I posted this on another forum devoted to my car. Since I don't do that much auto work these days (mostly furniture), I thought I would distribute this to a couple of forums for everyones benefit.
The Definitive Guide to Cleaning, Repairing and Refinishing your leather!
I know I said that I was going to do this almost two years ago. I got involved with various things like South Beach Nap and this got put on the backburner. Sorry, but my problems with insomnia took precedence so I worked on a solution.
I have been involved with leather and the leather repair industry for ten years. I started out purchasing a well known franchise for the first five years. During this time, I received a basic knowledge of leather and vinyl. Despite this, I was not satisfied with the quality I was seeing and felt there was some more to learn. I decided to seek out other people and companies in the industry to see what else there was to learn. From my experiences, I was able to get a complete overview of the industry and find out what was good. I even went to work for one of the better chemical suppliers. I know a lot of people have had issues with the mobile tech industry or received a less than satisfactory job. Unfortunately, this is do to both the quality of the supplies being used and a lack of knowledge about leather and repair. Of course, a lack of desire to perform good work is sometimes apart of it as well. Having been around the country, I think I have seen it all. I hope this article gives you both a basic knowledge of repair along with the products that I use. Even if you don't want to perform the work yourself, you can use this information to your advantage when dealing with a mobile tech company or an upholstery shop.
In this article, you will read about the products that I use. I have tried just about every product on the market and I think these are the best. You may find others that work well, but I know that these will last. For leather coatings(dyes), I use Refinish Coatings. There are only a handful of major leather chemical suppliers in the world. Refinish Coatings is the distributor to the one that I consider the best out there today. The only other distributor of a major chemical supplier was(is) LRT. I am not sure what is going on with them lately or if they are still in business. LRT's coatings are(were) very good. Also, LRT had the added advantage of carrying around one hundred prematched colors. I know that a lot of people have tried other brands (as I have), but I don't think they are as good as these two. There is a strong possibility that the leather in your auto has one of these two companies coatings on it. Unfortunately, most mobile techs and upholstery shops use the cheapest stuff around or just go to Home Depot and make something up. For other stuff that you can't find at the local store, I use Mobile Tech Products. A lot of this stuff can be found at other vendors like Superior and VinylPro as well.
I will give a brief overview of the types of leather. Stainsafe/Leathermaster used to have a good description of the leather making process, but I can't find it online. The television series "Modern Marvels" had a one hour special on leather. This episode will probably give you more info on leather than you want to know.
When discussing the types of leather with clients, I use the analogy of painting and staining wood. Aniline, semi-aniline and suede/nubuck are considered unfinished leathers. In the analogy, unfinished leathers would be like stained wood. The leather is stained or dyed with no or little protective top coat. With this type of leather, you are touching the actual surface of the leather. Unfinished leathers are found mostly in expensive furniture or in rare cases automobiles. This is because of the lack of protection. The leather is easy to damage and in the harsh environment of autos it probably wouldn't last as long. It is also more difficult to clean. You can usually tell if the leather is unfinished by putting a drop of water on it. If it absorbs immediately, then it is unfinished. This test isn't fool proof though.
Finished or top-coated leathers are the other type. In the analogy, they are like painted woods. This type of leather has a coating applied to the top of the leather, so you are not actually touching the leather. The thickness of the coating can vary usually thinner for furniture and thicker for automobiles. The coating gives the leather more durability and protection. It is also much easier to clean. Finished leathers make up almost all auto leathers. Just because a leather has a top coat doesn't mean it is any less desirable. Most people prefer the protection and clean ability of finished leathers.
Cleaning and Conditioning:
This is the single most important step in keeping your leather looking the best it can be. Cleaning the leather will remove all of the dirt, body oils and grime that get onto and into the leather. This is what breaks down and destroys the leather. The products to be used are a cleaner, cleaning pad, and towels or rags.
For the cleaning solution, I use a formula that is used by one of the major tanneries to clean their leather. In a five gallon container, I mix 3% surfactant, 10% alcohol, and the rest water together. For the surfactant, you can use dishwashing liquid like Joy (I use something else, but I will keep that secret:)). For the alcohol, I use standard isopropyl alcohol that I get from the drugstore. For the water, I use distilled water. I was told that regular water is fine, but I would would rather not add anything else to the leather. Besides distilled water is inexpensive.
For the cleaning pad, I use 3M Delicate Duty scuff pad. It is the white one. It can be found at any drugstore or grocery store. The white, delicate duty pad is preferable to the more abrasive and common green pad. The reason is that the green pad can tear into the leather and scratch the surface.
For towels or rags, I use regular detailing towels. You can use just about any clean towel.
To clean your leather, you can either spray the cleaner directly on the leather or on to the pad. Lightly scrub the leather with the pad and wipe up the residue with a towel. You don't have to use much pressure as the pad will get down into the grain of the leather and pull out the dirt and grime. You can follow the cleaning by wiping the leather down with a clean wet towel. This will remove any cleaner residue that is left on the leather. If you see some color on the towel, then that means you are removing some of the top coat. Stop cleaning and change to water and the cleaning pad. The reason you may be removing some of the top coat can vary, so always check early. A full car should take less than thirty minutes to clean.
The pics are resized 2288x1712.
Being in a high humid environment like Florida, I don't use conditioner. The humidity keeps the leather from drying out. For those in a drier climate, you may want to use a conditioner. I have used Refinish Coating's conditioner, Lexol, and other brands. Most conditioners have lanolin as there main ingredient, so I would buy on price. The exception is Refinish Coatings and Lexol. Neither one use it in their formulation. A good cleaning is still more important than conditioning.
For those that have the real stiff leather, I have found that it is usually the coating that is the cause. If you want to try the rejuvinators, then that should be fine. If they don't work, then you may need to remove the coating. Someone told me what is in some of the rejuvinators, but I better not reveal what they said. It did get me to thinking that flax seed oil might be a cheaper alternative to the name brand products. I don't have any stiff leather to try it out on though.
The type of damage will determine the method to use to repair the leather.
If you have cracks or abrasions like on a bolster, then sanding and filling is my preferred method. The products used are palm sander, sandpaper, Refinish Coatings filler, and a pallet knife or razor blade. I will admit that I buy the RC filler more as convenience, as I am not sure it is better than others on the market. After cleaning, I will determine which grit sandpaper to use from 120, 220, or 400. I only use 120 if I find the coating difficult to remove and get down to the cracks. For deep or medium cracks, I will use 220 to start. On these type of cracks, I want to get through the top coat and lightly sand the crack smooth. I rarely sand the crack all the way down, so I don't remove to much leather. At this point, I will apply some leather filler with the knife or razor blade. I will wait between five and ten minutes before lightly sanding. The longer you allow the filler to cure the better. I have waited as long as a day on my own stuff. Repeat as necessary till the crack is filled. Once you have the cracks filled, I will finish with 400 sandpaper.
This pic is showing a finished crack repair along with an unrepaired tear:
For light or small cracks, I use the same method as above but I will not sand all of the way through the top coat before applying the filler. In this instance, I may lightly sand with 400 or use some acetone on a towel to partially remove the top coat. The acetone will flash off quickly and won't harm the leather. Just don't soak the leather with the acetone.
For abrasions like on bolsters, I usually start with 400. This will depend on how badly the leather is abraided. Most bolsters have sections where the leather is more worn than others. If it is heavily worn, the leather can be very thin. You can tell by pinching the leather to see if it is paper thin. To much sanding will result in burning through the leather. If filler is needed, then use the method above.
For tears all the way through the leather or holes in the leather, I use a slightly different method. The products used are palm sander, sandpaper, B-2 heat activated compound, Harbor Freight heat gun, pallet knife, VLP glue, sub-patch and chill bar. I have found the VLP glue at Home Depot and NAPA. I use the Harbor Freight heat gun, but there are plenty out there that are better like Steinel.
First, you should prep the leather in the same manner as with light or small cracks. Next, cut out a piece of sub-patch slightly larger than the repair area. Then put the sub-patch beneath the repair area. I put a small bead of VLP glue on the edges of sub-patch and press the leather onto it. This gives a nice base to apply the B-2. Now, I will use the pallet knife to spread out a thin layer of B-2 into the repair. I will wipe off any excess around the repair. Grab the heat gun. I will turn it on high and carefully heat the compound. The compound will turn dull and then glossy. When it is glossy, the compound is cured. Immediately place the chill bar on the repair to cool the area. Repeat the procedure till the repair is smooth and even with the rest of the leather. I will usually expand the last layer beyond the repair to help blend the repair. On leather with grain, you can place a piece of graining paper under the chill bar. Most of the time I am dealing with heavily damaged leather, so I have usually sanded it smooth.
A pic after sub-patching and glueing:
The final repair:
That is all there is to it. One final note is if the tear is near the seam or it is seam separation then the repair may not be able to be performed. You can give it a try. If it is unable to be repaired, then I tell the customer to replace the panel.
First, I know most people use the term dyeing or redyeing. I will use the term refinishing instead, as this is the term that is used in the leather industry. Mobile techs will still call it dyeing though.
The products I use in refinishing leather are a color computer, Astro HVLP 1.0 tip gun, air compressor, Harbor Freight turbine sprayer, hair dryer, masking tape, Gershon paint strainers, drop cloth, sander, sand paper and Refinish Coatings.
Now, onto the process. I start with taking a color reading with my computer. This gives me a formula to mix up to give me a close match in color and gloss. The ingredients in the formula are Top coat low gloss, Top Coat high gloss, crosslinker, and pigments. After mixing, I will strain the mixture twice to remove as much of the dry pigment flakes and crud. I like Gershon, because they have a fine mesh. You should be fine with the strainers from Home Depot. To get the match even closer, I will then do a correction. I realize most don't have access to a computer. I believe Refinish Coatings will do a custom color match. You can call and ask.
Depending on how much repair work was done or how much of the leather needs to be refinished will determine the amount of prep work. If the spot is small or there was very little repair work needed, then I may just use acetone to remove some of the top coat. Put some acetone on a towel and wipe the area a couple of times. You should see some of the color come off on the towel. This is what you want and will mean the leather is ready to be recoated. If the leather is more heavily damaged or is old, then you may want to go down to the base leather. As in the repair process, I will sand the coating and use acetone to try to get the old coating removed. Bare leather will be tan or light gray. These seats took forever to get the coating off. Once the leather is prepped, I am ready to recoat.
A prepped seat:
The first coat is with Refinish Coating's Base Coat. For a big job like the whole seat, I will use the turbine sprayer. If it is a small job, then I will use my Astro gun. Spray with light overlapping coats. The gun should be six to twelve inches away from the surface of the leather. After coating, use the hair dryer to cure the coating. Don't worry about over heating the leather, as the air won't be hot enough to do any damage. I will apply between two and four coats. The base coat will also partially fill in small cracks and imperfections. I finish this step by lightly sanding the base coat with 400 grit. This will smooth out any imperfections in the spraying.
Wet coated before drying:
The final coat is the Top Coat. Same application technique as with the Base Coat. It usually takes around four coats to get enough color on the leather. I will sand the top coat before I apply the last coat. This will insure that the coating is nice and smooth.
Lightly sanded before final top coat:
For a quick alternative, you may want to try ColorBond. It comes in a spray can and there are prematched colors. I am not sure how close of a match the colors are, but they are available. I have only tried ColorBond on hard plastic, but it worked really well.
Well that is all there is to it. I hope this has been helpful. The big decision will be whether it is better to just replace the covers or repair/refinish. This work is mostly time consuming, so you will have to determine if the time is worth it. If you have most of the big stuff, then consumeable costs should be less than $100. To do a whole car will probably take less than a quart each of base and top coat. The other stuff you can get by with the minimum quantities. In contrast, replacement covers from Katzkin and other vendors can be pretty reasonable.