Questions for Leatherworkers Regarding Vinegaroon

[Notchy Bob]

I've put it off too long, but finally decided for my next leatherworking project I want to try a more traditional method of coloring the leather.  Specifically, I want to try vinegaroon.

Mark Elliot wrote something about this on his website, and I considered emailing him but decided he's probably a pretty busy fellow and I didn't want to pester him.  I also thought some of the questions and comments might be of general interest to other forum members.

I understand that vinegaroon is a reagent, and not a dye, and it is made by letting rusty iron soak in vinegar, then after letting it percolate for a while, you use it to treat your vegetable/bark tanned leather, which turns permanently black.  It sounded simple.  I gathered up some old nails, rusty fence wire, and some rusty porch swing chain, gave it all a bath in a tin can half full of acetone to remove any grease, and then spread it all out to dry.  After the acetone evaporated, which didn't take long, I put the bits and pieces in a one-quart mason jar.  The iron pieces filled the jar about half full.  I then filled the jar to the neck with distilled white vinegar, shook it up, and put it on a shelf in my tool shed.  That was three days ago. I have shaken it a few times, and now the white vinegar is the color of cider vinegar.  I dipped a piece of scrap leather in it this morning, shook it off, and laid it in the sun to dry.  A couple of hours later, the leather was quite dark... sort of between charcoal grey and off-black, with a slightly bluish tint.  It looks like this stuff might just work...

Questions follow:

1.  Does it matter what type of vinegar you use?  I used the distilled white vinegar because I found some in the cupboard.

2.  How long should the iron sit in the vinegar for optimal results?  As noted above, my "batch" has only been percolating for three days, but it still reacted with the leather.  Is there an advantage to waiting longer?

3.  Should the solution be brushed on, or should the leather be dipped or immersed?  Also, is more than one treatment or application needed?  If the leather is immersed or dipped, how long should it stay in?  My test piece was only in the solution for a few seconds.

4.  Vinegar is highly acidic.  Should the acid be neutralized with a baking soda wash, or something similar?  I think Mark Elliott mentioned rinsing the leather after treating with vinegaroon, but I don't remember any specific details and I'm unable to find that article on his website again.

5.  Will the vinegaroon stiffen or dry out the leather, and is it customary to apply a secondary treatment, such as neatsfoot oil?  My test piece doesn't appear adversely affected, but it is pretty small.

6.  Are there any considerations I have overlooked?  My plan, in fact my usual MO, is to cut out the leather pieces, in this case for a shot pouch (AKA hunting pouch), color the pieces, and then stitch them together.  I prefer this to dying or coloring the leather after assembly, although my experience to date has been with commercial dyes. 

This is the outfit I hope to replicate:



I have a tendency to overthink some things, and in fact have occasionally gone into total "analysis paralysis" and ended up abandoning the project.  I'm determined to finish this one, though, and I believe I have everything I need, including the buffalo horn.  I want to thank everyone in advance for your helpful comments.

Best regards,

Notchy Bob

[RAT]

I tried making a batch last year. After sitting for about 3 months I got no reaction with the iron... at all. All I used were some small finishing nails. I only put in a few to see if they were being eaten. Nothing. I tossed the whole thing.

I read on this forum long ago that the % acidity of the vinegar was the key. The stuff I was using was 5%. I have some red wine vinegar that is 7.5%. I haven't tried it because I'm still using it for cooking. When it expires I might give it a try.

I experimented by wiping aqua fortis onto a small scrap piece. It instantly turned the leather gray-black. I was afraid to use it for a project thinking it was too acidic.

[Clint]

I think the vinegar recipie originates in the blacksmith shop. Freshly forged iron has a scale coating which is harder that the metal, and when files were hand made, smiths knew they could dissolve the scale in vinegar. A lot of steel hardening can be quenched in vinegar also. I make vinegaroon in a large plastic box with three or so gallons of vinegar. it makes filing forged parts a lot easier. In the process of making stain, I have found that cast iron makes for good color. I have completely dissolved many cast iron fence pieces and a couple  of cast lamp bases. If you have a good brew, there will be a lot of brown foam floating and a lot of iron sludge on the bottom. When I stain wood, I use the sludgy stuff for the initial coat and let it stand for a day or so. Scotch brite the wood off and do a second coat. Most vinegar will be around 5% and that's plenty. In the old days vinegar was made from apples but white works fine. I don't think you need to neutralize the leather because the acid is (gone?) after it dries. That's why flashing doesn't work with vin. If you want a little red cast to the stain, paint the piece with peroxide after it's dry.

[G. Elsenbeck]

Cider vinegar.

[MeliusCreekTrapper]

I have had good luck making vinegaroon when I clean rusty traps. I soak the traps in a 50 50 mix of vinegar and water for a couple three days. There is usually lots of foam on top. I'll keep a Mason jar of it for leather work. I have also had good luck using the metal filings from turning brake rotors at a mechanic's shop.

[Mark Elliott]

Questions follow:

1.  Does it matter what type of vinegar you use?  I used the distilled white vinegar because I found some in the cupboard.

I always use white vinegar that I get off the shelf at the grocery store.

2.  How long should the iron sit in the vinegar for optimal results?  As noted above, my "batch" has only been percolating for three days, but it still reacted with the leather.  Is there an advantage to waiting longer?

I keep a large container of vinegar and iron that I add vinegar and iron to as needed.   It takes at least a few weeks to get to a usable strength.   The longer it sits the better until the solution is saturated with iron.    I keep a large chunk of wrought iron in the solution.   I do blacksmithing, so I have iron as opposed to steel.  I just through something in there from the cutoff box.  I don't bother to clean it or anything.   The vinegar does that.

3.  Should the solution be brushed on, or should the leather be dipped or immersed?  Also, is more than one treatment or application needed?  If the leather is immersed or dipped, how long should it stay in?  My test piece was only in the solution for a few seconds.

I dip long strips and use a sponge to wipe on the solution for large flat pieces.  I make sure the leather is saturated through.  I stain before I assemble.  So,  I want to be able to cut the leather without having to restain.   I just keep adding solution  until the leather turns the color I want (dark blue-black) all the way through.  It will dry gray and then darken to brown/black when oiled. 

4.  Vinegar is highly acidic.  Should the acid be neutralized with a baking soda wash, or something similar?  I think Mark Elliott mentioned rinsing the leather after treating with vinegaroon, but I don't remember any specific details and I'm unable to find that article on his website again.

DO NOT neutralize.   Leather needs to be acidic.   The leather will dry rot quickly if you neutralize it.   I just stain the leather and let it dry.   It does get rinsed when the piece is finished when I either turn it or distress it.  I do that in a warm water bath.   Unlike oil stain, not much washes out.

5.  Will the vinegaroon stiffen or dry out the leather, and is it customary to apply a secondary treatment, such as neatsfoot oil?  My test piece doesn't appear adversely affected, but it is pretty small.

Yes.  I oil liberally with a good quality Mink Oil when the item is finished.   

6.  Are there any considerations I have overlooked?  My plan, in fact my usual MO, is to cut out the leather pieces, in this case for a shot pouch (AKA hunting pouch), color the pieces, and then stitch them together.  I prefer this to dying or coloring the leather after assembly, although my experience to date has been with commercial dyes. 

Sounds good to me.


Mark

[TN Longhunter]

Coming at this from a woodworking perspective, when I make it for staining wood, I use steel wool. Soak it three baths of acetone to remove oils. First bath gets tossed, second and third move up to 1st an 2rd for the next round. White vinegar soak for a week. Strain through cloth and store in sealed container. Will turn walnut black while still being able to see the grain.
I have been trying on brain tan scraps and get a gray/brown color. May need to make a new batch for a richer color, or just smoke it some more.

Don

[Arcturus]

Mark summed it up nicely.  At application the iron immediately turns the leather a bluish black.  That dries to a gray color that initially scared me the first time I used it.  But after oiling the piece it darkened to a dark, charcoal grayish black color, and smelled of vinegar for a while.  And slowly the smell fades and the color turns from grayish to brownish. Years later the first flint/tool wallet I made is now a very pleasing dark brown tone. 

[Marcruger]

I think that when a historic product works the best, it is great to use it.  I am thinking of Aqua Fortis, Tannic Acid, etc. on gunstocks and other wood.  I personally don't think vinegaroon is still the best way to dye leather, and I also believe it is one reason so little original leather has survived.  I don't like adding that acid to leather.  I hear folks say you don't use vinegaroon until it is neutralized, but how are folks measuring that?  I want the bags and leather products I am making to last as long as possible and function.  For me, that means using modern high quality dyes.  Safe and repeatable.  Just my two cents worth.   

As an aside, what was this charcoal-blue bag below dyed with?   

Marc

[Notchy Bob]

To all who responded, I extend my gratitude.  I also received a couple of notes by private message which were very illuminating and helpful.  Again, thank you to all who contributed.   I feel much better informed now.

I haven't checked my "brew" in a couple of days, but will continue to experiment with it.

Regarding oils and dressings, I generally use pure neatsfoot oil on leather, although I just discovered I am totally out of it.  I'm planning to order some more from Weaver Leather Supply, along with a few other odds and ends.  I see that mink oil was recommended, and I found that Weaver's has Fiebings and "Bee Natural" brand mink oils.  I checked the data sheets, and it appears that "Bee Natural," despite the name, is around 85% petroleum distillates with about 2.5% beeswax.  The Fiebing's Mink Oil data sheet was not so specific with regard to ingredients, but appears to also be made of primarily petroleum distillates.  Is there a brand of natural mink oil you guys prefer, or do you use the type with the petroleum base?

Weaver's data sheet for their Shep's 100% Pure Neatsfoot Oil indicates the product really is as labeled.  I will order some, as neatsfoot has always served me well in the past, but I guess I'll need to look elsewhere for Mink Oil.  Suggestions are welcome!

Thank you!

Notchy Bob

[thecapgunkid]

You have a lot of good advice here, especially Mark Elliots summary.  I've always used fine steel wool and white vinegar and have found that the longer it sits the darker the finish.
Pack the steel wool into a mayonaisse jar that has been thoroughly cleaned out and keep pouring until it almost overflows.  Set it aside by Halloween and wait for the superbowl.  Pour out the spirits into a glass jar, dump the steel wool and get the stuff back into a sealed jar.  The level of black you get will depend on the leather you use it on and the grease/oil yoou put on to refresh the leather.

That's for both the shoes and gunleather I make out of cowhide.  My old master told me that it is reacting with leather the way iron nails do, leaving little black rings where they hold the uppers until stitching replaces the nails.

It won't always react well with the leather that is not veg tanned.

Just go and do it, because it is so simple.

[Marcruger]

I use the 100% neatsfoot oil from Fiebing's.  It works great.  I use a little on a paper towel to rub in thin coats at a time.  I stop when it doesn't soak in within 3 seconds.  Beware of using too much, as it will kill the body of the leather and turn it black and soggy. 

You can get 100% mink oil from track of the wolf.  I would not use that for adding back in the natural oils to leather.  In my experience plain mink oil can remain tacky. 

Some companies make waterproofing for books that incorporate mink oil, beeswax and hardeners to produce a flexible and waterproof finish.  The hardener stops the tacky/sticky problem. 

God Bless, and best wishes,  Marc

[Mad Monk]

With vinegar.  Generally cider vinegar is about 4% acetic acid.  When you go to a wine vinegar the acetic acid content should be around 8%.  So in theory the sour wine vinegar should pick up a lot more iron.

[James Rogers]

I've always used cider vinegar as the white makes me want to hurl. I also use machining swarf, old nails, etc. in lieu of steel wool.

[EricEwing]

Nothing much to add on my part but I’ve kept a couple iron railroad spikes in a large mason jar with apple cider vinegar. It’s at least 7 years old now and I just add new vinegar whenever I want and give it about a week and then results are typically the same.

I always wondered about the combination having a negative long term effect on the leather but with some bags approaching 8-9 years of age I haven’t seen any issues yet.

[LRB]

  Bob, the type of vinegar is not critical. White or cider is fine. Small pieces of iron/steel are best. old rusty barbed wire is great. The metal must be free of any oil. Mayonnaise jar with plastic lid is good. To get a good solution, 3/4 weeks. Leave the lid just loose enough let the fumes escape.

[Notchy Bob]

Thank you very much, to all who contributed.  My batch of vinegaroon is exactly two weeks old today (8 October).  I checked it again yesterday afternoon, and found it had a "head" of light brown foam, and the level of fluid had risen enough to overflow the jar slightly.  Fortunately, I had elected to place the Mason jar on an inverted plastic lid, which was just sufficient to catch the spillover and avoid staining some brand-new shelving.

Lessons learned:  Leave more headspace, leave the lid a bit loose, and place the jar on a fluid-proof spill tray.

LRB's comments are much appreciated.  I did in fact load the jar with short bits of rusty fence wire and fence staples, as well as old nails.  I figured lots of small bits would present more total surface area for oxidation than larger chunks of iron, and this brew does appear to be progressing pretty quickly.  I had read something years ago, I think by the late Chuck Burrows, about de-greasing the metal with acetone first, so that's what I did.

I believe I'll try this out on one or two smaller projects before committing larger pieces of leather to the vinegaroon.  I'll give it another week, strain the fluid through cheesecloth, and then test it out.

Thank you, one and all. 

Best regards,

Notchy Bob

[Greg Pennell]

Don't overlook vinegaroon (iron acetate) as a stain for curly maple...just apply, let dry, and rub in some oil...no heating required.  Here's a curly maple dulcimer I stained with vinegaroon, as I was afraid using heat might loosen the glue joints.  Oh, and it turns walnut REALLY dark...like 200 year old Tennessee rifle dark...

Greg

[AZshot]

This is a fascinating history of a process I never knew! All I know is there is an insect related to a scorpion around here called a "Vinegaroon."   I may look into this type of stain for wood...I don't do much leather.

[Poor Bull]

I have used vinegaroon for years.  It doesn't take rocket science to make and produces a great black leather.
No secret formula and is simpler to deal with than some folks suggest.