Oils In Leather (Chemistry)

[spectre6000]

No problem at all! It's been a fun and rewarding project. I'm glad to know others are benefiting as well.

[pennyjf]

I am also very interested.  I have had requests for patent finish on some of my leather work projects (braided horse tack)

Thank you for posting all this.  Hope you are recovered from your car accident sounds scary!

[Martyn]

This is a fascinating thread - it'd be great if you could sort the pictures out?

The forum software is rendering an image as it should and google is serving an image, but that image is a white block with a greyed out stop sign, which would generally mean it's either a blocked image or a link to a non-existent or moved image. Even when viewed as an external link it's still blocked/stopped/broken...

https://lh3.googleusercontent.com/i_Q90a27xCZOHC8WLZ5NIkecjDYk3vLn2_xbVBFsO4wVdzRQBrlraWrlmy7JlhwoEcpBWFUqMa-_0u0PRJrVDdQ-UKkijoqkwWfrhmiunWfMNn01fbHYyE_zAbSp850_dcIyJaMYHCrFbPwdYdb9cp6nmeQyjX6XYnZlsctIPUMxMd-UBT02Uf9JVm2IZycEBp3KP8MciuVyZKQcRP_ii88V6eCNS-k0gHOgeXA8C9AcV6iTxMGEhxXGiTIELMDvuUCxprXDlondAgbBdwoQr4a_RWguh1qPrp18tqQY-bqeg6pVyJ7yCcWMkcQgiMkWRdnYBWeKWC59CDucB-tMxCR3us_POx3HFUnxA1e6t_1-d2dT2erZvcBsKUYisA2Mwla5lrCLABPPfCGrjsh9a5NGHpLos9ddWV45V3MyVnBWVSQT1jAkCH4-QvB6tktbDPs2YgdqlDMtzYCNw98nNSHn0OJiXFbuCY-46Hcia7HWxERlCm-ysxxVJEKfVz9uid2ljUjXpNY1Sd4wumbhPOCcX2GHgcRFD5G9jFPpJSHFhCydA0Mz6T5Joe8tbUCVjUS_=w640-h480-no

...which means the problem is with your image hosting, not the forum software.

If you look at the very end of the link above, it defines display parameters...

=w640-h480-no

...the '-no' at the end suggests a permissions issue perhaps?

Edited June 14, 2016 by Martyn

[spectre6000]

I picked a photo at random, and it appears to be working across devices for me regardless of any session states. Can someone please do a sanity check and confirm whether on not it's visible to anyone else? 

Martyn, I'm not familiar with a white square and grayed out stop sign logo. Could you please share your browsing info (OS, application, version, etc.)?

Edited June 14, 2016 by spectre6000

[Martyn]

Yes, that is displaying properly.

I'm using firefox on windows 7 home premium (links are broken in chrome too). If you are seeing images in your older posts, I think you asre seeing cached images. Clear your browser cache and it's my bet you will see the stop sign.

Interestingly your non-displaying image links terminate with...

=w640-h480-no

while the one that displays terminates with...

=w640-h480-no&key=802effcce77dc2b3bb281b234fe1f57339fd2766e2d901edb31d8d7f77113528

 

Edited June 14, 2016 by Martyn

[spectre6000]

On 4/3/2016 at 5:25 PM, spectre6000 said:

Sorry for the extended silent period. Life got busy, then I got in a pretty horrific car accident. I'm finally back to where I can get back in the shop a bit, so back to this project!

Am I correct that there have been some changes while I was away? Signing in with Facebook, and... attach images via URL?

Since we're posting photos and to get everything in the same place, here's the beeswax rendering photos:

There was more rendering after this photo, but what I have.

Soooo.... I started by cutting some belly trimmings into rectangular pieces.

Tinker Tailor for the win! I fine tuned my iron to 145° with the IR gun, used a small anvil as a thermal battery, and parchment paper to avoid ruining the iron or the anvil. The target was between 145° and 155°, erring on the low side for safety. As previously stated, that narrow range is pretty much it where the wax will be liquid and the leather won't be ruined. 

I shaved the beeswax block so that I could weigh out the wax for melting.

And I weighed samples out for a total of 20 grams each (a little less than 3/4 ounce) between the wax and oil. I went with olive oil since it's the closest I have to neatsfoot (the status quo) by fatty acid content.

The five samples were neat beeswax, 75/25, 50/50, 25/50, and 15/85 beeswax to oil ratios. The partial sticky notes (somehow I only had one sticky note and the backing pad...) are marked 20, 15, 10, and 5, referring to the grams of beeswax with the unlabeled being 3. The balance was filled with olive oil to a total of 20 grams. Then...

A last minute sanity check, and...

Into the double boiler. This is the smaller of the two pots I bought for this experiment with an aluminum pie tin sliced to form a smaller diameter, perforated, and wrapped in foil so it would stay together under the weight of the glass sample vessels. I think they were glass tea light candle holders, and I got them at the same thrift store I got all the hardware for this experiment. I also found this:

February 1958 Brother portable sewing machine in pretty good, albeit neglected condition. I restored it for my wife for Xmas, and she loved it! Great little thrift store.

Anyway...

The bellies were pretty seriously old... So much so that I have no idea when I got them, from where, or why. They're all slightly different colors, and all pretty dry, so I taped them off to have a bit more control over the control. Then I got to business.

While the wax/oil mixtures were melting, I made go with the oils. The flax oil smells sweet, walnut smells earthy, canola doesn't have much in the way of a smell, and the olive oil smells spicy. I applied multiple coats until it took a little longer for the oil to all be absorbed, and heated the wax-based samples to temp prior to applying the wax oil mixture. This allowed the wax to absorb and not just harden at the surface on contact. I dipped the hot neat wax sample into the hot wax at one end just to see how stiff it got. 

Here's the end result for the day:

Left to right, top to bottom, that's canola oil, 25% wax, 100% wax, flax, 15% wax, 75% wax, walnut, olive, and 50% wax, and the loner is the control (the organization makes more sense if you rotate it to the right 90°, where you get the waxes in decreasing order followed by the oils with the control to the side). It should be noted that the leather was very dry, and the tape pulled some of the top grain off, lightening the appearance.

The higher wax concentration samples proved difficult to apply, and the result appears pretty splotchy. Application with a good aesthetic result would be either difficult or very time consuming and complicated without significant investment in equipment or risking ruining the leather via heat. Additionally, given the role of the oil in the leather, I don't think ultra high beeswax mixtures will allow the fatty acids to do their lubrication and migration song and dance. That said, it seems the heavier wax mixtures would have a fixative effect on any tooling, and this is desirable... On the other end of the spectrum, it's simply too soon to have any idea how the polymerization of the shorter fatty acid chains will affect the end result.

In terms of color, there are variations in the leather sample pieces muddying things up a bit, but all methods and materials darkened the leather considerably at this point with canola as the surprise stand out. I'm not sure why this is. On the neat wax sample, you can see a strip at the end where I heated it up and just dunked it into the hot wax. The heavy saturation reflects less light than the less saturated area. The splotchiness in the 75% wax sample is a prime example of the difficulty applying higher wax concentrations, while the lesser wax mixtures were considerably easier. Time will tell how these effects last over time.

In addition to the application experience, another significant subjective observation is the smell. The walnut oil sample smelled predominantly of walnut; earthy and not unpleasant, but not especially pleasant either. The olive oil sample smelled essentially like olive oil with no real leather aroma; a bit on the spicy side. The canola oil had no real smell at all. The waxed samples smell to varying degrees of sweet honey to spicy olive oil based on their respective concentrations without much leather smell. The flax oil is sweet on its own, and in the leather has a wonderful smell that stands out above the rest. The leather by itself didn't smell especially strong of anything (it's old), but the flax oil made for a very good leather smell beyond expectation. I don't know why this is, but based on reports of fish oils smelling especially like leather, it makes me wonder exactly what's going on there. They both are notoriously high in omega 3 fatty acids (mid-length polyunsaturated), so maybe there's something going on there... Who knows.

Finally, I allowed the wax mixtures to cool and harden. I expected the neat wax to harden like the rest of the wax, and that the lesser samples would soften considerably to the point that the 15% sample would barely be any more viscous than the oil, but surprisingly they all hardened save the 15% sample.

I stuck my finger in each one, and while the 25% sample gave a tiny bit where some bubbles had formed but was otherwise solid, only the 15% mixture really gave at all. Some water had splashed in from the boiling water, and it squished out from this sample as well. As an aside, it makes good lip balm. Some fiddling with other oils could make for a pretty awesome home made Burt's Bees replacement (the olive oil just lacks the good smell)! 

So... Where does that leave us? The 15%, 25%, and to a lesser extent 50% wax mixtures were easy enough to apply as to be viable. Heavier than that was too difficult using these methods. The liquid oils are obviously easy to apply, but time will tell how they do over time. I like the idea of the wax fixing tooling, but have some concern at what it will do over time as the oils break down and subsequently migrate... Or would the wax prevent migration? Additionally, wax is known to stiffen leather, but with enough oil it softens considerably... The question is how this affects things when it's suspended between the leather fibers. How does it affect things as the oil breaks down? The same question can be asked of the polymerization from the shorter fatty acid chains oxidizing. Does this form a barrier that makes subsequent applications of oil difficult or even impossible? The smooth surface that results from the polymer film would make for a good dark color, this would be even more the case when combined with a percentage of wax. The sweet smell of the wax combined with the sweet leather smell from the flax oil and the shine and tooling fixation could be awesome! It could also ultimately shorten the lifespan of the work... It would probably be years before the effects were noticeable, and they may not happen at all, but it is something outside the norm about which I can't find any information.

The next phase is to wait and see what happens over time... Months... Years... I'm not that patient for the immediate projects, so I'll have to decide on something sooner. The next thing I'd like to try is some lighter wax mixtures with other oils. The flax is especially interesting from the perspective of the eventual high gloss polymer finish and dark color it would ultimately result in, but I want to get some longer carbon chains in there too for a bit better lubricity over a longer period of time. That might ultimately mean a multi-phase finish. Maybe a light oiling or two front and back with olive oil, then finish with a heavy application of a 15-25% beeswax/flax oil mixture. That would help the tooling stay crisp, eventually result in a very polished finish, and the sweet smell of the wax and the sweet leather smell will likely be a pretty killer combo. I might investigate another oil or two in there for fun too when I go for the second round... We'll see.

Fingers crossed... Testing in other browsers now...

Tested. Working. Let me know if it plays nice over there... It's something like 1 in the morning over there now, so maybe I'll hear about it in the morning. 

Edited June 15, 2016 by spectre6000

[Martyn]

44 minutes ago, spectre6000 said:

Tested. Working. Let me know if it plays nice over there... It's something like 1 in the morning over there now, so maybe I'll hear about it in the morning. 

Looks good, good job. It's late here too (early?) so I'll read it tomorrow, the pictures make all the difference though.

[LH4H]

An absolutely fascinating read, thank you!  I've been dealing with a spew outbreak and found this discussion.

I know this is a bit much to ask but...it's been almost 8 years.....do you happen to have these samples still?  I'd be very curious to see what they look/smell like now!

[rustyred]

@spectre6000 I am also curious about results. Please give an update if you're around. For science!

[spectre6000]

Woof. Necro thread. I haven't been to this forum at all in nearly that entire time to boot. I got a notification email though, and my password still works, so cool! 

The good news, I suppose, is that you got my attention. More good news is that I might actually still have those samples kicking around. The bad news is that I moved since then, and the house I live in now is experiencing some extremely major repair issues. The box those samples would be in is DEEPLY buried in storage at the moment. 

I can say that the last time I saw them (more this side of the timeline than my last post), they had darkened up a bit with age with some of the lighter samples sort of evening out (the oiled section didn't get darker at the same rate maybe?), and there was no smell other than just leather. I don't recall any bloom whatsoever either. 

Here's the really good news though... I made up a large batch of the final oil/wax mixture, and it became my default finish treatment. The belt I wear every day gets a touch up once a year/when it occurs to me and I have the time (nowhere near once a year if I'm being honest). By the time I eventually used up the first jar I made, it smelled... compromised. Rancid probably isn't exactly the right word, but it was clear the fatty acids were breaking down and oxidizing. I still used it, and once applied, the smell went away. Never was an issue. The whole thing about those aromatic compounds is that they're volatile (which is why they get in the air to where you can smell them), and so they dissipate quickly and leave the good stuff behind.

I further went on to experiment with coloring the leather with UV using the oil/wax as a color enhancer. Most of my projects are a deep mahogany brown as a result of the two in combination.

The results of this experiment were that I got a great education on oils and waxes, and I now have a go-to homemade, tunable finish.

Hopefully, that's a satisfying enough answer. When I get my office back, hopefully I'll remember about this thread when I stumble upon that box, and post back. If not, necro post again, and maybe I'll get an email!