Dried Out Wetblue: Wetback

Sometimes we find that our crusts become hard no matter how much percentage of fatliquor was added.  This could be due to improper wetting of the wetblue leather.  We depend on water as the median for chemicals to do their job by penetrating and reacting with the fibers.

If water does not penetrate the crosscut fully, the chemicals which are miscible in water would not penetrate as well.  The chemicals will either superficially fix on the very top layer of the wetblue or remain dispersed in the bath.

Solution

Alchem CSAM and Alchem325W are designed for this very purpose.  They assist the water uptake and penetration.  They do not cause leather to become loose or harden after storage.  Alchem CSAM will equalize the pH of the entire crosscut.
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Useful Tip

Avoid the use of oxalic acid as much as possible.  This is due to the de-tanning property of oxalic acid, causing coarse grain.

Time

Time is another important factor.  In extreme cases, the wetblue can be left in the wetback bath for more than 24 hours.  Note: soaking in water for a prolonged time will not have any detrimental effect on the wetblue.  Alchem CSAM and Alchem325W continue to work as long as they are in the bath.

Split Suede

For split suede, butt areas sometimes have deeper blue color and are very coarse to the hand.  These are troublesome areas because after treatment, they remain hard and coarse due to incomplete penetration and fixation of chemicals.  Slightly buffing the surface with sand paper could sometimes help.
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See Some Examples