Leather Quality and Properties

[glenjay]



Yeah, I should have clarified that as far as I know crust leather is used for more antiqued finishes and such, (EG, G&G, Corthay...). I doubt most black shoes are crust leather, although there are a few manufacturers who dye their own black shoes as well.

In the cases where EG, etc... are dying the leather themselves, do you know if they are adding an acrylic finish coat?

 

[chogall]

In the cases where EG, etc... are dying the leather themselves, do you know if they are adding an acrylic finish coat?

They most likely don't from the feel of their shoes. They don't dye the leather *until* shoes are constructed, as opposed to dying the leather before construction.

 

[DWFII]



They most likely don't from the feel of their shoes.  They don't dye the leather *until* shoes are constructed, as opposed to dying the leather before construction.

A perfectly serviceable acryllic wax "top coat" could be added after the shoe has been completed. In fact, I suspect crust leathers would be the better candidate for such a finish than leathers that have already been given a finish coat.

On the other hand, the likelihood that the maker will heavily wax the shoes...for instance, bulling the toe...would probably make a subsequent finish coat problematic. I suspect the acryllic finish coat would not stick to the carnuba in most polishes.

And on yet another hand, high gloss acryllics can be significantly more flexible than a high gloss spit shine over the entire shoe.

 

[gyasih]

Thank you

 

[glenjay]



They most likely don't from the feel of their shoes.  They don't dye the leather *until* shoes are constructed, as opposed to dying the leather before construction.

I have a pair of JLP shoes in Museum Calf (as well as some other high end brands) and I certainly can't tell from feel if there is a light acrylic finish on them. Perhaps my fingers are not as sensitive as yours.

I suspect that a light acrylic finish is applied to protect the leather during shipping, storage, and so on. But I don't know for sure.

 

[VegTan]



Vegtan, Thank you very much for your usual, detailed and informative answer to my question about a pair of shoes. My only wonder is that a pair of shoes around £110 can be made of what seems to be good leather. Thanks again.

I am not sure, but It is possible if leather is tanned and/or shoes are made in a low-labor-cost country.

In regard to the finished product sold as a shoe, do non-corrected grain shoes come without a chemical finish and are simply aniline dyed and pressed smooth, or is there usually a finish coat applied to protect the leather?

It is said that casein is used, but I've never seen it.

http://www.leatherchem.com/leather-chemicals.html

http://www.hewit.com/skin_deep/?volume=8&article=2

Aniline / Casein Polished Finish

The aim of this type of finish is to produce leather, which retains its "natural" look but at the same time achieves a degree of uniformity in colour with the minimum opacity necessary. This is achieved by using a mixture of aniline dyestuffs and pigmented dyestuffs bound together using casein. Pigments, unlike dyestuffs are insoluble in water or solvents and are opaque. Casein, a protein that comes from milk exists as a water-soluble colloid. It is not unlike albumen (known in the bookbinding world as 'glaire'), which is the protein present in egg white. Binding takes place by the deposition of the binder around the pigment due to the loss of water by evaporation and also hydration of the leather fibres. Pigmented dyestuffs would not themselves adhere to leather or form a "film" so, as in the case of ordinary paints; other materials such as casein must be mixed into the finish. For this reason caseins are known as "Binders".

The leather is first sprayed with a lighter shade than required of this mixture, then a transparent 'top-off' coat with a slightly darker shade is applied. The finish is then fixed using Cationic Casein. Cationic Casein is positively charged whereas most caseins are Anionic and are negatively charged. The reaction of the negative and positive charges meeting binds the two together forming an impervious layer.

Until fairly recently this type of finish would be fixed by cross-linking using Formaldehyde but because of today's strict health and safety legislation (e.g. the UK's C.O.S.H.H. regulations), we are no longer allowed to use formaldehyde in bulk productions.

The finished leather is then polished. The combination of the darker mixture and the burnishing effect on the tips of the grain enhances the final colour and gives a very attractive two-tone effect. This type of finish has all the workable properties of aniline finished leathers and is most commonly used in the production of our Chieftain, Clansman and Kinauld Goatskins.

"The Box Calf Finish is mainly based on the use of the natural milk protein, casein. After the glazing stage, which is performed with glass balls, this protein gives the leather an unrivalled shine and transparency. The finishing layer is very transparent so that the fineness of the grain of calf skins can be appreciated to the full". specifies the Technician from Puy. Finally, this full grain leather glazing with glass balls gives the leather its famous shine rendering it definitively box.

Any information on the finishing process (or lack thereof) would be helpful for me to understand this aspect of shoe leather.

I have never seen photos where shoemakers use chemicals except dyestuffs and shoe polishes/creams on the finishing of crust leather.

BTW, these discontinued Scotch Grain (Japanese rtw shoemaker) were made out of Italian crust leathers (black, brown, and beige) and its finishing was left to consumers.

http://sgrain3.exblog.jp/14645465

Some experiments on a brown crust leather.

http://item.rakuten.co.jp/scotchgrain/c/0000000147/

Kiwi neutral polish

Kiwi brown polish

Saphir Creme Surfine neutral cream

Saphir Creme Surfine light brown cream

Saphir Creme Surfine medium brown cream

Kiwi brown polish with malt whisky (high shine)

delicate cream (almost water)

wiping off Saphir Creme Surfine medium brown cream with remover, but almost nothing has changed

waterproofing spray

 

[Munky]

I am not sure, but It is possible if leather is tanned and/or shoes are made in a low-labor-cost country.


Yes, they are made in India.

 

[patrickBOOTH]

DWF, are pegs pre-made, or do you have to make them yourself? Also what kind of wood do you use?

 

[DWFII]



DWF, are pegs pre-made, or do you have to make them yourself? Also what kind of wood do you use?

Pre-made. We get them from Germany...they're lemonwood.

But pegging really gained traction here in the US during the 1800's. In fact, pegging machines were invented and used widely during and after the Civil War. Pegs were pre-made then as well--of hard rock maple.

The problem with US pegs today is not only the dearth of hard rock maple but the fact that all the peg cutting machines in existence in the US are actual Civil War era machines. A bag of US made pegs is likely to be alder and with so many "mutants" that probably less that 2 out of five are useable. The only reason they are still manufactured at all is that they are used as some sort of polishing medium (I've been told but I don't remember).

Earlier, pegs were made by hand...sort of . A block of end grain was needed and then a specialized plane was used to cut a "V" shape in the endgrain, first in one direction, then perpendicular to the initial pass. Then a heavy hand knife was used to split the pegs along the "V". And again to separate individual pegs.

Somewhere I have a lithograph of that plane.

 

[chogall]



I have a pair of JLP shoes in Museum Calf (as well as some other high end brands) and I certainly can't tell from feel if there is a light acrylic finish on them. Perhaps my fingers are not as sensitive as yours.

I suspect that a light acrylic finish is applied to protect the leather during shipping, storage, and so on. But I don't know for sure.

PM sent

 

[DWFII]



Earlier, pegs were made by hand...sort of . A block of end grain was needed and then a specialized plane was used to cut a "V" shape in the endgrain, first in one direction, then perpendicular to the initial pass. Then a heavy hand knife was used to split the pegs along the "V". And again to separate individual pegs.

Somewhere I have a lithograph of that plane.

Click on image to see it full size.

 

[cbfn]

What is the positive and negative effects of using remedies such as Filson Boot Oil or Obenauf's Leather Oil on regular calf as used by C&J, AE, etc.? I use Filson oil on my rough boots, but I'm interested in what would theoretically happen if I were to use it on some more delicate leather. Would the oil do much more damage than harm? I have no plans of changing it out with my Lexol conditioner, but just wondering what theoretically negative effects it would cause.

 

[patrickBOOTH]

Well, I have used Obenuef's on calf in the past. Basically it soaks into the leather really well, but it also makes it near impossible to get a shine because it is so oily. Also, the oily texture that it leaves attracts a lot of dust and dirt.

 

[DWFII]

If the leather is not an oil stuffed leather, keep such products away form your shoes. Not only will the oil permanently change the grain surface and make shining your shoe impossible, in some instances it will actually lift the finish.

What's more, mineral/petroleum based oils are not good for the leather--suffocating it, and will rot non-synthetic threads as well.

 

[patrickBOOTH]

Obenaufs isn't mineral/petroleum based, fwiw. Apparently 100% plant derived.

What do you mean, "lift" the finish?