Block design banjo rims have been around for a long time. Famous high quality brands including the Imperial, Stelling and Wildwood names have sported block rims through out their history. Since the Stelling brand switched to traditional three ply rims almost two decades ago, Wildwood has carried the torch as the lone professional brand to build with this non traditional design.

The world of banjo builders and players is being awakened once again to the high performance sound of the block rim banjo. I want to give an overview of the block banjo rim and the new advances available to banjo players.

Basic Construction

The traditional three ply rim is constructed of three layers of quarter inch thick flat sawn maple that are steamed, bent and glued together around a form in such a way to build up a rim structure three quarters
inch thick and the proper diameter to fit the tone ring and flange. The grain structure in this case allows for the grain to be oriented vertically. In other words the sound waves pass through the tone ring and go into the wood rim and travel straight along the wood grain into the resonator.

The block rim is constructed of multiple layers (usually three) of blocks of wood. The blocks are usually cut with angled ends so that you can glue six or eight together and form a pie cut circle. You glue up
three sets of these pie cut rings, then glue these rings together in a stack. The grain can be oriented either flat or vertical. Using quarter sawn vertical grain wood follows traditional musical instrument and
sound theory, although I have seen no concrete evidence that either is superior in this case. At this point you have a similar structure to an uncut three ply rim. Both rims are cut to shape on a lathe in the same
manner to fit the tone ring and flange.

Block rims can be constructed without the need for complicated bending jigs and sometimes dangerous bending situations involving boiling water or steam. For this reason some new banjo builders choose the block rim construction because it seems easier. In truth a professional quality block rim requires much more care and a high degree of craftsmanship to build. Many people think of block rims and remember pictures in books and magazines of rims with huge glue filled gaps and joints that lend themselves to structural weakness. A professional block rim has no gaps in assembly and glue joints with tolerances worthy of a metalworker.

What you can expect from a professional maple block rim is a banjo with exceptional power, sometimes dramatically different, compared to a banjo built from the same parts in a traditional three play rim. You will
notice a slight increase in brightness coupled with unsurpassed clarity in all tonal ranges. Because of their power, clarity and tonal range, they offer a new standard of dynamics not available on your typical three ply wood rim. And just like the traditional construction, set up is all important. A block rim is not for the timid banjo player, you will stand out.

I have heard discussions among people about what kind of banjo will work with one of these rims. I hear a lot of misinformation, too often from those who don't know the current level of technology and
craftsmanship being practiced. In truth, ANY banjo can be converted to a block rim if you approach the right person. I have seen on the internet discussions, people boldly advising that a block rim will not be
appropriate for Mastertone style banjo. This is ignorance. A quality block rim will enhance everything that is good in a bluegrass banjo, often surpassing the qualities that define bluegrass banjo.

Bluegrass Banjo Block Rims 2002

The current Master of the block rim and the man single handedly responsible for its renaissance is Tony Pass of Louann, Arkansas. Tony is a retired machine designer of thirty years as well as a Master gunsmith and crafter of competition grade rifles. This makes him a rare person indeed. He is an engineer with the hands of a Master Craftsman. Tony works in thousandths of an inch, a carry over from his designing and gunsmithing days. Every block in a wood rim is measured with calipers to .001", and it shows both visually in his rims and most importantly you can hear the difference. Tony talks about the evolution of his rim construction, which started out better than anything ever built before, and has progressed to the point where he says his early rims and the current rims have noticeable sound differences that he can hear. His current rims visually don't look any different than the original ones, but Tony has a number of proprietary exclusive techniques hidden within his rims that insure that no one is likely to surpass his rims for strength, looks or performance. One of the few trade secrets Tony willingly gives away is that under no circumstances should a block wood rim be constructed with dowels to hold it together. This will,
every time, result in inferior performance. And to those who say its necessary for strength, he jokingly scoffs, and recommends they elevate their technique in gluing beyond junior high school shop class. Tony
proudly proclaims that his rims are "virtually" glueless. By this he means that his joints are so perfect that by the time the glue is squeezed out of the joints when clamped, it is virtually a wood to wood contact. Coupled with the interesting fact that Tony has calculated that the TOTAL square inch surface area of glued contact in one of his block rims is equal to less then one ply of a three ply rim. Needless to say, less glue means improved acoustic performance. This is achieved without any sacrifice in strength.

Indeed, I have done tests on these rims where I left one pulled into an extreme egg shape for months with coordinator rods and when released it returned to round with NO glue joint problems at all. I have one rim that is now one and one half years old that is sitting unmounted and unpainted. It has undergone minus ten degrees with the kerosene stove pulling the humidity down to ten percent in the winter and gone to over one hundred degrees with the humidity close to one hundred in the summer. This rim is still in perfect condition. When asked why he thinks block rims were not popular as far back as the thirties, Tony feels that, for one, the block rim is labor intensive compared to the three ply rim. And another point is that he feels modern adhesives are critical to the block rim both for strength and sound. The hide glue of ages gone by is well known as problematic and while strong, is very prone to failure when heat and moisture levels reach key limits. Limits most banjo players expose their banjo to.

Tony's research has included testing numerous glues for strength and acoustic properties, glue joints, wood varieties, tone rings, and even finish. His rims have evolved over the past year and a half by doing honest testing and seeking out key people and experts to consult with. This is how Tony and I met, and I am honored to be a small part of this exciting project. He insists that it is not only the block design but exactly how the construction is done that effect the outcome. Tony has kept sound files recorded under identical situations and can chronicle each and every change and its effect on sound.

My work with Tony focused on the use of the now legendary sunken old growth woods. I have been using this wood for a few years now and pioneered its use in a number of musical instrument applications. When
Tony started making his block rims out of sunken maple, the banjo world was given a big boost. The use of this timber was just beginning in traditional three ply wood rims with great success, but the results with
the block design were in my opinion more dramatic. I did a conversion on an old Ode banjo as my first test. The instrument was turned into an extremely powerful well balanced cannon of a banjo. Following this I built numerous new banjos with many of the current popular tone rings. ALL outperformed the same instrument configuration with a traditional three play rim.

In 2001 at my invitation, Tony joined me in my booth at IBMA. Tony brought his personal banjo, a Stelling that he had converted with a submerged maple block rim. Before the end of the first day of the Trade
Show, the word had reached Geoff Stelling about this banjo and he came to our booth and asked to try it. As they say, the rest is history. Geoff immediately realized the potential. A Stelling with an old wood rim by Tony Pass has been described as what a prewar Stelling must sound like if there was such a thing. The banjos are even more powerful than their stock cousins, with a bottom end to their tonal range the likes
of which have never been seen in a Stelling before.

Geoff says the effect of the Tony Pass rim on his banjos is "Nothing less than INCREDIBLE!!" Geoff was the first one to suggest the use of birch instead of maple. Geoff used birch block rims in the early years, and has always liked the sound of birch. Geoff says, "I would never have switched to three ply maple rims had not my machinist gone out of business"... The supply of the sunken woods is something that must be
managed in a production situation and maple is always in short supply. So the promise of using birch offered some interesting chances. None of us were prepared for the results. In the Stelling banjos the birch
opened the "window" on a mid and bass range of tones that are redefining the Stelling sound. And in traditional Mastertone style banjos, the block rims made from Lost Forest sunken birch are now being recognized as being a possible missing link in the evolution of the mysterious and elusive "Prewar" tone. Again, its the mid and bass tones with depth and power that are turning heads, while at the same time keeping a clarity in all positions of the fret board that a three ply rim rarely achieves. This is a tall claim indeed, but these characteristics are noted in the feedback offered from the people playing the banjos, not by those of us doing the research. This year at IBMA 2002 an impressive number of good banjo players including a number of professionals played the banjos in our booth, and comments were consistent that when coupled with a quality tone ring like the JLS, or Tennessee 20 or the new tone ring by Paul Hopkins, these banjos performed at a level second to none. In addition there were recognized banjo players at the event like Kipper Stitt of Pine Mountain Railroad with his 1970's Mastertone with all original tone ring and flange and a Tony Pass birch rim and set up by banjo set up guru Kyle Smith. This banjo had more power, and more strength of tone in all ranges than any banjo that was compared against it, including two of the most popular boutique "prewar" new banjos available today.

Tony no longer builds rims out of new wood. He sees no point as long as the supply of the recovered old growth wood remains consistent. The results are too dramatic. He builds about ninety percent of his rims out of birch and the remainder in maple.

At this years IBMA, Tony was approached by a number of prominent banjo makers. Tony will be offering his custom block rims to a select maker or two of Mastertone style instruments, and is making samples for these brands now. Building rims for Stelling and a growing number of banjo owners who want to upgrade their banjo allows him only enough time to carefully select a new customer or two to build for.

Tony will always build for individuals, and can fit a block rim to virtually any banjo whether bluegrass or open back.

Scott Zimmerman
www.desertrosebanjo.com