Different techniques and materials can be used to repair wood finishes with gouges or deep scratches. These damages can be filled with a range of wood fillers. Anything from colored wax sticks, wood putty, furniture wax, drops of finish, and burn in sticks made of shellac or lacquer.
There are also many things to consider when determining which will be best for your restoration project. Repairs to wood finishes will blend in best when you have factored in color, body, texture and sheen. For example, you can have a perfect color match, but if the texture or sheen is off, the repair will be noticed.
This page shows the basic process used to repair a scratch with a burn in lacquer stick on one of our projects.
Burn in repairs are usually done on existing wood finishes with a hot knife or as I call it, a burn in iron. This technique is mastered only through experience, and not something I recommend practicing on that is of any value.
To show the burn in repair process I am working on the crest rail of an arm chair. This chair is one of 6 new mahogany arm chairs. For whatever reason, the maker decided to put this one distress line (as they call it) right in the middle of one of the crest rails. I don’t know what to say, other than – wow.
Anyways, the client was not impressed and I was asked to fix it.
Looking at the existing finish we see that it is an open pore lacquer finish. The sheen is semi-gloss, and the wood is stained a traditional mahogany color.
In my favor, the damage (as I call it) is in the direction of the grain, and although open pore, the finish has some pretty good body (thickness).
One option is to fill the damage with putty and touch up as best as possible. But through my own experience, I know that for this project a burn in repair will blend in much better. Filling with a like material (lacquer) will be a plus, and will minimize the amount of touch up after the scratch is filled.
The scratch gets filled with lacquer by using the burn in iron and lacquer stick. The moment this filler cools it hardens, and because it does not shrink, it takes only one application.
The basic idea is to fill only the damage, and as little as the surrounding area as possible.
It takes practice, but learning how to get a smooth fill as quickly as possible is important. With every pass of the hot knife the existing finish is at risk.
After all is filled the repair then gets sanded flush. This I do while wet with Rosini’s Rejuvenator and 400 wet/dry paper.
Sounds simple, but this is where it can really go wrong.
If sanded too aggressively, there is risk of cutting through the existing finish and color. If this happens it just adds more work to the project.
To make sure all is flush, I inspect closely from different angles, knowing that any ridges left behind will be magnified at the final step – polishing.
By repairing the scratch with this burn in technique, I had minimal touch up and polishing to blend all together.
The completed project shows a good wood finish repair that blends well in color, body, texture and sheen.
What’s your favorite technique to repair deep gouges or scratches in wood finishes?