Mineral oil bad for leather? Or good? Or neutral?

[fredk]

[1985]

I have several leather strops, some different leather than one another, they pick up dirt over the years, every few years I give them a good saddle soap with water, but only on the smooth face not the back.then I dab off access water, I place lint free cotton sheet or like pillow case on top then roller over pressing hard, to take up extra water,

if some get to much of a shine from where the razor just slides I will give a light pommy stone but not on the decor,, before washing process explain above,

Then I add Neatsfoot oil only to the backs of the strops and leave for a few days hanging up. Neatsfoot oil is not made the same way anymore like the old days.

Once I am happy with the moisture content left on the strops , I mix my home made purified fat from (cod line) all the crap gets separated by boiling it a few times, leave to cool then pick up the solid block of fat left on top of water. I then mix it with a touch of organic coco butter and a touch of lanolin, Warm up until tepid and rub mixture into the face on the leather and push a glass jar up and down the strop,

Then leave over night wrapped in cling film, then next day I rub off any thing that has not been absorbed in.leave again a few days hanging in the kitchen, then I rub the palm up and down until palm gets hot , Ill do the palm rub every day on each for a week, and that`s that ,and every time I use them I give them a rub with the palm,

No fungi no bad smells and Iv had some strops few several years,some are vintage I suspect, My belief  is Never leave leather to completely dry out for to many years it will rot,

All my strops hang in the kitchen round the side where moisture and heat gets to them but the cooking stuff don`t reach them so easy , they are also in line with door way so plenty of air, not much oil cooking in my place , Better to add something to leather rather than leave it drying out, in my opinion .

Edited January 17 by 1985

[SUP]

@1985That's great. You've found a technique that you like, to care for your leather strops. Perhaps you could explain that in a different thread so that others interested in the same could learn from your experience.

On 1/17/2024 at 4:56 PM, 1985 said:

a touch of organic coco butter

Cocoa butter is always organic, isn't it?  It cannot help itself.

On 1/17/2024 at 4:56 PM, 1985 said:

Never leave leather to completely dry out for to many years it will rot,

Absolutely. I completely agree. However, this thread is to learn about the effects of different oils on leathers. One of the things I am watching for, is to see how long the leathers can go before needing to be oiled, and if I delay, how long before damage becomes evident.

Hopefully, we will learn something.

[1985]

I get what your saying ,thinking this will be a very hard experiment to work out, given the type of leathers and treatments they have under gone , time factors. A lot of factors come into play, what animal the skin came from, how was the leather treated in the process with what chemicals, who had the leather after and what products did they use on it,

I don`t know if you are using already used products or stuff straight from manufacturer .

If I personally was to do this experiment, I would get all types of treated leather and some  plain as less messed about with , you can get off cuts from the manufacturers using different types of animals skins as this may play as a factor ,

place them in a drying area until you are satisfied with the dried out effects your wanting , bend the leather to see the flexibility and pull on and twist them , use different oils in different areas on that leather, place back in the drying area or radiator and just keep repeating the process,bending twisting and pulling eventually you will start to see weaknesses in the leather, all your be doing is speeding up the processes to know the outcomes,of the oils but won`t tell you how long they take to naturally dry out, But if one oil still shows flexibility in the leather than another on the same piece then there is some thing to note down,

As you know leather can last for decades If you are to use a product and not try to keep drying it out fast ,you may end up still studying the effects 10 years on,loll if you don`t force the effects

As I mainly work on leather strops for my self vintage ones Iv bought and others iv made from new leather I can tell you iv had many vintage from around the same era going back decades , some have torn like cardboard others seemed  a few years old, my only issue was,  I never new what the previous owners had been using over the years, to cause them to have completely different effects.

May be your best to get hold of the manufacturers who treat the skins as they would have the knowledge also museums they are very knowledgeable on treatments as they have to preserve many items involving leather, they will know what not to use on leather that may speed up the rotting process and how often they need to do it.

And of cause the old boys and girls who have worked mending thousands of specialized leather items like vintage suit cases or brief cases, saddlers who are top of there game working with horse equipment ,, they would have so much knowledge, if none reply here then go visiting the old stores that may be around,find out with the manufactures why they produce certain oil for leather and whats in it ask for dater sheets,

There must also be old books that have explanations on studies to do with effects with oils on leather but remember the oils back then in the early 18th and 19th centuries were produced different from to days, most likely used fats,

But I gather your possibly looking at modern leathers with modern oils to see what will be destructive to leather, i just think to many factors will play its part in this as mentioned above , I also think to much of a treatment of oil can weaken as well , theirs a fine line to caring and destroying,hopefully gathering information from  experts in there field may steer you right,.

This is going to lead you down the rabbit hole with many tunnels , good luck` who knows you may come to some conclusions that you can share with evidence to show.

[SUP]

@1985 Our experiment is for the ordinary person who wonders what to use, not something I plan to publish in a journal. I am  pretty familiar with how to conduct scientific experiments - having a background in research, among other things.

Scientific experiments, if done truly scientifically, select very narrow aims or become too generalized to reach true scientific conclusions. But then, half the time, so called 'scientific conclusions' have such narrow limits that they are not of much use to the layman. The entire process, if I want to go down that path,  will be much more complicated than what you are describing. It also cannot be done by one person or even 2 or 3 people; it will require a team of people over decades. Otherwise it would be pointless. Unless I want  a good part of it to be theory - information from people - which is so much all word-of-mouth - "I heard from this old saddler" and, "My grandfather used this" and so on. Nothing wrong with that, but is that the only thing? That is, in fact, what I am questioning and the reason why we are doing this informal experiment.

For me, the question started with wondering why people said mineral oil, indeed any petroleum products, are bad for leather, while at the same time, in ignorance, praising several products which are full of them. I decided to check if it is true and we just added a few more oils for comparison and as a matter of further curiosity.

@fredk, @chuck123wapati and I are testing several oils on veg-tanned leathers.

One of these days, I plan to expand to other leathers as well.

But this is a fun, informal experiment. 

I, for one, am not interested in setting this up as a formal experiment, contacting tanneries and so on. 

You have evidently given this a lot of thought. If you want to set up a more scientific experiment, go right ahead.

It will be interesting to learn more about it.

 

Edited February 2 by SUP

[1985]

This is not meant to sound cocky in anyway but no, not much thought given written to what I write down just came naturally the way I think` although it may come across this way to some. I have a some autistic ways to the way I think  written diarrhea is one of them. 

But then if you were going to announce the out come in your findings after carrying on with the tests in this forum ,won`t some people just be questioning your methods of practice to whether it was worth it,after all they only going by your word of mouth,

Would this not be just like every one else giving there experience in the use of products used on leather` whether its true or not what the out come was ,this would surely bring us back to just another persons views as no scientific documentation to show us proof, even though I am not a great believer on scientific proof most of the time.were told what they want us to believe.

I for one applaud any person trying out different methods does not need scientific evidence to get results as science has been proven to be wrong many times in the passed,and fudge the truth, specially when they don`t announce the correct findings as many companies have pay scientist researchers to only show the good stuff on paper with there product and not put down the bad stuff in a product on there findings ,just so companies make silly amount of money selling the product by the time they get found out , so they can`t even be trusted a lot of the time, 

This is why I stated people who have years of experience working with leather every day would know the out come with oil products,but if you choose to not believe in them and do your own research for fun then good on ya why not ,its the only real findings some times,

I used to work in a museum helping the curator, documenting items , I seen stuff they would borrow and lend out many pieces to other museums, and listen to some of the ways and methods items had to be treated ,there were volunteers who worked with us very knowledgeable people and very experienced in there field.who I would trust there knowledge,after asking a thousand and one questions I was satisfied with there answers.

off subject for a minute but has some meaning , One bloke who come to work with us worked in a nuclear plant for 20 years the knowledge he told me on nuclear waste and radiation was fascinating. word of mouth is not always bad to take on board, theirs some truths in it.

The only trouble with products to day , the companies are changing there make up so quick to keep up with the competition by using cheaper man made substances in there products to keep costs down and profits up. so buy the time we get used to something they no longer produce it in the same way, that`s why using a product years ago possibly was really great but as the product changes the older generation may not notice anything much difference, So when some one uses the product for the first time many years down the line and does not recommend it that`s because its changed, this is why there is so much controversy on peoples opinions,some are right some don`t know any different.

Anyway ill be interested in your findings if your decide to place them on this thread be interesting to find out what you discovered with the oils of today

 

 

 

 

[SUP]

Frankly, @1985, I don't give a hoot about people questioning me or saying anything at all about what I am doing. I just answer them as I am answering you and have answered others in the past. At least I am questioning and not just blindly accepting what people have said over 100s of years. The world has come a long way in those 100s of years - I like to be open to new ideas, try them and if they don't work? Fine. If they do, something new learnt. Beyond that, I'm doing this for me and anyone else who is interested.

 

Edited February 2 by SUP

[dikman]

Sup, by starting this thread (and the ensuing discussion from others) you have made me re-think my attitude towards using mineral oil on leather - I'm referring to the pharmaceutical/medicinal grade/baby oil of course. Up until now I've been fixated on only using natural products on leather but this thread has given me cause to have a re-think.

You've done well.

[fredk]

4- monthly & 5-weekly report since last

#1; Baby Oil;  Flex is good, better than Control #2,  Smell = mildly 'leather',  Other (fungus, deterioration ) = 0

#2;  Cooking Oil (rape seed); Flex is very very good, very much better than Control #2,   Smell = very slightly 'leather',   Other = 0

#3;  Lard (pork fats); Flex is slightly better than Control #2,  Smell = very slightly 'leather' and a hint of oil,  Other = surface feels a bit 'greasy'

#4; NFO Compound; Flex is very good, better than Control #2,  Smell = neutral, Other = 0

#5; Olive Oil;  Flex is better than Control #2,  Smell = very slightly 'leather' with a hint of oil,  Other = 0

#6; 3-in-1 Oil;  Flex is stiffer than Control #2.  Smell = strongly of 3-in-1 oil,  Other = 0

#7; Vaseline;  Flex is stiffer than Control #2,  Smell = faintly of 'leather'   Other; Surface feels very greasy

#8;  Control #1; kept with #1 to #7; Flex has stiffened

#9; Control #2; kept inside away from influences

No change in colour in any of the pieces

Thats all for now

 

 

 

 

 

Edited February 7 by fredk

[SUP]

@fredk I've been a bit lax, I'm afraid. You have added a lot of information here.

I need to pull up my socks and get to work! 

Since the cold days are gone, I will check what effect the cold and humidity here have had on the leathers and update in the next few days.

 

@dikman Thank you. 

 

 

[fredk]

I'll be doing my next proper check this coming weekend

[SUP]

@fredk, I'm afraid I'm going to be later than that.

I'm going to Jim Linnell's classes! 2 of them over the week-end - Friday - to refine swivel knife techniques and Saturday to learn how to make leather jewelry - specifically how to make stones like Turquoise realistically. On Sunday he is teaching figure carving.  I might not be able to go for it. But 2 classes itself will be a great learning experience.

 

Edited February 28 by SUP

[fredk]

I forgot to do an update

The test pieces in the car - no change

At the start of this month I made up a second batch of 8 pieces and hung them up on a specially made rail. They'll get full sun on them as well as wind and rain. I'll check them tomorrow

[SUP]

 I've been lax. I need to pull up my socks and get to work. I will do a detailed update next week. 

Had a sudden cold  and rainy spell but warmer now, so it is time to see how winter affected the leather outside.

 

 

[SUP]

Report for 22nd March, 2024.

The leather pieces showed some differences from 3 months ago.

Firstly, an explanation of what the descriptions mean.

Smoothness indicates the surface feel – silky smooth or rough.

Shape indicates how the pieces hold their shape – whether the corners curl or the edges curve or even curve in a wavy manner.

Stiffness indicates how easy it is to bend or fold the leather.

Color: Indicates the extent of darkening.

Smoothness: The leather pieces treated with Mineral oil were all the smoothest, having a silky feel. The next were the leather pieces treated with Neatsfoot oil and Coconut oil, which were similar - relatively silky. The Mink oil treated leather pieces felt a little rough, even more so than the control pieces.

Color: Coconut oil darkened all the pieces the most, although all the pieces in all the locations except directly outside, are lighter now, than 3 months ago. in fact, they are almost as light as the leathers treated with the other oils. The least darkened are the leathers treated with Mink oil. Pieces treated with Mineral oil all have remarkably similar color except for the one outside. They also have remarkably uniform color - actually beautiful.

Shape: The most warping was seen in the control leather pieces at every location.  The Mink oil treated leathers were also relatively warped, the Coconut oil treated ones, less so. The leather pieces treated with Mineral oil were the least warped and held their flat shapes very well.

Stiffness: Here, the stiffness differed more according to location. The leathers kept outside were the stiffest in their treatment categories. The least stiff were the ones treated with Coconut oil and then the ones with Neatsfoot oil. Most stiff were the leathers treated with Mineral oil. The leathers treated with Coconut oil are actually very soft.

All the pieces treated with Coconut oil are the softest and smoothness is second only to Mineral oil treated leathers. This is surprising as, initially they had appeared a bit dry in Dec., 2023. They darkened earlier but over time, all except the leather placed outside are close in color to the leather pieces treated with the other oils.

The leather pieces treated with Mineral oil are the flattest with least warping, the smoothest and all darkened uniformly and to the same extent in all locations except outside where the piece darkened significantly more, as expected.  The darkening is also remarkably uniform over each piece.  They are all however, also the stiffest.in their location categories.

The leather pieces treated with Neatsfoot oil are moderate in every way. Moderately smooth, moderately stiff,  moderately dark and moderately but not too warped.

Mink oil continues to surprise me. The leather pieces in all locations feel least smooth, in fact a little rough. In all the locations- they feel like the controls – untreated. They are the most stiff and dry across all locations, including inside. They are however, the least darkened.

Smell: they all smell like leather to me. There is no mold on any of the pieces.

Seeing the results at this 6 month point (more or less), I can see why more than one ingredient is used to condition leather. Depending on the use of the leather goods, specific ingredients that complement each other can be selected to get the best results. This is still premature and I have added tallow, cod liver oil  and lanolin to the line-up. I just added them a couple of days ago, so have not included them here. I will list them separately next week and from next time, list them all together, along with any other ingredient that I might add.

If colors in the photograph appear different from my description, it could be the play of light.

 

Edited March 22 by SUP

[SUP]

CORRECTION: Leather pieces treated with Mink oil are not the stiffest. They are second to the pieces treated with Mineral oil.

[GeKl]

Interesting experiment! I ended up here when Googling for more information about whether or not vaseline would be bad as a component of a specific leather balm I had my eye on (Urban Forest Premium Leather Balsam, which I wanted to get as alternative to Obenauf Heavy Duty LP which isn't available here). I had already looked for what were 'good' products vs 'bad', with anything petroleum based (including vaseline) most often being chucked into the 'bad' pile. But that balm also has beeswax, avocado oil and other natural oils in it, besides vaseline. Reviews on it are excellent, as is 'picture proof', but still I was concerned.
 
While not conclusive/100% scientific yet, the rational debate and testing in this thread has at least given me a bit more peace of mind about potentially using that product; since it's not pure vaseline and contains natural oils and beeswax as well, there's a good chance it's a 'healthy' balance between them all and it might not long term deteriorate the leather (at least that's what I'm telling myself, since I couldn't find another product here that guaranteed only mixes only natural oils and beeswax, and making my own is not an option). It's also not like I'm planning to treat heirloom pieces with it, just some knife sheaths and revive/condition a few leather belt satchels. But when there's doubt, my mind tends to go down rabbit holes.

So thanks for your efforts, adding actual valuable info to the interwebs rather than just echoing/parroting (unfounded) hearsay.

Edited April 5 by GeKl

[fredk]

I'm due to make a report but in the interim my test pieces with vaseline are still slick with it on the surface. I would say it would make a good water repellent top finish

[GeKl]

For my use case, it's partially about water proofing knife sheaths, but also about conditioning/nourishing the leather, as some sheaths and pouches are a bit dry. But given that the product I'm looking at seems like a soft wax/oil mix, I think/hope it might have enough conditioning potential to not have to bother with really liquid oils first. I'd like to avoid having to get multiple products. Not sure if linking is allowed/frowned upon, so just sharing a picture of how it looks, makes me think it's the typical soft waxy conditioner that could even be applied without adding heat:
 
("Avocado and other high quality plant based oils, high quality vaseline, natural beeswax, subtle fragrance")

[SUP]

@GeKl, Thank you. 

I am, in fact, in the process of making a set with mineral oil + a very small quantity of coconut oil - I am using 10% - hopefully that will decrease the stiffness that mineral oil allows. 

@fredk waterproofing with Vaseline is a good idea - a small quantity should work, or maybe mixed with beeswax. 

@GeKl, I think I was typing as your response got posted. That product has oils as well as beeswax and Vaseline. Seeing how ubiquitous such ingredients are in almost every product, I wonder whether they are the ones mainly dong all the work and the plant based oils are added to satisfy customers who still have an issue with petroleum based ingredients. The plant-based ingredients seem to change in different products but the petroleum based ones are more or less the same ones.

Edited April 5 by SUP

[dikman]

SUP, I suspect you're right, the common denominator I found, when looking at the MSDS for various leather treatments, is mineral oil. It generally forms the major component in order to make the beeswax soft enough to spread as a paste. Most of the other additives are in quite small quantities, perhaps to add a pleasant smell and make people feel good because it has "natural ingredients" - although many companies consider mineral oil to be a natural product for the purpose of advertising.

Plus it's probably relatively cheap to use as a commercial component.

[SUP]

@dikman yes and along with mineral oil, other petroleum based products appear as additional ingredients as well.

About mineral oils, it is purely organic (versus inorganic) from the point of view of Chemistry. I think of it as  natural as well - the result of refining of crude oil - sources of fossil fuels. I suspect people think it is not organic because of the name - they associate the term 'mineral' with, I suppose metals and nonmetals, essentially inorganic material.  I wonder if there is another name for mineral oil.

 

 

 

[SUP]

Here are the pics and information about Lanolin, Tallow and cod liver oil. - the first row is treated with lanolin, the 2nd, with tallow and third with cod liver oil. The piece on the extreme left is untreated, for comparison.

Lanolin, tallow, cod liver oil - applied to 4 pieces each, one piece being placed in garage, outside, car and control area.

Observations as follows:

Lanolin: Immediately on application, leather pieces slightly darker than control – all remarkably consistently darkened. Smoother as well. Mild smell of lanolin.

Tallow: Immediately on application, leather pieces slightly darker than control. Smooth. No smell of tallow.

Cod liver oil: Immediately on application, leather pieces slightly darker than control. Smooth. Smell of cod liver oil.

All pieces have darkened slightly after application of test material – more or less to a similar extent. The lanolin gave the most consistent immediate darkening with the least streaking or spots. The pieces treated with tallow have no smell while those treated with lanolin and cod liver oil smell of those respective products. All the pieces feel smooth - smoother than the control. They are as soft as well but not softer than the control.

I completed this a while ago; now preparing the set with the mix of mineral oil and coconut oil.

[fredk]

Good

I'll try to get a check on my pieces tomorrow

[SUP]

I am thinking of a way to include petroleum jelly ever since your experience that it might be giving a water repellent effect.. That will be a different experiment, more to check how long the water repellent effect remains when out in the rain - its been raining here quite a bit - and then, when kept in different places, how long the effect remains. Have you had any experience with this?