vamp leather question

[gcunning]

When selecting a vamp leather what are the pros and cons of roo compared to french calf?

[dw]

Gary,

I kept looking for this post--I thought it was over in "Sources"--but couldn't find it...it's a good question, however and I couldn't let it go unanswered...

what are the pros and cons of roo compared to french calf?

The simple answer is that each has its strengths. But, generally, it is the customer who decides when we use kangaroo and when we use french calf. That said, a bootmaker needs some way of describing the various leathers he offers.

Kangaroo is one of the lightest weight leathers that is available--usually between ounce and a half and two ounces. It is also the strongest in terms of tensile strength--it won't tear as easily as other leathers of the same weight. While it doesn't have as smooth a grain surface as calf, it makes up into a beautiful lightweight boot.

French Calf is almost the gold standard when it comes to men's boots or shoes. Depending on finish, it has a very smooth and dense grain surface. it generally runs around four ounces in weight and many people like that combination of dense surface and substance around their foot. Although it's not common, a good "struck-through" calf has got to be a mainstay in every maker's shop.

Personally, I like kangaroo as well or a little better than French calf for my own boots but I make boots for myself out of both...repeatedly--having a pir of each at all times.

Hope that helps...

Tight Stitches
DWFII--Member HCC

[gcunning]

Well, I was beginning to wonder If it truly was a stupid question. Thanks DW. I did find some information in one of my books. Your explanation is helpful. I did order a black roo skin from S/P and received it yesterday. It is really a smmmmoth skin.

[admin]

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Admin--06 May 2002

[Anonymous]

O.K. I've got a really stupid question. I've been making things from leather for about 25 years, and I never saw no "Grain". Where is it? I'm sorry but I can't see it. I'm gathering that it runs from head to toe on the hide. Also, that if you pull cross-grain it's supposed to be stretchier than with the grain? True? Anyhow, since I usually buy a hole side I can tell where it's supposed to be if this is the case. However, how should I be placing my patterns for the uppers, toe to heel with the grain? Why? Also, what about the sole?

[dw]

Anonymous,

I've always maintained that the only stupid question is the one not asked.

In regard to your question, I would suggest that you are perhaps confusing your terminology. You seem to be using "grain" in the same sense it might be used with regard to wood. But the word "grain" as it is used in reference to leather refers to a certain portion of the corium--the part of a pelt after it has been dehaired and fleshed. The corium consists of two parts, the upper and thinner part which is known as the "grain" and the lower and thicker part known as the "flesh." More commonly, I suppose the grain is the "hair side" but of course the hair has long been removed. Thus leathers that still have this thin layer and have not been buffed, are known as "full grain." And just to make things more complicated, sometimes the texture that occurs naturally or may even be imprinted on the surface of the leather, is called the "grain." Such as "scotch grain" or "pebble grain" or even "corrected grain."

On any piece of leather except a split, the grain is everywhere, not just running in one direction or another. In fact, "grain" doesn't really have anything to do with lines of tightness or stretch. These occur independent of grain. The direction of stretch, or tightness, varies with the area of the hide under consideration, although in the prime areas of the hide the lines of stretch are generally perpendicular to the backbone...and the leather is said to be "tight" in the same direction as the backbone.

Vamps are usually cut to stretch from toe to heel, so that when the shoe or boot is lasted the leather will yield in the direction of the first draft and also so that the boot will not walk out side to side. Tops for boots are generally cut to stretch across the leg so that a top will "open" up as the foot is going in and so that the tops will not stretch out, lengthwise, as the boot is being pulled on.

Soles are generally cut tight from toe to heel so that they will not distort and lengthen when flexed and walked.

Hope that helps.

Tight Stitches
DWFII--Member HCC

[michaelanthony]

D.W. & ?,

Two thoughts:

One: I was educated that the stretch of the hide runs in the same direction as the hair grows. True that it is usually opposite of the backbone. However, the exception that i have found to the backbone rule that supports the hair growth theory, is in the stretch of a kangaroo hide. The stretch of a kangaroo skin does indeed follow the direction of the hair growth, which in this case, is in the same direction as the spine.

Two: When laying-out vamps for a shoe, i was taught that the stretch should be cut opposite of what i normally would do for a boot. On a boot vamp, toe to heel. On a shoe vamp, side to side.

Stretching out and signing off,

Michael Anthony

[dmcharg]

G'day Michael,
I too cut for stretch side to side, which I find makes for a very comfortable feel ( as do my customers), though I thought that the roo was tight neck to tail and stretched from belly to belly (what stretch there was,as veg. roo is very stable). Have I read you right there?
I can get back on next week.

Cheers Duncan

[michaelanthony]

Duncan,

Yes, you read me right. I predominantly use the Italian tanned kangaroo. It has been my experience that the stretch travels the length of the skin, neck to tail. I have never used vegetable tanned kangaroo. Perhaps, the tannage makes some difference? Also, when you think of a kangaroo in action, (bouncing up and down), it would make sense that it would stretch in the same direction. We can call this new found idea, the "out-back-bone theory."

With my mug of non-alcoholic beer raised high to your cheer...

Michael Anthony

[dw]

Michael,

You may have more insight into this than I do. But all the text books I've read indicate that it doesn't make much difference whether the animal travels upright or not. Tight is still along the backbone. Fundamentally, I too, have it in my backpack of old wives tails (sic) that stretch runs with the hair. But hair grows in one direction or the other to shed water and dirt and not as some convenient (for shoe or bootmakers) indicator of underlying structure. Stretch generally tends to run *with* the direction in which the living skin has to stretch the most during day to day Existenze. That's why we see fat wrinkles in the neck and why Plucknett and Swayzland and others depict the lines of stretch changing in the neck and legs and belly. The neck is constantly swiveling in most animals, the legs are constantly moving, and the belly and chest expand and contract with breathing and eating. As the backbone is fairly rigid, the skin along its length changes very little. The structure of the skin evolved to not need to stretch in this dimension.

Having said that when I make full wellingtons, I am forced to cut the blockers parallel to the backbone. And it works fine.

Tight Stitches
DWFII--Member HCC

[George Ball]

Hi guys, I'm really Anonymous cause I couldn't get the password thing to go through. Anyway, this is great! Exactly the info. I was looking for, tight from head to toe stretchier at 90 degrees. I've read there somewhere also of placing a pattern, as the quilters say, "On the Bias", or like 45 to the spine. Is this ever done? G.B.

[dw]

George,

Among custom makers, I only know of one leather that is cut "on the bias," and that's alligator. There is a theory that cutting the hides so that the "tiles" do not run directly across the foot will make the boot last longer. The soft, and somewhat thinner leather under the edges of the tiles--the "interstices"-- tends to line up with the natural creasing that occurs with the flexing of the foot and then dirt gets in the creases and pretty soon the leather cracks.

And occasionally, I'll twist a vamp pattern **slightly** out of exact alignment to avoid flaws in the leather or, as with ostrich, to pick up more quill follicles. I emphasize "slightly," though..no more than 10-15 degrees.

On the other hand factories and even small manufactures may cut on the bias just to conserve leather--to get as many pieces out of a skin as is possible. But at that point, there is probably little or no concern about stretch or tightness in any direction.

Tight Stitches
DWFII--Member HCC

[shoestring]

Can any one tell me what makes one Kangaroo hide better than another other than it's tannage.Reason I have 3 hides comming from the Aussie's and it's the first time I have worked with it.Should I be checking for something out of the ordernary.Need some help here.
Thanks

[dw]

Edward,

I'm moving, and answering, your question about kangaroo over here where it's a bit more appropriate.

This is only one man's opinion ...others may feel differently...but I like a kangaroo that's a little heavier, more like two ounce than one and a half. I like a firm kangaroo and not one that is too stretchy. I like a glazed surface but not one that is too heavily painted. I don't want to see the leather bleed heavily or lose it's finish when exposed to water. The look I show the customer--sometimes called "table"--is what I want to present to the customer in the finished boot.

Look carefully at your skins and inspect for scars. Kangaroos fight and sometimes you can get leather that is nearly unusable, even from the best sources. I generally figure three skins for a pair of full 'roo.

Tight Stitches
DWFII--Member HCC

[Eisele's Custom Boots]

I see we have a disscussion on cutting up the roo, but haven't found any on cutting up the big bird. What direction is the vamp cut from an ostrich? Usually I buy pre-cuts, but this time whent for the whole skin.
Kevin

[Tex Robin]

Kevin,

I usually point my pattern to the middle and get as many as I can from a skin. But if you get two pair of fulls you are doing good. I like to do this because you don't want the quills to come up on the edge if you can help it. But I don't see
any diff in crimping whatever direction you cut them....TR

[dw]

Kevin,

When you purchase a whole skin, the mass of the quills are over the back. The margins are the belly and the neck, etc.. Remember that stretch usually runs perpendicular to the backbone in almost all animal hides except in the neck and leg areas where it can get somewhat unpredictable.

I know lots of people who cut ostrich to get as many full quill vamps out of the skin as possible. I've talked to fellows who claim that they can cut three pair of full quill vamps from a medium (14-16 foot) skin. To do this they have to lay out the patterns with little or no concern for lines of stretch and tight.

For myself, I always cut perpendicular to the backbone...with all leathers...if I possibly can. I don't worry about getting any more vamps out of the skin than doing it that way will reasonably allow. I pass the cost on to the customer and end up well paid and seldom if ever surprised by leather behaving in unexpected ways.

The worst experience I ever had was cutting some elephant trunk for position and ignoring the direction of stretch. After a real blowout with the crimping boards, I managed to salvage the leather for a pair of small ladies packers...where it worked fine. But I could not get the vamps to crimp evenly or nicely. I never ignore the lines of stretch and tight anymore.

Tight Stitches
DWFII--Member HCC

[Eisele's Custom Boots]

Thank you for the help. The hide is barely 14 ft. so I don't have a lot of room for error if I don't want to lose money on this.
Kevin

[gcunning]

Here goes ignorance again.
Isn't crimping supposed to take most of the stretch? Then you get more of it in lasting? If that is true how much stretch can be left to worry about?

[rileycraig]

Gary,

What I have found is...if the vamp is correctly cut from the hide, and crimped, you actually get more pull from the toe than from the sides. Thats been my experience, especially with ostrich.

Good Bootmaking,

Riley

[dw]

Gary,

My preference is to simply *crimp* the vamps. Think of what that means and what its real purpose is...you just want to get the vamp smooth on the board to give it shape and open up the tongue and quarters.

Taking all the stretch out on the boards is dangerous, in my opinion. It *is* possible to take a piece of leather to the point where there is no stretch...or life...left in it. It is even possible to take a piece of leather beyond that point and actually damage it.

If you take all the stretch out on the boards (or even come close) you'll have nothing left when you go to last it, and somewhere--in the waist or the arch, most likely--you'll be forced to take the leather further than it naturally wants to go...just to get the leather "tight to the wood."

Of course, you will take some of the stretch out on the boards, and that's the way it should be, because it helps you control the vamp when you actually last. But lasting is where you remove the excess stretch.

Riley,

You're doing something right because that's the way it should be...with all leathers except maybe the reptiles and that's partially because we are forced to cut them *with* the backbone and because the leather doesn't have much stretch in *any* direction, anyway.

Tight Stitches
DWFII--Member HCC

[joe]

crimping the vamps removes about 30% of the stretch and also pre-shapes the vamp for easier lasting. When lasting, rest of the stretch (65%-70%)is removed in order to hold the life time shape. Ageing is important, for about 2 to 4 days is sufficent.

[dw]

Joe,

I agree...and that's a reasonable ratio. I generally let my vamps sit on the boards several days as well, and I leave the boots on the last as long as possible, too...right up to the point of treeing them.

This business of "aging" is pretty important but sometimes it's just as important to let the leather age *off* the boards as well. For some, the following may or may not apply, but it's instructive nevertheless...

As you know I make a lot of full wellingtons. I crimp the front blockers on two different boards and leave them to sit on those boards about a week. I also crimp the backs. Ordinarily when I take a blocker off either of the boards, I let it sit and "relax" for about a week, as well.

I have been making a pair of full cuts out of some of that nice kangaroo from Sheridan Leather/Stevenson-Paxton. So I pulled the backs off the boards the other day and decided to lay out my back patterns and cut them while I was at it. The leather was beautiful and it all worked according to plan. About a week later I am ready put the pieces together and am about to cement the backs to the back liners. But wait! Something's looking odd here...a bit of fumbling around and a quick check and I discover that the backs have drawn up a quarter inch in length and a little less than a quarter inch in width. The paper patterns are now larger than the leather which was cut from them!

I had to cut a new set of backs. If I had tried to use them as they were, the boots would have been choked in the throat and never come down the cone of the last properly. A nasty lesson...seems like I always have to learn them the hard way...but thankfully I discovered the problem before it could ruin the whole boot.

Tight Stitches
DWFII--Member HCC

[gcunning]

I emphasized "most" and should have used % like Joe did. My point as Joe pointed out and seems, DW you agreed, most of the stretch is out of the finished boot. If you get most of the stretch out why is it important to worry about which way it stretches? Just get the stretch out. If there was say 5% more than desired stretch left after making a boot I could see wanting to know which way it would stretch. I'm not trying to debate anything I just want to know why you consider stretch when all your going to do is cut off the excess.

[dw]

Gary,

Ah! Well, that's a good point and a good question. The answer lies more in how lines of stretch and tight affect not only the process that we apply to the leather but the finished product, as well.

Here's an example...If you cut a vamp to stretch across the foot, sometimes the leather will distort while crimping--the quarters will draw down so that cutting a tongue is harder and maybe even end up too far down the vamp. Or given that you do get the tongues and quarters cut nicely, the quarters may draw down during lasting--distorting the "line" from vamp tongue to counter cover tongue. Maybe even resulting in a "dip" right where the quarter should be level.

Additionally, stretch across the vamp means tight the length of the vamp. So maybe the vamp doesn't pull far enough forward during lasting. Maybe the throat never opens up...and the end result is the boot sitting too high on the last and the counter completely divorced from the back of the last.

And when the boot is worn, it doesn't really matter how much stretch you have removed, the leather will still be more apt to stretch along the lines of stretch than along the lines of tight. So if you have 5% or 10% of the stretch left in the fully lasted boot (and there will always be *some* left) the boot will stretch in that direction...and in no other. If, by chance you get 100% of the residual stretch removed during lasting then any ease that the foot and the movement of the foot imposes on the leather will simply cause the leather to fail that much sooner.

Better to think of stretch as "elasticity." And elasticity is *good*, it equates to resilience and "life" in the leather, same as in the untanned living skin. It's more prevalent in one direction than another...and taking it all out only kills the leather.

Hope that helps...

Tight Stitches
DWFII--Member HCC