Tooling Or Creasing On The Fold

[Ellen]

I have seen here a fold over pouch sheaths, tooled or with crease around mouth, and can't wrap my head around the process:

Tutorials say that all tooling and creasing are done after cutting pattern from leather, when it's flat. Then dampen the leather and fold it over the knife, let it dry before gluing, stitching and dyeing.

But if tooling is done not only at front or back, but all over, and crease goes from front to the back and to the loop, wetting (or dampening with mist) and bending thick leather will flatten and distort the tooling and crease. I can imagine the same with making book or album cover, or a stiff tooled bag without separate bottom.

Is it the master's proprietary invention, or there is some standard operational procedure for this?

[BillB]

Ellen,

Let's analyze the problem. When making a bend in the leather we are asking the outer side of the leather to travel farther than the inner side. On bends with a very large radius, like the flap of a purse, that is no real problem. When the radius of the bend gets smaller then there is less leather involved and the fibers have to bend more. On toop of that, on very tight bends the leather on the inside of the curve actually puts force outwards onto the surface leather and actually pushes on the carving as well. In this case, one can remove some of the leather from the inside of the fold using a "V" gouge to do so. This will take practice so you don't remove so much leather that you cut into the bottoms of the carving, e.g. the cut lines that you made and then tooled and in some cases it can weaken the leather, so you don't want to do this on a fold that is also a stress point. Another way to reduce the problem is to use a lower weight leather depending on the project. A knife sheath does not have to be 8oz leather. I have made knife sheaths with just buckskin (@3-4oz) and I routinely tool 4 & 5 oz leather. In some cases, to add strength back to the leather, I will glue on a piece of pigskin as a liner, which creates a layering like plywood and adds strength, especially when I have made a mistake and actually driven the bevel through the leather. This can happen when using an undercut bevel. There are probably other ways and methods to solve the problem. This is the one I am most familiar with. I hope this helps.

BillB

[TwinOaks]

Very well stated, Bill.

I'd like to add that there are no rules that say that once a carving is bent or wrapped to it's final position, that the maker/user can't grab a modeling tool and dress the carvings a bit in their new position- i.e. tool it, bend it, then press the tooling lines back into place once the leather has been distorted.

[Ellen]

Sounds very reasonable, thank you both!