Stamp/dye or dye/stamp?

[Laird_M]

ok, quick question for the leather workers amongst us...

Currently working on a sporran project and need to find the best route to follow for dyeing/stamping.

If you're working with undyed veg tan leather, do you mark out, dye then stamp, or mark out, stamp then dye?
The books that i have don't really cover this...

[Tobus]

Dyeing comes last. You'll need to do the stamping/tooling on wet (cased) leather, so obviously this needs to be done before any dye is applied. After the stamping is done and the leather is allowed to dry fully, then you can dye and finish.

[Paul Henry]

My experience is with fine quality leathers ( usually goatskin or calf) and on veg tanned ones, I would always dye/stain finish before any decoration. I use heated brass tools to make the impressions, sometimes blind , sometimes with foil or gold, and for the marks or design to remain crisp it has to be the last action. If I am making lines I wil often dampen the leather a little first and then use a hard edge bone folder to make the lines or decoration.

[Father Bill]

When you're tooling, will you be making cuts before stamping? If so, by dyeing first, you will reveal the natural colour of the leather at the points of cuts and the cuts will need to be extremely skilful. If you tool, then dye, the dyeing will cover up a multitude of errors.

[Tobus]

My experience is with fine quality leathers ( usually goatskin or calf) and on veg tanned ones, I would always dye/stain finish before any decoration. I use heated brass tools to make the impressions, sometimes blind , sometimes with foil or gold, and for the marks or design to remain crisp it has to be the last action. If I am making lines I wil often dampen the leather a little first and then use a hard edge bone folder to make the lines or decoration.

paulhenry, I must admit I'm intrigued by your reply. I have never heard of anyone doing it this way. I wonder if this is just a difference in techniques from different continents, or if maybe we're talking about different things. Either way, I'm very curious about what you described! I'd like to ask a few questions if I may.

1. You mentioned using heated brass tools. What is the purpose of heating the tools? And how hot are they when you use them?

2. What do you mean by "blind", and can you describe a little more what you're doing with the foil or gold?

3. What is a "hard edge bone folder"?

Just for reference and to make sure we're talking about the same concept, I assume the OP was asking about the usual sort of stamping designs/patterns into everyday vegetable-tanned (tooling) leather. All the photos below are of my wife's work, as I describe the process that is pretty much standard over here, for the benefit of Laird_M. I'm including "tooling" in the process, even though it's more involved than simply "stamping", but it involves the same basic steps and procedures.

Typically, the way it's done here by every leatherworker and saddlemaker I know is that the leather is first cut from the hide to the desired shape. The pattern is transferred to it either with tracing paper and a stylus, or by using a "beat-off pattern", and then it's set in a basin or tub of water to soak. The general rule is to leave it in there until it sinks. It's then removed and laid out flat. This requires a bit of experience with tooling to know when it's too wet or too dry. It has to be at just the perfect moisture level. If it's too wet, they let it sit for a while to air out. If it gets too dry on the surface at any point during the tooling process, they use a sponge to wet it again. But the leather has to stay moist inside so it can be stamped (allowing the fibers to compress). They call this "casing" the leather. Often, when stopping for the day, they will cover the leather or put it inside a plastic bag so it keeps the moisture in. Obviously, all of this water would be problematic if the leather had already been dyed.

The tooling process starts on the cased leather by using a swivel knife to cut in the pattern. I don't often take photos of her work during this part of the process, but here you can see what swivel knife cuts look like on the saddle horn. While the rest of the saddle is (obviously) tooled and finished, she chose to leave the feathers on the horn as simple swivel-cuts. This is basically what the leather will look like during the process: just raw cuts that are deep into the leather.




After the design is cut in, the stamping/tooling begins. Depending on the complexity of the job, it may take days. And it will involve a lot of re-wetting, touching the leather with your hands, and other activities that would obliterate any dye job. Not to mention that a quality tooling or stamping job needs to be deep into the leather, often breaking the surface of the hide. But when the tooling is done and the leather is allowed to dry, it will look something like this:




As another example, you can see how deep the tooling needs to 'cut' the leather in order to raise the pattern of whatever you want to accentuate. In this case it's the oak leaves. This sort of thing would mess up any dye job on the leather, requiring it to be dyed all over again.




Anyway, after all the tooling and stamping is finished and the leather is completely dry, then it's assembled and dyed (the order of this depends on the product). I know that typical Scottish kilt-related accessories tend to be brown or black, but you might consider not dyeing the whole thing a dark colour, as it will hide the beauty of your tooling/stamping job. Often, simply oiling the leather and finishing it can bring out the natural beauty. Or consider only dyeing part of the design to highlight certain parts.

Here are examples of how you can accentuate the pattern by dyeing only the deeper areas and backgrounded parts, or even using an airbrush to create a colour gradient on the piece. See also my previously posted photo of the saddle horn, but look down at the rest of the saddle to see how it really makes the pattern "pop". Obviously, this can only be done after tooling!




Alternatively, you can simply "antique" the piece, which will just darken the deeper portions of the stamping. This photo is actually something I made about 6 years ago, and you can see how the antiquing tends to highlight the pattern. Again, this can only be done after stamping.




And of course, you can simply dye the whole thing a uniform colour. But again, this will really tend to hide the tooling/stamping and make it hard to discern the patterns, as you can see below. It can look very nice, but it just won't showcase your work as well as the other choices! Instead of the colours accentuating the pattern, you have to rely on the light reflecting off the pattern to do the job. So my advice is if you want to dye the piece a dark colour, finish it with a shiny/glossy finish to bring out the pattern.




I apologize for the long-winded reply and plethora of photos, but I think it's fairly obvious that if you're doing an in-depth stamping or tooling job, dye simply cannot be applied until the work is done. With that said, though, I'm still very curious as to paulhenry's methods. There's always alternative ways of doing things, and it sounds like a completely different way of going about the work.

[Paul Henry]

Tobus, I don't want to derail the topic too far either, but here goes!
I split my time between bookbinding and kiltmaking, similar in quite a few ways, the folding and pleating of the fabric or paper and the careful sewing of each. My book binding has always a very traditional structure ( the insides and the sewing ) but the covers are often very different, I use leather a lot, but also wood, or glass, or fabric or ceramics, even tartan from time to time.
With the leather bound volumes you have to do any surface decoration when it is on the book, not before, so therefore any dye work has to be done beforehand, then the difficult bit of marking the design happens on the actual book itself, so there isn't a second chance.Traditionally brass tools are used to impress the leather surface, and these have to be just a little too hot to touch. but not much more , in order to actually mark the leather properly, if you do it directly on the leather it's called blind tool work - because there is no colour in the lines or words, unlike if you use gold leaf or other metal foils, which using need some sort of glue, and the favourite one is egg white. Because most of this work is very fine and detailled any additional moisture or wetting afterwards may have the effect of softening the detail. A hard edge bone folder is simply a length of polished smooth flat bone with a narrow sharp edge which can be used to mark the leather by creating lines and the like. I've got lots of pictures on my website of the type of books I make, please have a look, and I'm more than happy to answer any more questions!

[Tobus]

Oh, I don't think it's derailing the thread at all. This is precisely the topic at hand.

Your explanation makes perfect sense. Doing the stamping 'in situ' on a bound book would indeed require delicate workmanship and dry leather. I understand completely. Thanks for the clarification!

[Truitt]

Dyeing comes last. You'll need to do the stamping/tooling on wet (cased) leather, so obviously this needs to be done before any dye is applied. After the stamping is done and the leather is allowed to dry fully, then you can dye and finish.

***

With vegetable tanned leather you generally case it, carve/stamp it, trim/bevel/burnish, then dye and finish it.

[Laird_M]

Thanks folks - I kinda supposed that dyeing would come last, but as I've only just started using dyes, wanted to make sure I got it right.