Rosettes and Purlfing

     It’s been a few weeks since the last update. The shop needs to be rearranged for a replacement bandsaw and drum sander. It’s a perfect time to get some cleaning and maintenance done. sometimes it’s important to have a less dusty shop.

     Frames, braces, tops, backs and glue create the bodies of these guitars. The braces and frames are complete, onto the tops. The same style and design will be used for each one. An amboyna burl rosette with a black white black border. First a little work to complete the frame.

     A bottom decoration is put in to hide the joining line. The inlay and wood insert are glued in. It’s a messy process.

It’s cleaned up with a chisel and sandpaper.

Next, we turn to the top and the rosette.

     Channels are routed in the cnc then inlay is glued to the outer and inner edge. Pressure is applied and a drop of glue seals the deal.

     The pieces of the rosette are routed out. To conserve space the circle is broken up into four quarters. They are tessellated in a rectangle then cut out. Double stick tape keeps them attached to a spoiler board. To be detached, heat is applied.

Glued in place. Some adjustment required.

The finished product on spruce and cedar

     A large detour to create elegant purfling ensued. Many ideas swirled for this series. The wave designs worked well for the last series. A good design, but a now comfortable technique. A new purfling pattern is desired for this set. Nature and symmetry inspire the set.

     Technical difficulties present the next challenge. The idea is to make long thin strips using the bandsaw. Then cnc the pattern.

     It can make any pattern it’s given. But different router bits used will affect the size and resolution of the image. Purlfing is not wide and looks better when in thinner strips. To accomplish this precision a 0.05” end mill bit is used.

     Small strips mean small details. Thin purfling and patterns want to break off and ruin the run.

     The strips bend around the lower and upper bouts. This provides a limit on the thickness in certain places.

     Here is the cnc at work. The wood used for the first trial was bog wood. It’s light, hard to see in this picture. It’s taped down to a spoiler board. An added problem is that the purfling can break while being pulled up.

Using the heatgun and a scraper the pieces are pried up.

One of the designs that worked.

Another design that worked.

There was limited success making these. The key design snapped in multiple places many times.

The number of strips that were usable ran out and attention was turned to finishing the bodies once again.

The back was sanded in places.

A set of back and sides were finished and glued together.

The body glued together.