Has anyone seen this type of damage to a wet formed saddle?

[timesofplenty]

This 1930s bicycle saddle was recovered in the 1990s, the person that covered this one passed away many years ago.
Originally these saddles were formed veg tan top and bottom, with a layer of canvas between the leather and (felt or sponge rubber) padding on top and leather and metal pan underneath.
This saddle was not reupholstered as original: the leather was wet formed then glued to neoprene padding. 
Here's what someone has suggested as to why the leather cracked in this way:

"Although I do like the looks of veg tan leather...which is typically soaked
so that it can be 'formed' to the contours of an object or seat pan, the inherent problems
with the process is the soaking. The leather...has a tendency to
'rot' or decay from the inside out, the side of the leather that comes in contact with the seat
padding etc. I have seen a number of...saddles that have had the 'cracking from
within' occur. bummer. You are looking at the result of the process when it goes south. Thorough drying once covered is key to avoid the
potential for what you're seeing in the pix, but still no guarantee."

I've done a fair amount of wet forming, talked to many leatherworkers, and have read many articles and books on leather and leatherworking. 
Never have I encountered anything to support the assertion that what said above is true. 
Can anyone shed some light on this?

[chrisash]

Was the cracking due to the sun and dry climate of LA

[VYO]

I am not sure about that seat but I have had leather crack on me. This wallet cracked before I had finished it. I chalked it up to bad leather. There was no wet forming involved.

[bermudahwin]

It depends on the method of wet forming, as some of the old cycle saddle makers would use heat and water to form the firmer saddles. Cuir boulli or boiled leather can have some odd side effects if not fully done in the usual manner.

It does not really need boiling, and I have done 3D workd by slow drying very well cased leather in an oven set for meringues, so just very gentle heat over a long period.

If the leather was not wet enough when formed, of it was dried too quickly or with too much heat in an industrial setting, if would/could be susceptible to damage as it would be brittle. I have a cycle saddle that I neatsfoot oil every 6 months, and it has been on the bike since about 1985, and is still functioning well.

It is just a suggestion, but seems plausible to me. Wet forming and allowing to dry naturally should not have the same issues.

If making Bombards, Bottels and Blackjacks, another method was to use heated sand to force out the Bottel into a bottel shape; some of the techniques made the leather as hard (and brittle) as wood, and was used for armour.

H

 

[timesofplenty]

1 hour ago, chrisash said:

Was the cracking due to the sun and dry climate of LA

I don't think so, I've left some of my saddles outside 24/365 for a few years to see what happens and nothing like this developed.

I do not use glue, if that lends any clues.

[bermudahwin]

My misunderstanding, I'd looked at it generically.

I've never come across rot at all, let alone a tendency...

Shape of saddle supports on the frame may have caused structural instability, but rot is unlikely to manifest in this way, with sharp edges.

H

[nrk]

quite simple - not enough conditioning - it just got too dry

2 hours ago, VYO said:

I am not sure about that seat but I have had leather crack on me. This wallet cracked before I had finished it. I chalked it up to bad leather. There was no wet forming involved.

same here

[NVLeatherWorx]

There is a chance that the glue used may have had some part of this but the overall culprit here is a total lack of maintenance and care on the seat, @nrk has pointed out.  Anytime that leather is wet it needs to be dried completely and then conditioned to replenish oils so that it maintains its strength.  Leather also loses these oils when it is exposed to heavy sunlight which dries out these oils.  And, if you don't use a leather item frequently, sometimes even daily, it will not absorb any of the natural oils from skin or other contact and will dry out.  Cracking like this is the result of being drier than a scorching Summer day in Death Valley, and I can tell you from experience that is a type of dry that you do not want to experience for yourself.  

The cracking issue that is associated with the carved and tooled image is again the result of inadequate conditioning and it was also most likely a bit older piece of leather that had been sitting around for awhile.

[timesofplenty]

Thanks everyone, 'zacly what I thought. The person quoted in the OP has repeatedly claimed that there is "danger" in wet forming "vegitan" leather, that "moisture becomes trapped" and causes the leather to "rot from the inside out" if the piece isn't "dried correctly".
Never have I had a problem nor heard that from anyone experienced in leather working. dude is such a loudmouth about it and says it so often that I wanted to get some other opinions....I guess hearing bs over and over can make us question what is true   

Edited January 9, 2019 by timesofplenty

[Les No6]

On 09/01/2019 at 3:45 PM, timesofplenty said:

Thanks everyone, 'zacly what I thought. The person quoted in the OP has repeatedly claimed that there is "danger" in wet forming "vegitan" leather, that "moisture becomes trapped" and causes the leather to "rot from the inside out" if the piece isn't "dried correctly".
Never have I had a problem nor heard that from anyone experienced in leather working. dude is such a loudmouth about it and says it so often that I wanted to get some other opinions....I guess hearing bs over and over can make us question what is true   

Yes oxidation caused by iron oxide from the steel seat pan tell, Black staining in the cracks at the pressure points. Tannic acid is an antioxidant preservative which has a high affinity for iron oxide so it strips all the tanning from the leather and the leather oxidises and as water rots the steel inside the saddle it will rot from the inside out. So don’t listen to bs (see above) and stop questioning what is true.

[Les No6]

On 08/01/2019 at 4:15 PM, VYO said:

I am not sure about that seat but I have had leather crack on me. This wallet cracked before I had finished it. I chalked it up to bad leather. There was no wet forming involved.

Yes you are right bad leather, they’re no natural oils in skin the only thing oil does is increase oxidation and cause embrittlement by no means does it hydrate your leather, on a scorching summers day in Death Valley if you where to rub hoof oil into your skin you’ll burn to a crisp and so will leather.

[timesofplenty]

21 hours ago, Les No6 said:

Yes oxidation caused by iron oxide from the steel seat pan tell, Black staining in the cracks at the pressure points. Tannic acid is an antioxidant preservative which has a high affinity for iron oxide so it strips all the tanning from the leather and the leather oxidises and as water rots the steel inside the saddle it will rot from the inside out. So don’t listen to bs (see above) and stop questioning what is true.

the black your seeing is the black neoprene that is glued to the steel pan.