|Forum topic by Jerry||posted 12-10-2010 07:18 PM||1567 views||9 times favorited||11 replies|
12-10-2010 07:18 PM
I took a woodworking finishing class out at my local JC and the instructor taught me this very cool patch trick. If you do this correctly, your brad holes or other small voids will be, for all practical purposes… INVISIBLE! I have used this technique on a number of projects with excellent results!
The problem: When you patch a hole in bare unfinished wood with commercial wood putty it looks great! It looks great…that is…until you apply stain and/or clear coat. After the application of stain or clear coat, the brad hole patch stands out like a sore thumb because it’s now a different hue than the wood. To make matters worse, the round symmetrical shape of the patch only accentuates the color variation.
The solution: Take your sanded bare wood project and apply your stain (if staining) and then the first clear coat. It can be polyurethane, lacquer or whatever. Allow the first clear coat to dry. From this point forward, additional clear coats will not significantly change the color of the wood. Now, using white painters putty and universal color pigments, you can match the putty’s color perfectly to the color of the wood, fill in the holes, allow the putty to dry and then apply the remaining clear coats. Voila, a perfect match!
Required Materials: Rubber gloves, oil base painter’s putty (oil base will not shrink), and three universal colors, “raw sienna”, “burn sienna” and “burnt umber”. Use raw sienna for the yellow woods like maple & pine, burnt sienna for the reds like mahogany and koa, and burnt umber for the browns like walnut & teak. The theory is, “you can mix-and-match these three colors to match any wood color”.
Wearing rubber gloves, take a walnut sized batch of white painters putty and mix-and-match the universal colors into the putty until it matches the color of the wood. If there are variations in the woods color, match the lighter color first then break the putty in half and match the remaining half to the darker color. Now you have two balls of tinted painters putty, one lighter shade and one darker shade that match the colors in the wood.
Dry out the putty by working in a small amount of corn starch into the putty by rolling it between the palms of your hands. Don’t over do it, just enough so it’s not too sticky to work with.
Roll the putty to a fine point, push it into the void then break it off. Work it in with a small plastic putty knife or similar object if necessary. (I made my own small application tool by cutting up a bondo applicator.) Do not sand! Let dry for 24 hours. If the patch disrupts a line of grain, take a very fine artist brush and draw the grain line back in using the appropriate universal color(s). You can also use a colored pencil.
Now you can apply the remainder of your clear coats. The additional coats will not change the wood color or the putty color.
Store putty in plastic bag in the refrigerator. It will keep for a couple of days or so.
-- Jerry - Roseville, CA