Finish repairs, refinishing, and finishes in general are high on the list of the most common inquiries a guitar tech deals with every week. The typical problems are dings, scratches, chips, dull spots, and cracks in the finish caused by structural damage. Less common (thankfully) are flaking and peeling finishes caused by flawed preparation and/or defective materials.

I’ve dealt with all of the above annoyances many times and I’m currently of the opinion that the most critical aspect of any finish work is the customers’ expectations. Obviously the technician needs a good understanding of the materials and techniques involved, but sometimes even a finish repair wizard (yes there are a few) will not be able to make a scratch or ding totally vanish.

When a customer brings in a finish repair job, just about the first thing I say is “You’ll probably always be able to see where the damage was.” I don’t say this to lower his expectations, but rather to establish a “reality” baseline.

When we are upset over a wound on our baby we’ll likely obsess a little and constantly be looking at the area that was damaged. Virtually no repair can stand that sort of scrutiny. Most of us do this. Last year my pristine (and obsessively polished) car suffered a minor collision……ARRRRRRGHHHHH!!!! It was well repaired by a good shop but guess what? I know where the damage was and I cannot help but examine that area umpteen times a month and sometimes I think I see the dent and scrape…….go figure.

So, what can you realistically expect when that gorgeous 335 or the near mint ‘55 J-50 encounters a blunt object? Let’s examine a few typical categories of finish damage.

Scratches are the most commonly encountered finish repair tasks. Here’s the good news: they can frequently be made to disappear if they are not so deep that the wood underneath is damaged. Nail marks, pick scratches, and minor abrasions, even really ugly ones are often repairable with careful buffing. Sometimes deep scratches will respond to careful wet sanding followed by buffing.

The worst scratches are found on the soundboards of acoustic guitars when overzealous playing leaves what we call a “zipper” where the pick skids across the grain, leaving dents in the wood under the finish. On light colored wood this is nearly impossible to eradicate. We can fill the finish damage but removing the dents in the wood can get very complicated, needing delicate local steaming and occasionally demanding a complete refinish on the soundboard. That this can get VERY expensive is obvious.

Dings and dents are generally in need of filling, leveling, and buffing. The technique known as “drop filling” is effective and when done properly can pretty well hide some nasty dings. A drop fill is just what it sounds like: a drop of appropriate finish material is flowed into the ding, allowed to cure, then carefully leveled with the surrounding area and buffed to match the rest of the finish. The main problem with drop fills is compatibility between the repair material and the original finish. Guitars finished with nitro cellulose lacquer respond well to a drop of nitro which usually melts into the original finish nicely. The downside of a nitro fill is the relatively long cure time before leveling and buffing.

Fills can also be done with cyanoacrylate (super glue) which eliminates the long cure times but introduces some other problems and often looks like a little island of alien material. It cures clear and hard but its transparency does not always equal the original finish. Super glue is often the only material to use with modern poly finishes such as those used by Taylor, Goodall, and others.

Chips can sometime be filled, but usually chips or peeling areas indicate an adhesion problem which might be the top layer of gloss finish or a problem with a sealer/primer. Most of time this sort of difficulty can be traced to a problem at the manufacturing stage and might be covered under a warranty if luck is with you. This kind of problem often needs a complete refinish and that is in the VERY, VERY EXPENSIVE category.

In a future post I’ll cover some aspects of original finishes and refinishes, pros and cons of nitro cellulose lacquer vs. modern polys and a few other finish topics that guitar geeks (you know who you are) love to argue about.