Glues and Cements

[dw]

Paul,

I don't doubt it. I thought I remembered Sharon talking about leaving her brush in a jar, but I always wash mine right after use with warm soapy water. I've been using water based contact cement (latex) for years and you have to wash your brush out immediately.

Tight Stitches
DWFII--HCC Member

[dw]

Re: Titan DX and ChromeXcel, Here's a photo of a folded edge (very close-up) of ChromeXcel using one coat of Titan DX as the cement. It is a very strong bond with no sign of slippage due to the oil in the leather.

12740.jpg

Tight Stitches
DWFII--HCC Member

[dw]

Here's a possible solution to the Titan DX/brush problem (I am very hopeful with early tests)

This is a Le Crueset silcone condiment spoon I picked up the other day. I saw a photo in the Goetz catalog (or somewhere) of a small plastic or silicone spatula being used to spread glue. So...

12761.jpg

12762.jpg

As you can see it is small, and it has a concave surface on one side so that you can scoop up a small quantity of cement before spreading it.

I used it on several pieces of leather today (shank covers) and it worked almost as well as a brush. It's a different feel so you have to get used to it but it spreads the cement evenly and quickly.

It also cleaned up extremely well even after I left the cement on the spoon to dry. In fact, the photo is were taken after use and clean up.

Not saying it's the sine qua non but I was happier with it than I thought I was going to be.

Tight Stitches
DWFII--HCC Member

[ccs]

Has anyone ever figured out what "press cement" is exactly?

ie, is it nitrocellulose (exploding billard balls etc) dissolved in acetone, essentially similar to duco cement?

Or is it cellulose acetate (safety film, etc) dissolved in acetone, essentially similar to "testors extra fast drying wood cement" ?

Also kind of wondering why it would be discontinued - of solvents, acetone doesn't in quick research seem to currently be viewed as being nearly as nasty as things like toluene.

Perhaps there are other ingredients? Anyone have an MSDS on a genuine press cement, or vangrip etc replacement?

It's also kind of interesting to think about the leather vs. celastic debate from the chemistry perspective - couldn't it be argued that in one case you are soaking an acetone-carried cellulose "plastic" into a natural matrix, while in the other you are forming a plastic impregnated fabric matrix with acetone and/or MEK?

(Message edited by ccs on January 28, 2011)

(Message edited by ccs on January 28, 2011)

[dw]

I think some "press cements" are one, some the other...and some are formulations that contain chemicals that will make you physically sick--nauseous.

But when I first started using press cement...as a sealer for leather build-ups on lasts...it was known as "celluloid cement." And it has a long, long history in the shoemaking trade--ostensibly back into the late 1800's.

I have been told that the human body naturally manufactures a certain amount of acetone as a by-product of metabolic processes.

As for the "question"...personally, I think there's a significant philosophical difference between using celastic as a toe stiffener and using celluloid cement to seal and adhere leather toe stiffeners to the vamp.

On one hand you have a leather toe stiffener. Some folks will use paste to seal and stiffen. Aside from the fact that paste is neither water resistant nor cockroach resistant, it's a good approach. Some will use PVA, some hide glue, some will use AP. But it all starts with leather and all that implies.

On the other hand, celastic is a "made material." In its present form it is nearer to a reinforced plastic than found materials. In my opinion, there is little significant difference between using celastic and cutting up a plastic bleach bottle and using that for a toe stiffener. The major difference being that at least using the bleach bottle remnants requires the maker to shape and blend the stiffener into the lines of the last. That being a good thing in my book as it encourages the maker to actually engage--think and make judgments about line and aesthetics.

Then too, in my personal opinion, using plastics, which generally speaking are almost universally petro-chemical derivatives, raises so many other questions...about environmental impacts, about the intrinsic nature of a "bespoke" shoe, about the reasons we make shoes, the nature of "craftsmanship" and/or quality and even about the future of the Trade. None of which seem amenable to quick or expedient solutions, from my point of view.

Personally, if I could rid my shop of all petro-chemicals--from All Purpose cement to nylon thread to rubber heels, and still meet both my own and my customer's expectations for quality and longevity, I would. And that included celluloid cement even though it may not be petro-chemically derived.

These notions may or may not resonate with everyone. Just as questions about quality vs. quantity ("speed kills," as who should say), style vs. substance, production values based on mechanization vs. skilled hands, or bottom line vs. high hopes may not resonate with some. No harm, no foul. There's room enough for everyone.

Tight Stitches
DWFII--HCC Member

[ccs]

Arguably off topic, but what I was thinking was that in the celastic case you have fabric fibers providing tensile strength and plastic providing stiffness, while in a leather stiffener you have leather fibers providing tensile strength and soaked in cellulose plastic providing stiffness - both are really engineered composites.

(Interesting question if it's easier to clean the wastewater from the manufacture of refined cellulose or the tanning of leather - both of which have historically been polluting industries)

In terms of press cement, I still think it would be interesting to see an msds for the actual stuff, particularly to see if there are any other solvents listed.

Also, since many have commented on recycling dried cement with acetone that suggests that either we should be able to make our own if the solids are just cellulose or if it's something more special (like the right additions of plasticizers), it should be possible to supply/ship/store it in solid form that small quantity users could dissolve with locally purchased acetone.

(Message edited by ccs on January 29, 2011)

[dw]

I seriously doubt that significant stiffening is added to a leather toe puff when using celluloid cement. For that matter, I doubt that any of the common (and not so common) treatments add much. Flour pastes, hide glues, HirschKleber, don't really add a whole lot simply because they don't penetrate much. Nor, in my experience, does celluloid cement...or, what I'm beginning to work with--Titebond III. Sometimes the glue creates a rigid (brittle even) substrate that sits on top of the leather. But none of them penetrate the leather beyond the thinnest margin. Their main purpose is to create a bond between the various layers--lining, stiffener and vamp.

But I suspect it's a red herring in a way to compare tanning effluent to cellulose run-off. The real comparison is tanning and cellulose run-off to the shrimp estuaries proximate to Dow Chemical. Or any other petro-chemical plant.

And yes, I agree it is a bit OT. But when you sit, daily, in a miasma of toluene and MEK for near on to 40 years you start to think about these things...with what few brain cells survive. And you start to take precautions...either that or you become so stupefyingly brain numb that none of it matters.

The further question is "where does it end?" Do celastic toe puffs lead to celastic heel stiffeners? Every bit of contemporary and historical evidence says "yes." And when do fabric based celastic toe or heel stiffeners yield to cardboard based celastic or fiberboard stiffeners? When do leather insoles become too costly, too time consuming, too "irregular" that leatherboard insoles become the norm? Indeed, even the "standard?"

When does a bespoke shoe become simply a wholly mech-fabricated foot covering? When does the concept of a wholly fabricated foot covering demand its own cadre of aficionados and perhaps, even its own forum?

And more importantly why do we, as bespoke shoemakers, want to emulate, duplicate, or adopt, as standards worth aspiring to, methods or materials that are almost entirely the province of mechanization and the devaluation and abandonment of human skills and input?

Weighty questions for sure but, IMNSHO, the logical extension of choices we must make.

Or not...depending on our level of engagement.

Tight Stitches
DWFII--HCC Member

[ccs]

I guess I'm misunderstanding... if the press cement isn't causing the stiffener (and I'm actually thinking counters and whatever I nail through into the heel, since I want sock-soft toes) to be stiff, then what is? When I soaked what I thought was a fairly thick piece of veg tanned leather (like belt stock) in water and let it dry bound to the last with wrappings of string, it adopted that shape but remained quite soft and flexible... I assumed the problem was lack of any cement soaked into it. Did I really just start with the wrong leather?

[romango]

I believe a key characteristic of press cement is that it is completely water impermeable. Its addition to the toe box would make that a tough toe box for work boots, cowboy boots, etc.

The usual process is to make the toe box out of leather, shape the leather by filing and shaving and then apply the press cement. The press cement allows a little more shape refinement, but not much.

Acetone is not carcinogenic but it is still mildly toxic (Oral, rabbit: LD50 = 5340 mg/kg) and highly flammable. The flammability would be the key shipping hazard. One interesting characteristic of acetone is that it passes through the skin readily and carries anything dissolved in it through too. My concern with press cement is not to have any nitrocellulose or acetate carried into my body. Though it might add to my explosively good looks.

I can't tell what Vangrip 2639-1 press cement from Midwest Industrial chemical is made of. They don't say. But I suspect it is nitrocellulose as I would expect the cellulose acetate to have a faint smell of acetic acid, which is one of its decomposition products.

You can read more on nitrocellulose here: http://en.wikipedia.org/wiki/Nitrocellulose

[dw]

You might have. But more than that the press cement/paste/glue bonds the lining to the stiffener...that adds rigidity..and the stiffener to the vamp (or counter cover). And that also adds rigidity.

Each of the above mentioned glues and cements has its own dry-state rigidity that is unquestionably additive to the whole construct but it is rather like plywood in that the veneer glue doesn't stiffen the veneer so much as it is the multiple layers that create the rigidity.

As with the plywood, you are relying on the leather to stiffen the toe/heel area not the cement. With celastic, if the cement weren't there you wouldn't have any bonding or stiffening effect at all--the fabric is dern sure not going to contribute much.

As for the leather you are using, two things need to be remembered...some leathers are better for stiffening than others. I use insole shoulder...sometimes as thin as 2mm.

And the other thing is that shape has a lot to do with structural rigidity too. A domed shape of 2mm leather may be sufficient all by itself to hold the shape of a toe but with or without glues, cements or other treatment, once it's flat it has no shape or rigidity.

I have actually been surprised at how rigid a 2mm stiffener can be with nothing but HirschKleber...which never seems to get brittle hard.

Finally, even if you're making slippers for the Pope (by legend the lightest of footwear), you still have to consider function. You can't expect a wish and a prayer to stiffen or support the heel no matter how much press cement you stick down in there.

So...shape, bonding (thickness) and materials.

Tight Stitches
DWFII--HCC Member

[ccs]

Apparently I used the wrong leather. It shaped nicely to the bottom of the heel area of the last - a shape that should be quite self-reinforcing. But a week later it remains as pliable when dry as the piece I cut it from was before it was wet in the first place. I just put it to soak in a mix of water and white glue, just curious to see what that would dry like since the supplies were already on hand, but I don't expect much.

[dw]

If the leather will absorb water and there is sufficient PVA dissolved in the water, it will indeed act as a stiffening agent. I tried this with TiteBond III. The result was amazingly hard.

Elmers white glue is not waterproof, however...although I have never tested it to see what it would take to soften an already set bond.

It's probably a good solution to the problem if you want to take the time to experiment with differing recipes and then take the time to soak, mount and allow 24 hours plus to dry.

It's a technique that I have promised myself to fool with in my dotage.

Tight Stitches
DWFII--HCC Member

[ccs]

Soaking in the white glue and water for about 8 hours just made it start to smell like... a tannery? When dry the next morning no real change from the untreated condition.

[dw]

That surprises me. Although I used Titebond III for my experiment, I would have thought that white glue would have worked just fine.

Either the leather didn't pick up the glue or the glue mixture wasn't "stiff" enough or white glue won't work the same as Titebond III does.

BTW, thinking more over your questions about heel stiffeners, it is perhaps important to ensure that you are using a vegetable tanned leather.

Any piece of insole shoulder...or outsole, for that matter...can, when wet and brought back to the proper temper, be hammered to compact the fibers. Thus hardening the piece. Chrome tanned leather won't do that.

But for instance, you can take belly cuts from a bend and wet them, dry them back to dry colour and when "hammer jacked" they will be as hard as wood...literally. That was one, if not the most important, use for the old "lap iron"--to hammer jack outsoles, heel lifts, toe puffs and stiffeners.

Tight Stitches
DWFII--HCC Member

[ccs]

My blacksmith anvil is in storage a state away, but I did try hammer jacking using the work surface on the back of a bench vise... it compressed maybe 20% but still not changing fundamental property. I'm kind of wondering if maybe the leather I'm playing with is oil tanned... it doesn't seem to be chrome or veg.

I don't have a local source of veg tanned leather, so trying that would mean placing an order specifically for it; I'm a little hesitant as it doesn't seem to be the solution used in the shoes that have worked best for me as an end user. Would I get anywhere with low grade tooling leather pieces, or would I need to get a whole insole shoulder?

(Message edited by ccs on January 30, 2011)

[tomo]

Chris,
Oil tanned is chrome tanned leather that has been treated with oil - often engine oil as a method of finishing.
Veg tanned leather is usually some shade of brown inside when you look at the cut edge. Chrome tanned is usually always some shade of grey. Tooling leather is veg tanned and yes that would hammer jack but it would probably go thinner than a insole shoulder only because it's more mellow.

You could check by wetting the cut edge with your tongue and a bit of spit then rubbing the wet edge with a smooth wooden tool handle or course cloth like canvas or even your jeans. Veg tanned leather will polish and go smooth and glossy as it's been burnished. Chrome tanned will not.

Chrome tanned leather uses chromium salts and I would include Allum tanned leather here as well and also 'retans' which are a blend of chrome and veg tanning (which doesn't burnish like straight veg tanned). Veg (vegetable) tanned is tanned with tannin extracted from trees such as Wattle or Mimosa and some other trees including Oak (Hermanns Oak tanned)


More power to y'awl
Tom.

(Message edited by Tomo on January 30, 2011)

(Message edited by Tomo on January 30, 2011)

[ccs]

Well, okay, guess it's not oil tanned. The mystery piece guessing games continue. Actually, it bears a degree of resemlance to the belt now residing in my knock-around jeans... which if I recall came at a low price with a "composition leather" label attached. Slicing into the mystery piece there's a thin dense layer at the grain side, and then a sort of chunky thickness which might be consistent with that idea.

Whatever it is, it's clearly not suitable for much other than belts or around-the-house slipper soles.

(Message edited by ccs on January 30, 2011)

[dw]

Well, hammer jacking requires a somewhat specific moisture content and then after hammering the leather needs to dry thoroughly to achieve maximum rigidity.

But it seems to me that if it were indeed veg tanned and you had the right moisture content and were to attempt to hammer jack it, you'd know right away whether it was compressing and whether it was veg tanned by the way it compressed and stayed compressed.

Tom is right. This is a mistake...of terminology, if nothing else (and one I fell prey to early on in my career)...there is no such thing as "oil tanned" leather.

And no offense or disrespect intended...but give this just a little more thought. Shoemakers have had literally thousands of years to evolve and to categorize leather and tannages suitable for certain applications. This is not a random process nor a mystery requiring any serious amount of guessing.

And to the extent that synthetic materials are suitable for certain applications they generally mimic the leather considered most appropriate for that application.

Whether you use leather or fiberboard, is up to you but I suspect you're not going to see much success until you focus on the characteristics of the materials needed to fulfill any given function.

Tight Stitches
DWFII--HCC Member

[ccs]

The "guessing" was to the identity of the locally sourced mystery piece in my possession.

It's entirely the characteristics needed for an application that's focusing my search for materials. For example, I need to find something that I can nail (or more likely in experimental context, woodscrew) through to attach a 6/8 or so heel, where the nail/screw heads won't shortly rip through. Presumably the right grade and thickness of vegetable tanned leather treated with press cement or tightbond III or whatever would do this, I'm curious what more readily available alternatives I may be able to find, especially since that structural role does not seem to be being filled by leather in the satisfactory solutions that I have disassembled.

A lamination of several thicknesses of polycotton shirting with gorilla glue seems interesting, though I end up with something more of a heel counter weight than a heel carrier one. I know I've got a scrap of denim left over from weighting the tails of my tailcoat project around here somewhere...


(Message edited by ccs on January 30, 2011)

(Message edited by ccs on January 30, 2011)

[tomo]

Chris,
If you have a look at cheap crappy ladies shoes, the ones with a fibre board insole you'll see that the heels are usuall attached with a huge flat headed staple with three or four spikes that go down into the high heel.

Tomo

(Message edited by Tomo on January 30, 2011)

[ccs]

I suppose I could dome a piece of sheet metal with a ball peen hammer and drill some holes in that.

Actually, the one experimental shoe that's had a heel added so far has a thin section of polycaprolactone plastic molded to the shape of the bottom of the last (last was made of the same stuff) for the screws to go through.

(Message edited by ccs on January 30, 2011)

[noonan]

Gents;
Just add a tuck board to insole. Nail with inside heel nailer using correct ring nail. When nailing by hand, I have used sheet rock screws. Held strong, just three well placed screws.
Tim

[ccs]

Tuck board as in the green board google says Georgene and Rick and Jenny were discussing for dance shoes back in 2007? Yes, I may have to look into that!

But I've got my gorilla glue bottle and $1 per 100 plastic gloves and if I could just fine that old pair of jeans or scrap of denim I'd launch today's experiment.

(Message edited by ccs on January 31, 2011)

[noonan]

Unfortunately, if you wanted to use tuck board as we do,like from Bontex or Texon, You need to buy huge minimum sq. yardages.
Used to be able to take away the scraps back in the old days, and for the small shop, that was quite enough. Check with Paul Freedman over at Lewis Sales. Thats the kind of stuff you might get lucky with over there. Explain just what you want. But he is truly the last resort nowadays. So sad, but that's the way the world turns man.
Good luck...
Tim

[ccs]

That's why I kind of keep hoping to find that something comparable is also sold though industrial supply/maintenance houses as gasket stock or something like that... but no luck so far.