# My built-up finishes



## Mike Jones (May 1, 2014)

Built-up finishes, as the name implies, are simply finishes that are built up layer upon layer, or coat after coat. Any of the “film” finishes can be used, e.g., shellac, varnish or lacquer. I will discuss lacquer and wipe-on oil/varnish here because I believe that it is the easiest for the hobbyist, and requires the least amount of equipment.

There are no “secret” formulas, no specialized equipment, nor even any expensive brands required. Quality sandpaper might be considered the only exception. I recommend Finkat* or Kovax* (Eagle) brand aluminum oxide sheet paper in grits from 220 to 800. The most important requirements are patience and willingness to do a lot of hand sanding. There are no “shortcuts”, but there are methods and practices that will make the work go with efficiency. ( What? Did I lose you already?)

A fine finish is achieved by a process of ever refining (leveling)a surface. And leveling is a process of ever finer degrees of cut and fill. We all know that wetting the surface of wood will make grain color and contrast “pop” but, at the same time, clear finishes will show defects or flaws on the surface. So, applying layer after layer of clear finish alone will not hide flaws so much as it will magnify them. In other words, your bare wood surface must be nicely prepared.

Assume here that your wood has been properly prepared for finish by filling large cracks, voids, worm holes, etc., with your choice of fillers sanded smooth and leveled through 400 grit. I begin many projects with a lacquer sanding sealer and I use Deft* Sanding Sealer because I can buy it locally at most paint stores and many hardware stores. I have used other brands and find them to be equal in most respects. Ask for lacquer based nitrocellulose sanding sealer if you don’t find Deft*.

The application of sanding sealer is “mopped” on with rag, sponge, or brush, and because it dries very quickly, I want to keep my project mopped wet with the sealer until it begins to get sticky and drags. Often, some areas of the surface will suck up more sealer than other areas and what I want to do is to keep the fast-drying areas wet with more product, but I’ll wipe down the areas where it is not being absorbed with paper towels.

Ready to sand in half an hour or so, this is the time to really, really examine the work piece for surface defects. You will be able to see, once coated, the little things, the torn grain, raised grain, the bruised wood, etc., that you could not see when dry. Once you have applied your first coat of sanding sealer, you are already done with all power sanding as the heat from the spinning disc will melt the lacquer and clog your paper. But this is the time, with just a single coat of sanding sealer, to correct all problems with the surface of the wood that can be corrected.

Sanding dried lacquer will produce a fine white sanding flour, ( if not, and making granules, or if clogging your paper, it is not dry enough to sand) and this flour will get deposited in open pores and hairline cracks. That white flour must be blown out or you will have white spots under your finish. Clean the surface well after each coat is sanded before proceeding to the next. Repeat the “mop-on, sand down” ….”mop-on, sand down” several times. You are sanding dry with 600 grit, and the sanded surface will appear a uniform, dull, off-white appearance. Look closely after wiping the sanding dust away for shiny spots. These spots are shiny because the sandpaper has skipped over the top of them, indicating low spots (not level with the surrounding surface.) Continue with the “mop-on, sand down” until the entire piece is uniformly dull from the sanding and there are no more low spots. This process cuts high spots with sandpaper, and fills low spots with sanding sealer..

At this point, when the entire surface is level, you could go directly to buffing. ( I like to rub the piece with 0000 steel wool first, as the buffing will go faster). The Bealle system of tripoli wheel followed by white diamond wheel, followed by the carnuba wax wheel will work, but I have come to prefer skipping the tripoli and white diamond and going from steel wool to Don Pencil;’s PL compound and wheel. The buffing wheels and compounds will level the sanding scratches and your piece will shine up beautifully. Following that polishing, one more step in leveling is called for: the carnuba wax wheel.
Wax levels the surface even more and at a microscopic level, filling even the microscopic swirls left by the polishing wheel…. and you cant get any better than that.

Well, that was easy enough wasn’t it? The bad news is that, neither the sanding sealer nor the wax is very durable and the deep shine will only last for a couple of years. Just as with your furniture or cabinets, the shine can be restored with a fresh polish and/or wax periodically. But, if you will be giving or selling the piece away, this will not be a good plan. This is why I top coat with a finishing lacquer or a varnish.

Wipe-on varnishes are the ticket here, and my favorite straight-from-the-can product is Waterlox* as it contains the right ingredients for durability, ease of use, and it takes polish well. There are hundreds of these products, and I am sure that many of them are excellent. I read the MSDS/TDS sheets for ingredients and look for tung oil and spar varnish, and I tend to shy away from the Polyurethanes.

Typically, I will put on 2 or 3 wipe-on topcoats. I get the piece just covered, not too thick, using a clean, lint free cloth, then smooth and spread the finish evenly with my hands and fingers. I can feel the thick and thinness this way, and I just want to apply it evenly, and then step away. Wipe-on varnishes contain enough oils to give good flow-out, so it is somewhat self leveling. They also contain a lot of solvent which promotes drying, so you can’t play with it or it will start to get tacky and then will not flow out without leaving finger prints. Give these finishes 24 hours and sand with 800 or 0000 steel wool between coats, 72 hours before final buffing.

Alternately, a method used by many wood finishers, is to wipe on the oil/varnish, wait 15 minutes and wipe it off with paper toweling leaving only a very thin film. The intention is to get a thin, uniform covering. Too heavy will result in drying problems.

(continued)

Spraying on finish allows for building a finish faster and easier, and in my shop, I will only spray lacquers because lacquer overspray is easier to control, and I don’t have to clean the gun after every spray session. In my nanny state, I cannot buy a finishing lacquer made for spray application. And, manufacturers of these products will not ship into California either. If you have the same problem, you can spray Deft’s brushing lacquers (sold just about every where and online) and they are of very good quality. Brushing lacquers contain retarding ingredients which slow the drying and consequently they require a longer wait time between coats. Read the label and don’t be tempted to push it.

Spraying brushing lacquers, however (because of the retarders), rather defeats one of the advantages of lacquer finishes. I have resorted to purchasing my spray application finish lacquer from out of state paint stores and I have simply asked for “water clear, high build, nitrocellulose finishing lacquer”. Typically, there are 2 grades of these lacquers: one is an economy blend used for interior trim and doors (architectural), the other, a premium blend, is made for fine furniture. The premium blend is non-yellowing, and it is the one that you want.


The procedure for lacquer top coats is essentially the same as the ‘mop-on, sand down’ procedure, except now you will “spray-on, sand down”. Because the sprayed on surface does not leave brush marks, or mop marks, the sanding part goes quickly. Sand at 600 dry, looking closely for tiny shiny spots to sand out, then repeat. I spray a very thin coat…just until the surface looks wet, then wait 10 to 15 minutes and spray another thin coat, and then after another 10-15 minutes, a third thin coat.. I give this application 2 or 3 hours to dry, then sand at 600. and repeat with at least two more applications done the same way. Lightly sand the last top coat after 24 hours, and buff as before.

Shiny is easy. Depth takes time. It is depth, more than anything else, I think, that sets my finishes apart. And, while it might seem excessive, the buffing and waxing somehow improves the appearance of any top coat that I have ever used.

Gloss sells, or so the consensus seems to be, but there are times when “satin”, “matte”: or semi-gloss is called for. To achieve these less-than-glossy top coats, I use the same gloss lacquer and the same procedure as described above (eliminating the buffing) then cut it back. Cutting back with 0000 steel wool will produce a matte finish. To move up to “satin”, I would rub with pumice, up another notch, a rub with rottenstone. I have also used rubbing compounds from the automotive section of the paint store. Any and all of these will produce pleasing, hand-rubbed looks to a built up finish.

Well, that’s how I do it. I hope that something here will help you to get a satisfying finish. You should know that it can be frustrating at times, and getting to the end results that you want requires more of a mental attitude than expense. If you are determined to get it, you will get it.

Reactions: Like 1 | Thank You! 4 | Great Post 4 | Informative 3 | Useful 1


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## Molokai (May 3, 2014)

Subscribed. Any photos ?


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