soften that finish before drying. Now allow the area to dry thoroughly — several hours, at least. The drying process can be hastened with careful use of a heat gun or hair dryer. When the lacquer has sufficiently hardened, rub out the finish with an emulsified oil polish to act as a lubricant and a good grade of 4/0 steel wool (Photo C).

For a high-gloss finish, you might have to use several different grades of abrasive polishing compounds to bring the sheen back to match the original finish.

Most coatings for mass-produced furniture are applied “off-the-gun.” They are sprayed on and allowed to dry, and are not sanded to level them further, or polished with an abrasive to either raise or lower the sheen. They can be identified by the slight texture and the absence of fine scratches in the direction of the grain left by steel wool or another abrasive.

When using the blush eliminator on an off-the-gun finish, you generally will not rub with any abrasive, but will simply leave the no-blush to dry thoroughly, then apply a polish or wax to give an even sheen over the surface.

For the lower sheens that are popular today, the no-blush might cause the spot to become somewhat shinier, or higher in sheen, than the original. In this case, you can use Mohawk’s No Blush Blender Flat.

In contrast to the “off-the-gun” finish, a rubbed finish was sprayed on and dried or cured, then sanded to remove surface irregularities and to level it more thoroughly. For a high-gloss look, the coating was sanded with successively finer grits to bring the sheen up, and then polished with very fine abrasive compounds, either paste or liquid.

For a lower sheen rubbed look (as in the example in this article), the coating was applied, dried, sanded level, and then rubbed with a fine (4/0) steel wool with a rubbing lubricant. This gave a high-satin sheen to the table, matching the original look (Photo D).

A real moneymaker
Removing water stains is a real moneymaker for the on-site technician. The problem is common and unsightly. It is unlikely to happen on coatings that are not lacquer, and therefore the procedure for removing the mark is likely to work. If the coating is heavily waxed, often the operation of removing the wax also removes the mark. The blush eliminator products are the most valuable aerosol products a finisher or repair technician can have.

This repair, or defect remediation, is one example of the value of field touch-up. This type of spot finishing is a great way for some finishing technicians or businesses to increase their income, and reduce expenses, as compared to bringing the item into the shop. The working environment is provided by the customer, and the cost of transportation is included in the price for the service call. The customer is not without the use of the piece for an extended period of time, and is spared concern about the piece while it is in other hands.

Manufacturers of touch-up products such as the blush eliminators often offer training classes to teach the use of their products and procedures as well as instructional DVDs.

Greg Williams is the Sales and Technical Advisor for H. Behlen and Senior Instructor for Mohawk Finishing Products.

This article originally appeared in the December 2008 issue.