What went wrong?

[Moresnowdays]

Would olive oil ever go rancid? I've used mineral oil to treat wood, but never heard of anyone using it on leather. Mink Oil as good as nfo?

[Tugadude]

If you rough up the leather you can use less cement and it should dry faster.  Tap with a smooth hammer to help bond.

[heydox]

Olive oil like any other animal/plant oil can go rancid. If you do want to use it in place of nfo, choose an extra virgin olive oil from a company you feel confident is giving you a quality oil. Extra virgin should mean you are getting a pure, cold-press olive oil without additives, but like anything else, those two words on the bottle aren’t a guarantee. Honestly though, you’ve gotten your answer to the cracking problem- a quality, wetted leather won’t need a coat of nfo or evoo to make a bend like that. I would only suggest a light coat of oil if you continue to use the water-based dye, they do have a reputation for “drying” leather. I’d recommend making the switch to Fiebing’s oil dye. 

Edited March 3, 2019 by heydox

[bermudahwin]

Casing leather and bending skin to skin first, will give some stretch, prior to bending flesh to flesh, it loosens the fibresjust enough, usually.

Just my 0.02

H

[NVLeatherWorx]

Tandy leather is hit and miss for the most part and that is why anyone who is serious about creating nice looking finished pieces should invest in the better quality leathers.  Besides, a person can get the best leathers at wholesale for much less per square foot than the best grade from Tandy; I do it every time I order my leather (I get Hermann Oak for $7.95 a square foot and it isn't the low end stuff; and that is the everyday wholesale price that anyone with an account would pay).  Stay away from vegetable based oils for conditioning, they can go rancid as others have said and it also attracts unwanted critters; it is a food stuff and they can smell that a mile away (or more).  And, as has been mentioned several times already) always dampen any fold lines on the flesh side (fuzzy sied) of the leather and let it penetrate a bit before you fold it over.  This allows for the leather to be more flexible and by doing it on the flesh side you won't be risking some discoloration that you are sure to get on the grain side.  Basically, you have been given several tidbits of information on everything that caused an issue for you and if you put all of them to use in your process you will find the success that you are looking for.

Like the accent pieces that you put together for this one, gives it a bit more eye-catching detail.

And don't over oil.  You used the term "liberally" when mentioning how much oil you applied which typically means that you applied quite a bit; this can give the leather too much conditioning that will now not set and your leather will become spongy and won't accept adhesives very well regardless of whether or not you sand/rough up the contact areas for the glue.  Too much oil will also result in color bleed no matter how much you buff; it has nowhere to go but out.

Edited March 3, 2019 by NVLeatherWorx

[Moresnowdays]

Thank you all for the help on this one. In the next day or so I'll try to post some update picks if it works out. I decided to cut off the pen loops. I pulled it back apart rather easily and removed the glue. Then I scratched up the glue areas good and glued it back together. Held very well this time. The leather may not be the greatest, but I finished stitching it up and burnished the edges. Looks good so far. I was going to wet the spine to get it to bend right, but I was wondering if I would get a waterline if I only did that part. With the reinforcing decorative parts I added I didn't think a light dampening would be sufficient. I decided to soak the spine for a few seconds and then soak all of it for a few. I have it wrapped around my glass burnisher drying. Hopefully I'll have a decent project when I pull it out to finish it tomorrow.