DIY Network

Handmade Mandolin, Part 8: Completing the Neck From "Handmade Music" episode DHMM-106

A newly made Dudenbostel mandolin gets the seal of approval from Kentucky Thunder's mandolin virtuoso Andy Leftwich.

In this final segment in this episode of DIY's Handmade Music, the neck of the mandolin is carved from a solid block of curly-maple and made ready to be joined to the mandolin body.

Materials:

Curly-maple stock
Band saw
Table saw
Instrument-maker's glue
Hand-tools (chisels, scrapers, finger-planes, etc.)
Straight-edge
Carpenter's pencil
Safety glasses or goggles

Safety Alert: Always wear safety goggles or safety glasses when
working with wood, power-tools, saws, drills, routers, etc.

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Completing the Neck and Dovetail Joinery

• The stock used to create the neck itself is a 4x4 piece of curly maple (figure A).

• With the help of a template, Lynn cuts a rough shape for a mandolin neck using the band saw. Then, again using the band saw, he slices the neck in half lengthwise (figure B). He does this so he can sandwich a decorative slice of cocobolo wood down the middle of the instrument's neck.

  Figure A

  Figure B

  
  
• Using epoxy, Lynn combines the three pieces of wood (figure C).

• After a couple of hours of dry time, he cuts away the extra cocobolo leaving the basic form for the neck (figure D).

  Figure C

  Figure D

  
  
• Later, he'll install a truss rod in the mandolin's neck. A truss rod (figure E) is a metal rod that's installed in the neck that allows for adjustment to counter the force of wood movement caused by the tension of the strings. For new, Lynn cuts the channel for the truss rod at the table saw, and checks to make sure the channel is the proper depth (figure F) He'll install the rod later.

  Figure E

  Figure F

  
  

• As seen in comparison template for the peg head, the stock for the neck isn't as wide as the finished peg-head (figure G).

• To provide the extra width necessary, Lynn glues two lateral wooden extensions -- or "ears" -- at the location of the peg-head (figure H). "To make a mandolin neck out of a single piece of wood," says Dudenbostel, "would be very wasteful because you need such a wide piece of wood for the peg-head of the instrument. So, traditionally what's been done is to select a piece of wood about 1-3/4" wide for the main part of the neck. Small ears glued onto the side of the peg-head give you that width that you need."

  Figure G

  Figure H

  
  
• Earlier Lynn cut the dovetail into the body of the mandolin (figure I). Now he has to prepare the matching cut for the neck.

• Lynn does that by placing a strip of paper under the instrument and tracing the dovetail's shape. He then cuts out the dovetail on paper to create a template. He double-checks his template by on the instrument. If this paper template fits precisely in the dovetail (figure J), he's assured of getting a good bond between the neck and body.

  Figure I

  Figure J

  
  
• With the template lying on the neck, Lynn transfers the dovetail pattern from paper to the neck's base. He then cuts the matching piece of the dovetail at the band saw (figure K).

• After a rough-cut on the band saw, he does the final fitting of the dovetail by hand. He uses hand tools such as chisels and sanding sticks to finalize the dovetail (figure L) for a perfect fit.

  Figure K

  Figure L

  
  

  Figure M

• He then checks the fit of the dovetail by dry-fitting the head and neck-piece together (figure M). "Power tools only get you so far," Lynn says of this part of the process, "Then you have to finish up by hand. I'll take chisels and small sanding sticks and go in and finish the dovetail to get a very tight fit when the neck slides into the body. You want a very strong joint right there.
  
• Next Lynn can glue the peg head veneer to the ears he prepared earlier. First he attaches the front veneer using instrument maker's glue (figure N). After drying he uses instrument makers glue again to bond the back veneer which is also cut from cocobolo.

• With a band saw, Lynn then cuts away the extra maple from the peg-head (figure O).

  Figure N

  Figure O

  
  
• Lynn can now begin the process of carving the neck to its final shape. First, with the fingerboard in place, he marks the precise location of the fingerboard onto the neck piece (figure P). Based on these markings, he rough-cuts the neck's shape at the band saw.

• Then he begins using a variety of carving tools to begin shaping the neck (figure Q). This part of the process takes several hours, divided about evenly between carving out the basic shape and fine-tuning the exact shape and surface of the neck.

  Figure P

  Figure Q

  
  

  Luthier Lynn Dudenbostel gets satisfaction by hearing his instruments played in the hands of skilled musicians. According to Lynn, he can pick out the sound of an instrument he's made -- much like a parent can pick out the voice of his or her child among a group of children.

RESOURCES :

Stewart MacDonald's Luthier Supply Shop
Website: www.stewmac.com

Luthier's Mercantile International, Inc.
Website: www.lmii.com

Pioneer Valley Luthier Supply Company
Website: www.pioneervalleyluthier.com

Kentucky Thunder
For more information on the band that appeared in DIY's Handmade Music, Kentucky Thunder -- and to hear streaming audio and download samples of their music -- visit the website for Skaggs Family Records, www.skaggsfamilyrecords.com.

GUESTS :

Lynn Dudenbostel, Luthier
Dudenbostel Stringed Instruments
Knoxville, TN