Building a guitar in 24 days - photostory

[Martin_Nut]

OC1 - awesome. Enjoying the heck out of this thread. Thanks!

[Cornerstone Guitars]

Originally Posted by OC1

Gluing the Heel block

Looks like you are making great progress! Very cool!

One quick question, is it me or did you use a different neck? The first picture's heel block is different than the others... also, the 3rd picture also shows a one piece neck and not a glued on heel.
No big deal, just curious.

Keep up the good work.

[OC1]

Adjusting neck and preparing for body finish

This step is less visual and more dusty - I am spending most of the time sanding down the guitar body. I already scraped sides the other day with a scraper after I put binding so they are fairly clean from glue and flat. Now I am going to sand it down by hand to remove any scratches. Sides are easy as the sharp scraper did a very good job to smooth them out. For bottom I used the ordinary orbital sander - the guitar amplifies the sound of the sander like 10x. It takes some time to remove all the sanding scratch marks from the bottom but it is fairly mindless job.
I do the same for top but more gently and use hand much more than the orbital sander. The spruce is far softer than the wood of binding and rosette, so this has to be taken into account.
The other thing is to put a nice bevel on the binding (I hate sharp edges on a guitar binding) sound hole and soundport.

The next very important step is to adjust the neck to the body. I already adjusted it previously before gluing fingerboard so the angles are roughly ok.
But this step must be done properly. The goal is to have all the angles of neck-to-body correct, the dovetail fit snug and no gaps where the neck meets the body. This is done with chisels, sanding paper and shims. Sounds simple? Well as you adjust for one setting, the other settings are then changed as well... and for a novice this become really frustrating. Almost half of the day had been spent on this. I am pretty sure a good luthier can do it much faster...

Here is pictured one of the few processes of fitting the neck to body and remove any gaps with a piece of strong sanding paper.


Tomorrow I will start putting a finish to the top and neck so we are going to cook our magic potion.
There is not going to be any spraying, no spray booth, no fumes - I am going to do a French Polishing.


Some people may be surprised to see French Polishing steel string guitar as the shellac is known to be more delicate than the more common spray finishes and it is therefore more accepted for classical guitars.

But I am not making a campfire guitar or a kit guitar - I am making a delicate high-end instrument from scratch and french polishing is just the right thing for it. It has many benefits: simple setup (no spray booth), it is quick - almost no drying time - the guitar can be gently handled almost immediately and it is way simpler to repair any scratches later, right at home.

But as any french polisher knows very well, the shellac is "she" and has mood swings and the moment you think you already know how to handle "her" she will show you who is the master.
But more about this later.

[OC1]

Originally Posted by worshipguitar

One quick question, is it me or did you use a different neck?
Keep up the good work.

Peter, you have an excellent eye! I was waiting who would catch this. Yes, indeed I made two necks. First was sapelle and during routing of the head a corner badly chipped out (I did go the right direction but maybe had too much material for router and didn't cut too close on bandsaw) but I was able to find the piece and fixed it. When I was routing the repaired part, the neck chipped out on the very same spot even deeper but the chip was nowhere to be found this time! I simply gave up on that as a second repair would be simply much more work than preparing new neck. I quickly took a block of mahagony and did all the preparation steps again, flattening, gluing veneer and in 60 minutes I was back on track (I used polyurethane glue for veneer this time to save time). But this time I didn't route the head, I was just too scared - I simply cut close to the line on bandsaw and then used file and sanding blocks to finish it. It took longer than routing, but I felt much safer.

[220volt]

Probably one of the most useful and fun threads I've ever subscribed to.

[patticake]

i completely agree

Originally Posted by 220volt

Probably one of the most useful and fun threads I've ever subscribed to.

[OC1]

It is the time to start doing french polishing

But not so fast, first we need to fill the grain/pores of the wood. If we don't then we wouldn't be able to make a mirror like finish on the guitar - the pores will show as a hundreds of little craters. Also not all wood need to be filled, the top is not going to be filled, spruce or cedar doesn't have open pores. But our back and sides (and partially neck) are open-pores woods.

There are many way to fill the grain, I used pumice stone. This has been used for hundreds of years as a abrasive before sanding paper came that not only sanded the wood but actually also filled the pores on the same time.
Some people use also epoxy as filler, but I am trying to stay away from any toxic materials - I like my health as it is.
The pumice stone has also mixed some pigment into it (different for neck and for back). It is also important after filling to properly sand it to remove any pumice otherwise it would show as a "mist" or dirt.

Here I am filling the neck.


The first thing I am going to french polish is the top and the neck because soon I will be joining them.
I am not going to talk much about French Polishing. It is a different beast - it is a slave to no one and works differently from anything else.
You use a piece of wrapped cloth which is called "fad" or also "muneca". You put very, very little of the shellac on it and then polishing around and around for maybe 30 minutes or so. Then repeat to build the shellac up. But French Polishing works in reverse - less is more, slower is faster, avoiding part will fix it, the dryer it is the more will be added etc... everything you know about any type of modern finishing will need to be forgotten.
There is no single good way to do French Polishing, but there seems to be thousands of bad ways.

I had a great, great start, but as soon as I thought I "got it", I was ruining everything. You never rush with french polishing, as you start rushing, you will be back at square one - sanding it down and starting over again.

Here is the top, beveled and french polished. There will need to be few more sessions on it. The sides and back are not polished yet as the top and neck is priority now.



and the neck:


All this went pretty quickly but I will be doing it here and there again (and probably ruining it) over the course of next few days.
The good thing about FP is that tomorrow I can do back and sides without much danger of ruining the top as it will be pretty resistant to imprint. When you come to think about it FP is a gread way for one-off special instrument as it doesn't hold you down stuck waiting.
(With spraying, you would need to let it cure for maybe two weeks without touching it before any handling)

Now if I make serial guitars in a factory setting - FP would not fit to workflow too well - it is easier to simply hang all the guitars in spray booth, spray them, sand them down, spray them again, sand them, spray them and then let them cure for two weeks while making other guitars. But for one-off guitar FP is a godsend as there is no dummy time waiting and not doing anything.

Tomorrow will be still French Polishing , and day after that and maybe also another day. I am at day 16 of the 24 day timeframe which is just right on the track with day or two to spare for fixing problems I will surely create.

[Broadus]

Great stuff, OC1! The days are passing quickly, but you're putting a lot of time and effort into those days. It's looking really good.

Bill

[OC1]

A few words about shellac and french polishing. You could see we were cooking shellac. Lot of sites that sell shelac would tell you to disolve it in alcohol and use it. You will never get anywhere with french polishing this way.

This is the same as saying you make a cookie by mixing flour and water and then bake it. Doesn't work that way.

There are hundreds of ages old recipes for making shellac as many as for making a cookies, and none will tell you just to mix alcohol with shellac. There are always more ingredients to put in it (resins), various way to mix it, cook it multiple times, decant it, filter it etc...

There is no single magic recipe for shellac as there is no single magic recipe for a cookie. You have to talk to people and/or look on internet for good recipes from people who are actually using it. There are also books on wood finishes, much like a food recipe books. This is the proper way to do it and it makes all the difference between an unedible cookie-like substance and a delicious cookie.

[OC1]

Continuing French polish

Here are FP sides already getting shiny but this is about 30 min of french polishing, so there need to be much more done on it.


A detail of the binding - the sapelle under the shellac get 3 dimensional qualities and look copper-gold.


A detail of soundport


The French Polishing can be extremely rewarding when it goes as it should (and extremely frustrating when it doesn't)
Here is a detail of the back.
The rosewood was pretty porous and I did a great job filling the grain with pumice.
I did it more industrial-style - instead of trying to fill the grains up all at once and not miss any pores I first filled it up with pumice, then sanded out the pumice from surface then used a bit shellac on top. Waited 10 minutes, sanded it all down and repeated with pumice and the whole process. I did this 3 times after which the back become one glossy surface.

The thing sticking from the guitar where neck should be is a handle that is fitted in the dovetail and secured with a nail for easier manipulation of the guitar.

At this moment I can say I really like the colors and the combination of the wood.

This whole day was about pumice and french polishing. If I can say, I didn't like the part of filling the grains as this is a dirt job that you have to clean pretty throughfully, but I liked the french polishing sessions as they went pretty smooth today. And you simply sit down (or stand up) talk to people, listen to music and do the polishing.

Tomorrow I will continue adding few more sessions on sides, back and top, but I will also take a break and start making bridge.

[Broadus]

Impressive as how the French polishing is turning out.

Bill

[Fliss]

I love the way the French Polish brings out the beauty of the wood, and the neck profile looks so smooth I just want to put my hands on it. Very nice!

Fliss

[OC1]

Yes, I like the neck profile too - but obviously I made it the way exactly how I like it which is the benefit of making your own guitar. When I was carving it I often took it in hand in playing position, closed my eyes and feel it for smoothness and shape with which my hand would completely agree. When you working with wood, eyes are not always best way to judge things. For example neck may look perfectly smooth but when you use fingers with light touch you can far better discover some flatness or bumps on few places here and there.

[acousticjazz]

Once again OC1, this is an amazing thread, I'm going to have to go back to the beginning when it's all finished to see the process from start to finish all in one cup of coffee The french polish is looking great, can't wait to see the finished guitar, great job, and thanks for creating this wonderful thread!

[OC1]

While I still continue on the french polishing, let's have a break and make a bridge.
This isn't a big job, unless it is going to be some very specific non-symetrical bridge. I am going for roughly the martin type of bridge, but then I will bevel and round all edges as I really don't want any sharp edges - I usually play travis style with my hand resting on the bridge.

The bridges are cut from a big piece of mahagony, then I routed a slot under angle (same as Martin)


Then drilled holes for pegs.


Bridge was shaped on a band saw close to Martin style


Then using a router and a martin style template the shape was cloned.


The rest was using sanding belt to shape it very close to Martin style. The belt on sander goes in a loop and one of this round edge was used to make the smooth flute on the bridge sides with using a simple setup.
(Where the bridge goes thin from edges then jump up in a smooth curve thicker where the saddle going to be).
Our setup was very simple jig using a wedge held by few clamps to keep the gap between the wedge and the sanding belt constant, but I had also seen elsewhere on internet a spindle sander put on a drill press with some simple table (luthiers friend).

Some builders would shape the bridge then glue it and after it is glued they would route the slot into it in correct position. I am not quite sure why or what is the benefit (maybe someone can shine light into this). I think keeping router as far away from a finished guitar as possible has far more advantages.

There are not many places on a guitar where a guitar maker can put their own signature look. So most guitar makers would put their own unique design into head shape and to the bridge shape and then stick with it.

I never paid too much attention to the bridge shape previously, but in fact steel-string bridge is the easiest place how you can recognize the builder (the more expensive instruments would usually not have the builder name inlay on the head as to more emphasize the "custom one-and-only" look instead of a "stock" look)
In classical guitars the bridges are kept fairly conservative so the classical builders would jumpt through hoops to make their head unique (yet still very conservative to casual observer) by carving their very own signature heads. This is the way how professionals briefly look at a guitar from distance and say, oh, I know the builder, without looking into a soundhole.

As for tomorrow, there is not going to be any more french polishing of top after today. Tomorrow I am going to put a neck on so all french polishing of top should stop today and let it cure through night. The sides and back don't matter - french polishing can continue on those after the neck is on. (Not that I have any energy for that left)

After neck is on there are only few more steps to be done as we are nearly at the end of our jurney - we need to glue the bridge, shape fretboard, cut the frets, bang them on, make saddle and nut, put machines, string it and set it up. After everything, that just sounds like a walk in the park, doesn't it?