Martin Guitar Kit Project Build – Part Three

| December 20, 2010 | 0 Comments

Editor’s Note: This is Part Three of our continuing series on building a Martin Guitar Kit. To start the series from the beginning, visit Part One. And now, our continuing story from author Bob Moore:

This past couple of weeks has been pretty slow. After getting the back panels joined, I discovered that I had misplaced the braces for the back. We tore the house up looking for them, but never have found them. So I have Blues Creek Guitars sending some replacements.

Also, I do not have a router bit that will fit the .060″ purfling that will be used for the rosette. I do have a circle-cutting jig that can be used with my Dremel tool, but I took the opportunity to order the router bit from Stewart-McDonald. The router is much more precise than the circle-cutting jig. Even though I don’t need that precision on this guitar, I will in the future.

This brings to mind a question asked by someone regarding Part I of this series about the tools needed to build this kit guitar. My answer borrows from Bill Cory’s book, Building Martin Style Acoustic Guitar Kits:

  • Guitar Mold – there are many kinds – Stewart-McDonald sells their kit with an internal cardboard mold. I did not like that idea, but some might find it handy. I built my first mold out of 3/4″ plywood, using the pattern they provided. The Martin kit did not come with a mold or a pattern, so you will need to make or buy your own. If you build your own mold, lay out the pattern of 1/2 the guitar shape on one piece of plywood and saw it with a band saw or a Skil saw. Get it as close as possible to the pattern. Work it until you have it as good as you can. Then cut out the other pieces. Use the first piece as your guide and use a router with a flush cutting bit to make the other pieces exactly the same. Then stack 3 pieces for each half of the guitar. They can be glued or screwed together. To join the 2 halves, you will need clamps or hinges or blocks of wood. If you are going to make more than one guitar of a certain body style, a store-bought mold might be a good investment.
  • Saws – a small band saw is nice to have. It doesn’t have to be high-quality unless you intend to re-saw sides/backs/tops. Mostly I use it to cut and shape braces and other small parts. A razor saw, or other small sturdy saw, even a coping saw would work as well.
  • Drill and Bits – the Martin Kit does not have the holes for the tuning keys drilled in the head stock, so you will need the drill for that. Also, some kits don’t have the position dots drilled out.
  • Laminate Router and Bits – this is for cutting the binding/purfling channels. A Dremel tool might work, but they don’t usually have enough power to cut channels in one pass. A laminate router for about $80 or so is a good investment. Mine is a Bosch Colt.
  • Jig – Along with the router, you will need a jig to cut the channels. I got mine from Kenneth Michael Guitars. They sell a number of molds and jigs as well as kits.
  • Ruler, Straight Edge & Square – A 36″ ruler and a good straight edge, about 24″ long, can be used to set the location of the bridge. There are jigs that will make this easier. The straightedge is good to have to check the neck angle. You lay it along the fretboard with one end above the bridge location, and measure the height of the straightedge over the bridge. It should be within 1/32″ above or below the bridge. A 6″ ruler with 1/64″ increments and a square are needed to check the sides.
  • Plastic-Head Hammer – For fretting, a plastic-head hammer is good, but you can also get by with a regular hammer. Just cut a plastic coffee can lid into small pieces shaped to the hammer’s head and super glue 2 or 3 pieces to it.
  • Files & Nippers – A set of small files of different shapes is needed to shape the ends of frets. Other tools for fretwork include nippers to cut the frets to size. Fret tang nippers are used for a bound fretboard. The tang is the part that goes into the fret channel. On a bound fretboard you want to cut the tang off at the end of the frets so that the fret itself will lay on the binding. You’ll need a fret crowning file to true up the top of each fret. Do some research and you can make this type of file. Nut-slotting files are very handy. They are set to the thickness of each string so that the strings sit in the slot correctly. You can get by, as I did on my first, with very small files. But I later bought them because I was not happy with my nut slotting. Sometimes you have to bite the bullet and buy the right tool.
  • X-Acto Knife – or similar type of knife is essential to have on hand for many small cutting needs with a sharp, narrow blade.
  • Palm or Random Orbital Sander – There’s a lot of sanding on guitars, and they make for quicker work than doing it by hand.
  • Clothespins – Earlier in this series I used clothespins to glue the kerfing to the sides. Some people put rubber bands on them to create more squeezing force, but I’ve not found that to be necessary.
  • Chisels & Wood Plane – at a minimum you’ll want a 1/2″ and 1/4″ chisel for shaping braces. A small wood plane is also helpful for shaping braces, but not absolutely necessary. I’m buying a small finger-plane for this type work but I could do without it.
  • Small Vise – I bought one specifically for shaping nuts and saddles.
  • Scrapers & Sand Paper – Have sandpaper from 120 grit up to 2000 grit on hand. I also use Micro Mesh cloths from 1800 to 12000. The Micro Mesh is good for shining up frets as well as guitar bodies. I sand from 120 to 400 on the guitar body and neck before it’s ready to finish. Then I wet sand the body and neck during the finishing process from 600 grit to 2000, then Micro Mesh from 3600 to 12000. At that point, I use some polishing compounds and the finish is done.
  • Clamps – an assortment of cam clamps, spool clamps, spring clamps and bar clamps. The more the merrier.
  • Rubber Bands With the type of guitar mold I use, rubber bands are needed for securing the top and back to the sides.
  • Go-Bar Deck – Some people use a Go-bar deck for many clamping needs: gluing braces, clamping tops and backs to sides, etc. If you’re not familiar with these take a look at the StewMac Version
  • Masking Tape – You’ll use this for binding/purfling and for masking off the bridge and fretboard extension over the body. Painter’s tape also works well.
  • Glues – You’ll need a variety of glues. LMI makes an Instrument Maker’s Glue. I use Titebond for all wood to wood gluing, super glue for some purfling or rosette materials and Duco cement or WeldOn for gluing plastic bindings.
  • Finishing Supplies – There are many finishing methods. You’ll need to seal the wood, fill the pores, and put on top coats. I’ve found that the finishing materials cost me about $100 or so.

The list above works for me but may not be complete depending on how you tackle various jobs. And here’s a tip – be sure your tools are sharp. I have blood on both my guitars so far as a result of dull tools.

Follow safety precautions for any tool you use and use scrap to test out finishing products. When you get to assembling parts, first dry fit them without glue to make sure you have it right. Don’t rush.

Glue, except for Super Glue (which is almost immediate), will set up fairly quickly, but don’t hurry – just lay down the amount of glue you can work with in a short time, and be accurate.

Now, on with the building. Since I don’t have parts or tools to do the top or back, I turned to the fretboard. The Martin kit’s fretboard is Rosewood. It has the fret slots already cut. The holes are drilled for the markers. Here (Photo 1) is a picture of the fretboard and the position markers close to their holes.

Photo 1 – Martin Fretboard with Position Markers Ready to Install

To the right of the fretboard is a tool I didn’t mention before. It’s a radius block with a built-in 16″ radius. I use spray adhesive to attach sandpaper to the block. You can see the sandpaper on the radiused block in Photo 2.

Photo 2 – Radius Block with Sandpaper Attached

To install a marker just put some super glue in the marker hole and push the marker into place with a knife blade. Be careful not to glue your finger to the marker or the fretboard. To level the markers to the fretboard I sand using 120, 220, 320, and 400 grit paper and then remove the super glue residue. The result is shown in Photo 3.

Photo 3 – Position Markers Installed and Sanded

Next, I cut the fret wire for each fret with my end cutters (fret nippers), and hammered the frets into place. To do this, I created a very sturdy surface for hammering. On top of my large granite block, I put another piece of granite that was 4″ by 24″. Starting at one end of the fret, I knocked them into the slot with the plastic head of the hammer. There was just enough fret material to do the 20 frets. I had about 3″ left over. Other vendors usually have more wire than that. If I had bound the fretboard and made mistakes cutting the tangs, I might not have had enough.

Here’s the result in Photo 4. You can see the tools that I used above the fretboard. The granite is not needed. Just use a concrete floor as a sturdy surface.

Photo 4 – Frets Installed

Hopefully the items I need for cutting the rosette and bracing the back will arrive soon. If so, I’ll leave the fretboard alone and get going on closing the box. An internet friend of mine sent me some pieces of Koa to use for a headstock and tail wedge. They look enough like my binding to really make this guitar look good.

Category: Acoustic Guitar Kits

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