Chapter 5: Refinishing Project Clock: Case Refinishing

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1 Chapter 5: Refinishing Project Clock: Case Refinishing If you followed chapter four Case Restoration and the related Project Clock section you are aware that our project clock has had a significant amount of repair performed. This included repair of damaged boards, creation of missing pieces for the lower cross-piece and door, reattachment of loose veneer and application of new veneer where missing. Although the case, when received, was in extremely poor condition and likely to be scrapped as hopeless by some, it is now structurally sound, accurate and ready for refinishing. In this section, the techniques covered in chapter five will be used to stain, conceal flaws and apply an accurate, authentic finish to the clock case. The case is still in a disassembled state as found in chapter four. It will be stained and finished prior to assembly. Final polishing of the finish will be done once the case is assembled, but there are certain advantages to getting the bulk of the finish work completed while case parts are disassembled. Preparation: The first step in finishing is to identify and correct any remaining flaws in the case. Before beginning to correct flaws, first consider what you are seeking in a finished product. Keep in mind that in most cases you are not trying to produce a pristine clock that looks like it just came from the assembly plant. The project clock is a case in point. It is over 150 years old and even it had been maintained with exceptional care it would have naturally accumulated a number small dents and/or scratches. Some of these character lines should be left to better reflect its history. Which flaws should be corrected and which should be left as-is is a matter of taste, but keep this concept in mind when refinishing a case. Prior to staining, the project case is lightly rubbed with steel wool and inspected to identify flaws which will require repair prior to refinishing. It was found that both vertical sides have minor damage On the left side, a gouge was noted in the veneer. It is too small to justify installation of a veneer patch, but is large enough that it should be repaired.

2 A stainable wood filler will be used to repair this flaw, but it will be applied after staining of the rest of the panel. The flaw will then be carefully stained to blend in. If after staining, the repair is too obvious, faking will be used to further blend the repair into the surrounding case. The two pieces are sanded flush and the small gap filled. Staining of the old and new veneers will require a little extra attention. Some small splitting of old veneer is noted on one of the side pieces. On the other vertical side a small nail hole was found. This was easily filled. Another flaw that was identified was on the upper front molding of the case where a small piece of new veneer was attached next to some existing veneer. These are filled with stainable filler prior to staining.

3 On both the left and right lower stanchions the veneer on the fronts is new while the veneer on the sides is original. This will require careful staining to achieve a good match. Staining begins by applying stain to all of the old veneer. Staining of new veneers will be started once the original veneer is brought to the proper color. With the minor flaws identified or repaired the case pieces are ready for staining. Staining: Based on review of a number of samples of similar clocks, it was determined that a medium-dark walnut stain would provide the best match to the original case color. Staining of the sections of old veneer has been completed and the wood-filled areas are next addressed. A small artist brush is used and is kept almost dry as stain is carefully applied to the filler. Three MinWax walnut stains (Walnut, Special Walnut and Dark Walnut) were tested on a scrap of harvested veneer to confirm the color. The Special Walnut stain is selected as the best match. The stain has brought the color of the filler very close to that of the surrounding case,

4 but the un-grained nature of the filler still makes the repair quite obvious. A small amount of faking will be needed to completely hide this flaw. Once the stain has completely cured, the case section is very lightly steel wooled and wiped with a tack cloth. The veneer around the flaw is studied to get a feel for both the color(s) and the general graining. Once satisfied that the flaw has been blended in, the other flaws are inspected and faked as necessary. Initial colors are chosen and a very small amount is applied to the veneer to confirm the match. The next item is staining of the various sections of new veneer. A test piece is created using a scrap of harvested veneer glued next to a piece of new veneer. The initial color selection is slightly too red so a tiny amount of brown is mixed in and additional tests are performed until a good color match is achieved. With the correct color achieved, it is worked over and around the wood filler to blend this flaw into the look of the grain around it. As was done in chapter five, an initial coat of the stain used on the old veneer is applied to a scrap piece of new veneer to determine how to approach the staining. As can be seen in the photo, the stained used on the old veneer is missing the slight red shade that is seen on the old veneer with the same stain.

5 Addition of a light coat of Red-Oak stain over the base stain of walnut brings the new veneer tone into a match with that of the old veneer. The need to use different or multiple stains to get a good match between old and new veneer section is fairly common, but can usually be achieved simply by applying the original stain used on the old veneer then closely comparing the result on the new veneer. Usually you will see that more brown or yellow or red is need to reach the correct final color. Working with one section of the case at a time, each section of new veneer is carefully stained first with the special walnut stain and allowed to dry. A light staining with red oak is used to make the new veneer match adjacent old veneer. Good lighting should be used when attempting to match different veneer shades. With the correct stain sequence worked out for the new sections of veneer, the case panels are stained to match the surrounding old veneer. The stained sections of old veneer are used as a handy reference to ensure a good match. All of the case pieces have now been stained to the desired color and allowed to dry. Pieces are once again closely examined for flaws prior to beginning application of the final finish. Finishing: As noted in the main part of chapter 5, most antique American clocks were finished with either varnish or shellac. Testing on similar Seth Thomas clock cases

6 indicates that the original finish was likely shellac. Clocks of the type being restored were manufactured in large quantity and intended to be low cost consumer goods. As a result, the final finish was applied more with an eye toward wood protection and cost effectiveness versus a fine furniture finish. Shellac was used because of its low cost and protective quality, but also because it dried very quickly. This left less time for contamination on the finish and helped keep production moving. The original shellac finish was most likely applied by brush. This would be a perfectly acceptable approach in restoration of the clock, but instead most panels will be finished using a polishing rubber as was shown in chapter five. The reason for this is purely a personal choice. Prior to beginning finishing, a number of cloth pads are cut. It will be necessary to change to a fresh pad several times during the finishing process. A cotton ball is pressed into each pad then the cloth is held together while a rubber band is used to hold the cotton ball tightly in the rubbing pad. Tip: If a panel has been heavily stained to achieve color, it is usually best to apply several coats of shellac with a brush. Rubbing shellac could loosen some of the surface stain which then creates a contaminated shellac mixture that becomes gummy and does not spread smoothly. After several coats of shellac have been applied and allowed to cure for about 24 hours, it can be lightly sanded with #600 grit sandpaper using olive oil as a lubricant. This will smooth out the shellac which can then be rubbed to a final finish. While shellac flakes are currently available in clear as well as a number of shades, orange shellac is the original and most commonly available type. This is the type of shellac that would have been used on the original case and will be used for refinishing. One ounce of shellac flakes (by weight) is mixed with four ounces (by volume) of alcohol to mix up a fresh batch of shellac. Any shellac that is over about two weeks should be discarded in favor of a fresh batch. You will find that fresh shellac is actually easier to apply, dries quickly and fills grain more readily.

7 the shellac to flow smoothly and easily onto the wood. You will need to re-apply alcohol on a regular basis to maintain this level of moistness. To begin, an eye dropper is used to apply a generous amount of straight alcohol to one of the rubbers. It is then tapped against a piece of plain typing paper to get the concentration just right. Select a panel to begin with and position it where you can work easily and apply a reasonable amount of downward pressure. If the rubber creates splatters on the paper when tapped, it is too wet. Keep tapping until the rubber leaves a definite wet spot, but does not send out splatter marks. Begin by shaking the shellac well, then using a dropper to apply a small amount of shellac to the face of the rubber. Keeping the rubber adequately moist with alcohol is a very important step in getting

8 Rub in line with the grain, from one end of a surface to the other. This is known as the sealing-coat. Reapply shellac as needed to lay down a smooth coat on all of the surfaces you are finishing. Allow about five minutes for the sealing coat to dry then repeat the process. Use this technique to apply about three sealing coats. Allow to dry for at lease a half hour. Begin at one end of the panel being finished and start making small figure eight motions with the rubber. Some pressure is applied in order to force the shellac and pumice down into the wood grains. Use a sealable glass jar to store your rubbing pads when not in use. Put a five or six drops of alcohol in the bottom of the jar, then drop in the pads. After the sealing coats, the filling coats begin. This is a process of using shellac and a small amount of pumice to fill the small grains of the wood. The pumice has an added benefit in that it is mildly abrasive and actually polishes the shellac. Do not allow the rubber to stop while in contact with the wood. It will leave a mark where the shellac is pulled from the rubber. A rubber is removed from the jar and remoistened with alcohol. A small pinch of pumice is spread on the face of the rubber then shellac is applied. Work on only a small area and watch the progress. You should quickly see that the shellac is starting to fill the wood grain and create a smooth shiny surface.

9 Be sure to check moisture in the rubber often. If it becomes too dry, the shellac will become dry and cause the rubber to become sticky on the wood. with the grain. This is the same motion used for the sealing coat. Once one area is filled and smoothed, advance to another area and repeat the process. A very light application of olive oil is applied to the face of the rubber to aid it to glide smoothly. Once the entire panel has been filled and smoothed allow it to dry and harden for about a half hour. Only a light pressure is necessary at this point. The combination of olive oil and shellac on the rubber will smooth the finish and ensure that any directional marks are in line with the grain. The final shellac is applied with a fresh rubbing pad to ensure that no pumice is present. Apply alcohol and shellac as before and work over the entire panel until you are satisfied with the depth of your finish. To complete the job, make straight runs from one end of the panel to the other in line

10 Once completed, the panel should be allowed to dry and harden for at least two or three days. At that time you can examine the case to determine if the finish is to your liking. The cured shellac is lightly sanded to smooth the finish. It is then rubbed to a final finish with a rubber and more shellac. Often, you may find that a case finished in this manner is actually too shiny for an authentic look. To tone down the shine, the finish is very lightly buffed with steel wool after it has completely cured. This is usually done after the case has been assembled. The lower cross piece of the case was created from scratch and veneered with new veneer. To achieve a good match with the rest of the case, walnut stain was applied then a coat of red oak stain. While the stain appears to be fully absorbed initial coats of shellac are brushed on to avoid any possible contamination of the finish. Each panel of the project clock has been finished with shellac and allowed to cure for several days. All pieces are compared to ensure a uniform finish from panel to panel. After the case has been assembled, minor final finishing will be undertaken to achieve just the right finish look. Summary: The case has come a long way from the damaged and faded pile of wood it started as.

11 Once assembled, the benefit of the work performed in previous chapters will become readily apparent. Here the main components of the case are laid together to get a feel for the finished product. Final assembly will take place once all other case parts (backboard, columns, etc.) have been repaired and/or refinished. In finishing the case it should be noted that things don t always go exactly right the first time. When matching old and new veneer you may find that when you apply shellac the old and new veneers just do not match well as you thought they did or an area that you faked is just too visible. In most situations it is better to complete the finishing including the steel wool work before making any final decisions. If an area of the case finish is found to be unacceptable, it may be best in the long run to use some alcohol and #0000 steel wool to remove the shellac from the problem section and start over. This of course means extra time and work, but in the end, you are likely to be glad that you made the extra effort to make the refinishing correct and accurate. Remember, you are preparing the clock for the next 100 years of service.