PROCESS FLOW SHEET

Raw Through Blue
The first nine steps in the wet operations prepare the raw hide material for sale "In the Blue."  During this process, which requires approximately 16 hours (half as long if hide material is received fresh), the hide is rehydrated, dehaired, and converted into a stable non-putrescible material.  Excess moisture and extraneous components (i.e. long shanks) are removed, the hide is sided, then split and shaved to the requisite thickness for end product manufacture.  Often, the split and shave process is completed at the upper tannery (the receiving facility).

Crust
The combination of steps 10 through 16 (re: Process Flow Sheet) allow the upper tannery to produce a leather specific to the requirements of the end product manufacturer.  Retanning is completed to render special end-use properties using specific tanning chemicals, color is then added, followed by fatliquoring which imparts flexibility and softness.  Leather at this stage is referred to as "crust".

Drying after coloring or dyeing can be carried out in various ways.  It is important because it must reduce the water in the leather from 80% to about 10%.  First of all, the leather is almost always set out to compress and squeeze out excess moisture and then one of the following systems is used:

  • Hanging
  • Pasting
  • Toggling
  • High frequency vacuum drying

Once dry the leather must be wet back, or conditioned, in preparation for the final mechanical softening, or staking.  Buffing of the grain surface is the last step prior to finish.

Finish
The final four steps in the process, referred to as "finishing," require the skill of the creative mind.  It is at this juncture where the product's natural beauty can be enhanced while at the same time serviceability can be improved.  Through the plating process appearance and hand can be even further enhanced.

Finally, the leather cycle is completed through grading and measuring of the finished product.  Grading is a critical task which ultimately ascertains the effectiveness of the tanners quality controls and is still today completed by hand.  Measuring, however, is carried out by automated precision systems.

One particularly outstanding resource for the entrepreneur interested in a user friendly overview of the leather process is available from the New England Tanners Club for a nominal fee. 

This Resource is entitled "Leather Facts," copy requests may be made to: 
New England Tanners Club, P.O. Box 371, Peabody, MA 01960.