Allegro Piano pages


Stripping and Refinishing Your Own Piano
for the Brave, Daring, or Positively Stupid

Keith T. Comparetto,
Piano Tuner-Technician
 

Your piano is both a musical instrument, and a piece of furniture. Most older instruments were manufactured by skilled craftsmen using high grade materials, and assuming it is in solid condition, it is well worth your while to refinish its cabinet. The following advice is given for those individuals who are willing to stare the odds in the face and follow through on a project that the naysayers say they could never accomplish.

Materials Needed
The non-household items are available in most hardware stores.):

  • 1 gal. 5F5 or comparable methylene choloride paint & varnish remover (5F5 is in a square light blue can; other brands are OK if the main ingredient is the same).
  • 1 qt. lacquer thinner (may also be called “epoxy thinner”)
  • 1 qt. denatured alcohol (may be called “solvent alcohol” or “shellac thinner”)
  • 1 pkg. green stripping pads, 3M or equivalent, medium or fine coarseness
  • 2 putty knives, approx. 1-1/2” and 4” in width
  • (optional) 2 narrow scrapers, one pointed and one with rounded tip for scraping inside curves or carvings. You may use two cheap potato knives and file or grind the tip of one for this purpose.
  • 3 or 4 old coffee cans (lids not necessary but helpful when the can is full of goop.)
  • 2 cheap bristle paintbrushes for applying stripper, approx. 1” and 3” in width
  • refinishing gloves for hand protection
  • plenty of old newspapers
  • paper towels, preferrably a good absorbent brand like Brawny--at least one full roll
  • workbench, large table or sawhorses for spreading out piano parts
    blocks of scrap wood (optional), for raising your pieces above the table, thus preventing your work area from getting too gooey too quickly.
  • screwdrivers of various sizes: at least one small and one medium to medium-large, flat blade. Some newer pianos may have phillips head screws, but most do not.
  • about 10 or 12 small or letter-sized envelopes (for keeping track of screws as you disassemble piano)
  • trash receptacle or paper shopping bag for disposing of gooey paper towels

strip_supplies.jpg


Disassembling the Piano

To do an attractive refinishing job, every removeable cabinet piece must be removed from the piano and done separately. It is wise to sketch out the piano beforehand and label where your screws go, then put them in the envelopes as you take the piano apart. The following guidelines are for uprights, but grands are similar. Take the cabinet apart piece by piece, usually in the following order:

* The lid: if a two-piece lid, open it and remove the long hinge. On the back side of the hinge, make an “R” with a pencil or permanent marker to keep track of which end goes to the right. If the lid is a one-piece, remove the pins from the hinge in the back of the piano, then remove the half of the hinge left on the lid, label them “L” and “R”, and put them along with their screws in envelopes.

* The top front panel and side rails: This is the large board running across the top front of the piano. It often has vertical pieces mounted to the sides of it. Sometimes the board and these “side rails” are removed as one unit and then taken apart. If so, you will find some kind of latch inside the piano just under the lid. Image: Cabinet PartsUndo the latch, tilt the entire unit toward you, and lift it out. Then dissemble it, keeping track of any screws, hinges, or wood blocks you remove. More often, the front board is separate from the side rails. If so, it will be suspended from the rails by some kind of hangers or hooks. To remove it, grasp it from the top center and bottom center of the board, and lift it as you pull it forward. Such a front board can usually be refinished with the hooks left in place. The side rails can now usually be removed by removing the screws that hold them to the sides of the piano. Also, if the front board has any inset panels, such as decorative panels, they usually are screwed in from the back. These should be labeled and removed.

* The music shelf can now be removed, usually by removing the screw at each end and lifting the shelf out. Sometimes there are no screws; the shelf can simply be lifted out. Sometimes it must lifted from one end first, then pulled to one side to clear the pegs, then lifted out.

* The keyslip, which runs in front of the keys, is taken off by removing the 3-5 screws holding it from underneath the key bed.

* The fallboard or nameboard: This is the piece that folds over the keys, and usually has the manufacturer’s decal on it. Remove it by folding it down toward the keys and finding the screws behind it holding it to the end blocks. Remove the screws, lift out the fallboard, and (in most pianos) remove from it the strip which lays across the keys. Then remove the long hinge that usually connects the two main parts of the fallboard. If the fallboard has knobs, they can sometimes be unscrewed. If not, they may have peg ends and will probably need to be spoiled as you remove them (They can be replaced later). Label and keep track of all hinges and screws.

* The key blocks, which are the blocks mounted at each end of the keys, can now be removed by taking out the large screw that holds each one to the key bed. In some cases, the block is held in place by a large screw that goes up through the key bed from underneath.

* The bottom front panel can be removed, usually by pushing up on the leaf spring which you will find under the key bed. If the board has any inset panels, label which way they go and remove them.

* Some pianos will have a decorative plate over the pedals. This should be removed. The pedals are not easily removed, and therefore should be taped over with masking tape to avoid getting old dissolved and new finish all over them, thus making them difficult to polish later.

* Most pianos cannot be disassembled any further without doing complicated things like putting the piano on its back and other “impossible” stuff.

Setting Up Your Job

Set up your worktable or workbench, and the entire area around the piano, by covering the area with newspapers, spread thickly to prevent spills from soaking through (especially around the piano itself, which usually must be done in the living quarters of the house). If you are working on a table, have the wood blocks handy, and use a block for each end of the piece you are working on. If you are using sawhorses, the blocks won’t be necessary. Try to work in an area that can be ventilated, but don’t ventilate so much that the room gets colder than around 60 degrees, or you will find the stripper too stiff to work with.

Stripping Procedure

Decide which part of the piano you will start on. If you are inexperienced, you should find a flat and easy piece, one not too large, to begin. Lay out the piece, or a few pieces at a time once you get used to it, on the wood blocks or across the sawhorses. Fill one of the coffee cans about half full with the 5F5 stripper, and choose the appropriate brush according to the size of the piece. Then put on your stripping gloves and follow the following procedure:

1. Applying Stripper:
Brush on a liberal coat of stripper, preferrably brushing in the direction of the wood grain. Wait about 5 to 10 minutes for the finish to dissolve. (You will develop a feel for how long to leave it on: too long and it will begin to dry and harden, and thus it will be difficult to scrape off. Too soon and it will not have dissolved enough finish.)

2. Scraping the Dissolved Finish:
Choose the appropriate putty knife or scraper, along with an empty coffee can, and begin scraping the dissolved finish and “wiping” the goop off into the coffee can. For curved areas, you will have to be creative as to how to scrape it off. On most inside curves, you can either find some nimble way to use the straight scraper, or you can use your homemade curved-tip scraper. On outside (or impossible inside) curves, if you can’t use the scrapers, simply don’t scrape them; keep applying subsequent coats of stripper and don’t remove it until the “washing down” step explained later.


knife_round

A rounded-tip scraper ground from a potato knife

Repeat the above step as many times as necessary to get down to the bare wood. You will “feel” the wood once you’ve gotten below the last remaining finish -- the scraper will slide smoothly without any “sticky” feel. Most old finishes can be removed in two or three applications. Don’t worry about the goop left on the wood between scrapes -- it will all come off when you wash it down. Also, try not to do any more pieces than you can complete through the next step; otherwise, the goop will harden somewhat and will not wash off as easily in the next step.

3. Washing down:
Take another coffee can and mix equal amounts of the lacquer thinner and alcohol. Take a roll of paper towels and separate it into a pile of single sheets. Take a piece of green scratcher pad, a piece no larger than about 3” X 3” or 4” X 4.” Dip it into the solution and apply liberally to the piece with a quick back-and-forth or swirling motion. This will dissolve any goop left on the wood. Now, working quickly before the liquid dries, wipe if off with the sheets of paper towels. The liquid dries very quickly, so don’t do an area any larger than you can wipe up before it dries. You will find that it cleans off all the goop and leaves you with a nice, clean wood surface. If you notice some areas that still have finish on them, apply a little stripper just to those areas, wait a few minutes and repeat the washdown procedure (you don’t need to scrape the stripper off this time, unless it is a large, easy-to-scrape area).

4. Stripping Detailed Areas:
Any detailed areas that you have chosen not to scrape you may also wash down with the lacquer thinner/alcohol solution and scratcher pad. Work the pad into difficult areas as well as you can, then wipe down with the paper towels and repeat the procedure. Eventually you get down to the bare wood even without scraping, even if you need an extra application or two.

Preparing Wood for Finishing:

Once the stripped wood has dried for several days, it should be sanded with 100 or 150 grit sandpaper to remove any “haze” of chemicals that remain, to smooth out the wood, and to prepare the wood for staining. Be careful not to sand too heavily on the edges or corners, since this will remove more stain than surrounding areas and leave light outlines around the edges. After sanding, clean out the sanding dust by vacuuming the wood with vacuum cleaner and a soft brush attachment.

Staining

After stripping, much of the original stain will remain in the wood; however, applying a coat of stain will help blend in any streakiness and provide a uniform color. Also, you may be able to change the existing stain somewhat, by making it more red (e.g., with red mahogany stain) or brown (e.g., walnut or brown mahogany stain). Lighter stains like pine or oak will usually have no effect on stripped wood.

Finishing

Since so many types of finishes are available (solvent-based, water-based, lacquer-based, alcohol-based, etc.), and so many methods (brush-on, wipe-on, spray-on, etc.), you should consult your paint or hardware store, tell them your circumstances, and let them advise you on which method to use. However, keep the following principles in mind:

1. Types of Finishes: The solvent-based polyurethanes are very hard and provide good protection, but they are also harder to work with and clean up after. Furthermore, environmental concerns have driven things in the direction of water-based finishes. It is especially important when applying a water-based finish over previously finished wood to clean the old wood with a wax and silicone remover to remove any traces waxes or silicates that could affect the adhesion of the new finish. Water-based finishes are especially vulnerable to this problem.

2. When applying multiple coats of any type of finish, fine sand in between coats with an extra-fine sandpaper (such as 400 grit). This will produce a much smoother finish. The first coat, especially, tend to turn out very rough because of dust or torn wood fibers due to sanding.

3. Polishing your final coat: The final coat may be brought to a smooth sheen by the following procedure: (1) Using 400 grit wet-or-dry sandpaper and a bucket of water, wet sand to smooth out and rough spots in the finish, being careful not to sand back down to bear wood. First spread a little water on the area you are sanding; dip the sandpaper in the water and sand in the direction of the grain. Do not let the surface become too dry. When you think you have sanded enough, use a damp cloth and a clean bucket of water to wash off the surface. When it dries, feel to see if it is smooth. If so, move on to the next step. (2) Now you can polish the surface using a good paste wax (such as Mothers Wax or Butchers Wax) and 0000 steel wool (pronounced "four aught," the finest grit generally avaiable in hardware stores). The best procedure is to follow the directions on the can, but I use a lttle water to wet the steel wool before I put it in the wax. Apply the wax in the direction of the wood grain, allow to dry for about 10-15 minutes, and buff it out with a clean, dry rag.

For the perfectionist, I recommend doing further study on finishing techniques via a good book or on the internet. Hopefully, this article will point you in the direction of a refninishing job that you and your family will appreciate for years to come.

 


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