It’s too expensive.
I heard this quite a bit when I was selling lacquer in various parts of the country. The price per gallon was the first thing many customers would ask about, probably assuming that all lacquers were the same except for price.
Many of these customers eventually came to the conclusion that the value of the product was what they were really after and that only after that had been determined could cost per gallon be considered as a factor.
I also heard “I’ve been doing this for 20 years and haven’t had a complaint yet.” Given the progress that has been made in finishing equipment, tools and materials in any 20-year period since the 1940s, I believe the finisher who made that statement missed many opportunities to improve his bottom line.
Factors affecting the bottom line for a finishing business include the cost of the facility and the utilities to run it, the tools and equipment for performing the operations, administration, transportation, labor and materials consumed. The finishing materials (sandpaper, steel wool, other abrasives, glue, stains, colorants, sealers, solvents, additives, topcoats, touch-up materials, rags, masking tape, paper) represent a relatively small portion of those costs. Labor is generally a major component.
Here are some things to consider:
In 1975, I could buy a quality lacquer containing 25 percent volume solids. Remember, the solids content determines how much of a gallon of lacquer remains on the surface of your workpiece if you were able to apply it at 100 percent efficiency.
Let’s say my specification for a particular job, a triple dresser, is 2 dry mils thickness for the top, case and drawers. I’m using a high-quality conventional spray gun of the time, a Binks No. 7.
In order to spray the lacquer so that it flowed as desired, I had to reduce it by 50 percent with lacquer thinner, so I was spraying at 12.5 percent. Applying this at a wet film thickness of 3 mils will give me about .375 mils of dry film. Achieving my target of 2 mils will require more than five coats. If I do any significant sanding between coats, the total film build will be reduced, so I might need six or more coats to allow for the reduction.
If I used a gallon of lacquer at $30 (this example uses approximate 2013 prices for comparison purposes), half gallon of sealer ($15), half gallon of reducer ($10), quart of dye stain ($17), pint of pigmented wiping stain ($9), half pint of glaze ($4) and assorted shop supplies ($15), I’m out $100. Plus, it would take about 5-1/2 hours to complete the job.
Four decades later
Today, I’m using an HVLP or air-assisted airless application system for greater transfer efficiency and a modern precatalyzed lacquer at 25 percent volume solids. Since the material is supplied as ready to use or ready to spray, no reduction is needed if I spray at the specified temperature and my gun is properly set up for that coating. Even with the old gun, just the upgrade in lacquer allows me to apply the same wet film thickness (3 mils) resulting in .75 mils dry per coat. Now only 2.66 coats are required to achieve 2 dry mils.
Three coats instead of six will allow for sanding between coats. I’ve only used a half-gallon of lacquer and no reducer. I’ve saved 45 minutes in setup, cleanup and application time and, if I am sanding between coats, another 30 minutes. There are other incremental savings on tack cloth, sandpaper, energy for air movement and electricity for the compressor, etc.
I can expect 40 percent transfer efficiency from a conventional gun, 65 percent from a HVLP and 80 percent from an air-assisted airless. These percentages assume ideal conditions since transfer efficiency is also affected by the shape of the parts and the finisher’s training and skill. But the point is that simply moving from conventional to air-assisted airless would cut my material usage for lacquer and sealer in half.
Many of today’s coatings can be applied to a greater film thickness per coat than lacquers of the past, so further reduction in the number of coats can be realized. In the example, I used 3 mils for the film thickness that was typical for lacquers in the 1970s. Today I would spray the precat at 5 mils for the horizontal surfaces. Many self-taught spray operators have a tendency to apply very thin coats to avoid runs or curtaining. Developing the ability to spray a full wet coat confidently is crucial to efficient application.
Read the literature
Manufacturers have recommendations concerning the optimum build to offer the protection expected. Too much film build can result in a brittle finish, prone to crazing or wrinkling. The product data sheet or tech sheet will show the target viscosity, generally at 77 degrees. Measuring and recording the viscosity and temperature of your coating will help ensure that you are spraying within the parameters established by the manufacturer. Spraying the material too cold will result in poor atomization and flow out. Correcting that with reducer or retarder makes the material more susceptible to runs and curtaining and reduces the solids content.
Use a wet mil gauge to measure wet film thickness. You might be surprised at how much or how little you are applying in each coat. You can calculate the dry mil thickness by multiplying the wet mil thickness by the percent of volume solids (4 wet mils x 25 percent volume solids = 1 dry mil). Adjust your spray technique or the fluid pressure/tip size to achieve the desired wet millage.
The sheet might suggest tip and needle sizes, as well as air and fluid pressures. Use them as a starting point. It’s a better approach than adjusting the coating to your application system. And it’s advisable to purchase coatings as a system, using all components from the same manufacturer to ensure compatibility.
In the end, the price per gallon is not the metric you need to use, but the cost of the film deposited on the work or the cost of the applied solids. Often a higher cost per gallon, for the right material, can contribute to a lower-cost finished product.
This article originally appeared in the December 2013 issue.