This is How to Make an Acoustic Guitar – Part Thirty – Smoothing the Neck. In this part of the series I’ll show you how to clean up after the Sureform, and make your neck very smooth to the touch. There will be tips and tricks as well, enjoy.
Smoothing the Guitar Neck
Earlier in the process, I showed you how to rough out the acoustic guitar neck and create the initial shape and profile. This was done with a sureform, which is a very aggressive tool, and it leaves a lot of tool marks behind.
At this point, those tool marks all need to be cleaned up, so that way the neck can be sanded down to finish smoothness. After all, no one wants to play on a jagged neck with lots of splinters.
This is largely a process of going through the different sandpaper grits, or using different edged tools to create a smooth surface. If you’re comfortable doing this process, it will be very similar to any other sanding project.
However, it’s worth talking about because those who are new to sanding and making an instrument may not realize that there is light at the end of the tunnel. All you have to do is keep on sanding, and eventually it will turn out.
If you missed last week, take a look at How to Make an Acoustic Guitar Part Twenty Nine.
Check the Damage First
One of the first tips that is very important to know when you’re sanding a big project like a guitar neck is to assess the damage first. You need to figure out where your starting point is, that way you can pick the best tool.
You need to start fairly close to the existing damage as far as coarseness, that way, you’re not spending a ton of time with sandpaper that’s not super effective. If you are using a cabinet scraper, this is still an important step.
For example, you wouldn’t want to start with 4000 grit sandpaper right out of the gate. Even though 4000 grit is a very fine smoothness, it would take you a lifetime to get there from where you are currently starting.
Though that’s an extreme example, it would still be a waste to start with 220 grit. This is why you need to start with the next smoothest grit that will improve at the surface. After the sureform, that’s likely going to be 80.
See Also: 12 Awesome Uses for 80 Grit Sandpaper
Choose the Right Tool
Now that you have an idea of your starting point, it’s important to choose the right tool to begin with. In most cases, 80 grit sandpaper is going to be the first step. However, there are others to choose from.
If you decide so, you may use a flat file or a round the file to clean up the marks left by the sureform. From there, you can go to 80 or 100 grit sandpaper, and begin the sanding process. It’s completely up to you.
As well, you may choose to do the entire thing with the cabinet scraper. This is a good way of smoothing a surface, just keep your cabinet scraper sharp. Work in large sections, and think blending as you are working.
See Also: 13 Great Tips for Using a Wood Scraper
Most People Don’t Sand Well
If you want to have a good experience sanding the back of the neck, you need to do it in a way that isn’t going to take 30 hours. The way you do that is easy, and I’ll show you exactly what you need to do to be successful.
First of all, you’re already starting with the right grit, which is a big hurdle for a lot of people when they first start sanding. You always want to use the most aggressive grit that you can, which will still improve the surface.
That’s a two-part sentence. The most aggressive grit, plus still improves the surface. If 80 grit makes the surface better, then it’s not too aggressive. If it makes the surface worse, then you need to start with something finer.
This will lead you right into the next sanding mistake that people make, so you hopefully don’t make it yourself.
At some point you’ll notice the grit that you were using is no longer improving the surface. The split second you notice that, it’s time to change to the next smoother grit. Sanding with the same paper past the point at which the surface stops improving is not effective, so change quickly.
As soon as this next grit is no longer improving the surface, switch again to a finer grit. Do that all the way down to 220, and your neck will be very smooth. It will also be one of the faster standing experiences that you’ve ever had before.
See Also: 17 Important Tips on How to Sand Wood
Check the Neck From Several Angles
It’s important after you do the majority of your sanding to check the acoustic guitar neck from several angles to ensure that the process is going along smoothly. Check at regular intervals during the process as well, and know where you are.
The guitar neck is a long, slender piece of wood. So you can sight down the length of it by holding it up to your eye, and rotating the neck to check the profile. Do this often, and look for any bumps or valleys that need to be improved.
The more often you check your neck, and target the areas that need improvement, the better the process will be. Your neck will look a lot more even, and you’ll spend a lot less time sanding than most do.
See Also: 7 Helpful Wood Sanding Machines
Sand the Neck to 220 Grit
Since the finish will be applied to the back of the guitar neck, it’s not really too important to sand the neck beyond 220 grit. Anything smoother than that will be taken out by the finish application anyway.
As discussed in the previous actions, you are essentially in a race through your grit levels to get to 220. Once you’re at 220 grit, and the surface no longer improves, you’re done.
Look for more scratches one last time, take them out, and you’re able to move to the next step.
End Grain Sanding Advice
There is one part of sanding your guitar neck that is going to be a little frustrating. It’s frustrating for me every single time, but I know how it works, so I have faith in the process and I stick to it.
In the beginning, sanding the end grain, which is primarily going to be visible in the heel section of the neck will seem to be completely impossible. You will sand, and sand, and sand, and it will seem like nothing is happening.
Even though it seems like those tool marks aren’t going anywhere, they really are. It’s just a slow process. Stick with it, and don’t give up sanding to leave scratches on the neck that will be on your guitar for the rest of your life.
If you have to, just take a break, and leave the neck for tomorrow. Once you get a little rest, and you get away from the process for a while, you’ll come back fresh and be able to start again. Do this as many times as you need to get rid of all the scratches.
Cabinet Scraper Alternative Method
If you’re going to use the cabinet scraper to smooth your acoustic guitar neck, it’s a pretty nice process, and you’ll only have to use one tool to be successful. Pick a couple of nice scrapers, and burnish edges on them so you don’t have to pause very often.
Work with the grain in curved sections, and be careful not to dig or press too hard so you separate the fibers. Work in broad strokes, and make sure that you’re pulling off little ribbons instead of making ground up dust.
The cabinet scraper is a one stop shop. This means you don’t have to switch grits, because there are no grits. All you need to do is keep on scraping, and eventually the surface will be extremely smooth.
See Also: How To Use A Cabinet Scraper
Coming Up Next Week
Coming up next on how to make an acoustic guitar, I’ll show you how to drill the tuning machine holes in the headstock. This may seem like a very easy process, but I’ll show you a mistake that I made, which was actually quite a pain in the butt.
Even something as simple as drilling holes can be complicated if you don’t pay attention. I’ll show you what you need to know, and you’ll be able to confidently drill for your tuning machines without any problems.
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