Removing Stains from Raw Leather

Leatherworking can be very rewarding but sometimes when we least expect it we can be blindsided by something that happens to our project. I have had this happen to me a number of times over the years that I have been doing hand-tooled leatherwork. I can tell you that it is not fun when you have to redo a project that you have many hours completing in the first place.

I have had well-meaning people pick up a project to look at it and leave fingerprints on it. It is a little like Steve Urkel from the old TV show asking, “Did I do that?” People do not realize that oil and dirt get on their hands even if they have not been working on their car or lawn mower. I have had fingerprints on leather that would have probably been good evidence in a criminal case. In some cases, it does not mean that all hope is lost, just that you might have to do a little cleanup to get rid of the spots. By the way, most of the fingerprints were probably my own.

I mentioned in a post a while back that there is a product that can be used to get rid of most stains on the surface of unfinished leather. “Unfinished leather” is the raw leather, whether stamped or not, when it has not been treated with a lacquer or acrylic finish or oil. The product of which I am writing about is Oxalic acid. Depending on who you might talk to or which web site you might visit, you might find it being called “wood bleach” or “leather bleach.”

I really do not care what you call it but you may have to do so research to locate a supplier in your area. The oxalic acid that I purchased came from a pharmacy approximately forty years ago. It came in powder form and in a quart jar. All I had to do was mix it with water and make sure that I did not get too much powder in the jar to begin with. What I have seen for current suppliers of the oxalic acid is that some of the lumberyards might carry it for use with special projects. You might also need to sign your life away to be able purchase it because it is poisonous. You might need to tell the person selling you the product what you plan to do with it.

Now with that out of the way, a little goes a long way. I have a pint jar that I have used for many years to mix and store my mixed oxalic acid. I do not have an exact recipe for the mix, so I would recommend using one-half teaspoon for a half pint of warm water for easy dilution. Be sure to experiment on a piece of scrap leather before you use this recipe on a project that you have spent a lot of time stamping. The reason being is that oxalic acid itself will add some color to the leather. Making it too strong may strong may add more color than you would want.

Always wear rubber gloves when using oxalic acid. Use a clean sponge that you can dip in your jar to soak up some of the liquid. If you were to apply a bit of the oxalic acid mixture to a small spot on a piece of scrap leather, initially, it will look as if you had applied water only. After the spot dries, you will then notice how the color of the leather has changed on that spot. The best way to avoid the spotting is not needing to use the oxalic acid. When it is necessary to use oxalic acid, you do not want to apply it liberally, especially if you have done a lot of carving and stamping on the project. Getting the raw leather too wet can sometimes cause some of the deeper stamps to lose some of their depth, especially the background.

The other thing with oxalic acid is that you do not want to apply it to the stained area only. If it will darken the leather in the area where it is applied then you will want to apply it lightly to the whole piece of leather to eliminate the spotting. Bleaching out a stain in raw leather is a pain because it can change the look of the whole project. Imagine getting a dirty fingerprint on a project that had one or more overlapping pieces. To make everything look the same you would have to apply the oxalic acid to each piece of leather. This could create a lot more work, especially on a project with multiple layers such as a purse.

There are some stains that are almost impossible to get out of raw leather. Two of the worst stains that I know about are ink and blood. I believe I mentioned them in an earlier post but it does not hurt to give you a reminder. With that stated, there are some other “stains” that you will not be able to get out of leather as well. You will find that some leather comes with built-in stains or coloring that cannot be removed by bleaching with oxalic acid. I have had leather like that before and I tried to work around it or incorporate it into a portion of the pattern with a lot of stamping.

Raw leather is sensitive to light. I have had projects that I inadvertently left out where the light could hit them before I had the time to finish. One time I left a leather box unprotected that I had tooled, sewed, and babied along to get it all done for an award at a big rodeo. I put the straps around the box to make sure that it held its shape and I forgot to put the cloth covering over it before I left for the day. Enough sunlight came through the frosted windows to darken the leather. There were stripes where the straps were covering the leather, which prompted a complete dye job.

The photos below show my attempt to demonstrate what direct sunlight can do to leather. The photo on the top shows how I set this up. I cut a small piece of leather and placed it on top of a larger one. The second photo shows the after effects of the leather sitting out in the sunlight for a few hours. You can see the light spot in the center of the piece of leather. This one is not as dramatic as I had hoped it would be, but I can promise you that some leathers will almost sunburn.

Small piece of leather on top of larger one - sunlight demonstration

Leather after exposure to sunlight - notice the darkened area.

Sunlight is not the only light source that will change the color of unfinished leather. Fluorescent lights will affect the leather as well. The thing that you want to remember is that leather is skin and that it is much like our skin, it will burn. It may not be because of the leather being skin as much as it is the chemicals that were used in the tanning process. It is possible that it is those chemicals reacting with the light that causes the darkening of the leather. If you have some scrap leather, you might want to experiment to see if you can duplicate the results of my little test.

In summation, you cannot bleach out the darkened areas caused by light on leather. The best way to avoid having this happen is to keep it covered or if you are letting it dry, make sure that you check it periodically, cover it with something that will not transfer any color, or just turn it upside down on a clean surface. It might take a little longer for the leather to dry properly if it is turned upside down.

Leather is not photosensitive like film that we used to use in our cameras. It will take a few hours for light to have a major effect. Just a short anecdote about my leatherwork: Almost twenty years ago, I made a photo album for a man and it had a lot of figure carving on it. Figure carving is carving animals and objects such as a cabin or a covered wagon. (There are many other figures that can be carved; those are the only examples that came to mind while preparing this post.) 

Anyway, I had completed this photo album and was going to take it to the local shipping store when I noticed that there was a faint amount of color in the lacquer. I was quite concerned when I found it because I had been very careful about not exposing it to anything before I took it with me. What I had done was, I was working full-time at job, and I left the photo album in my pickup, inside a plastic bag. What I did not think about was that I had printed a receipt on my color printer and placed it on top of the photo album inside the bag. What I saw on the front of the photo album was a copy of my logo in in the lacquer finish. Fortunately, it was not so dark that it was noticeable to most people. I may have been the only one who saw it. At least I hope I was. Another lesson learned.

Let me know if you have any questions or comments. I would love to hear from you!

Have fun!

Finishing with Saddle Soap and Tan Kote

I might have gotten a little carried away with the photos and the descriptions in the last post but this time it should be a little shorter, maybe. I will try not to go into quite so much detail this time. The challenge for me when I am doing something like this is that I know what I am doing and it is difficult not to skip steps just for that reason. I think that it is very easy for anybody who has performed a task for many years to make sure that he or she has not missed a minute detail that could throw the trainee into a tailspin.

The last post covered the use of Neatsfoot Oil as a method to finish your project. It is a very good option to use on most “vegetable” tanned leathers. Leathers that are tanned using vegetable matter such as bark, roots, and other plant parts is referred to as vegetable tanned leathers. The brownish tint that is found in these leathers comes from the vegetable portion of the tanning mixture. Some companies have the word “oak” in the name of their vegetable tanned leather because they use oak bark a part of their tanning mixture.

I cannot tell you just how somebody came up with the idea of using vegetable matter in his or her tanning mixture. It might have been discovered unintentionally, in a fashion similar to Columbus discovering America, by accident. All I know is that somebody figured out the right mixture of chemicals and bark for tanning some great leather. I believe that the lightweight leather sample shown previously was tanned using less vegetable matter in its tanning process than the heavier weight sample.

The photo below shows another pattern sample that has been carved and stamped before anything has been applied to the grain. The container to the right of the sample is actually a form of saddle soap. In my shop, I have various forms of saddle soap that I have used in completing various tasks. I have saddle soap if the form of glycerin bar, sprayable liquid, and what you see below. This saddle soap can be described as either a cream or a paste. If you compare the description of other products on the market, either of the previous descriptive terms might fit this product.

Sample project before saddle soap is applied and saddle soap in the container

To apply this form saddle soap I used a piece of sheepskin, which I loaded up as much as I could. I used circular motions to make sure that the product was evenly distributed over the whole surface of the leather. When doing something like this it is important to make sure that any product you are applying to the leather is evenly applied so that the leather does darken more in some areas. Also, be careful not to rub the project with the sheepskin too long in one area of you project because it may cause darker spots to form as well.

The photo below shows how the sample project looked after I had applied the saddle soap to the grain side. Since this form of saddle soap is a bit creamy or like a paste, it is not difficult to apply. What I do not particularly like is the way it darkened the leather all over and gave it more of a flattened look. In other words, everything seems to be the same color. I also noticed that there is residue in the carved lines and a little bit in the stamped impressions as well. I will use this form of saddle soap on harness and saddles that have been around a few years but after seeing how the sample looked after application I most likely will not use it to finish my projects.

Sample with saddle soap applied - taken immediately after application was done.

I wanted to see how this sample would look if I applied Tan Kote on top of the saddle soap. I do not like the results of the combination of the two products together. I will admit that I am very biased in my opinion and I have the right the same as you. It may look absolutely beautiful to another person and I will not try to change his or her mind about anything. To me this sample looks very dull and some of the character of the tooling seems to be missing now. The photos below are a comparison between having a plain saddle soap finish to that of applying Tan Kote on top of the saddle soap. If I want a more natural look to the leather, I will more than likely stick to using Neatsfoot Oil.

Sample 12 hours after applying saddle soap

Sample after 12 hours - saddle soap with Tan Kote

Now, after the negativity concerning the use of the saddle soap on the sample project, I have to admit to two things. First, I believe that this is the very first time I had ever used saddle soap on a newly tooled project and if I had done it before I possibly would not have had this reaction. Second, I may not have waited long enough for the saddle soap to penetrate the leather completely before applying the Tan Kote. Somewhere down the line I might decide to try using the saddle soap on another sample project.

The photo shown below is again another sample with the same pattern stamped on it. The difference with this sample and the previous ones is that I made different decorative cuts on the flower petals and some of the leaves. This sample is done with Tan Kote only and it looks great as far as I am concerned. If you look closely at the some of the areas, especially the background,  you will see some spots that look a little white. The white effect comes from the Tan Kote having some air bubbles in it from my applying it with sheepskin in a circular motion. Some habits are hard to break. Do not get alarmed about the spots that look this way, it will disappear after the product is dried.

 

Sample immediately after applying Tan Kote to surface

Still another photo, showing the Tan Kote finished sample after sitting overnight for approximately twelve hours. The areas that looked white have disappeared because the Tan Kote has been absorbed into the leather and dried. I do like the looks of the Tan Kote on the leather because it gives the it a mellow finish rather than a shiny one. I do not like the shine of some of the lacquer finishes that I have seen in the past. I think that Tan Kote is a very good option for a finish coat on your project. 

Sample 12 hours after applying Tan Kote to the surface

What  I have tried to demonstrate with the samples in the last few posts is that the leather can be finished in various ways. It does not have to be shiny to look good and it does not require a lot of work to look make the finish look good either. The major requirement when finishing a project is that you make something the way you think it should be done and you finish it to match your taste. If you want to dye your belt green by all means, do it. Feel free to experiment with your projects, but try it on a sample first!

Let me know if you have any questions or comments.

Have fun!