BILL COMINS - 16" "Zelig" Hybrid Carved Top: Carpathian Spruce/Honduran Mahogany

[Marcus Wong]

Originally Posted by iim7V7IM7

Marcus, the credit goes 100% to Bill. The rosette was his idea and execution. I merely said "OK". Bill has a wonderful aesthetic sensibility in his body work... check out some of his custom guitars (http://www.cominsguitars.com/comins-...tom-archtop%20).

It is indeed a nice set of fiddleback mahogany. Bill normally constructs using a multi-piece neck; but because the mahogany neck blank (also curly) is so figured, he is going to make a 1-piece neck. We haven't yet made a finish decision yet, but we will likely choose something that will enhance the figure.

Yup, I've seen his work. Very unique indeed! And going with a one piece neck with figure sounds like a great choice. Hope you're having a great holiday season

And very interesting fact about the customisable Rodger tuners. Probably would go with something of his down the line with a custom engraving

[iim7V7IM7]

Originally Posted by Marcus Wong

Yup, I've seen his work. Very unique indeed! And going with a one piece neck with figure sounds like a great choice. Hope you're having a great holiday season

And very interesting fact about the customisable Rodger tuners. Probably would go with something of his down the line with a custom engraving

Yes, I was surprised by the lack of an up-charge as well. I believe a neutral CAD transfer file format like a DXF file for the engraving is what Rob needs. Also, some recognition in the design provided of the constraints of an engraver. Rob's lead time is approximately 12-weeks so some forward planning is required as well.

[iim7V7IM7]

Bill has been working away on my guitar this week and forging ahead with the bracing scheme; the evolution of which has been slow going and very much rooted in both tradition and luthier's intuition. There is the added task of meticulously mating each Sitka Spruce brace to the complex curvature of the arched Carpathian Spruce plate.



While Bill's original idea was that he might need to reinforce the bracing with a fair amount of carbon fiber, but as he began to get a feel for the top and reconciling stiffness vs. the anticipated reduced downward pressure in comparison to traditional archtops, he thought it too soon to go overboard in terms of stiffening the top. He may still decide to cap the scalloped legs of the x-brace under the bridge area with a thin film of carbon fiber but thought it best to wait to check for stiffness/load distribution once the top has been secured to the rims . The braces can still altered and/or capped with carbon fiber at that point if need be. Bill also decided to hold off at this point in installing any finger braces until this point. Remember, although the plates are both somewhat thinner and flatter than a traditional archtop guitar, there is still a good bit of stiffness and structure inherent to the arching when compared to a flat soundboard. Here's a shot of the x-brace and tone bars as it stands now (upper shot).

He also included an image of the top (lower image) that displays the raised lower bout perimeter which allows for subtle curvature in the bridge/lower bout area while retaining the bolder contours and graduation of a traditional archtop in the upper bout. This geometry ensures an inevitable reduced downward pressure on the floating bridge from the tailpiece end, hence the thinning of the top and not wanting to overdo the bracing.



Here are two views that show the shaping of the arch at the bass and treble sides of the bridge area. You should be able to recognize more curvature on the treble side and mostly flatness on the bass side. He conveyed to me that he been thinking a lot this week as he progresses forward about the later guitars of Jimmy D'Aquisto; where a flattening/softening of his arched tops imparted a smoother/broader tonality to the archtop guitar.

[Archtop Guy]

Originally Posted by iim7V7IM7

Bill has been working away on my guitar this week and forging ahead with the bracing scheme; the evolution of which has been slow going and very much rooted in both tradition and luthier's intuition.

Wow, that's much more of an archtop / flatop hybrid than I'm used to seeing. From a labor / effort point of view, it's like the worst of both worlds! All the effort of carving plus the bracing. You and Comins really are adventurous. This is such a cool project, I am so anxious to follow it and hear the final product.

Thanks!

[iim7V7IM7]

Originally Posted by Archtop Guy

Wow, that's much more of an archtop / flatop hybrid than I'm used to seeing. From a labor / effort point of view, it's like the worst of both worlds! All the effort of carving plus the bracing. You and Comins really are adventurous. This is such a cool project, I am so anxious to follow it and hear the final product.

Thanks!

You're welcome... While it is indeed adventurous, I know that Bill is is very much enjoying the opportunity for exploration.

I know that he has been feeling a bit like we're somehow picking up with this project where Jimmy "D" left off. As the construction of this guitar like this is somewhat of an "uncharted course" the project is reliant the mastery of the luthier in applying their decades of amassed skill at listening, flexing, tapping, and intuition to navigate a course and synthesize something new. About a year ago, I explored similarly uncharted waters with luthier Bruce Sexauer (arched back/flat top) which I am delighted with the outcome (and so was he and others who auditioned it at Woodstock last year).

I also forgot to post one other shot that he sent me of the oval sound hole. Bill added a simple radiused Cocobolo binding to finish it of and visually tie together with the MOP triangle cast shadow in the rosette.

[strings4him]

Looks like a wonderful journey. You have a great collection of guitars (acoustic, electric and classical). Thanks for taking the time to share.

[fazool]

Originally Posted by iim7V7IM7

...
Bill designed these custom engravings for the brass plates of Rodgers tuners. Rob Rodgers shop did a very nice job implementing the designs. These engraving designs will tie into some other decoration features in the guitar that are planned.

These are gorgeous and now I have tuner GAS!

[iim7V7IM7]

Originally Posted by fazool

These are gorgeous and now I have tuner GAS!

I understand...

The mechanical quality of the Rodgers tuners is well beyond what is required for a guitar tuner to function extremely well. What really differentiates them, and why they are costly are the quality of the materials and level of finish work used in their plates and buttons; which is the without a doubt the best that I have seen. They are truly works of functional art and are customizable in plate style, plate material, plate edge finish, roller style/material and of course engraving to compliment a custom guitar design. I also have found communication with Rodgers to be excellent and their delivery timing to be 100% reliable.

But, to be objective and manage people's expectations, I don’t think the gearing precision of the Rogers 15:1 single gear units, while excellent; is perhaps the smallest step below the precision achieved in the best high quality factory tuners such as Gotoh 510 sealed 18:1/21:1 or Waverly 16:1 open-backed tuners. There is the tiniest bit of backlash between the gears and wobble in the button shafts that can be perceived when they're not under load. Of course, NONE of these minor artifacts of manufacturing imprecision are noticeable at all once the string tension is applied. I find the 15:1 ratio more than adequate for small tuning adjustments and they hold position beautifully.

[iim7V7IM7]

Bill provided another update today on the build. He has completed the rough contouring and Sitka Spruce bracing of the asymmetric Carpathian Spruce top plate. As you can see since the last update, the braces have been further refined and a thin layer of carbon fiber has been added to reinforce the bridge load bearing area of the x-brace. He has also added some finger braces in the recurve area of the lower bout. This was all done based upon how the top tapped, deflected and sounded under a stringed load. The top has been attached the bent Honduran Mahogany rims, neck and end blocks; Spanish Cedar linings and Sitka Spruce bracing installed to reinforce them.



More when I get it…

[jt1]

Bob,

Thanks for updating the thread! Gorgeous and fascinating stuff.

[iim7V7IM7]

Originally Posted by jt1

Bob,

Thanks for updating the thread! Gorgeous and fascinating stuff.

You're welcome JT...Definitely a marriage of Kalamazoo and Nazareth going on in this hybrid approach. We're headed on the map for the edge of the Earth where dragons lie...

[iim7V7IM7]

Bill reinforced a 15' dished, Honduran Mahogany back with a reinforcement strip and four shaped Sitka Spruce ladder braces (right). The refined contours and scraped recurve of the carved Carpathian Spruce top can be seen here as well (left).



Now that the 16" "box" has been closed, the graceful proportions of the body and the real hybrid nature of the design can be seen. Unlike a traditional archtop with a constant depth rims of 2-3/4" to 3-3/8", the flat back is tapered from about 3" at the neck block to 4-1/8" at the end block. This is more akin to a Gypsy guitar. You can also see in the side view how shallow the arch is and how the carved top falls off as it accommodates the neck extension. We decided to go without a back strip to emphasize the beautiful fiddleback figure of this set of Honduran Mahogany.



More when I get it....

[Steve Kinnaird]

Originally Posted by iim7V7IM7

I also forgot to post one other shot that he sent me of the oval sound hole. Bill added a simple radiused Cocobolo binding to finish it of and visually tie together with the MOP triangle cast shadow in the rosette.

That Cocobolo line, though subtle, just makes the rosette for me.
Very nice!

Steve

[iim7V7IM7]

Originally Posted by Steve Kinnaird

That Cocobolo line, though subtle, just makes the rosette for me.
Very nice!

Steve

Thanks Steve...

We'll bind the body with cocobolo as well. In general, a simple, clean aesthetic is on order for this project. Being an archtop, we can however have some gestural fun with the form of the fingerest, bridge and tailpiece.

The key thing up to now has been figuring out the top, its bracing and the proper negative neck and tailpiece angle to create the correct downward pressure to make the the top "sing".

[iim7V7IM7]

We made some decisions regarding the neck of the guitar. We are going with a 25-1/4" scale length and a 1-3/4" nut width on this guitar. Bill cut the beautiful curly Honduran Mahogany neck blank. The fiddleback is slighly on the bias to the length of the blank. We may still go with a one-piece neck or alternatively with a bookmatched, multi-piece neck (tbd). We also agreed on a peghead shape and a finger rest design.