Headless Kit Build: Wet Sanding

During the first week of the finishing process, I have been pretty generous with oil applications. Before the oil builds up it soaks right in. So it helps to be a little aggressive (a few drops) at the start if you're going to use a coat/wait/coat approach. The downside is you get some bumps, mini dust bunnies stuck in the muck and ridges in the finish. The key to getting rid of those is wet sanding!

This involves soaking a paper towel with water, squeezing a few drops out, and then sanding out imperfections with a grit that depends on the severity of the "unsmoothedness". I use between 800 and 1500 grit. As you sand you build up a slurry of powdered oil and water. I find it works really well to get the gloves off and have my fingers in the Tru-Oil mud so I can feel the texture of the surface as I'm sanding. Wiping it off with the wet paper towel, the surface looks a bit duller than before the sanding.

After it dries, you can see the remaining "mud" stuck around the imperfections. That effect will go away with a naphtha wipe down and additional coats of oil.

Headless Kit Build: Three More Days of Tru-Oil

At this point, I've almost worked my way all around the sides of the body and the back. The top is still to be finished. Here's some progress over three days with three to four coats per day.

You may wonder what I do with all the coffee filters. Especially since Tru-Oil has a habit of spontaneous combustion. I hang them up so the oil can cure in my shower. There's a lack of flammable material nearby. And the room has good ventilation. So far this has worked out.

Headless Kit Build: First Six Tru-Oil Coats

I'm about a day and six coats into Tru-Oil application. Five on the back and one on the sides. That seems like a lot of coats for just over 24 hours. Especially considering I was not home most of today. But with thin enough coats (just a few drops) it is possible to re-apply every three hours or so. As soon as the last coat is no longer tacky. I enjoy this approach because it means even on a workday between the morning and the evening I get at least two, maybe three chances to spend 5-6 minutes moving the project forward. In a busy week, I'm still able to make a lot of visible progress with less than an hour of time to put into it.

Here's a bottle of Tru-Oil. The big bottles like this are a slightly better value but unfortunately because Tru-Oil does thicken and get hard as it is in contact with oxygen if you don't use it fast, all sorts of bad things happen. The texture changes. It yellows a bit more (might not be bad, depending on what you're going for). And you get "crusty attacks" all around the cap. Little critters that jump off the bottle onto your project.

So I definitely recommend making a very tiny hole in the foil gap and to slow this process. It also helps to avoid pouring out too much of the oil.

In this case, the hole I made was actually a little too big. I use cheap coffee filters (like the ones from Duane Reade) to apply Tru-Oil. I have read that some people use specific filters like Melitta natural browns. I tried a few kinds. And in the end, the finer filters fall apart too quickly on me and I end up needing to sand fibers out of the finish after a few coats. The brittle white paper ones are perfect to fold over a few times and sturdy enough to not come apart against the surface while spreading oil around.

Here are the first five coats on the back.

 And finally, tonight I started around the sides.

As this moves along I'm going to need to start wet sanding the oil level as it builds up. This will dull the finish a little but the goal is to get it thick enough and flat enough that we can go back and buff it out later. The key thing is that the thinner each coat is, the less work there is sanding out mistakes later. Another big problem is dust getting onto the sticky oil as it hardens. That is unavoidable in a small workspace. More sanding. More patience.

Headless Kit Build: Sanding and Scraping Binding

There's a bit more before applying the first coat of oil on this one. Sanding was straight forward. After the sealer applied in the last post dried, I worked up to 1500 grit and made all of the surfaces smooth to the touch. Because the dye is now protected by the sealer, I did not have to worry about accidentally removing dye.

Then I started on the binding. I've never scraped binding before. I don't have a binding scraper like this one so I first went at it with a razor knife. That wasn't going really well. I almost slipped a few times trying to dig into the binding. So then I went at it with sandpaper. That created the nice white powder all over the body but wasn't getting the binding looking nice, clean and well defined.

So I went back to the knife. It took a little while but keeping the angle fairly perpendicular (a small angle) to the wood and just being confident with fast, brushing like movements, sort of like whittling, started to take off material. And the box cutter provided just enough control for me to keep the lines straight. The blade itself is so small, the few times I missed it didn't make noticeable marks in the sealed wood.

By this picture you can see, if you look closely, especially along the right edge, that the binding line is starting to pop out a bit more.

Here's after vacuuming it off and doing a wipe down with naphtha. In the brighter lighting you can see the binding now creates a clear outline without any leftover color. You may also notice some dull spots on the neck (near the heal) and on the top. This was the result after sanding back some of the sealer. You'll see later that with the oil applied, those areas will shine right up.

I mentioned cleaning with naphtha. Naphtha seems to be the one stop shop cleaning solution for guitars in general. I use this one.

The bottle has a nice safety top on it which is something that is valuable if you're doing all of this in a small apartment. You can find this one here. Naphtha coated rags take the extra dust, both plastic and wood, right off the body and leave it in good shape to apply a coat of oil. That is coming next!

Headless Kit Build: Final Color After Sealer

I'm going to sand and start oiling today but here's the final color after the Birchwood Casey Sealer has dried overnight. I do not plan to apply any grain filler. The grain is pretty closed as it is, except for the end grain.

Despite there usually being almost no figuring in basswood, if you look on the left side of this picture closely, you can see a bit of light flame. It only appears on this side though. Hopefully it becomes even more apparent after a few coats of Birchwood Casey Tru-Oil.

You can also see one of those little yellow pads on the right next to the guitar.

That is what I use to apply the sealer/filler. I like these over a rag because they're just spongy enough to soak a little up and spread it. The sealer is tacky so it is nice to be able to pour it on, pick some up and move it quickly. They're cheap so they're great for one time use. The sealer is going to pretty much destroy them. Here's a link to get some on Amazon.

Headless Kit Build: Color After Birchwood Casey Sealer

The build continues today with an application of the Birchwood Casey Sealer and Filler after a light 1000 grit sanding. This is with just a bit of sealer in different areas to show the contrast. Even after it dries, the color difference won't be much as it keeps a "wet" look with the sealer on it.

And here's the back.

I went back and sanded the end grain a bit more to keep it from just consuming all my sealer. You can see how basswood darkens up at the end grain on the bottom of the body and around those bottom corners.

These little bottles are $6-something a piece. I was also sad to find one of my half bottles had dried out over the months. You have to use it fast. Now I wait for it to dry. And try to avoid the fumes. This is by far my least favorite part. Excited to start the oiling.