Archive for the ‘ Guitar building ’ Category

Stage 13) headstock work

For the advanced technique in lowering the headstock to the desired thickness, check out the ebook Building Necks at jcsmi.com
Using the band saw in conjunction with the fence, set the thickness just over the headstock thickness. Advance the headstock with the back of the headstock sliding flush to the fence. Stop the cut with room to intersect the cut with another angular cut. Make sure to leave enough room to spindle sand a transition to the new face of the headstock.
Block sand top face of headstock with respective sandpaper starting with 60 grit and ending up with 150 grit.

Stage 12) Fretboard radius shaping

The next step is adding the radius to the fretboard. We need to use the drum sander to bring the neck down to the desired thickness. I use 1 inch from the back of the neck to the top of the fretboard. Now we will need plenty of chalk, in a variety of color. The reason for this is my use of multiple colors of fretboard also neck materials. Chalk is applied after every pass on in the sanding and machining process so you can never have enough. a radius gauge and a belt sander. Start by carefully removing wood from both sides of the fretboard and check the surface the radius gauge often. Apply more chalk on the fretboard as the belt sender removes the wood. Rock the neck back and forth over the belt sander trying to keep from removing the wood at the centerline. Using the radius block and 60 grit paper, bring the radius to match the radius template. When matching the radius, use a sanding pad approximately 3/8ths thick in your palm and rub 80 grit up and down the fretboard till smooth.

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

Stage 8) Slotting the fretboard

After we have the fretboard cut out and thickness sanded to size, it is time to slot the board. For small jobs, I use the fret slotting saw, fret slotting template and miter box. There is a formula to figure out the fret spacing for odd scale lengths. Try the
fret caculator I found online. I used this formula for a couple of neck jobs with odd scale lengths. For Building your own practical fret slotting machine, please refer to my eBook soon to be published. As my orders for necks started to increase, my ability to manually slot fretboards became impractical. Take it from me, I wanted to manually slot each neck but the miter saw blade seems like it expands as it heats up from friction and gets harder and harder to saw as the slot gets deeper. The saw actually feels like it is a slip fit when the blade is cold and a press fit and pinched in the slot when hot. Not sure if this is really happening, just what it feels like. I even tried some types of blade lubrication with no luck. There is much detail when it comes to slot depth. In a perfect world, it is nice to have .010″ depth below each fret tang. As the radius changes down the neck, the flat bottom slot cannot match the effect of the taper and radius at the fretboards edge. I will discuss tips and tricks in detail in the eBook. This is beyond the scope of this blog.
Thanks for checking out this blog and please join my newsletter and pass this blog along to anyone you think may be interested in it or my product recommendations. I don’t want the downstream builders to suffer my trials along the road to building their dream neck.

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Stage 7) Making the fretboard.

Select a premium grade of wood for the fretboard. I bring the stock down on my drum sander so after gluing, my fretboard and neck blank thickness will be 1.010″ when finished. I will explain a little later in the backside routing process the need for the .010″ extra stock. Before I route the radius into the fretboard I use a Jet 16-32 Drum Sander and take the stock down close to my total neck thickness using 80 grit sand papersand paper. A great tip for loaded up sandpaper is using Gorilla Tape to stick to the buildup. after several stick and re-sticking applications, you will see a major improvement in stock removal. Using the fretboard template, I draw out the fretboard shape on your stock. For darker woods I use a Prismacolor Premier Colored Pencil, True Green Lead. For some reason this color stands out on the widest variety of wood species. On maple, I just use a mechanical pencil with 0.5mm or 0.7mm lead . Next, we put the centerline down the Neck.

Hollywood Series in Python

Hollywood Series in Python

Stage 6) Making the fillet for the truss rod channel.

Making the fillet for the truss rod channel. I use a piece of flat stock scrap from the maple fretboard blanks. I saved the first working fillet and use as the template for all other fillets. The use of a .03mm mechanical pencil helps in getting as close to the original as possible. Gently rotate the led of the pencil, topside of led towards the original template. Now I take the maple stock with fillet outline over to the band saw. I cut as close to the pencil mark as possible with out crossing into the fillet. If there is more stock than needed, I head on over to the belt sander and slowly remove stock to the pencil mark. The next step is to put the semicircle at the back end plan view. This is done to match the truss rod trench near the heel of the neck. Lastly, I drum sand the final thickness of the fillet till I have the correct fit into the truss rod trench.

 

Brazilian and Cocobola by JCSMI

Brazilian and Cocobola by JCSMI

 

Stage 5) Building the truss rod

Use 10-32 threaded rod cut to length. Use a tap and die set to clean up the threads that will be used with the adjustment nut. Be careful not to cross thread the 10-32 threading. Next we need to make the anchor slug. Make sure it is thick enough to have enough thread engagement. Find the center of the slug and use a center punch to indent the center point. We are going to drill a through hole that will allow us to cut 10-32 threads into the slug. Then we screw the 10-32 threaded rod into the end of the slug. The eBook following this blog will have more detail on making the truss rod. I use plastic straws that are cut to length to keep the glue from getting to the treading. Using 2 straws for this process works out perfect. Tape the straw joint with Scotch Magic Tape to keep the wall of the plastic straw as thin as possible. Vaseline the threads for the adjustment nut and the bearing face of the nut to eliminate unnecessary friction when adjusting the truss-rod nut.

Black Cherry Vibe series

Black Cherry Vibe series at JCS Musical Instruments

Stage 4) Pencil a centerline and prep for truss rod install.

Once you have the neck blank cut out, you need to put a centerline on the blank. This centerline will be used to center the fretboard when gluing and also be used to prep for truss rod installation.
*We are going to discuss how to install the single action heel adjust truss rod here.
We need to drill an adjustment nut hole into the heel of the neck. Before we do this, I drill a reference hole into the top side where the nut adjustment hole will stop. This allows me to insert a single action trust rod into the nut adjustment hole so that I have a visual inspection of my trust rod passing through the adjustment nut hole and lining up with my truss rod centerline. I use a special jig with my router to route the single action truss rod channel. The jig routes a curved channel in the side view. This allows for a curved fillet of wood to be inserted and glued into the channel after the truss rod is installed. A tee slot is then routed into the neck blank near the nut end for the anchor slug of the single action truss rod. I will try and show photos, dimensions and illustrations in an eBook when finished with the building instructional on this blog. Thanks for following! Jim at jcsmi.

Guitar by RAMM Guitars, Neck by JSCMI.