Zipflex interview with Kevin Ryan.

Zipflex. Kevin Ryan.  | 2009

Zipflex inlay material

Kevin Ryan is a world reknown luthier and also innovator. Recently, I have been hearing about an easy to install shell purfling from Kevin’s Advanced Shell Technology company called Zipflex. Several luthiers have praised it’s ease of application and beauty. I managed to catch up with Kevin to find out more about this new product.

TT – Thanks for taking the time to speak to us, Kevin.  Perhaps you could start off by giving us some background into how you developed ZipFlex?

Zipflex inlay material

KR – I remember the moment it all started. I had reluctantly agreed to inlay abalone around the sides and back of a guitar for a good friend and client. I say reluctantly because the procedure for that is fairly labor intensive. And it was on a Florentine cutaway to boot. So there I am slammed like usual in the schedule trying to keep up with my commitments and now I have another minor hiccup in the building schedule.

So in desperation, I tried to think of a way to make that inlay job better and faster. And I had this quick idea to attach some straight abalone strips to a piece of tape and then break the strip into little pieces that could hold together while I inlaid it into the inside radius of the cutaway.

Well, it worked, sort of. And then, being the tinkerer I am, I thought of a little improvement and then I did that. Still not quite what I wanted. Then I had another idea that made a little more headway. That was the next day.

Zipflex inlay material

And then the light started going on in my head. I realized that if I could figure this out, really and truly figure out how to make this system work, it would revolutionize how I did all my edging inlays here in my shop.

So about a week later I was fully obsessed with figuring it out. And I have to say that it went through about 4 or 5 iterations in the first few months. Each advancement was exciting but with each step forward there were other unintended consequences. And then I went through a stage where I was actually trying to attach the BWB purfling to it as well.

That was pretty encouraging until I realized that there were so many kinds of purflings, sizes and looks, that if I ever intended to sell the stuff (originally called FlexiAb) then attaching the purflings really complicated things. For instance, one particular large manufacturer who was committed to making the FlexiAb work in their factory began asking me about using their 3 different styles of purfling. And then there was the several different kinds of shell I could use with each style of purfling… in short order I realized that this was a recipe for insanity for me. That all happened about a year after the original idea.

And between that original flash of inspiration and the discouragement of being overwhelmed with all the details that I would have to track, there was the entire, actual R&D in figuring out how to perform each step and the materials involved. And here I have to say that the technical reps from 3M were incredible to work with. At one point it seemed there was an entire small team from 3M working with me and the secondary materials (the Abalam of the Duke of Pearl was a given in the formula). And that work with 3M took another 4-5 months of intense prototyping and the making of sample after sample.

There were a number of times in this long period where I was just about out of steam with it. Every little success created other issues that had to be dealt with. A material I could mill could not be glued; a material I could glue could not be milled; a material that was very good was yellow (a deal breaker); another material that was almost ideal was not available in the correct dimensions; and on and on. But at that point I was in too deep to turn back.

And besides, there was that moment along the way with a new version when for the first time it really could bend easily against its long axis, thus making it ideal for the inlay on the soundboard and not just the sides. At that instant, I realized that this stuff was going to be a big deal. And my dear friend (like a brother to me) Chuck Erickson (The Duke of Pearl himself!) was so encouraging to me. He said without hesitation that the ZipFlex would transform the inlay world much like Abalam had transformed it a decade earlier.

So now I had a full head of steam again and was putting the finishing touches on the very complicated manufacturing process (I use my CNC mill, I use my laser, I use all the conventional tools as well). The final breakthrough occurred after a meeting with yet another very large guitar company (who will remain unidentified due to confidentiality agreements) when we developed the tooling and philosophy to make each segment of ZipFlex 15” long. The conventional Abalam strips then commercially available were only about 5” long. The ZipFlex was now 3 times that length which made it all the more easily installed and attractive to factories and solo builders alike.

At the end of the day, there were 3 years of research and development to get ZipFlex to its present form. And I have boxes and boxes of every conceivable matrix, glue, binder, substrate, endmill and adhesive you can imagine. But it was all worth that moment when I pulled our first perfected ZipFlex segment off the Rube Goldberg-like assembly fixture!

TT – I understand that ZipFlex can be made of any Abalam material?

KR – yes, that was one of the cool things about using Chuck Erickson’s Abalam—if they could make it into Abalam, we could make it into ZipFlex. The palette of colors and grains and looks was extensive.

TT – The matrix on the perimeter of ZipFlex- is there anyway to eliminate that from the final inlay?

KR – It could be done. In fact one guy does that very thing. But when the dust settles, I cannot imagine the scenario where I would want to do that. In fact, one of the challenges was to create the ZipFlex with a small, built-in black purfling line. I myself will never allow shell to be against any line or purfling other than black. It can have BWB purfling but the shell has to hit the black first.

So for me I love the black line there. Especially when inlaying the sides and the back. There I do not use the more conventional BWB purflings. I use them on the soundboard to create a bolder look, but on the back and sides I want a more understated look. So there I use only the ZipFlex. So the narrow .005” black line frames the shell against the wood and binding and creates that crisp look that I love.

TT – Maybe I could trouble you for a brief explaination for our readers on how the inlaying process is simplified with Zipflex vs. traditional methods?

KR – The typical method to inlay shell around the edges of a guitar is to glue in a strip of Teflon or polypropylene along with the purflings and bindings. Then when the glue sets up, the tape or binding is removed and the plastic strip is removed (usually destroying the Teflon strip. Then strips of shell or Abalam are carefully and tediously broken into that channel. With the ZipFlex, there is no need for the one-use Teflon strip. The builder just tapes in the ZipFlex instead of the Teflon. That’s it. It’s done.

TT – And you mention on the website that all abalam-able types work but the lighter shells show up cracks more- is this also the case for wider strips?

KR – Yes, that is also the case for the wider strips, but only when they are navigating a tight waist or cutaway. On a guitar like a dreadnaught or a non-cutaway, I don’t think it makes a difference.

Zipflex inlay material

TT – I was just thinking that the straight abalone strips would be ideal for the length of say a fingerboard but maybe zipflex for a fancy fingerboard termination- would there be any trouble with the mitre between the two – straight abalam and zipflex?

KR – I don’t think that mitering the ZipFlex is the best use of it. Mitering the ZipFlex with the matrix attached can be tedious. What I do here in my shop is to simply peel back the matrix and butt-joint the shell. This works very well and is just not noticeable on the finished guitar. Another possibility I am exploring for a very large guitar factory is to have some standard straight strips that can integrate into the ZipFlex. But at the end of the day, I like the simplicity of the method I use here in my shop.

TT – Thanks Kevin! I understand that you have more innovative products in the pipeline too?

Zipflex inlay material

KR – Yep, I am finalizing my A4 kerfing liner and clamps; I have designed some titanium bridge pins that are available and will be on my Advanced Shell Technology website soon.

I will be offering some of my EO bracing, a special headblock system and also possibly my new Acoustic Parallel Plate which is a hybrid double top bracing component.

At some point I will also offer some of my inlays, loose or in fretboards and also a cool new inlay product I call Universal MicroPearl. The UMP is a radiused Abalam arc that is flexible enough to accommodate all the different radii of a standard rosette. It is a pretty cool product that really makes creating a stunning rosette detail very easy.

I will be offering regular straight strips Abalam. There are number of places where a builder does not need the ZipFlex, say, the backstrip or the edge of the fretboard. For these places, I will be offering the standard strips.

And I am also considering offering my micro-adjustable, truss rod/stiffening system. It is the magic behind my neck playability and relief. There is nothing like it in the world and it could immediately solve some of the common issues that plague guitarbuilders. I jokingly tell other builders that if I could not use my own truss rod, I would quit building guitars.

And finally, I have some ideas that are keeping me awake at night that I cannot tell you about yet! How is that for a tease?

TT – Ouch we’ll just to wait & see I guess. In the meanwhile, do let us know when A4 kerfing and UMP is ready for the market and we’ll get a low down from you!!

©2009 Terence Tan.
Pictures courtesy of Kevin Ryan
Check out Kevin’s Advanced Shell Technology website: link

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