HD28 Kit - First Build

[Rick S]

The finished dimensions of my HD-28 (including top and back) are 4 7/8" at the tail end and 3 7/8 at the neck end. From what I understand, plus or minus a few fractions of an inch is not critical, and if I'm wrong about that someone will correct me.

David L

Thanks for the information David. It sounds like we were real close on the final dimensions. Stay tuned for some pics and something that may be a problem.

[Rick S]

Here are the pictures I took while radiusing my sides, gluing the neck and tailblock and gluing in the kerf.

[Rick S]

Close up of the jig showing the reference lines I drew for where the end of the fingerboard and the front and back edge of the bridge location. These lines were used in radiusing the top to make the ends domed but the middle between the end of the fingerboard and the bridge flat.

[Rick S]

Reloaded my sides in the mold using the surface of my work table. I didn't have a 1/2" machinist parallel like John uses so I used some 3/4 oak that I had from a previous project to provide a uniform spacing from the mold to the top edge of the rims.

[Rick S]

Centered the mold in my jig by inserting 1/2 inch dowel pins through the holes that I drilled in the mold and lining them up with the 1/2" holes that I drilled in the jig. I used the same piece of oak for spacers that I used to load the mold.

[Rick S]

I started radiusing the back side of the rims first with a 16" foot radiusing disc that had 80 grit sandpaper affixed to the concave side of the disc. The disc came with a 1/4 inch hole predrilled in it. On John's recommendation, I used a 1 1/8 hole saw bit to enlarge the hole to fit over the 3/4 in nipple on the jig.

To start the radiusing procedure, I put white chalk on the edge of the rim all the way around. My goal here was to evenly remove the chalk. I pulled my work table away from the wall so that I could get around 3 sides of the table.

[Rick S]

I rotated the radiusing disc back and forth, or as John puts it ...I "drove the bus", unit all of the chalk was removed. During the process, i checked frequently to make sure that the chalk was being removed from all locations. To keep from sanding too much in one area, i gradually moved around the jig rather than standing in one place.

Incidentially, I saved the Indian Rosewood saw dust in a baggie just in case I might need it at some point in the future for some inlay filler.

[Rick S]

With the back side of the rims radiused, I turned the mold over so that I could radius the top sde using a 28 foot radius disc. The disc has a flat side and a concave side that each have 80 grit sandpaper. The first step is to true up the top edge using the flat side of the disc. I put chalk all the way around the edge, put the flat side of the disc on the jig and drove the bus until the chalk was removed. I checked often to make sure that the chalk was being removed evenly. I also checked that the height was consistent above the mold all the way around.

[Rick S]

After the top edge was trued up, I marked the edge with chalk around the upper bout and lower bout without putting any on the middle. My goal was to radius from the back of the bridge to the end block and from the end of the fingerboard to the neck block ... leaving the middle flat. I intentionally extended the chalk beyond my reference points. This was so that I could tell where to stop and make sure that I left the middle flat. I used the concave side of my 28 foot radiusing disc to remove the chalk up to my reference lines (end of finger board and back side of bridge).

To finish up this process, I turned the disc back over to its flat side and made a few passes at flattening the area above the neck block. I then pressed down on the disc just above the neck block and, while holding the disc in this position, I checked to confirm that the disc was raised up above the tail block end about an 1/8 inch. And it was. This was an initial check on the geometry of the guitar which, in theory, will give me a 1/2 inch gap between the strings and the top at the bridge location.

[Rick S]

It's late ... more pics to follow ... maybe tomorrow.