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

[SUP]

@chuck123wapati, the article you have given shows the effects of fats soon after tanning, not the effects of long-term use of it by the users of that leather. The article also talks about how synthetic oils have superseded natural ones because of oxidative issues. But it does not say exactly which fats and oils and what the effects are over a long time, Although it does say the actual type oil does not matter. It matters to us though.

All of us here are talking from personal experience or trying to get personal experience  and are curious to  know, once and for all,  about the true ill-effects or advantages, or both, of oils commonly used by ordinary leatherworkers. If you do have actual knowledge it would be nice to hear about it, like so many others have so beautifully and positively contributed to this thread.

Edited September 20, 2023 by SUP
Language corrections.

[SUP]

@fredk I bought most of my thread based on diameter and color and do not know what it is made of - probably synthetic, since that is what is mainly available everywhere these days. I took off all the labels as well unfortunately. So I will need to look for cotton or linen. I don't mind though,. It will be an interesting exercise. 

If your synthetic thread was strong and stable so many years later, that is evidently not the problem. I have not heard about anyone else complaining of synthetic fibres breaking down either.

So that narrows it down to the leather itself and natural fibres.

Your experience with linen thread, so similar to mine, suggests it is the thread itself which deteriorates over time, naturally, rather than because of anything applied to it. I wonder why not all leather goods made with natural fibres  deteriorate though. Well waxed and therefore protected maybe?  Or maybe the stitching itself is the issue too? Too tight, too loose, I'm afraid I cannot help there. Does anyone have any idea about this?

Edited September 20, 2023 by SUP

[TomE]

1 hour ago, chuck123wapati said:

To think the effects of various oils on leather has never been considered is silly, its been studied for centuries,  you just have to look for the research its a multi billion dollar industry. Here is one i found in about ten minutes. I will add you will have to find old studies for reliable information, any new info will be tainted by the climate change agenda so I'm sure fossil fuel derived oils will not be on the top ten list in any new publication.

https://www.researchgate.net/publication/339328369_Leather_and_Textile_Uses_of_Fats_and_Oils

I have more but my links were dropped when i re-set my box. 

Thanks for the article, @chuck123wapati.  Lots of good information about the chemistry of tanning and currying leather.  I understand @SUP's point about the difference between producing leather and maintaining it with a conditioner, but I find it helpful to know what the starting point is at the tannery.

Wish we had a reference section of this forum for depositing and downloading useful articles, book chapters, etc.  I maintain my own collection but it is obviously not all-inclusive and it's fun to see what others turn up.  

 

6 minutes ago, SUP said:

@fredk I bought most of my thread based on diameter and color and do not know what it is made of - probably synthetic, since that is what is mainly available everywhere these days. I took off all the labels as well unfortunately. So I will need to look for cotton or linen. I don't mind though,. It will be an interesting exercise. 

If your synthetic thread was strong and stable so many years later, that is evidently not the problem. I have not heard about anyone else complaining of synthetic fibres breaking down either.

So that narrows it down to the leather itself and natural fibres.

Your experience with linen thread, so similar to mine, suggests it is the thread itself which deteriorates over time, naturally, rather than because of anything applied to it. I wonder why not all leather goods made with natural fibres  deteriorate though. Well waxed and therefore protected maybe?  Or maybe the stitching itself is the issue too? Too tight, too loose, I'm afraid I cannot help there. Does anyone have any idea about this?

 Linen thread most certainly can rot.  When repairing tack, I see linen thread that has deteriorated after decades of use.  I don't know if it's caused by mold, a chemical used to maintain the tack, or something else.  Coating linen thread with beeswax is supposed to help protect it, but for how long?  There was a recent post asking where to find linen thread and the OP noted that Barbour has gone out of business.  Campbell-Randall Corp. has a limited selection of Barbour thread.  For hand sewing tack I mostly use bonded nylon thread from my machine, and for heavier weights I use waxed polyester thread from Maine Thread Co.

[chuck123wapati]

4 minutes ago, TomE said:

Thanks for the article, @chuck123wapati.  Lots of good information about the chemistry of tanning and currying leather.  I understand @SUP's point about the difference between producing leather and maintaining it with a conditioner, but I find it helpful to know what the starting point is at the tannery.

Wish we had a reference section of this forum for depositing and downloading useful articles, book chapters, etc.  I maintain my own collection but it is obviously not all-inclusive and it's fun to see what others turn up.  

 

 Linen thread most certainly can rot.  When repairing tack, I see linen thread that has deteriorated after decades of use.  I don't know if it's caused by mold, a chemical used to maintain the tack, or something else.  Coating linen thread with beeswax is supposed to help protect it, but for how long?  There was a recent post asking where to find linen thread and the OP noted that Barbour has gone out of business.  Campbell-Randall Corp. has a limited selection of Barbour thread.  For hand sewing tack I mostly use bonded nylon thread from my machine, and for heavier weights I use waxed polyester thread from Maine Thread Co.

veg tanned leather has no oils applied after tanning that is what we do its called liquoring and it is the starting point of re adding oils to the veg tanned leather.

 

27 minutes ago, SUP said:

@chuck123wapati, the article you have given shows the effects of fats soon after tanning, not the effects of long-term use of it by the users of that leather. The article also talks about how synthetic oils have superseded natural ones because of oxidative issues. But it does not say exactly which fats and oils and what the effects are over a long time, Although it does say the actual type oil does not matter. It matters to us though.

All of us here are talking from personal experience or trying to get personal experience  and are curious to  know, once and for all,  about the true ill-effects or advantages, or both, of oils commonly used by ordinary leatherworkers. If you do have actual knowledge it would be nice to hear about it, like so many others have so beautifully and positively contributed to this thread.

 What you may not realize is that liquoring is what we do when we apply oils on veg tan, until we do that no oils have been applied after tanning that is what we do and it is the long term. 

[SUP]

@TomE It is clear that synthetic fibres survive well over time. Thank you, each person's information adds to confirming this.

And having a reference section is such a good idea!

We have a proverb in Hindi which says, roughly as follows: "What can be done tomorrow can be done today; what can be done today can be done now"

Going by this, maybe those  of us who find good articles can contribute and  request the forum to make it available to everyone. We can start with yours, @chuck123wapati, if you do not mind. 

Now how does one go about requesting the forum to have a section for a repository of such knowledge or is there one already to which a section can be added? 

 

 

[SUP]

 

3 minutes ago, chuck123wapati said:

 What you may not realize is that liquoring is what we do when we apply oils on veg tan, until we do that no oils have been applied after tanning that is what we do and it is the long term

@chuck123wapati I certainly I did not know that, as many others probably do not either. All the more reason for a repository of knowledge. Besides, I am a little surprised at the general description of the oils. Usually in experiments, it is very specific and even if the results say the same, the actual items used are listed. It probably is, in the full article. 

[chuck123wapati]

24 minutes ago, SUP said:

@fredk I bought most of my thread based on diameter and color and do not know what it is made of - probably synthetic, since that is what is mainly available everywhere these days. I took off all the labels as well unfortunately. So I will need to look for cotton or linen. I don't mind though,. It will be an interesting exercise. 

If your synthetic thread was strong and stable so many years later, that is evidently not the problem. I have not heard about anyone else complaining of synthetic fibres breaking down either.

So that narrows it down to the leather itself and natural fibres.

Your experience with linen thread, so similar to mine, suggests it is the thread itself which deteriorates over time, naturally, rather than because of anything applied to it. I wonder why not all leather goods made with natural fibres  deteriorate though. Well waxed and therefore protected maybe?  Or maybe the stitching itself is the issue too? Too tight, too loose, I'm afraid I cannot help there. Does anyone have any idea about this?

my actual knowledge of oils comes from years of work not only on leather but construction, automotive, and various types of maintenance. I'll give an example i used to work in a prison, Many chemicals were not allowed for obvious reasons. Lubricating oils being one of them. the food service manager could not get oils needed to lubricate his meat slicers so he instructed his inmates to use vegetable oil for lubrication. In less than a month the veg oil had dried into a literal gum that could not be removed by any ordinary means of cleaning, it had to be soaked for hours in our garage in the parts washer. Not only that it was rancid as well soooooo........ its not for leather either it will dry out and stink,its for cooking only and only if you have decent health care coverage.

neets foot oil comes from cows put it back in and you wont have a problem.

[chuck123wapati]

9 minutes ago, SUP said:

@TomE It is clear that synthetic fibres survive well over time. Thank you, each person's information adds to confirming this.

And having a reference section is such a good idea!

We have a proverb in Hindi which says, roughly as follows: "What can be done tomorrow can be done today; what can be done today can be done now"

Going by this, maybe those  of us who find good articles can contribute and  request the forum to make it available to everyone. We can start with yours, @chuck123wapati, if you do not mind. 

Now how does one go about requesting the forum to have a section for a repository of such knowledge or is there one already to which a section can be added? 

 

 

i would love that!!! 

[TomE]

While we're on the subject of fats and oils...

Newbury - 1940 - Oils, fats and waxes in the leather industry.pdf

Blockey - The Application of Oils and Greases to Leather.pdf

 

Edited September 20, 2023 by Northmount
Added appication of ... that was on drop box

[chuck123wapati]

My dogs collars are still soft and flexible after three years of being dogs outside playing in the water, rain and dirt the only additional oils they have received since I made them are from the dogs themselves and the threads haven't rotted either. lol  So my deductive reasoning kicks in and says animal oils would probably be best for conditioning animal hides. Any one ever have a dog collar that needed re conditioned?