All of our leather goes through on of these tanning methods:
Chrome Tanned – this process uses soluble chromium salts, primarily chromium sulfate, to tan the leather. Batches are test to assure minimum 4.5 0/0 chromium salts.
Chrome Oil Tanned – This leather is primarily chrome tanned and then treated with an oil that helps preserve the leather.
Alum Tanned – Colorless aluminum salts are used to tan this leather.
Vegetable Tanned – Vegetable materials derived from tree bark and various other materials are used during this tanning process.
Veg Chrome Tanned – This leather is vegetable tanned (as described above) and then re-tanned in chromium salts.
Glace’ Tanned – A tanning procedure based on the exclusive use of a mixture of: alum, salt, egg yolks, fat, and water. This method had been developed and tested over decades.
Explaining the Incredible Tensile Strength of Kangaroo Leather
Kangaroo Leather is widely accepted as being one of the strongest lightweight leathers available. However, the reasons for this incredible strength are not widely appreciated.
When split into thinner substances, kangaroo retains considerably more of the original tensile strength than does calf. When split to 20% of the original thickness kangaroo retains between 30 - 60% of the tensile strength of the unsplit hide. Calf retains only 1 - 4% of the original strength.
Kangaroo has been shown to have a highly uniform orientation of fiber bundles in parallel with the skin surface. It does not contain sweat glands or erector pili. Muscle and elastin is evenly distributed throughout the skin thickness. This structural uniformity explains both the greater tensile strength of the whole leather and the greater retention of strength in splits.
Taken from an article in Newr Journal of the Australian Kangaroo Industry.
Kangaroos are the most often seen and well known of Australia’s wild animals. Some widespread and abundant types of kangaroos are harvested commercially. This helps solve the problems that large umbers of kangaroos can cause farmers and grazers. In this way, best commercial use is made of a natural resource.
Why Harvest Kangaroos?
Certain species of kangaroo are so common in some areas that they cause major damage to farming properties. In large numbers they can ruin crops and damage fences. They also compete with livestock for food and water. Landholders can lose income as a result. Commercial harvesting lessens the risk at no cost to the landowner. Increasingly kangaroos are being seen as a valuable natural resource for their meat and skins – rather than a possible rural problem. Harvesting kangaroos can change a problem into an important and valuable part of a farm’s income and management.
How Kangaroos are Harvested
Kangaroo harvests are carried out by licensed shooters. With the landlord’s consent, the shooters work on these properties where authorities consider kangaroos are causing damage. The carcasses of harvested animals are sold to a processor, who then sells the meat and the skins to markets in Australia and overseas. Most of the skins are sent to tanneries and leatherworkers. Commercial harvesting does not occur in national parks or conservation reserves and quotas are set to limit the number of kangaroos that can be harvested each year.
The future of Kangaroo Management
Australia’s Federal, State, and Territorial Governments are committed to protecting and conserving all kangaroo species over their natural range. Current harvesting practices have many advantages over other kangaroo control measures. Acceptance of kangaroos as a valuable natural resource to be managed, rather than as a pest to be eliminated, leads to landowners managing their land to carry more kangaroos on their property.
History of Leather Tanning and It's Movement Into the New Millennium
Tanning traces its roots in the New World in the early 1600’s in the Northeast. This area contained the necessary elements of good leather crafting: soft water, fur bearing animals, and tanning materials from tree bark. A few tanneries remain dating back over a hundred years. The Leather Supply House in proud of working with these US tanneries located in Massachusetts, New York, Wisconsin, and California. They began and remain a family owned business. This sense of closeness in enhanced further by numerous family connections among current employees. The craft parallels that of organ building, both being rich in traditions.
Throughout the early part of the 1900’s the leather industry was a very important part og the US economy and social culture. Between 80-90% of the leather was tanned in the US. During both World Wars and the Depression, the tanneries prospered due to the constant demand for military and domestic leather products. They remained stable until the late 1970’s when 3 international events took place: Russia was at war with Afghanistan, the Ayatollah took over Iran (hence an embargo on African hairsheep), and Turkey chose not to export raw sheepskins. These countries supplied the fine raw material used to produce lightweight organ leather. Further, the efforts of the Environmental Protection Act caused many tanneries to close rather than invest in compliance measures.
Today, in an era of manufacturing companies moving offshore for economic reasons, the tanneries purchase our leather from are determined to remain in business. By investing in ownership in raw material plants in Africa and Haiti, they can produce high quality leather to the specifications recommended in Aging of Organ Leather* by completing the finishing process stateside. Traditions and a new level of college-trained employees enable quality control in management and production to achieve the highest quality leather. Using the best materials, upgraded and new machinery, improvements in buildings and work conditions, demonstrated to the community, their employees and us the dedication to maximum performance in producing quality leather.
The Leather Supply house, these global tanneries, along with the Leather Industries of America are working diligently to continue the use of chromic oxide in the tanning process and the latest techniques insure that our tanners and the Leather Supply House will remain viable well into the 21st Century and beyond.
* Aging of Organ Leather – Harley Piltingsrud, Principal Investigator Jean Tancous, Co-Author 1994 Copyright – The Organ Historical Society, Richmond, VA.
How to Measure Leather Weights and Thicknesses
Every ounce is equal to 1/64’ in thickness. Leather always has slight variations in thickness. As a result, leather hides will seldom measure exact throughout. Hides run through a splitting/buffing machine have greater (but not perfect) uniformity. “A” grade is the tannery’s highest grade of leather available. We only purchase and sell grade “A” leather. Grade “A” allows for 1-2 small defects in the prime area and 2-3 defects in the non-prime area.
Note: “Weights are gauged in the butt area, along the backbone and approximately six inches in” Tanners Council of America, Inc.
Leather is accurately measured by machine at the tannery, and the square footage is marked on each hide.
To keep updated about the changing world of leather tanneries and processes, we depend upon the following sources:
Leather Industries Research Laboratory – University of Cincinnati
Leather Industries of America (LIA), one of the oldest trade associations in the US that interests the American leather industry
BLC Leather Technology Center
USDA Regional Research Center
American Institute of Pipe Organ Builders www.pipeorgan.org
American Pipe Organ Builders Association (APOBA) www.apoba.com
American Theater Organ Society www.atos.org
Mechanical Music Digest (MMD) www.foxtail.com
Mechanical Music Press www.mechanicalmusicpress.com
Music Box Society (MBSI) www.mbsi.org
Organ Historical Society www.organsociety.org
Pipe Organ Builders www.albany.edu/piporg-l/builders.html
Player Piano Care www.player-care.com