Yellow glue offers some degree of tack, so you can sometimes perform these tasks with this glue. But even still, today’s hide glue creates just as good of a bond as PVA wood glues. One slight disadvantage with hot hide glue is that the parts being glued need to be warmed first. Hide glue has some drawbacks compared to modern synthetic glues, so it’s generally only used on antique furniture or where there is existing hide glue on an existing project. Animal bones, or at least the sinew in the joints, can also be used to make glue. Q: Why is hot hide glue preferred by some luthiers, while others use synthetic glues, and what are its advantages and disadvantages? What first attracted me to liquid hide glue is the long open time – it takes all the stress out of glue ups. Eventually, mold will form on the surface of the glue. And even though Old Brown liquid hide glue technically does not need to sit in a hot pot to activate it, you still may find it difficult to work with in a cold wood shop. Depending on the size of the project, the color and type of the veneer being used, the equipment on hand, the shape of the project (flat or curved). A few minutes of this will do the trick every time. Simply rinse or wipe with hot water. God has blessed him with a beautiful family, as well as a passion for teaching others about woodworking. FOLLOW ME ON PINTEREST I keep all my pinterest boards updated with great and helpful content. The glue is then dried and ground into Grape-Nuts-sized granules, which is the form in which it is usually sold. In fact if it gets wet, the glue may reactivate and potentially let loose a joint. Tight clamping eliminates foam in the glue line which can cause weakness of the assembly. It requires no mixing, heating or stirring. (Actually, I think the bad reputation began in the 1950s when manufacturers claimed superior strength and water resistance for their white and yellow glues to get craftsmen to switch. Most hide glue is sold in granular form. Hide glue makes all of that much less of a problem. If you are using a hot hide glue (the kind you have to melt) you may find it very smelly. People who are over exposed to polyurethane experience health problems including allergic reactions, rashes, difficulty breathing, loss of consciousness and even blindness. Animal glue was the most common woodworking glue for thousands of years until the advent of synthetic glues, such as polyvinyl acetate (PVA) and other resin glues, in the 20th century. Dealing With Rapid Tacking Then heat the glue to about 140-150°F so it becomes liquid. If you use hide glue often, an electric glue pot is worth buying. Liquid hide glues do not smell very strong at all, so they’re easier to be around. Even though it may not have quite the bonding strength traditinoal hot hide glue has, it still produces a glue joint stronger than the wood itself. Hide glue: Dry hide glue, $12–$18/lb or $50–$55/5 lbs plus shipping, Bjorn Industries, 704-953-2026. Subscribe here. Though it’s fairly easy to remove white and yellow glues by soaking and scrubbing with hot water or vinegar, no freshly applied glue redissolves into these glues. Now one of the disadvantages to hide glue is that it can tend to gel up fairly fast. It reacts with the material or surface you applied the glue on and then releases heat for sticking the two objects together. It cools quickly becoming tacky, and fully dries at around 24 hours. And we all know the same just can’t be said with other wood glues…. But the tack is much weaker, so the slightest pressure during drying will move the parts and destroy the bond. Applying epoxy in a damp environment on a … Keep in mind that gelling, which can cause a thick glue line on parts clamped edge to edge, is less of a problem in housed joints. Reversibility is the quality that makes redissolving possible after the glue has dried. Now and then, you’ll have to add water to replace evaporation. An initial tacking occurs when the glue cools from its application temperature of 140-150° Fahrenheit to about 95°F. The chair I used for illustration was made in the 1920s or early 30s. You want the glue to be about the viscosity of yellow glue. – Simple Woodworking Projects, In my last story (April 2007, issue #161). After being neutralized with an acid, the hides are heated in water to extract the glue. Glass artists take advantage of hide glue's ability to bond with glass, applying hide glue to glass. About The Author Adam has been woodworking for the last 10 years. Once you prepare hot hide glue, it can go bad fairly quickly. In the old days, cabinetmakers stacked furniture parts next to the shop stove to warm them. Hot hide glue has to be prepared in advance and applied hot. Another way to extend the working time of the glue is to add some urea. You cannot apply varnish over PVA but it can be painted over. In fact if it gets wet, the glue may reactivate and potentially let loose a joint. You can also strengthen case furniture by regluing old glue blocks or by inserting new ones. And finally, yes it has a long open time (liquid hide glue, not hot hide glue). Their findings were that they are both great contenders and held their own in various tests of strength, reversibility, and ease of use. It is made from bovine leftovers like hide, hooves, and bones. The point is, traditional hot hide glue can be difficult to work with, and so is avoided by most woodworkers (understandably so). You can always add water or more saturated granules to adjust the viscosity of the glue. Plus it’s not water-based, meaning it doesn’t swell the wood fibers (another reason PVA glue joints get tight so quickly). He uses Titebond hide glue a lot, and his biggest reason is because the glue makes it easier to slide the joint together. Most hide glue is sold as a solid in granular or pearl form. Liquid Hide Glue Standard grades range from a high of 512 grams, called “512 gram-strength glue,” to a low of 85 grams. As with any glue, it is possible to create a leaky joint. Professional woodworkers use Titebond Liquid Hide for its long assembly time, exceptional strength and unique crackling effect on wood. Bob Flexner is the author of "Flexner on Finishing," "Wood Finishing 101," and "Understanding Wood Finishing. Any kind of joint that fits tight and would be hard to clamp together if/when the wood swells using PVA glue, then hide glue may be the ticket. With all parts together, the assembled pieces would be moved to a cooler room so the glue could harden. gets its strength from animal protein. Hot hide glue becomes permanent and … The material does not adhere well in a moist environment such as a basement. Hide glue is still available today, and is sometimes used in book binding and woodworking (especially on antique furniture). On the other hand, if you don’t like the positioning of the pieces, you can separate them for some time before the bond becomes too strong. This page may have affiliate links. Higher gram strengths gel too quickly to be useful in woodworking. Here’s How To Get Started. It’s not bad at all. I think going forward I will be using Titebond’s hide glue more often in my projects. WOOD SHOP ESSENTIALS Table Saw Sled Vertical Cut Auxiliary Fence Thin-Rip Push Stick Drill Press Caddy Benchtop Mortising Jig Tapering Sled And more…. That means it’s still plenty good for wood projects and if used and applied properly, should create joints that last a really really long time. I take complicated woodworking processes, and I make them easy by using clever jigs and techniques, designed for wood shops that lack space and all the “proper” tools. And the fact that PVA will not stain with the wood, it makes itself incredibly noticeable after I apply the stain to a glued up project. It’s a good (but not absolutely necessary) practice to remove the majority of this skin from the glue pot, using a stirring stick or brush and throw it away. PW. The grades are measured by how much weight, in grams, it takes to make a dent in a 12.5 percent solution of gelled glue a given amount. Factories made a “steam room” with temperatures as warm as 120°F for gluing up. Once it fully dries, the bonding is incredibly strong. Antique furniture and instruments both have a need for disassembly (repairs and maintenance). The disadvantages of PVA Glue are as below: It can be degraded and broken down by algae, lichens, bacteria, and yeast. Also helpful are laying the parts out logically and dividing complex objects, such as chairs and case furniture, into sections, assembling each separately before assembling the entire unit. If the yellow glue is applied to solid wood and then the veneer is place on it, fine. Depends on: if you need to apply the yellow glue to the veneer it won't work out well. In our 'hurry up and get it done" society, hide glue has lost favor because it is not an easy product to use. Titebond 2 is an excellent wood glue, it doesn't smell, it sets quickly and is very strong. Disadvantages are that it must be heated to use it (a bother), it has a short working time (bad for … Otherwise, you can place a jar of the glue in water placed over a heat source (creating a double boiler situation), or heat the glue in a microwave. If using mechanical clamps isn’t an option, a well performed rub joint is a great solution for joining two parts. The best argument for using hide glue is to stay true to the original when making reproductions. Another benefit that I love is that it sets up hard so it can be sanded, scraped, and cut easily. The glue takes getting used to, which means using it regularly for a while. This is probably the biggest reason it’s used in woodworking. The initial tack allows you to glue two pieces of wood together without clamps. Nevertheless, hide glue still has a number of disadvantages compared to modern adhesives. Hide Glue White glue (PVA woodworking glue) Yellow glue (aliphatic resin) Urea resin formaldehyde glue Epoxy glue Contact cement. Very long-lasting glue (except for the moisture thing). It allows you to reglue loose joints without first having to remove the old glue (to create clean wood). If the basement floor is dried and prepared in advance of the epoxy application, you can avoid the adherence problems. It helps to have the glue warmed up a bit to help it flow better. In my last story (April 2007, issue #161) I discussed regluing doweled chairs. As with all glues, hide glue has its disadvantages. This is because it (specifically Titebond) dries dark and is stainable. The most common glue used in woodworking and furniture restoration is 192-gram strength. Initial Tack However, Super Glue is mainly a brand of adhesives rather than a variety of it. Yes, you can reactivate the glue by applying heat and moisture to the joint. We may receive a commission from sales referred by our links; however, we have carefully selected these products for their usefulness and quality. Other adhesives, including polyurethane, epoxy, plastic-resin and cyanoacrylate, can’t be broken down. Be sure to sign up below to get updates on blog posts like this one, plus I’ll send you some free plans. The biggest benefit of hide glue is that it’s reversible. is that they will not adhere to themselves or to old hide glue. Simply remove any loose or powdered glue, apply fresh hot hide glue, and reassemble. Hide Glue. The hides are washed and soaked in lime for up to a month to break down the collagen. Each subsequent extraction produces a lower grade of glue. Because hot hide glue is more difficult to use than modern adhesives, it’s not likely you use it for your projects. Various shop jigs, table saw sleds, and tricks of the trade have served him well. — BF. We may receive a commission when you use our affiliate links. Disadvantages and Advantages Be sure to cover the glue tightly so it doesn’t dry out. Traditional hide glue is pliable when it’s heated up, and as it cools it becomes very adhesive. It requires heating and mixing to get the right consistency and tackiness for the job. These non-issue claims are still used today by suppliers of even stronger and more water-resistant adhesives.). Hot hide glue is very useful in restoration, however. Martin, back in the day, would put the bridges and … The English Woodworker posted an article as well. For 192-gram strength, I find the ratio of 2-2⁄3 cups of water to one pound of glue works well. I have used a combination of heating devices countless times when my shop was cold to create enough time to get all the parts together. And it makes separation of sound glue joints possible by injecting hot water, steam, vinegar or denatured alcohol (which crystallizes old hide glue). But all hide glues sold for woodworking create a bond stronger than the wood itself as long as the wood is clean and the parts fit snugly. I’m not advocating you switch to hide glue, at least for new woodworking. The heating process is done a number of times to extract all the glue. So it’s helpful to work in a heated shop or to even preheat the joint. But with hot hide glue, due to the gell setting factor, it is possible to make every joint as perfectly air tight as every other joint, while with carpenter glues, this is just not possible. Hide glue can bleed through the veneer, reactivates with heat, and takes much longer to dry than other glues. So I won’t have to worry about ‘accidental reversal’. Advantages to hide glue are that it dries very hard, does not "creep" (move) under pressure, and new hide glue will disolve old hide glue, makeing repairs easier in some cases. Disadvantages: Water-based finishes could soften hide-glue joints. If there are inside corners in your glue joints, which will have squeeze out that’s very difficult to remove, hide glue can be helpful. You can’t glue air spaces. The answer depends on what YOU mean by “strong.” Also note that hot hide glue is superior to bottled hide glue. If a mistake were made during a glue up, you can actually back up and fix it. Position them correctly and let the glue dry to complete the bond. A tight glue joint, especially a complicated one with multiple simultaneous joints using PVA glue, starts to stick and sometimes require a little extra finesse from a rubber mallet. Liquid hide glue, specifically the stuff Titebond came out with, works just fine at room temperature, plus it has a long open time. If you leave the glue heating for a while, a lighter colored skin will form at the surface due to contact with cooler air. Adherence Problems. With the lack of time, space, and proper tools, he always finds ways to get great results without over-complicating or over-thinking the process. What is Hide Glue? This product is mainly a kind of cyanoacrylate compound that attaches two surfaces utilizing exothermic reactions. Or reduce both amounts, keeping to the same ratio, if your needs are less for the job at hand. Shepherd recommends putting hot hide glue joints in clamps overnight but warns that the clamps must be applied before the hide glue gels or the clamps can break the hide glue and ruin the joint. The water in the other glues may cause problems with uneven warping. Think about where you’re going to use it. So if you can’t remove all remnants of squeezeout, it’s easier to make it blend in and match the wood color by staining. Hide glue gets its name from the fact that it comes from animal hides, bones, hooves… (I’ll stop there). It’s rare that today’s repairmen recognize the glue, so what are the chances tomorrow’s will? So there’s little likelihood they will take advantage of hide glue’s easier repairability. Hot hide glue apparently can be finicky to work with. From us he therefore receives a clear recommendation! It can be applied to very complicated glue ups that require a lot of different glued surfaces (like a dovetail box). Typically, yellow glue is thicker and tackier than white glue. Both are far more useful for repairing old furniture glued originally with hide glue than for making new furniture. Titebond Liquid Hide Glue is the first hide glue to be offered in a liquid, ready-to-use form. Simply apply the glue to both surfaces and rub the pieces together to work out the excess glue. And this is just some urea, 46-0-0. And as Christopher Schwarz also wrote on the Popular Woodworking website, he uses Titebond hide glue for almost all his basic joinery needs, and loves it. You can use a rub joint to replace broken pieces on carvings, small pieces of veneer, and other parts that would be difficult to clamp. “True” hide glue needs to be heated – but can be applied with a brush. I know people who use a Crock-Pot. Unfortunately, hide glue has several disadvantages. However, this type of glue foams when it cures so clamping joints tightly is critical during the curing process. It’s a very archaic glue that’s been around as long as woodworking has. Hot hide glue has to be prepared in advance and applied hot. As a tenon or dowel is slid into the mortise or hole, or as dovetails are assembled, the gelled “skin” on the surface of the glue is removed, exposing still-liquid glue underneath for some time. The bond becomes complete when the water evaporates out of the glue. These glues redissolve just like hot hide glue, but they don’t have an initial tack and don’t dissolve well into old hide glue unless applied hot. I don’t buy the argument that you should use hide glue on new furniture so it can be repaired more easily decades from now. If you have ever used hide glue, then I am preaching to the choir. Hide glue is organic material, so it rots in time. Save up to 68% on 7 issues of woodworking projects and tricks. Also if using the hot hide glue variation, you’ll find that it has a faster tackiness because as it cools down it becomes very adhesive. Sometimes I’ll use a heat gun, just to preheat the joints. Today it is used primarily in specialty applications, such as lutherie, pipe organ building, piano repairs, and antique restoration. Here are some supplies and tools we find essential in our everyday work around the shop. Even if you don’t use hide glue, you may still be interested in it, just as you are probably interested in old methods of woodworking. With this leather glue a durable and very durable connection is possible, the glue dries very quickly and has a solid price-performance ratio. Franklin, the manufacturer of Titebond, makes a widely available product called “liquid hide glue.” A similar product labeled “Old Brown Glue” is available at wpatrickedwards. The aroma becomes stronger and the strength, or tack, of the glue weakens. And because I finish my projects (typically) with polyurethane. Almost any hide can be used, including horsehides (“take the horse to the glue factory”). They may be a good choice when there are many parts to be glued simultaneously, such as on Windsor chairs. Related:PVA Wood Glue – What’s It Used For And Why It WorksHow To Choose The Best Glue For Wood ProjectsWoodworking For Beginners – Tools, Projects, and Techniques. To slow evaporation and the thickening of the glue, keep the container covered. Animal hide glue is made by decomposing the protein, or collagen, from animal hides. If you are using a hot hide glue (the kind you have to melt) you may find it very smelly. In modern times, however, cowhides are universally used. Rapid tacking is an advantage when performing rub joints, but a problem when gluing up furniture with numerous joints – especially in a cold shop. As the glue hardens it shrinks, chipping the glass. Reversibility and quick tack make this traditional method worth the trouble – sometimes. The Disadvantages: Once opened, doesn’t have a long shelf life. 3. This will protect the glue joints from moisture if something is spilt on them. -I don't see any disadvantages in it. —Doug MacKenzie, Cary, North Carolina A: Hide glue, animal glue, and protein colloid glue are names for adhesives made from the connective tissues of various animals.Used by woodworkers in a wide variety of forms for millennia, … So there is usually a lot of waste. Super glue is generally more popular with the global public. Complicated glue ups that require longer open time (working time) would be made simpler using hide glue. Glue squeeze out can be a pain to work with and eliminate from intricate glue ups and inside corners. As long as the pieces are not forced apart while the glue is still in the gel state, the tack is strong enough to create a good bond. This type of glue is typically used with a hot pot that holds the glue at a certain temperature (usually about 140 degrees F). Reversibility When frozen, its polymer is degraded and renders the glue useless. of glue and 2⁄3 cup of water so you have less waste. Hide glue can also be injected into joints or cracks as a form of filler or to ‘re-join’ materials together (Guitar Headstock Crack Repair Process Using Hide Glue) – the removal of old glue in this process is not required as hide glue bonds well with itself. So hide glue is definitely handy for these types of projects due to its reversibility. Both are the same as hot hide glue, but with gel depressants added to keep them liquid at room temperature and preservatives added to retard deterioration for about a year. 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