Wetblue thru crust

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The selection in the wetblue determines which type of finished product the hide will be destined to become. 

Shaving is accomplished by running the hide through a very accurate machine capable of thinning the hide to its’ final desired thickness. This machine operates with an accuracy of 0.1 mm (1/264th of an inch).

Re-tanning
The hides are reloaded back into drums for the next stages in their processing. The retanning modifies to some extent the characteristics of the original tannage. Oils, in the form of emulsions, are added to the retanned leather to give the desired levels of softness and drape. This is the operation commonly known as “fat liquoring”

These days there is virtually no limit to the colours that are possible using combinations the wide range of dyes available to the tanner today. With the brighter and stronger colours, problems of fastness can arise and, in selecting some of the more 'difficult' shades, care should be taken to ensure that the desired colours have adequate fastness properties to light. 

Drying
The drying of the leather is more than simply removing the moisture. Generally, it can be said, the more intensive the drying, the harder and stiffer the leather. Therefore the slower, more gently you can dry the leather, the finer and softer the finished product will be. This is goal of every quality upholstery tanner.

In order to produce a flat, smooth piece of leather, the hide must be held flat and in a stretched condition during the entire drying cycle. In olden times and in some of the worlds more primitive tanneries today, this is done by actually nailing the hide to large wooden panels during drying. 

An early improvement on nailing was the development of the “Toggling “ machine. On this machine, the hides are clipped onto large perforated metal frames which then pass thru a drying tunnel. The most modern and efficient method of drying today is “Vacuum Drying”. In the year 2003 Hulshof developed and installed (at a cost of approx. $1,000,000), a continuous vacuum drying system that is now helping us to produce some of the softest, smoothest upholstery leather in the market today.
 

After drying, the leather needs to be mechanically softened to relax some of the stiffness that occurs during any drying process. This is accomplished by first passing the leather through a machine designed to soften leather (“Staking machine”) and by then tumbling the hides in a dry wooden drum. 

At this point in the processing, every hide is once again inspected for natural range markings, color uniformity, thickness and general overall quality. This extra sorting insures that only the desired hides are used for every order.

The crust is now ready for finishing. Proceed to: Crust up to end product.