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Newsletter #148

To improve is to change; to be perfect is to change often.

                                                                                        — Winston Churchill

I thought it would fun last month to become less anonymous and write a bit about my personal history and how I ended up involved with Apollo and HVLP technology. Quite a lot of readers must have thought so too, which became quite apparent with the e-mails I received when the April Newsletter was posted. Many thanks for all of the kind words and comments. They are all much appreciated.

This month we welcome back Scott Burt who offers his unique take on how to be a better finisher. I always enjoy reading his articles as it always adds to my own perspective on the subject. I am fortunate to see our writer’s articles prior to their publication in our newsletter and I must admit often it stimulates my thought on what I want to share with all of you.

I’ve come to know and understand that nothing is fixed and written in stone when it comes to finishing. Equipment gets modified and changed, as does the formulation of many of the products we use. When results change, we need to find out why. Scott talks about this and more in his article. Much of Scott’s experience revolves around wood and wood finishing. I would have to say that it has been the same for me.

Now, as Apollo HVLP Turbospray expands into the automotive marketplace, I am back to the learning stages as far as automotive spray technique, specialized paints and the needs of the automotive after market. While much that I have already learned over the past 35+ years about spray finishing and coatings is applicable, I’m finding a whole new world and realize that Scott’s words are so important.

We all want our projects to look their best and being a student of finishing, much as we are students on how to build our project, is just another part of becoming a better craftsperson.

As always, enjoy our knowledgeable and talented writers. Speaking about talented writers, next month we will be featuring an article by one of our readers. He has a particular technique he will share with us.

In the future, if you like to write and you have a particular passion that is unique that you would like to share with our readers, please let me know. If it is timely and we can use it, I will be happy to share it with all of our newsletter readers in a future issue.

bill boxer signature
Bill Boxer 
Sr. Vice President and COO
Apollo Sprayers International, Inc.
[email protected] 

Product of the Month: Bloxygen

How many times have you seen leftover paint, stain, or varnish skin over, thicken, or solidify? How much time have you spent peeling or filtering? How many projects were ruined during finishing because of particle contamination or chemistry changes? For years we have all struggled with this problem…now there is a solution, a powerful natural chemical preservative that’s safe and easy to use.

It’s called BLOXYGEN (blocks-a-jen), short for “blocks oxygen.” Using an effective but safe gas, BLOXYGEN will allow you to store leftover finishes as long as you want. BLOXYGEN works by keeping air and moisture away from products that react with our environment: varnish, stain, paint, polyurethane, glues, inks, etc. Anything harmed in the presence of oxygen or moisture will be saved when stored with BLOXYGEN.

How does it work? BLOXYGEN uses an ultra pure gas, collected from our air. While safe and natural, it is also extremely powerful as a preservatives. WOOD magazine gave it five stars for performance, five stars for value and their editor’s choice award!

Finishing Feature Article by Scott Burt: Watch Yourself

Usually that phrase is a warning. It can also be a really good idea.

In recent articles, I have written about the importance of eliminating bad habits in your finish program and how to replace them with better ones that are duplicable. But, how do you really know HOW you are doing? The proof is not always totally in the pudding, the finish. Sometimes you can end up with a good finish in spite of a horrible experience getting there, solely on the virtue of good gear and materials. The products can be better than you. Ideally, you want to be in charge of your finishing destiny.

We take those lucky days and run – gifts from the Finishing Gods. Personally, I would rather have a slight flaw in a finish where everything went right. I’m not so sure it is better to be lucky than to be good in the long run. Most of us prefer to be good, it is more predictable.

Observation

Most of the best finishers I have ever known are students of the game…always engaged in learning. One of the best ways that we learn new skills (or improve on existing ones) is by either doing them ourselves, or observing others in the act of doing them.

That certainly holds true for improving in sprayed finishes READ MORE

 

Finishing Tip by Bob Flexner: How Sheen Works

The sheen of a finish is measured as the reflectivity of the dried film – that is, the sharpness of an image reflected in the surface. Sheens vary from high gloss to very flat. The contrast between gloss and satin sheens is shown in the accompanying picture.gloss-and-satin-sheens.jpg

Finishes are supplied in various sheens, determined by how much flatting agent, which is usually silica, is added. These are usually identified with names such as gloss, semi-gloss, satin, matte, eggshell and flat. The names reflect the manufacturer’s interpretation and are often chosen for marketing purposes, so the actual sheens you get can vary noticeably among brands.

A more exact, and better, method of identification uses a numbering system from gloss (90 sheen) to flat (10 sheen). Some manufacturers, especially those targeting the professional market, use this system.

You can create your own customized sheen by mixing two sheens of a given finish type together, or by letting the flatting agent in one container settle, then pour off the top half into another container and mix the two parts.

To see what you have, you have to apply at least two coats. After sanding the first coat smooth, apply the second and let it dry. This will give you the accurate sheen.

The final sheen is established by the sheen of the last coat applied, not by an accumulation of sheens of all coats. So you can change the sheen on any surface simply by applying another coat with the desired sheen.

Sheen can also be achieved by rubbing the last coat with abrasives. The last abrasive used will establish the sheen, so you could go from satin to gloss, then back to satin and back to gloss. Once you begin rubbing with abrasives, the flatting-agent-created sheen of the finish you’re rubbing is no longer a factor. Satin can be rubbed to gloss, and gloss can be rubbed to satin.

The downside of a rubbed sheen is that it shows scratches more easily than a sheen created with flatting agents. Any light abrasion running across the ridges of the rubbed scratches flattens them and appears as a shallow scratch.

 

Finishing Tip by Bob Flexner: Dating Furniture by the Finish Used

Because different finishes have been used at different times, it’s often possible to date furniture simply by the finish on it.

In the 18th century and earlier, makers used whatever finish they had available, usually wax or linseed oil. If the maker lived near a port city, alcohol- or turpentine-soluble resins may have been available.

By the 1820s, transportation had improved and shellac flakes, along with other alcohol-soluble resins, became widely available. Alcohol evaporates rapidly so these finishes dry fast and don’t collect dust. As a result, shellac became the overwhelmingly dominant finish used on almost all furniture and woodwork for the next 100 years.

In the 1920s nitrocellulose lacquer became available and slowly replaced shellac as the favored finish. There were two primary reasons. First, shellac is a commodity product, so the higher the demand the higher the price. Second, in contrast to the single alcohol solvent required for shellac, lacquer thinner is a blend of many solvents with varying evaporation rates, so lacquer thinner can be adjusted so the lacquer dries at a normal rate in widely varying weather conditions.

By the 1960s, a number of additional resins had been developed, which began replacing lacquer. These include primarily very durable catalyzed, polyester and UV-cured finishes. In the amateur market, polyurethane varnish largely replaced alkyd varnish.

In the 1980s and 90s, water-based finishes were introduced to address the growing demand to reduce VOCs in coatings.

With this historical knowledge, and assuming you’re dealing with an original (not refinished) finish, you can fairly accurately establish the period during which the furniture was made by testing with various solvents using a process of elimination.

Wax dissolves in mineral spirits (paint thinner), naphtha and turpentine.

Shellac dissolves in alcohol. Lacquer dissolves in lacquer thinner.

Water-based finish becomes soft and tacky in lacquer thinner, toluene and xylene.dabbing-with-alcohol-to-establish-a-shellac-finish.jpg

Using one or more of these solvents, dab a little onto an inconspicuous area as shown in the accompanying picture of using denatured alcohol to test for shellac, and see what happens. If nothing happens with any of these solvents, the finish is varnish or one of the newer more-solvent-resistant finishes.

 

Finishing Tip by Bob Flexner: How to Choose a Sandpaper Grit

Sandpaper grits vary from very coarse to very fine. How do you choose which grit to use for any given situation?

The answer is actually quite simple. In all cases you are using the sandpaper to remove a problem. So choose a grit that removes that problem efficiently without creating larger than necessary scratches that then have to be sanded out.

For example, you would choose a coarser-grit sandpaper (#80 or #100) to remove severe washboarding caused by a jointer or planer but a finer grit (#120 or #150) on pre-sanded, veneered plywood or MDF. And you would begin sanding with an even finer grit (#180 or #220) if you were just checking to make sure your stripper had removed all the old finish from a refinishing project.

Likewise, you would choose a coarser-grit sandpaper (#220 or #320) to sand out brush marks in a finish but a finer-grit (#400 or #600) to remove fine dust nibs or mild orange peel.

In all cases remove coarser-grit scratches with finer grits until you reach the grit you want to end with. You can skip grits, but this will require that you sand a little longer with each grit than if you don’t skip grits.

These rules apply whether you’re sanding by hand, sanding with a pad or random-orbit sander, or sanding with a stationary sanding machine.