I've been making my own bottleneck slides over a number of years - but just can't get a finish resembling your own finished products - how'd you do it? -
Danny Clayburn, Albuquerque NM.
We're privileged to be based in one of Europe's top specialist glass restoration & repair 'cold-work' workshops, allowing us access to both 'state of the art' and traditional hand-crafting glassworking (Lapidary) equipment.
Our fully water-fed equipment allows us to cut the neck from the bottle (or cut up our lead crystal tubes & bars) to any required length, shape the necessary cut profiles and final-finish the piece using a three-stage sanding belt polishing cycle to create a totally flawless, mirror finish high lustre product. Our craftsmen then hand-shape & polish the inner chamfers using diamond files & two ultra-fine cerium oxide pastes to dispose of any sharpness or internal chipping that will affect the playing comfort of the finished slide ~ please check out our 'Workshop Spotlight' page to see this in action!
I've read that different glass colors affect guitar tones - is this true?
Paul Oakey, United Kingdom.
It certainly is! The main tonal difference is between the 'base' colors of clear soda lime bottle glass; green soda lime bottle glass; and cobalt blue soda lime bottle glass (these are the three most common glass colors used for authentic bottlenecks) - this will be most noticeable on acoustic/resonator instruments.
Clear, uncolored bottle glass will give a warm, smooth tone - albeit with slightly less volume than the other available color choices...good for electric slide guitar!
Green bottle glass is colored using iron-oxides, giving an excellent 'all-round' tone with more of a tonal 'bite' and warmer sustain than clear bottle glass, and with a noticeably slight rise in volume levels due to the harder 'properties' found in green glass.
Cobalt blue bottle glass is the hardest of all commercially available bottle glass, using cobalt oxide to provide the blue hue. Cobalt blue bottle glass will give the loudest volume of the three 'base' colors - the tone being best described as bright & 'spiky'!
The subtle shading differences of each soda lime bottle glass color can alter your tone very slightly - but not so noticeably as between the three different 'base' colors listed above, and occasionally brown. Brown bottle glass is more commonly used in beer bottling over here in Europe, and beer bottles have quite thin walls which are fine for 'high-octane' electric slide duties - but not so hot on acoustic/resonator instruments.
So what are the differences between all the glass types commonly used in guitar slides?
George Birkmaier, Germany.
There are three main types of glass used for guitar slides: soda-lime (commercial bottle glass), boro-silicate (commonly known in the glass trade as Pyrex), and hand-blown, furnace-fired lead crystal.
The cheapest of the three glass products is soda-lime - a tough glass used mostly in commercial bottling. These make excellent 'all-round' glass guitar slides offering the player a slide with nice weight, good sustain and a sweet tone. They're easy to make yourself after some practice and can also be obtained from specialist, internet-based slide-makers and listed music stores.
Boro-silicate (Pyrex) is a low-expansion, higher temperature melting glass which is annealed to allow the glass to harden. These boro-silicate (Pyrex) glass slides are cheaper & more easily obtainable (most music stores carry a good selection) than genuine bottlenecks, and can be bought in many differing internal diameters, slide lengths & wall thicknesses.
The downside to boro-silicate (Pyrex) slides is in the glass structure - the glass is lighter in weight than authentic soda-lime bottleneck slides and therefore sustain, warm tone and volume are limited - again, this will be especially noticeable on most acoustic & resonator instruments.
Lead Crystal is quite simply the finest glass product currently manufactured today for guitar slides. Slightly softer in structure than commercial soda-lime bottle glass but slow-annealed in custom-built Lehr's to provide the durability of the harder soda-lime glass, the addition of lead oxides (colored pigments) into the basic glass 'mix' allows for the beautiful colorings and a pure tonal clarity, with a resonance totally unmatched by any other glass slide product available.
These lead oxides added to the glass 'mix' (our U.K. glassblowers use a common 24% lead/silicate split) allow the player to use a thinner wall-thickness crystal slide, giving a superior tonal advantage and sustain over & above any available thicker-walled soda-lime & Pyrex glass slide....perfect for electric slide/lead players to fly around the fingerboard!
As you move up to a heavier, thicker-walled lead crystal glass slide, the overtones become noticeably more fuller and more resonant, with sweet, smooth sustain and a warm 'liquid' tone...perfect for wood-bodied acoustic & resonator instruments.
A big plus here is the fact that at a legally-designated lead/silicate 'mix' of 24%, the question of any form of health hazard to the user is negligable...a 100% totally safe glass product, unless your desire is to eat around 50 of 'em for dinner!
Your dealer/stockist list is quite limited - why is this?
Brian Ross; London, England.
It's simply because around 90 - 95% of our workshop output is focused toward the demands of our individual custom-order market ~ the creation of the custom-order glass slides we here at Diamond Bottlenecks' are best known for is far easier to control (and a lot more fun!) than trying to supply a large number of music stores with sliding glassware on a regular basis.
We do list a small number of select guitar stores around the world which we're very proud and honored to stock our slide range - but it's more adventageous for us here to supply guitar stores which feature the slide guitar & slide-related products prominently in their inventory.
Other slide-makers offer tuning guides and other various temptations to buy their products....why not you folks?
Imtiaz Kazi, Eastern Europe.
Our sliding glassware receives the 100% total concentration & commitment it requires - if it takes our craftsmen hours to create one perfect custom-order glass guitar slide, that's fine for us! We have no need, desire, or received requests from our customers to offer anything other than the best glass guitar slides in the world!!!
Are many bottles rejected in the manufacturing process?
Fabien Tissander; Paris, France.
Very few, if any at all. There is much conjecture about the amount of surface smoothness bottle glass requires to provide optimum slide tone. The smoothest glass isn't necessarily the best glass tonally for a guitar slide - we recommend glass quality over surface smoothness.
For three decades now we've created authentic glass bottleneck slides from many hundreds of different re-cycled bottle types, styles & a variety of glass colors available to us from around the world - the majority of these have unfortunately provided us with quite uninspiring results, both in tone and volume.
Therefore, through our long experience and over many years of testing, we've graded our results and now only use around twenty or so currently available types of re-cycled bottle that have the premium-grade glass quality we consider necessary to create our 'Original' & 'Redhouse' bottleneck slide range - and we're very proud to say we've never had one negative comment about the bottles we use! If we do find a particular premium quality bottle that is perfect for a bottleneck, but has an inconsistency or flaw in the playing surface, our de-seaming / final-polishing equipment will blend the flaw invisibly into the playing surface.
...hopefully these genuine F.A.Q.'s will be of benefit to all guitarists currently easing their way into the wonderful world of slide guitar. The science of guitar slides is continually evolving, with a plethora of new slidemakers/designers regularly bringing their wares into the marketplace utilizing on-line websites offering a vast array of different materials, suggestions & opinions that can only further the growing interest in slide guitar - never has the fledgling slide-player had so much information at their fingertips to assist in the learning of their craft!
Many thanks for your time & continued interest;