How to maintain & repair your leather....

Leather: Theory

   Leather is basically skin. Like skin, leather requires oils to keep it supple and soft, flexible and to keep it from chaffing and cracking. Unlike live skin, leather doesn't get renewed from below, nor does it produce it's own oils to maintain itself. Most of the treatments for leather are very similar to the equivalent processes for skin: gentle soaps for cleaning, conditioners (think hand lotion) for keeping it from drying out, etc.

Leather: Maintenance

   Leather has several stages of maintenance that you will want to do to keep it in optimal condition:

• Sealing: Sealing is the act of making leather waterproof, such as boots that you will walk through puddles with. It is also useful for leathers that are used in car interiors (to help keep that spilled soda from soaking in), and for leather used on motorcycles (because it sucks to sit on a soggy seat, or have your leather saddle bag contents get wet). Moreover, sealing generally provides some method of sealing up the seams at the edges of the leather, as well as holes where the leather has been perforated, such as where different pieces are sewn together. Sealants come in a few varieties and a heap of different brand names. For items where surface oil exposure isn't critical (outside of jackets, etc), or where the product will have at least a day to absorb it, we tend to recommend products that are high in mink oil content (such as Kiwi brand Mink Oil treatment), because mink oils are particularly good at moisturizing & softening the leather at the same time as it seals it. For surfaces where possible oil-transference becomes an issue, especially when the item will be used immediately after sealing, we recommend bee's wax based sealants instead.
   
  - When to seal leather: Seal leather when you first acquire it, and whenever it demonstrates a tendency to absorb water-based liquids. If you need to strip or dye the leather, do those steps before sealing it.
   
• Stripping: Stripping leather is the act of removing all oils from the leather. By using a light petroleum-based solvent, such as zippo lighter fluid (Naphthalene usually), the oils & sealants in the leather are removed, exposing the raw leather below and prepping it for dying.
   
  - When to strip leather: This process is only used if the leather has a plasticized layer (when new) that would prevent a sealant (such as mink oil) from being absorbed, or when leather (used/aged) is discolored and needs to be dyed or redyed.
   
• Dying: Dying leather is the act of permanently staining (or restaining) leather to a specific color. Note that the leather must be stripped first for the dye to take readily. Leather dyes are available in a wide variety of colors, but normally can only be dyed to a darker color or back to the color it original was dyed (in cases of redyeing). Because of past experiences using it, we recommend Kiwi brand leather dyes, which are often available at grocery stores (at least in black) and shoe cobbler shops (in most colors).
   
  - When to dye leather: If you have a light colored leather and desire to alter it's color (such as making white leather red, or brown leather black), or when you have aged/worn leather where the color has been scuffed off (such as on boots, seat bolstering, seat bottoms). You must strip the leather before dying in order for the dye to absorb properly. Note also that after dying, you must reseal the leather, and any portions unsealed (such as the inside of combat boots) may leak the dye out when exposed to human body oils or sweat.
   
• Conditioning: Conditioning leather is the act of adding oils, waxes or other moisturizers to leather in order to keep it supple and healthy. Dry leather will crack when flexed (such as the seat of you car flexes when you sit in it), while properly moisturized leather will flex without damage. If the leather is clean and sealed and has previously been conditioned, you can apply additional conditioner directly to the leather without any other prepping. If the leather is dirty, you should use a leather cleaner first to remove the dirt. Note that leather conditioners will often darken the appearance of most leathers.
     There are a large number of leather conditioners on the market, with varying characteristics. Some excel at making the leather soft & well oiled, while others are better at adding a combination of a little bit of oil and a lot of wax (which helps keep the leather hard, but still protects it). The one thing that you will probably want to avoid is products with significant amounts of silicone or any petroleum products in the conditioner, as silicone & all petroleum products do not actually provide any true long-term benefit to the leather (they are not proper moisturizers, instead simply adding a film that makes the leather appear shiny -- but do not preventing from drying out). You can, however, substitute a good quality hand lotion or pure lanolin if you don't have access to, or desire to use, a leather conditioner.
   
  - When to condition leather: Any time you want, plus whenever your leather starts to become excessively dry or hard. For car and motorcycle seats, we recommend doing so at least once per month for best benefit, more often in hot and dry environments (which cause the leather to dry out more quickly). In general, you can not over-condition leather no matter how much conditioner you use. Remember: cracked leather can not be uncracked (only redyed and replaced). If the leather is dirty, use a leather cleaner first. If the leather is worn, consider whether to strip, dye, seal and then condition the leather as an entire process to renew it.
   
• Cleaning/Soaping: Cleaning or soaping leather is the act of washing the surface of the leather to remove dirt, stains and excess oils (specifically ones which are retaining dirt or discoloration). Although there are a large number of products on the market for cleaning leather, we recommend using saddle soap (available at any grocery store in the shoe polish section) and following the directions, unless you are specifically trying to remove a certain brand's conditioner (in which case you should probably try that same brand's cleaner product). Note that the act of cleaning the leather is not the same as the concept of washing leather, but rather more akin to placing a foam or froth of gentle detergent on the surface -- you're not trying to soak the leather, but just clean the surface. Permit the excess liquids to dry before applying the conditioner after cleaning/soaping, and ALWAYS apply a conditioner after cleaning/soaping.
   
  - When to clean/soap leather: If the surface of the leather has a discolored conditioner, motor oil, dirt, or other contaminants on it that can't simply be brushed away, clean/soap it before conditioning it. Using just a conditioner instead of cleaning it first will effectively trap the contaminants under the conditioner and expose the leather to it for a long period of time (which is not a good thing).
   

Leather: Repair

   The good news is that lightly damaged leather can be treated to prevent it from damaging further and can be colored to match, to one degree or another. The bad news is leather that is heavily damaged must be replaced (either the damaged section or the entire piece) to be reliably repaired. If the leather is lightly cracking, but has not cracked all the way through yet, strip it, redye it to the same color (since the inside of the cracks will be the color of the raw leather and not the color of whatever dye was used previously), seal it, condition the hell out of it and then keep it well conditioned, to keep the remainder of the leather from giving.
 
   If the leather has cracked all the way through, there simply is no good method for correcting it shy of replacing that piece or segment of leather. Most leather and most upholstery shops can match a single section of leather at a reasonable price, including sewing in the replacement piece (if you do the dying, sealing and conditioning, the price will be even cheaper). I have heard tales of small holes being repaired with vinyl repair kits, but I would consider this only a temporary patch, since (a) the application requires heat, which will damage the surrounding leather, and (b) to keep the leather oiled/conditioned will cause the bond to the vinyl patch to disengage (since the vinyl can't hold on to an oily surface, and if you don't condition the leather, it will fail).

Leather: Products for Maintenance/Repair

We recommend the following products for certain uses (listed) based on personal experience and do not receive any financial reward for doing so.

• Kiwi Brand Saddle Soap: a good, general purpose soap for cleaning leather. It is gentle, easy to work in, inexpensive (under $3 a container), and available at virtually every grocery store. Contains some oils to help prevent the saddle soap from acting like a stripper.
   
• Kiwi Brand Leather Dye: Note that there are various types of this dye under this brand. The most effective ones we have found are in a glass bottle with a small foam brush attached to a wire retainer in the inside of screw-on lid. We've had less success with the type that have a foam applicator on the exposed tip of the plastic bottle. I don't know if the difference is in the formulation, or simply the applicator, but the results did vary greatly as a result.
   
• Kiwi Brand Mink Oil: Works well, but contains some silicone. Easy to work in, inexpensive (under $4 a container), and available at virtually every grocery store.
   
• Mink Oil Brand Mink Oil: Works well, but like the above, contains some silicone. Easy to work in, inexpensive (under $4 a container), and available at camping goods outlets.
   
• Kiwi/"Camp Dry" Brand Silicone Water Repellent (spray): Contains a high amount of silicone, but is very effective as an initial sealant for new leather, especially leather that is expected to face the elements (boots, jackets, saddle bags).
   
• Kiwi/"Camp Dry" Brand Neatsfoot Oil (liquid): A heavy oil useful for raw leathers, untreated leathers, and for smoothing and sealing suede (will make suede look like regular leather and flatten the raised surface). 100 years ago, it was made from oils present in the lower bones of cattle, but these days, you never know with the big commercial brands. Will discolor any light to medium-dark leathers to a significantly darker color (tan suede will turn to a earthy darkish brown). We do not recommend it for surfaces that will contact bare skin regularly. But if you're thinking about throwing out that old suede jacket, try wiping this stuff on liberally and allow to penetrate for three or four days before reconsidering -- you'll probably be very amused at the results.
   
• Equimins Neatsfoot Oil (Pure) - liquid: A heavy oil useful for raw leathers, untreated leathers, and for smoothing and sealing suede (will make suede look like regular leather and flatten the raised surface). Still made from cattle bone oils the old fashioned way. Will discolor any light to medium-dark leathers to a significantly darker color (tan suede will turn to a earthy darkish brown). We do not recommend it for surfaces that will contact bare skin regularly. But if you're thinking about throwing out that old suede jacket, try wiping this stuff on liberally and allow to penetrate for three or four days before reconsidering -- you'll probably be very amused at the results.
   
• Lanolin: The natural oil of sheep, recovered from the sheered wool when it is processed. You probably know that wool shrinks when it gets wet, but for some reason sheep don't have their coats shrink. So what's the deal? Their skin produces a heavy oil called lanolin that is water proof and supremely wonderful for skin (which is why you find it in many hand and skin lotions). It is also very useful on leathers to seal them and condition them. The correct way to apply is to smear it on, allow to soak for 2 - 7 days and then buff off any excess. Note that lanolin can easily transfer to cotton, permanently oiling it as well (think Australian-style dusters -- lanolin soaked cotton), so if you use it, be sure the surface has had the excess removed before sitting on it or letting clothing rest against it.
   
• Lexol Leather Conditioner: Useful for places where the leather is used for seating, or where the leather is not to be permitted to become too soft lest it loose it's shape (such as formed leather products). Not suitable for very soft leathers, such as gloves or suede. Leaves a waxy feeling on the leather (rather than an oily one).
   
• Lexol Leather Cleaner: Useful for sealed leathers, especially where the leather has been treated with Lexol Leather Conditioner, and in thin leathers. Will not help impart an aging patina to leather, which may or may not be desirable, depending on the application. Not as astringent in cleaning as some competing products.
   
• Sno-Seal (Beeswax leather sealant): Useful for brand new leather, especially at the seams. Unlike oils and silicone, beeswax does not migrate through leather quickly, nor does it wear down/wear away (except by contact rubbing). A great first step in the treatment of any leather you want to stay truly waterproof (such as motorcycle seats/saddles).
   
• Zippo Brand Lighter Fluid: Naphthalene or equivalent. Petroleum based lighter fluid, will displace sealants, oils, waxes and is suitable for stripping leather, but still gentler than most paint solvents and other forms of stripping agents. Under $5 a bottle -- use sparingly (one advantage of lighter fluid bottles -- they have little pour nipples to help insure you don't totally soak the leather).