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I've seen some rosette purfling mosaics with circle or dot's in the mosaic. Since most mosaics are built from logs or stacks, for the life of me I can't see how to do this - unless you build individual pieces and glue them end-to-end. I've done wheat, herringbone and step, but would like some examples or "how to's" on how to achieve the different mosaic looks.

Is there a toot out there? Is there a book on how to create the different mosaics?

Thanks in advance.
Steve

Hi Steve, you need to get beyond thinking of the rosette or purfling being made up of little square or rectangular "pixels" and think of patterns that can be created out of long shaped pieces the cross sections of which, once assembled, will yield the pattern that you want.
Jose Romanillos does this with his signature rosettes, the Roy Courtnall book "Making Master Guitars" actually gives a good description on how this is done.
Another 19th Century Spanish luthier who did amazing marquetry work is Vicente Arias.
Here is one of his rosettes:
As you can see, his patterns are made up of interlocking shapes.
Here is an Arias inspired rosette design that I've been working on. Long shaped sticks were milled using 1/4" cove and roundover router bits using the router tabe itself as a miniature shaper table and assembled using tubular inner and outer cauls for gluing up additional veneer layers.
The object is to form (hopefully) an interlocking ring pattern once assembled:

Here is the series of steps in making the log and pattern shown above:
First, East Indian rosewood stock was shaped on the edges with a 1/4" roundover bit

Then quarter rounds were sliced off the stock......

And glued together to form a 1/2" "half round"

Some of the quarter round rods were shaped using a 1/4" cove bit to form the concave triangular sections

The 1/2" half round was also shaped for a concave section along the center

Gluing the first of the WBW circle sections in .3mm veneer using pvc pipe sections as a gluing caul

The sections were made double length as they would be cut in half and joined together to form the final log

Trimming and truing up the overhang. The concave quarter round sections were glued.

Attaching the next section of WBW "Ring"

Making the end cap section

Assembling the final log from the two identical halves


I wish I had final shots of a finished rosette but alas I've been busy with commissions all year and shelved this one after getting the tiles cut (above post).
Hopefully though you get the idea of how to use interlocking shapes to form patterns which go beyond the usual rosette.

Very nice, David! That's quite an elaborate process to create those tiles. Thanks for posting, and be sure to show us the finished result whenever you get back to that one

As to the original post, what about building up the log out of small sticks like normal, and then using a long drill bit on a drill press to make a hole through it the long way, and then shove a dowel through it?

You could also brute-force it by drilling and inlaying dots one at a time in the finished rosette, but that would of course take longer and be less identical on each tile. It could also be interesting to do it like that, but without trying to make it repeat with the tiles... make a different pattern out of the dots on top of the mosaic. Or even do something like my rosette style, building a more elaborate non-repeating image, but with a mosaic background instead of solid wood. I think I'll have to try that sometime.

And here's a photo album that I ran across that has some great marquetry rosettes, including some in-process shots of one like that Arias rosette David posted. http://www.flickr.com/photos/rigoletto/
Looks like he does it using a wood strip bent into a squiggly line, semi-circles that match the bend radius on the squiggle, and putty or sawdust/glue mix to fill the rest of the space.

There is also a fellow who makes "Dowels on Demand" in any size and out of any woods.
These could certainly be incorporated into a log in order to create a simple circle pattern.

David, I'm intrigued by your pattern! Wonderful!

I'm just as intrigued with your small table saw and router/shaper as I am in the process. Could those be Proxon mini's?

I will definitely need to get Courtnall's book for ideas. I see such wonderful work. Its difficult for me to reverse engineer in my mind the process.

Steve,
The router is just a regular small Ryobi model clamped to the bench with an aftermarket baseplate and template guide ground flush with a plexi fence added. This essentially is a mini router /shaper table. The saw is the small table saw by Micro Mark.
I appreciate everyone's comments!

Thank you David for showing this elaborate process. This is really impressive!

I only got stuck understanding how you shaped the small center piece, the flat one which is squeezed between the interlaced rings. Is this flat piece made of two pieces, each glued to the "inner veneer" and planed or routed flat before assemling the two identical halves of the whole pattern?

I'm a bit affraid that I probably did not express myself clearly, so here's a picture:


I guess it's 2), but how did you achieve it? Same question if it would be 1) or a third option I did not think of...

Hi Markus,
When I realized that I would need a small strip to fill that space I just cut a thin strip and filed the edges.
As I remember your #1 diagram with the eliptical cross section is pretty close.

Best!

Thank you David!


Hi Steve,
When I first read your question I had to think of this awsome purfling of Torres' FE08:


Romanillos decribes the making process of the lozenge strip in his book Antonio de Torres, Guitar Maker - His Life and Work on page 165.

I made some drawings to explain it without copying the book (never made such a purfling though...)

Make a sandwich of black-white-black veneer and cut to strips, glue angeled strips together as shown:


The new glue-up must be cut in strips again.
Then, the "stair" is smoothed away, Romanillos does not mention how, I probably would do with a sharp chisel:


When the purfling is not that tiny as Torres', I think it makes sense to also try dots instead of an only- lozenge pattern:




But again, all this is only theory to me although one day I surely will give it a try.
I hope this served for getting inspired.

probably not a good police to revive old threads, but i couldn´t help. this deserves a bump!
I found this thread while searching for mosaic work, and couldn´t be more delighted...

thanks for the work, David!

cheers,
miguel

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member of the guild of professional dilettantes

If you want to see purfling, check out Al Carruth's site.

http://www.alcarruthluthier.com/guitars/autumnClassical/autumnClassical.htm

Very nice David;
Thanks for showing the method to make this .
As usual your dedication to quality & attention to detail
is an insperation to all !

Mc

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Mike Collins

Very nice David;
Thanks for showing the method to make this .
As usual your dedication to quality & attention to detail
is an insperation to all !

Mc

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Mike Collins

@Mike: that work is trully stunning. thanks for the heads-up!

_________________
member of the guild of professional dilettantes

What a coincidence! I was just thinking about this thread yesterday, and specifically doing something like the purfling on that Carruth guitar. Thanks for posting that, Mike, and Miguel for reviving the thread

The small pieces of wood in Al's mosaic are side grain instead of end grain. I've seen Al demonstrate the process and it is quite straight forward and each step should be easy. That is to make the pieces. Designing the logs and the dozens of custom planing jigs is the hard part. I don't think that I could reproduce it without a refresher course. If you want to do this kind of purfling, spending a week in Al's shop would be well worth the money.

i would do that very happily, if it wasn´t for the fact that i live in the other side of the pond and have two small babies to take care of. but when they grow a bit older, it would be something i would enjoy doing very much.

cheers,
Miguel.

_________________
member of the guild of professional dilettantes