Wednesday, July 1, 2009

Nubuck (brushed leather) and Suede Cleaning

Suede and nubuck are versions of leather with a nap. A common characteristic is that they are both highly porous. This means that any liquid spill rapidly soaks in. The result is generally a stain representing the coloring agent or solids after the moisture evaporates away. This means any liquid cleaner will be useless as it also will simply soak in. Leather cleaners resolve what is on the surface, not a stain inside the leather. A stain in nubuck or suede is sort of like a tattoo in your skin. You can't clean it off. The only exception is if the stain is made up of solids on the surface (like food particles stuck to the leather).

The professional leather technicians of Advanced Leather Solutions use a different technique.

Instead of using a "wet" cleaning strategy, we use dry abrasion or sanding technique. First some background. Nubuck is created by sanding leather which raises a nap. Suede on the other hand is the inside of the hide, not the epidermis or grain side. In either case there is a nap and it's porous.

When a stain develops, the dominant component of that stain is in the nap. The basic idea is to sand or abrade away the ends of the nap and re-nap simultaneously. As a technician, I use a variety of tools ranging from a nubby, stiff towel formed into a ball in my hand to a medium grit sanding tool. Most commonly I use either a soft-bristle nylon brush, or 400 to 600 grit wet/dry sandpaper.

Abrasion will remove the ends of the nap, any surface solids and free up the nap fibers. The technique often resolves the stain completely and at a minimum will lighten the stain, and restore the nap. In those cases where the staining agent is known to be solids on the surface of the leather, and to be water-soluble, then to pre-dampen the stain with a damp, white cotton cloth before using the abrasion method may have some effect. Occasionally, I will very carefully use the end of a razor blade to gently pick off solids that are stuck to the leather.

If you are using something with little abrasion capability, like a nubby towel, you can be aggressive in application. On the other hand, if you step up to a medium grit sandpaper, you must be very gentle in application. As a general rule, the more aggressive the tool, the lighter the application, else you'll leave score marks in the leather. Do not be overly aggressive. Here are some additional "Does and Don'ts."

---- Do not focus exclusively on the stain. Rather, blend to the surrounding areas.
---- Do not start with the most aggressive abrasion tool. Start with a light tool and gradually step up more aggressive sanding tools.
---- Do not abrade in only one direction. Move your abrasive material side to side and up and down.
---- Do not dive right in. Start in a non-obvious area first to see the effect of the sanding tool.
---- Do not expect perfection. Instead, the goal is to minimize the stain to the degree that it is far less noticeable from five feet. If that happens, be happy.

Expect some lightening of the leather. Success is dependent on the depth of the stain, and its chemistry. Caustic fluid like coca cola will leave a reference even after the stain as been resolved as it alters (erodes) the topography of the hide.

If the stain is not resolved with moderate effort, consider contacting Advanced Leather Solutions for advice prior to any more aggressive attempts. When completed, wipe that area with a dry white towel to remove any leather dust created. Do this several times, turning the towel to a clean section each time.

For instances where topical soiling or discolorations cannot be resolved with this methodology, please visit our services page, for more information about our leather repair and restoration services, and why cleaning alone may not be enough of a remedy.

Finally, know the distinction between real suede and ultra-suede. Ultra-suede is a synthetic and is generally very thin. If you aggressively sand ultra-suede, you'll quickly sand through the material.

Copyright 2009 Kevin Gillan

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