Archive for February, 2012

Stage 11) Neck radius process

This is one of the most critical parts of the neck build. The neck has to feel right in your hand. Take the opportunity to check for the correct fit in your hand often in the shaping process. In doing this, your neck will give you many years of enjoyment.
The first step in the process is to belt sand the sides of the neck. The profile work we did in Stage 11) will leave the sides close but not as flat and square as we need them to be. Once they are flat and square, use the transition templates to trace the line on the back of heel and back of headstock. The lines represent the shape of the flats that have to be preserved when shaping the back of the neck. For the manual removal of stock, use an aggressive rasp file and start by long angular strokes. Using a contour gauge, press down on the back of the neck at the first fret and compare to the curve you are trying to match on the reference paper. Reset the contour gauge and take the second reading at the middle of the neck and compare to the curve you are trying to match on the reference paper. Then reset the contour gage and take a third reading at the 12th fret and compare to the curve you are trying to match on the reference paper. When you have the back of the neck close to the shape you want, use the palm sander with 40 grit sanding paper. Using long strokes back and fourth, remove the rasp filing marks and get as close to the feel you are looking for on the backside of the neck. Check out the ebook for details on how to use power tools to aid in your stock removal process. For the transitions, use the 4 in one file at the heel. For the headstock, use the round file. Shape till comfortable and flowing in appearance. It pays to have a reference neck to look at. Finish using sand paper wrapped around soft sanding cylinders.

Stage 10) Profile shaping

After the clamps are removed from the work we did in Stage 10, it’s time to mount the neck to the wooden template using two way tape. Use clamping pressure in order to have a good bond between the neck blank and the wooden template. I use the 3 inch Robo sander inserted into my floor mounted drill press to sand the profile of the neck. The wheel of the Robo sander rides on the wooden template and the sanding drum removes the extra stock we left in Stage 3. When the 3 inch sander has removed all it can, I take out the 3 inch Robo sander and finish up the neck with the 1 inch Robo sander to clean up the tighter curves at the headstock. In Stage 12, I will discuss the neck radius process. Stay tuned! Jim at jcsmi.com

Acoustic fretboard

Acoustic fretboard By JCS Musical instruments

Stage 9) Gluing the fretboard

The radius in the fretboard will be added after the fretboard is glued in place. Now take the trussrod we made in Stage 6) and slide into truss trench pushing through the hole we drilled in the heel and add the washer and trussrod nut. For this next stage we are going to use Titebond wood glue. I prefer this glue because of the ability to heat the neck in the future if the neck needs any adjustment in curvature. I will talk more about this in the future either in the blog, newsletter or eBook. The repair tips show how the JCSMI Crossbow 2 and the JCSMI Hammerhead can help in this process. I like to wipe some Acetone on the glue faces of both the fretboard and neck blank using a lint free rag. I use a 2″ putty knife to spread the glue. Use a soft paintbrush to dust off the glue faces. Lay the fretboard on its backside an layout about a 10″ bead of glue. Use this glue first to lay the fillet in. Take the fillet and lay both sides of the fillet in the glue. Now press the fillet into the truss rod channel and locate it for final setting. Then spread out the glue on the backside of the fretboard until it is complete covered. Apply a bead of Titebond from the heel of one side of the truss rod trench down toward the nut area and around then back down the other side and end at the heel. Now press the fillet into the truss rod channel and locate it for final setting. Take the putty knife and smooth out the glue evenly on the wood blank. Line up the fretboard and press down and check to make sure the center lines are lined up. Hold down and press out the extra glue just using your hands for the next minute or two. Next get 16 adjustable clamps. We also need two pieces of flat wood cut close to the shape of the fretboard to sandwich the neck when clamping. We also need two strips of wax paper on the top and bottom of the neck to prevent the neck from sticking to the wooden culls used to generate the clamping pressure. We need to start by using 3 clamps to set the fretboard. Lightly screw one in the middle then one on each end. Now place one clamp on each side of the neck starting near the center of the neck, then 2 more from side to side working toward the headstock. All 8 clamps should be equally spaced on each side of the neck. The pattern will look like this : : : : : : : : when done. After last 2 at the nut location, start back near center and work your way towards the heel. Make sure your centerlines do not move. When all the clamps are set, go back to the center two and snug up the clamps working your way towards each end. The glue should be running out evenly around the whole fretboard.

Flame Maple dot in Wenge at jcsmi.com

Flame Maple dot in Wenge at jcsmi.com