This is How to Make an Acoustic Guitar – Part Thirty Six – Finishing. In this part of the series I’ll show you how to apply a world class finish by hand, as well as several finishing tips and tricks that will make the process easier. Enjoy.
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Finishing the Acoustic Guitar
If you’ve never finished a piece of woodworking before, let alone an acoustic guitar, you are in for an incredible treat. You are going to literally watch a piece of wood transform into a completed project right before your eyes.
This is an amazing experience. It’s seeing a transform into something totally different, because the change is so dramatic. Especially with a hand applied finish, it’s an amazing sight to see.
Unfinished wood, even great examples of unfinished wood, pale in comparison to their finished counterparts. The look is deeper, and more colorful. Again, if this is your first time, be ready for an awesome experience.
If you missed last week, here is How to Make an Acoustic Guitar Part 35.
Selecting the Perfect Finish
The first hurdle that you need to get over is selecting the perfect finish. This is going to vary depending on what you’re comfortable doing, and the equipment that you have access to. Remember, you don’t necessarily have to spray the finish.
There have been many amazing pieces of woodworking that were finished by hand, using very primitive techniques. They still look awesome today, and you can do the very same thing in your shop without any expensive equipment.
You can also find a middle ground, and finish using rattle cans. Before you start laughing, these aren’t the same bottom shelf cans of lacquer you find add a home-improvement store. For finishing an instrument, do you use instrument grade or furniture grade lacquer.
These cans can be $8 to $15 each, and the product inside is the same product that you would shoot through a gun, just on a smaller scale, and self-propelled. Anything from Mohawk or Behlen is a good place to start.
Finally, if you want to invest in the equipment to professionally spray lacquer, then feel free to do so. I’m not going to stop anyone from spending money to enjoy their hobby, just know that you don’t have to in order to create an amazing finish.
See Also: 10 Step Guide to Wood Finishing
Play to Your Strengths
The bottom line for choosing which finish you are going to apply is to play to your strengths, and choose something that you know you’ll be comfortable doing. The more comfortable you are, the better the finish will turn out.
This also means don’t jump in with both feet on something that’s brand new that you don’t understand. In a case like this, do a little bit of practicing until you have mastered the skills before you potentially sacrifice your instrument.
If you are really comfortable applying a finish by hand, then choose a finish like a true oil, armor seal, or something similar. These are all fantastic products that can be applied with clean cotton cloths, and they look professional when you’re done.
Again, no matter what you finish with, do something that you’re comfortable doing. Not only will you feel better during the process, the calmness will translate into better results, and a better looking finished guitar.
Apply Very Thin Coats
Finishing is an interesting part of woodworking. In itself, it’s a completely different skill, but it requires woodworking in order to even be used. Though there are a lot of things to know about wood finishing, there is only one really big thing.
No matter what you do, applying thin coats of finish is always a good idea. Whether it’s a hand finish, or a spray finish, thin coats will always serve you better than thick coats. This is a fact of finishing, and something you can use to your advantage.
Thin coats are very good for your finish, because they prevent you from having thick and thin areas on your piece. They also prevent runs, sags, and other defects that come from applying too much product.
You make a lot less mistakes applying thin coats, and you’ll have to do a lot less work on the back end after the piece has cured. Even though it may take a little longer at first, because you need to apply more coats, in the end you’ll actually save a lot of time.
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If this isn’t your normal way of finishing, pick up clean cloth, and practice applying coats of finish so thin that you almost feel like you’re just making the surface of the wood damp. I promise, you’ll love the way it looks in the end.
See Also: The Secret to Wood Finishing
Optimize the Area for Drying
Another thing that you can do to help the process is to optimize the area where the guitar will hang between coats for the best possible drying. When you buy a finish from the store, the drying time can be a little misleading on the label.
In order to get the lowest time possible, finish manufacturers do their tests in rooms with zero humidity and a warmer temperature than normal. You can use some of those tactics to your advantage by finishing in a warmer room with low humidity.
You can also create some air movement in the room with the fan, and good ventilation through either windows, doors, or both. This keeps the air circulating and fresh, and encourages the finish to dry better.
See Also: How to Speed Up Wood Stain Dry Time
Applying Coats of Finish
Each finishing product is going to be a little different than the next, but in general you only want to apply as much finish as you need to protect the wood, and bring out the color. Typically, this is less than you might think.
It’s unfortunate that so many mass produced instruments look as though they were dipped in lacquer and then just allowed to drip dry. This looks awful, and it really takes away from the natural beauty of the wood.
The manufacturer could probably do just as well with about half that thickness of lacquer, or maybe less. The reality is that you don’t need a ton of lacquer to protect your instrument. If you handle your instrument well, you need very little in fact.
Use this advice, and only coat your guitar with enough lacquer to protect from the seasonal changes in humidity, and bring out the beauty of the materials. Anything after that is too much, and anything less is too little.
See Also: How to Choose the Best Wood Finish Spray
Allow Time for the Full Cure
Most wood finishing products take at least several days to a couple weeks to reach their full cure. This is where absolutely all of the solvents have evaporated from the finish, and it’s all solids on the surface.
Whatever time is specified by the manufacture of the finish you are using, give that full-time to your finish before you handle the guitar. If you don’t, you run the risk of easily denting, scratching, or printing right on your finish.
This is awful, because you’ll essentially have spent so many hours of your life making something, and then ruin it at the last minute. It’s just not worth taking the risk, especially only to save a few days of waiting.
I’ve been in your position many many times. Even though it’s very tempting to just bring that guitar in because it feels dry, just leave it, and let it fully cure. I promise, it’s definitely going to be worth the wait in the end.
See Also: Acoustic Guitar Making For Beginners
Coming Up Next Week
Now the guitar is fully finished, it’s time to install the hardware, and string it up. This is a fun part of the process as well, and that’s where you finally get to hear what your guitar is actually going to sound like.
A fair warning, in the beginning your guitar is not going to sound very good. However, in the immediate hours that pass as you play, the guitar will begin to make changes and sound much better than it did at first.
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