Nick Horween’s Leather School: What Is Loose Grain in Leather, and Why Does it Occur?

Welcome to the inaugural edition of Nick Horween’s Leather School, where the fifth-generation tanner from Chicago’s deservedly famed Horween Leather Co. offers unique insight into leathers of all kinds and their properties, especially through the lens of very darned good footwear.

First up: loose grain! An occurrence in leather that plenty of people have seen or heard about, but not enough quite understand (including myself) (until now).

[Important note: the consensus is that the grain break in the hero photo above is NOT loose grain. But it’s rare enough that I don’t have any on my boots, and there aren’t a ton of photos sexy enough for a hero shot out there. Which is a good thing.]

Portions of this conversation were part of a Stitchdown Shoecast episode in which Nick was a guest.

Believe it or not, we talked about a LOT about leather from basically every direction. If you’re interested in shell cordovan or other Horween leathers, or really about leather and footwear at all, I’d definitely say it’s worth a listen.

Ben: Ok, so let’s start out with a somewhat obvious one: what is loose grain in leather and how would you describe it?

Nick: I think coarse break is probably a little more accurate when talking shoes specifically, but it’s really the same thing. Loose grain is wrinkling or creasing of the top grain that is more pronounced than is acceptable. And it’s generally caused when the grain is pulling away from the layers below.

Ben: Interesting—should we all be using different terminology then? And switch to coarse break?

Nick: It’s the leather industry so it’s all made up words.

Ben: Haha well weren’t all words made up at some point?

Nick: Pipey or pipiness works also. I guess the distinction should just be made between “bad” break and coarse or loose. There are multiple causes so it’s hard to be specific.

Ben: With “bad” meaning…

Nick: Even leather with a “tight” break can be forced to be loose, if it’s lasted too hard or the pattern is problematic.

Ben: Right, right.

Nick: I’ll step back, I think that looseness can either be inherent to the leather or caused by the making of the boot or how it fits.

Ben: And on the inherent side, is that due to the nature of the raw material, would you say? Or the tanning process?

Nick: To a large degree it’s the raw material, but there are also tanning processes that have an impact. I think it’s the challenge of the tannery to keep break/grain in good shape as far down into the belly as possible. Some of it is controllable, but much of it isn’t.

Ben: Got it. Visually, what would you say is the best way to identify it?

Nick: If part of the shoe that flexes is creasing or wrinkling in a pronounced or markedly different way than the rest of the shoe/boot, then looseness might be a consideration.

Ben: So it’s tough to say, which I understand. I feel like pretty much everything with shoes is on a spectrum. But there’s often confusion here, so what would you say is NOT loose grain, again from a visual standpoint?

Nick: That’s also so hard to answer. If someone is used to fancy calfskin, anything could look loose to them. Loose isn’t necessarily bad, I just think it really falls on what the customer wants cosmetically. If you want your vamps to look perfect then you need to buy cordovan or suedes or flesh-out leather.

Ben: And with flesh-out stuff, it may still be happening but you just don’t see it, is my understanding?

Nick: With a flesh out the grain is bending the way it wants to, that is, not back against itself. The flesh won’t pull away the way the grain does, it’s just a structural thing. And suedes generally are splits so there is no grain to speak of. With something like a nubuck it could happen and you’d still see it.

Ben: Ahhhh so you’re saying I don’t understand anything.

Nick: But also the pattern and the fit have a lot to do with it. Less desirable break, we’ll call it, can have to do with the lining sometimes. I’m not shifting the blame off of us as the tannery, but that loose break, that pebbling and creasing, is happening because the surface of the leather is bending around a shorter radius than the back of it is, if that makes sense?

Stitchdown: I think so.

Nick: It has to travel the same distance as the flesh side of the leather, but it has less space to do it. So the only place the grain can go is out away from the leather itself. So it’s forcing, or wants to force that front layer to delaminate, which effectively causes the inside of the hide to become softer and squishier, so that it has the space to go and do what it needs to do.

So if you have a very firm lining, that can exacerbate that, if that makes sense. You can get loose grain on any leather. And delaminate isn’t really the right word, but it starts to get pushed outward.

The other thing that can cause that look in shoes is if it’s cut from a part of the hide that’s not really suitable for a vamp. So if it’s cut from a flank or the belly, it’s going to be more likely to exhibit those kind of break characteristics than if it was cut from where the backbone would’ve been, because the belly and the flanks do more flexing during the life of the animal, so the fiber structure is inherently spongier, which is going to accelerate all that stuff I just talked about.

One way to think about it is to picture a rolled-up magazine. The very inner page is bending around a tighter radius than the outer page, but all the pages are the same size. If all the pages were glued tightly together then the center roll would go away, but also put more stress on the glue itself and other parts of the paper. I’ll send you a photo [ed note: said photo is above].

Ben: Ohhhh fantastic, that’s really helpful. So is it purely an aesthetic thing? Or are there performance compromises of any kind when it occurs?

Nick: Not really the way people wear shoes. If you were logging in them every day in the rain then better break might be more water resistant and your boots might last 12 years instead of 11.

Ben: Haha got it. Might try it.

Nick: Performance issues means we’ve done something wrong or something has been cut into the shoe that shouldn’t have been. All this in very general terms of course.

Ben: Does loose grain/coarse break/whatever we’re calling it occur in certain leathers more than others?

Nick: In our tannery we are more likely to see it in certain leathers, but there are so many factors there. pH, chrome content, oil content, time of year which affects temperature and humidity, thickness. Then you can get into types of oils and waxes, and tanning extracts, and then you can get into mechanical processes—plating/ironing too hard to or too many times, milling too long, etc.

Ben: Sounds like you have a tricky job

Nick: It’s the wild west here. Oh and it’s an animal skin that’s different every time. Haha.

Ben: So just to be clear, if you have a boot that’s displaying this, the boot isn’t going to fall apart, or have that top layer become completely separated, or something extreme like that?

Nick: I’d say that’s unlikely when buying from a good shoemaker.

Ben: In terms of fit not being quite right, what exacerbates loose grain? Boots too loose? Too snug? How’s that work?

Nick: I’m a little out of my depth with this one, I think it can be an issue if the shoe is flexing too far forward or back in the vamp. Too loose, then you can get that double crease, the one high up on the vamp and one up towards the toes. Too tight, and it isn’t flexing where it’s meant to either.

I really think fit should be the first thing that gets dialed in. I bet someone would wear comfortable shoes that look ok, or uncomfortable shoes that look good, but not bad looking and uncomfortable. I mean, Crocs is a brand

Ben: Don’t tell anyone but I own a pair of Crocs.

Nick: I have two pairs. Haha.

Ben: But I only wear them in a boat, which I have to put into the water every time I use it to fish. Which involves going up to my knees in water. So, Crocs. The grain break on them is incredibly tight though, I have to say.

Nick: Plastic is forgiving. Or epoxy, or rubber, or whatever petroleum byproduct is used to make them

[Hugely important update: since this interview Nick has been tirelessly seeking out more information on Crocs. He found it. And got back to me: “I looked it up, Crocs are made from crude oil polymers, technically not a byproduct.”]

Ben: A truly sustainable product if there ever was one. So honestly that’s kind of all I’ve got, and I think it clears up a ton, for me at least. I could keep asking narrower and narrower questions but I feel like getting clear answers will be necessarily tougher, and maybe not make things more clear. Anything big we missed?

Nick: Maybe just that it’s easy to look at a pair of shoes and judge the break to be bad without thinking back up the chain. It’s an animal product, and we’ve tanned it to try to balance grain characteristic, specifications, and performance. And looks. And then we cut away a good portion—or all—of the “loose” areas in the flanks so our customers don’t see that. Then the makers have to cut the hide in a way that makes sense for the shoes, but for business, too. Every pair of shoes could have perfect break, but shoemakers would all need to operate like Edward Green.

Ben: Right, right. If that was the case I guess I’d need to somehow be happy with just one very expensive pair of shoes. but that’s a helpful way to think about it. Huge thanks for this Nick, really fantastic insight. Let’s do some more leather school soon!

Nick: My pleasure, anytime.