Gosut

...That I like leatherworking, but thinking of doing a sheath in Kydex?

Some imported veg tan leather. No real brand. I'm a beginner and don't have the skills for the expensive stuff yet.

Decided to dunk the leather again. First I got it soaked, then put it in a folded paper towel. No bleeding. Next I let it soak. Then had some bleeding into the water. Again wrapped the scrap in a folded paper towel. No bleeding on the towel. Not sure what to make of all this.

Strictly as a user of leather goods, the wear and tear on leather seems heavily dependent on customer care. I've seen a WWI US Calvary saddle that was heavily used in civilian hands that was in good shape after a century. Our family no longer has the mule harnesses because they deteriorated long ago. The leather on shoes much younger than that gave up the ghost, but most of these were work shoes subjected to hog lots. My grandfather's razor strop is still around, but would be reluctant to strop a blade on it due to its fragility. Let's say someone offers a century guarantee. After a year they get a claim because someone didn't take proper care of the item. Then what? Say "This is due to your negligence," which is the truth, but is likely to get the complaint going that you don't honor your guarantee? Replace it no questions asked, then end up hemorrhaging time and money with questionable claims?

Not picking on Vinegaroon here. Dunk regular tanned leather in water, and it will bleed. Have discolored socks over the years that attest to this. I had hopes for vinegaroon, though, given it turns leather black through a chemical reaction. I tested it on a scrap that turned as black as coal, neutralized it with water and baking soda, and noticed some bleeding. Rinsed and resoaked with more bleeding. Placed it on a folded paper towel, and it wicked away bleeding. At this point I allowed it to dry and soaked it in steeped tea to add back tannins destroyed by the baking soda, then rinsed and soak. Had bleeding, but it could have been from the tea. Rinsed and soaked again, with more bleeding. At this point I stopped and allowed the scrap to dry. At no point prior to exposure to water did the scrap display rub off. It's only on exposure to water. Is there a way to prevent bleeding? My concern is sweat. I know I 've had belts over the years that got throughly soaked in sweat and didn't bleed, but I assume they were chrome tanned. Then again, there's my experience with boots and shoes.

Interesting. This tannery seems to use a combination chrome / veg tan process. They didn't show them breaking the hides. Does that mean chrome tanned hided don't need breaking? Sticking the hides to glass looks like an clever way around tacking a hide to a board or lacing it to a frame during drying.

Was surprised to find the orange ring is gone this morning. The liquid is still pale yellow, cloudy with a white precipitate. There is white precipitate at the bottom. The bottle showed more bending inwards, but it's also about 30° F / 17° C cooler. It seems to imply a change to maybe ferric acetate, but then to something else. Since most of the things in the bottle are iron, acetic acid, water, and oxygen, whatever is going on has to involve iron, carbon, hydrogen, and oxygen. That limits the possibilities. Though not part of the experiment, I did neutralize the free acetic acid in the test strip. Also discovered the black color bleeds. Since it's a test strip, need to just let it soak in water to see if it reaches a point where the bleeding stops, and, if so, if the leather is any less black.

Mine is headed that way. The orange is a ring around the top. When I gently shook it this evening, there was a rain of white precipitate from the top. Interesting, the plastic 2 liter soft drink bottle has the sides bending inwards, as though the air at the top is less Temperature is about the same as yesterday, as is the barometric pressure.. My assumption is this is some sort of oxidation. Whatever it is, it's combining with something in the air.

I thought it was at an end. The vinegaroon now has a layer of orange floating and seemingly slowly descending from the surface. I suspect this is oxidation. It also had a white precipitate in the bottom. I suspect it has to do with pouring it through the coffee filter, either some sort of oxidation reaction or with the filter itself. Again, it was clear before I poured it. Will watch it, but in the future, would rather make it as needed than make a large batch and have it go bad.

Have made a grand total of two. One was more of a quarterstaff than a walking stick and broke. The other, in my teens, was closer to a small fence post. These days I prefer an eye hoe handle. These are 54" / 1.37m long and maybe 1.25": / 3.175 cm in diameter. I put a rubber non-slip chair leg cover on my latest, to protect the end.

Finally, an End to It The test scrap is dry and is as black as coal. May try neutralizing the free acetic acid in a solution of baking soda, followed by a dunk in some tea to replace lost tannins, followed by a rinse. Don’t know. Will be subjecting it to some bleed tests, to see if any of the black seeps out when the leather is wet. That’s beyond the scope of this topic. I went back over the calculations from scratch and came away even more confused. My first set of calculation may be the closest to correct. Here’s why: Once again, the formula for iron and acetic acid is Fe + 2(CH300H) = Fe(CH302)2 + H2. This means that it takes 1 iron to react with 2 acetic acids to make 1 ferrous acetate and 2 hydrogens. Chemistry uses moles to make calculations more convenient, so we can say it takes 1 mole iron to 2 moles acetic acid to make 1 mole ferrous acetate and 2 hydrogen. A mole of iron is 55.845g and 2 of acetic acid is 2 x 60.052 = 120.104g. I first figured the amount of acetic acid in vinegar by reading an FDA regulation and assuming acidity is by weight / volume. Liquid acetic acid has a density close to that of water, 1.049g/ml, though. If we work it out with acidity as volume / volume, then 5% acidity for 1000 ml = 50 ml acetic to 950ml water. So, 50ml x 1.049 = 52.45g per 1000 ml. 52.45g / 60.052g/mole = 0.873 moles acetic acid. If we have 0.873 moles acetic acid per liter of vinegar, then that would react with 0.873 / 2 moles iron = 0.437 moles iron. 0.437 x 55.845g = 24.404g iron per liter of vinegar. For two liters 5% acidity white vinegar, 24.404 x 2 iron is needed = 48.404g. This is close to where I started. As a quick check, the ratio of iron to acetic acid is 55.845/120.104 = 0.465 x grams of acetic acid. For 104.9g acetic acid, we would need 104.9g x 0.465 of iron = 48.779g. That means 48.404g is in the right neighborhood. This means my 49g of iron wasn’t way too much after all. But it also means that in two weeks a significant amount remained. That meant there was very little ferrous acetate in the solution I poured into another bottle. It also means that it takes very little ferrous acetate to react with tannic acid to give that nice black color, and that there’s an awful lot of free acetic acid in the solution. There are some other things I want to try, but this experiment is at an end. It’s also a failure, in how much iron is needed to react with all the acetic acid. That went off the rails when it pushed vinegar out the vent cap and I started topping it off. At best this is a learning experience in how not to do this sort of experiment. It also suggests that the iron should be well below the surface of the solution to prevent oxidation.

This afternoon noticed the steel wool floating and the neck was free of liquid. Went ahead and poured. The liquid in the bottle was clear, the steel wool gray. I poured it into another 2 liter soda bottle, using a coffee filter and a funnel. Toward the end, the filter had picked up enough steel wool particulates that I had to change it. Think this was off the steel wool itself. Pouring the vinegaroon took about half an hour. During this time I poured a small unfiltered bit in a quart ziplock bag, just enough to cover a scrap of 3 oz veg tan on both sides. Let it sit while I finished. I was nearing the end when I noticed the bottle, now filled mostly with steel wool and a little liquid, felt warm. Wondered if it was my imagination. Set it down while liquid filtered into the second bottle and picked it up again. It wasn't my imagination. There was a definite warmth. Not good. Fortunately, I was just about done and I when finished, I cut open the bottle (wearing vinyl gloves for all this) and removed the steel wool. There were clear signs of rusting that had not been there before I started pouring. It had oxidized that quickly in air and the heat was likely due to oxidation. Squeezed it out best I could and disposed in an airtight container. The vinegaroon itself has a slight yellow tint. However, it's cloudy now where it wasn't before. That may not bode well. The test strip of leather looked black after about 20 minutes. Removed from the ziplock bag and set aside to dry. Don't know if I'll just rinse it later or neutralize any remaining acetic acid.

Right now I'm just waiting a few days to pour the liquid into another bottle. The liquid still shows no signs of orange and the steel wool no sign of rust. Plenty of bubbles. No sediment. This leads to a concern: H2. My initial thought was that H2 production would be slow, dissipating through the hole in the cap. In keeping the bottle full, there's not much room to collect in large quantities, though I have gotten the aforementioned liquid coming through it as the H2 collects on the steel wool. I'm not comfortable with H2 collecting at all. I've seen lead acid batteries explode, courtesy of H2 and a short between plates. This is something different, but the Wikipedia article on H2 doesn't inspire confidence. It's possible that I'm worrying about nothing, but how much H2 was in those lead acid batteries? And you can get an electric charge on plastic and even glass. courtesy of static electricity. I'm thinking of trying this on a much smaller scale with a wider mouth container, one open and the other with a layer of oil on top. It's frowned on now for environmental reasons, but putting a thin layer of oil on standing water is one way to control mosquitos by preventing the larva from being able to breath air. I think a little mineral oil is sometimes poured down seldom used drain traps to prevent evaporation, which would allow sewer gasses to come through the drain. But this would introduce another worry: The effect of H2 on the oil, in this case neatsfoot oil. I think a catalyst is needed for hydrogenation, though. H2 bubbles should pass through the oil. Maybe. Could try it with vinegar and a little baking soda first. I discarded the paper towels I had underneath the bottle. It had a tie-dyed orange look, but the last spillage had some dark gray. Fine iron can oxidize quickly enough to be a fire hazard. Even steel wool can be touched off if you're not careful. Again, probably worrying about nothing, but better safe than sorry. The fresh paper towels beneath it haven't had any spillage on it yet. Now I need a project to try it on. A simple one would be Yet Another Checkbook Cover. I would like to start on the knife sheath idea that started me in leathercraft, but I need to see about replacing the range hood before I buy more leather. Initial plan is to cut, glue, dry, then dye with vinegaroon prior to punching the stitching holes.

Even failed experiments teach something. To minimize surface area to air, I fill the 2 liter bottle to the neck. From the start I observed liquid coming out the vent hole in the cap. First I assumed that it was trapped air pushing up some of the steel wool, making it act as a plunger. But in subsequent fillings, the steel wool hasn't been near the neck of the bottle and have still observed the same effect. I think it's the hydrogen displacing the vinegar. Because I have 49g steel wool crammed into the bottle, I think it's making it harder for the hydrogen bubbles to float to the top. Twice now I've bumped the bottom of the bottle, releasing bubbles but no more liquid, and ended up with a clear space from the cap down to the main body of the bottle. It had already pushed the vinegar out the cap, but because the hydrogen bubbles remained attached to the steel wool, the bubbles didn't rise to the top. Instead, it pushed out liquid. Topped it off again this morning. Wondering if I should just wait a few days then pour the liquid in another bottle and discard the remaining steel wool and try again with smaller quantities.

Rusted iron is ferric oxide. Iron and water rusts, but I'm unclear if it's due to free oxygen in solution in the water or the water itself. If it's the water itself, it has to produce H2. My assumption is that it's due to oxygen in solution, but it's only an assumption. The acetic acid in vinegar reacts with iron to produce ferrous acetate. That''s what reacts to the tannic acid in the leather to produce black. There's iron loss, but it's not due to oxidation.

Important Update: I have made a huge, wasteful, error. It first occurred to me that I was stupid in not weighing the steel wool and vinegar mix. If there was no spillage, any decrease in weight would be due to the release of hydrogen. So, noting the decrease in weight over time, would both measure the reaction and allow the calculation of how much ferrous acetate and remaining acetic acid was in the bottle. That’s assuming the decrease was enough to be detected on a kitchen scale. Two liter bottles are unwieldy, though, so I thought of scaling it down to a half liter. It was then that I discovered I wasn’t just merely stupid, but incredibly stupid. By the chemical equation, it takes 2 moles of acetic acid to react to 1 mole iron. The molar mass of acetic acid is 60.052g, and with 5 grams acetic acid to 1000 ml of water in 5% white vinegar, that’s 5/60.052 moles. That means, with 5% acidity white vinegar, there should be 0.0833 moles acetic acid. Since it takes 2 moles of acetic acid to react with 1 mole of iron, it would take 0.833/2 moles iron = 0.0416 moles iron. The atomic weight of iron is 55.845, so 0.0416 x 55.845 = 2.323g of iron. For 2 liters of 5% acetic acid, that’s 4.646g iron. And I put 49 grams of iron in that two liters of 5% white vinegar. No wonder it looks like most of the steel wool is still there; it is. I miscalculated by an order of 10. It would take more than 20 liters of 5% acidity white vinegar to dissolve it all, and that's if the iron reacts to all the acetic acid. I can forget about measuring the decrease due to producing hydrogen. One liter of 5% acidity white vinegar reacting to iron should produce 0.0416 moles H2. But here I’ve made another error: I remembered gases like hydrogen like to stick together, so there’s H2 and O2, but a mole of hydrogen is still one H. So it should produce 0.0833 moles hydrogen. Multiplying that by the atomic weight of hydrogen and it comes up with a loss of 0.0839g for a liter. For half a liter, that comes to 0.0420g. It would take a very sensitive scale to detect that, and a kitchen scale isn’t going to cut it. Where does that leave us? Nowhere. As an experiment, this is at best a learning experience. I can still used the vinegaroon in that 2 liter bottle, just it’ll take maybe at least nine more fillings to use all the iron. That’s a lot. On the other hand, it seems that it takes only a small amount of iron to make ferrous acetate from vinegar. I still don’t know if it’s possible for the iron to react with all the acetic acid, but given accounts of vinegaroon reacting with baking soda even when there’s surplus iron in the jar, I’d say that’s a no. But remember, this is from the guy who miscalculated the chemical reaction by a factor of 10.

It depends on what you mean. As to how much combines with 5% vinegar, that's correct. As to the flaws in the experiment and what should and shouldn't be done, I've learned something. It's interesting to me that I'm not getting orange in the bottle, and the way to see if that's due to the small surface area exposed to air or keeping the steel wool submerged is easy to do. As to age, I'm in my sixties. As to education, went to college. Still make my living with electricity. Haven't had to use chemistry for that, and it shows.

As to chemistry books, I'm was about to crack open my college textbook, but then found one by Linus Pauling, General Chemistry. So far it strikes me more as high school level, but that's just three chapters in. Don't know yet why he covered calculating the distance of atoms in a solid, but wonder if he will tie it in with electrons and chemical bonds. Pauling's text is from the early 1970s, but figured that for the basic stuff, it should be fine.

As experiments go, this one has already gone off the rails. It's just steel wool, measured out on a paper plate on a kitchen scale, in a 2 liter plastic soda bottle filled with 5% acidity vinegar. There is no way to remove the steel wool except by cutting open the bottle. Didn't weigh the bottle before putting in the steel wool and vinegar, so I can't simply pour out the steel wool and weigh it. Even if I did, residual liquid in the steel wool would throw off the results. There's no way other than weighing the steel wool to determine how much dissolved, and the moment I take it out of the bottle and dry it, it's wet steel wool exposed to air, and will oxidize some. I didn't premeasure the vinegar before hand and have topped it off, so even that's out the window. So basically, I have steel wool in a bottle with vinegar and I look at it and go "Yep, there's bubbles on it and the liquid and steel wool shows no orange of rust (or ferric acetate - have learned that's a thing, too), It doesn't even seem to have significantly dissolved the steel wool in a week's time. That raises the question you brought up: How much ferrous acetate does it take to turn tannic acid black? If most vinegaroon leaves a significant amount of the iron intact, that implies it takes very little. At this point I could remove a tad with a dropper and see what happens to a piece of veg tan scrap, but that's about all. I don't know if I can even measure the tannic acid content in brewed tea to get some idea. Memories of titration keep coming back, but that means having some sort of indicator for what I want to measure and something that will react to it, not to mention a precise way to measure it. Am wondering if it would have been better to measure out a small amount of steel wool and vinegar. Doubt a kitchen scale could weigh a single 0000 steel wool strand, but just one with the predicted amount of vinegar might be better for this.

Thanks. I really am ready to dust off my old chemistry text book and start at the front. Have forgotten way too much of this stuff. This morning it looks like I may be getting significant dissolving of the steel wool. However, that could be shifting due to hydrogen forming on the steel wool and moving it around slightly in the liquid. Will wait and see.

I drive my wife up the wall with my insistence on using measurements when cooking. "I just add some salt," she might say ""But how much?" I ask. "How long do you let it cook?" "I don't know. I just as it until it looks right." That works well for her, but for a simpleton like myself, who only cooks on rare occasions, that's frustrating. I don't have the experience to know what "looks right." Same thing here. Like soap making, people were making iron liquor long before they understood exactly what was going on, and some of those old timers got mighty good results by eyeballing ingredients. But, like those soap makers of old, others got mixed results. Which is how homemade soap got the reputation of being harsh, because some ended up with excess lye. With vinegaroon, my question is the amount of free acetic acid, Ideally, an exact combination of iron with acetic acid should yield none, but I doubt that's possible with this kind of set-up. There will be some. If we neutralize it, we introduce sodium bicarbonate to the leather, but simply applying sodium bicarbonate might have bad effects on leather. Yes, I know free acetic and tannic acid would combine with the baking soda, but how much is left in the leather? So many unknowns. Basically, I want to understand what's going on chemically, and come up with a working recipe for personal use. Some of what I thought would work has already gone out the window, but that in itself teaches something. OTOH, so far there's no orange in the solution itself, so minimizing surface area exposed to air might help. OTOH, would have to do the same thing in a wide mouth container with the steel wool completely submerged in the vinegar to see if it's the smaller surface area or just keeping the steel wool away from oxygen.

Update: The vinegar has dropped slightly in the neck of the bottle, with no signs of leaks. That had me wondering how much drop would I see from the reaction. What follows is horribly slip-shod because I've forgotten the particulars about solutions. I'm going to have to break out an old chemistry text. My reasoning, slipshod as it is, is that the 46g iron that I used for calculations has a volume of 5.905 ml. Added to 2000ml of vinegar gives 2005.905 ml. The 100 g of acetic acid in the 2000 ml vinegar would be 95.829ml. So, 2000 - 95.829 = 1904.171ml water. If all the iron combined with acetic acid, that would give 144.865g ferrous acetate, which would have a volume of 83.544 ml. Added to 1904.171 = 1987.715 ml. 2005.905 - 1987.715 = 18.19ml drop in the vinegar. Again, note I've forgotten what little I knew about solutions, so these calculations may not be correct. It does look like my goal of keeping a minimal surface area exposed to air will mean topping it off more. I've already messed up this part of the experiment by adding vinegar to fill up the voids, so the result is going to contain more acetic acid than I hopped. OTOH, so far the liquid is clear.

The idea is that, in theory, if there's enough iron to combine with acetic acid, it should reduce the amount of acetic acid remaining in the solution to nothing. That's in theory. Actual practice is something different, though, and I don't know if this setup will result in all the acetic acid combining with iron. Likely not. I should have measured the vinegar as I poured it in, both to make sure I had the right amount and to make sure I had no air pockets in the steel wool. Since I had to add vinegar to make up the amount lost, as an experiment this is already a failure in that I won't know if it's possible to completely combine iron with acetic acid with such a set-up. Started wondering just how much hydrogen this should yield. By the formula, it takes 2 moles of acetic acid to yield 1 mole hydrogen. If there's 100g acetic acid in 2 liters of 5% acidity white vinegar, and the molar mass of acetic acid is 60.052g, then 100/(2X60.052) = 0.833 moles hydrogen. Hydrogen has an atomic weight of 1.00784, so H2 should have an atomic weight of 2.0157. 2.0157 x 0.833 = 1.679g hydrogen. Hydrogen has a density of 0.8988g/liter at normal temperature and pressure,, so 1.679 / 0.08988 = 18.687 liters hydrogen. If this calculation is correct (big if), that's a lot of hydrogen. Now I don't know if the displaced vinegar Friday was due to air trapped in the steel wool when it put it in the bottle or from the reaction. If correct, though, that yield of hydrogen shows why it's so important to allow the iron and vinegar mixture to vent.

Had thought about a higher concentration. White vinegar at 5% is easily available locally.

Update: Even with the cooler temperatures, there are now noticeable bubbles on the steel wool, with a bubble every now and then breaking free and floating to the top. So far, no orange in the bottle itself, so hopefully there's no oxygen getting involved in this. This is why I wanted to use the soft drink bottle, filling it up to the cap in order to reduce surface area exposed to air. Not quite ready to remove the cap and inspect the surface of the vinegar. There's problems with the bottle this full. A length of tubing attached to the top to lengthen the neck and allow for bubbles bursting at the top might be better, but don't know if it's possible to get such locally or if any exists in that diameter. Would have to cobble a connection. It would be very easy to spend a lot of money on this. I should have used a smaller bottle, since this is an experiment. Soft drink bottles seem to be stouter than plastic bottled water bottles, and would trust them more for this, even with the vent hole in the cap.