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VG1: How do I know which glue to use?
That depends on many factors. If you have a vacuum press and the substrate material for your project is porous, then certainly a veneer glue such as Better Bond X-Press is ideal. If the material is non-porous (such as glass, plexiglass, plastic, or metal), you may find it difficult to bond veneer to your project. More information on this topic is here.
The adhesives shown are those which are available at VeneerSupplies.com.
Other adhesives are available.
VG2: Can I veneer a panel if I don't have a vacuum press?
Yes! For those woodworkers who dont have a vacuum press, there are several options which can yield exceptional results. These methods can be an excellent springboard into full-blown vacuum veneering. Be sure to check out the "Veneering Without Vacuum" article.
VG3: What is a "cold press" glue and where can I learn more about veneer adhesives?
 Cold press glues are adhesives that do not require heat to bond and cure. It is probably the most common veneer adhesive type available. Better Bond X-Press is an example of this type of adhesive. I've written a comprehensive article about the veneer glues offered at VeneerSupplies.com which discusses various glue options including the cold press types.
VG4: What can I do to extend the open time on the cold press veneer glue?
Better Bond X-Press™ veneer glue has an open time of 10 to 12 minutes. For larger projects, this means you need to work quickly to get the project into the bag. But there are easy ways to increase the open time to as much as 20 minutes.
You can lengthen the open time by "priming" the substrate with a 60/40 mixture of water and cold press veneer glue. Brush or roll this on to the substrate and let it dry. The primer coat will seal the pores of the substrate so the water from the glue is not pulled out. Be sure to thoroughly scuff sand the surface with 60 grit sand paper after the glue has dried. This will add 5 to 8 minutes to the open time without affecting the adhesion. You can then proceed to apply glue to the substrate as you would to adhere the veneer to the substrate.
You can get even more open time by lowering the temperature in the shop. For some, this means turning down the heat. For others, it means cranking up the air conditioning or working in the evening when shop temperatures are lowest. Cooler temperatures slow down the setting of the glue. Don't go below 60° F or the glue may not cure at all.
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VG5: How much coverage will I get from a gallon of Better Bond X-Press™ veneer glue?
One gallon of glue should cover between 175 and 225 square feet of substrate material which is roughly both sides of three 4x8's.
VG6: What can be done to prevent the veneer from curling up as soon as it's laid onto the glue and substrate?
Veneers have a tendency to curl up quickly when they are placed upon a glue-prep'd substrate. Veneer softener won't work and sometimes spritzing the top surface with water creates problems in and of itself.
 I use a few small pieces of blue, "clean release" masking tape to hold the edges down.
I place a few strips on the top edge of the veneer before putting it on the substrate. I press the tape around the edges of the substrate as soon as I put the veneer down.
Note: Once under vacuum, the blue tape really sticks well to the veneer so removal can be tricky. So apply as little tape as possible for best results.
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 VG7: What is PPR glue and why would I use it instead of regular veneer glue?
Pre-catalyzed powered resin adhesives like Ultra-CAT™ are more heat/water resistant and create a type-II bond which is suitable for use in areas of high heat or moisture. This type of glue is also ideal for bent laminations and shop-sawn veneers.
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VG8: How much coverage will I get from a 5 lb pail of the Ultra-Cat™ PPR veneer glue?
One 5 pound pail of Ultra-Cat makes enough adhesive to cover 200 to 275 square feet.
VG9: Where can I learn more about Ultra-CAT™ veneer glue?
Powdered glues like Ultra-CAT are more heat/water resistant and create a Type-II bond. This type of glue is also ideal for bent laminations and shop-sawn veneers. The full instructions and product literature for this glue can be found here.
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VG10: Can I use X-Press™ veneer glue or Ultra-Cat™ for general purpose woodworking joints?
Yes. I use the X-Press veneer glue in my shop for all of wood to wood joints. The darker color and easier sandability over yellow glue makes it a great choice. Ultra-Cat can be used for wood to wood bonding and is especially useful for bent laminations because it dries rock-hard and minimizes spring back.
VG11: How do I know how much veneer glue to apply?
 The key to applying glue is to put it on evenly. I've found that, by far, the easiest way is to use a dedicated glue roller. I'm not talking about the $200 imported rollers with the glue hopper on top. I prefer something simple like the one shown on the right. Of course, you can get these at VeneerSupplies.com.
A good test to see if you have applied the correct amount of glue is to place a pencil mark on the substrate and apply the glue. If you can readily see the pencil line on the substrate (through the adhesive), you probably have the right amount of glue. If you can't see the pencil lines at all, then you might have applied twice as much glue as necessary. Learn more by clicking here.
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VG12: What is the difference between cure time, set time, flash time, etc?
Clamp or Set Time - The amount of time the veneered panel will need to be pressed.
Flash Time - The amount of time you need to wait before setting the veneer onto the glued substrate. For standard cold press veneer glue, this term is not used because the veneer can be placed onto the panel immediately after the glue is applied.
Shelf Life - The length of time that a product can sit unused and unopened.
Open Time - The amount of time between when you apply the glue and when the material is placed in the press.
Cure Time - The amount of time that it takes for the glue to fully harden.
Pot Life - The length of time in which a glue can be used after it is mixed (PPR's are mixed with water. Unibond is mixed with its companion hardener).
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VG13: Can I use yellow glue for veneering?
Yellow glue (PVA) is probably the first glue that comes to mind when you say "glue" to a woodworker. Despite the recommendations of many woodworkers, I have never found yellow glue to be suitable for veneering. This type of glue never fully hardens, and thus allows the veneer to "creep" or move during seasonal changes in humidity. And because of its thin consistency, yellow glue also has a tendency to bleed through and discolor the veneer. Lastly, since yellow glue dries with a soft glue line, it is also very difficult to sand.
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VG14: What is Heat Lock™?
Iron-on veneering is the latest craze in woodworking because it's easy, convenient, and inexpensive. This glue is applied to the substrate and the veneer back and allowed to dry. Then the veneer is placed on top and heated with a clothes iron. Heat Lock is excellent stuff... especially for small, curved and oddly shaped pieces. Click here to see how it is used.
This adhesive is not a replacement for a vacuum press; it's a complement to it.
VG15: My friend uses contact cement for veneering with raw wood. Should I try it?
 There is one big problem with contact cement. It doesnt dry hard. Wood veneer is just as prone to seasonal movement as regular lumber and the ability of veneer to expand and contract with seasonal humidity changes is greater than the strength of the contact cement bond. I have tried every contact cement I can find and nothing offers the permanent bond required by a raw wood veneer.
Contact cement is only good for paperbacked veneers and 2 ply wood veneers because the backing minimizes the veneer movement.
From a reader in Cleveland, Ohio...
"Here are the pictures of the banjo resonator. I used Weldwood contact cement. The resonator was glued and sat for one week before doing this. I put it out in the sun for about one hour. It heated up so it was noticeably warm to the touch. The back expanded but the veneer did not. The veneer pulled away from the sides of the back on the inside piece of veneer and cracked. The outside veneer pulled away from the bloodwood binding but not as much as the inside did.
I then put the back outside overnight to shrink the back. The back shrunk but the veneer rippled. The cracks did not close. The ripples were much smaller on the inside and cannot really be seen in the photo. The ripples on the outside are still there as seen in the photo. It has been 5 days since the experiment and the ripples are still there."
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VG16: What glue do I need if my veneered project will be outdoors?
To the best of my knowledge, the most user-friendly adhesive for an outdoor project is Ultra-Cat™ veneer glue. Keep in mind that it is not for use with projects that will be continuously wet.
VG17: I'm using a paperbacked veneer but the veneer glue isn't giving me a good bond. Any suggestions?
Test the back of the paperbacked veneer by applying a single drop of water to the backing. If there is still a bead of water after 5 seconds, then the backer is creating the problem with the adhesion. The solution is to scuff sand the backer with 100 grit sandpaper. This will allow the moisture in the veneer glue to transfer the bonding polymers to the paper backing and will give you the quality bond you expect.
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VG18: I want to adhere a piece of veneer to plexiglass, glass, or plastic. What adhesive should I use?
If you are planning to use a raw wood veneer, you may not find an adhesive specifically made to bond to plexiglass, glass, or plastic. Your best bet is to use a good grade of epoxy. You will need to heavily scuff sand the substrate to give the adhesive adequate "bite".
Paperbacked veneers can often be succesfully bonded to these substrates if you order the veneer with the PSA (or pressure sensitive adhesive) option. Learn more about paperbacked veneers and PSA by clicking here.
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VG19: What adhesive should I use to bond veneer to metal?
A few woodworkers have sent me email indicating success only with paperbacked veneer and solvent based contact cement (water-based contact cements will not work). Some users have reported excellent results using TC-20™ copper adhesive for bonding backed veneers to some types of non-ferrous metals.
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VG20: What is the shelf-life of veneer glue?
The shelf life varies from one adhesive to another but you can usually expect 6 to 12 months. Check the product labeling or website page for details. It's important to remember that the shelf life is unchanged regardless of whether you open the container or not. So if you purchase veneer glue, keep in mind that it could go bad even if you never open the container. You can maximize the shelf-life by storing your glue in a cool and dry place.
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VG21: How will I know if my veneer glue is past its shelf life?
For premixed veneer glues such as Better Bond X-Press Adhesive and Heat Lock, your nose will tell you the condition of the veneer glue. If it smells moderately funky (but tolerable), the glue is probably close to the end of its shelf life. It can still be used at this point though. However, if the glue smells extremely offensive and has a thick, lumpy, or oily feel, then it is past its life and should be discarded.
When powdered veneer glues such as Ultra-Cat PPR are past their shelf life, you'll notice that the powder is lumpy and sometimes crystalized. Once you start mixing in the water, the state of the glue will be very obvious.
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VG22: Since there is no air movement inside the vacuum bag, does the Better Bond X-Press glue actually cure?
With a non-catalyzed cold press adhesive such as X-Press glue, the bond is "set" inside the vacuum bag when the air inside the veneer and substrate is displaced by the adhesive. This typically takes 45 to 60 minutes to happen and then the panel is removed and allowed to cure outside of the bag.
There are some veneer glues that have a chemical or reactive curing process. Ultra-Cat veneer glue is urea resin glue which has a reactive effect when mixed with water. The water does not need to evaporate to cure the adhesive. With this adhesive, the set and the curing take place inside the vacuum bag over the course of 2 to 6 hours depending on temperature.
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VG23: If my panel doesn't come out right, how do I remove a veneer from the substrate?
There really is no easy way to remove veneer that has been applied with common veneer adhesives. The nature of the veneer glue is to make an exceptionally strong bond thereby making it very difficult toremove a veneer intentionally.
In some cases, you may be able to heavily sand the panel to remove the veneer and adhesive. Ultra-Cat veneer glue generally is the easiest to sand off because it doesn't gum up sand paper as much as other adhesives. However, in most cases you'll probably find it easiest to just remake the substrate panel and start fresh.
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VG24: Can I bond wood veneer to a solid wood substrate
The problem with solid wood is that it will expand and contract with seasonal humidity changes in the house. When a solid wood substrate is needed, most users will find that quartersawn lumber is ideal since it has less seasonal movement than flat cut lumber. Use a hard-setting PPR adhesive like Ultra-Cat and clamp the panel with a vacuum press for 4 to 6 hours while the PPR glue cures.
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VG25: Which color/tone of X-Press™ veneer glue should I use?
X-Press veneer glue comes in light, medium, and dark tones. It's a common misunderstanding that the color options are available only to minimize the visibility of the glue line at the edge of the panel but the glue line is very thin and it's typically not as visible as you might think. I've used the light tone Better Bond glue on a curly walnut veneer and the glue line was not visible at all.
The primary use of these color options is to fill the pin holes which are typically found in burl veneer. When working with a burl veneer, it's best to use a veneer glue that matches the color of the wood cells around the voids which are frequently darker than the rest of the veneer. Mappa burl is a great example of this color variance but more subtle differences can be found in any burl veneer.
Don't worry about true bleed-through affecting your choice in the veneer glue color. True bleed-through that comes through the face of the veneer is usually caused by using too much glue and in that case, it really doesnt matter which tone you use because any bleed-through of that nature will not look good.
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VG26: What glue should I use to apply veneer to the dashboard on my car?
If the substrate surface is porous, a PPR glue (such as Ultra-CAT™) is ideal because it cures rock-hard and it's moisture and heat resistant. Keep in mind that PPR glues require 4 to 6 hours of clamping time. If the surface is non-porous, the only adhesive option is epoxy which unfortunately is expensive and messy.
Despite the suggestions and claims found online that contact cement can be used successfully on a car's dashboard, I would never recommend it. Contact cement does not dry hard and it is not moisture and heat resistant. These are the three critical factors that make a durable bond on a project subject to the harsh environment inside a car.
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VG27: Can I use yellow glue to make guitar picks from several layers of veneer?
Yellow glue is just not suitable for any veneer work. I always cringe when I hear of someone doing this... which is quite frequent. Yellow glue dries soft and that is always a problem for veneer. A rigid glue line is needed for veneer. This is especially true when you are not veneering to a stable substrate. I have customers building guitar picks from multiple layers of veneer and they all use PPR glue because it dries rock hard and is designed for this type of laminating work
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VG28: What can I do to make sure a maple veneer bonds perfectly to the substrate?
Maple veneer can be a challenge to bond. Even solid maple lumber can be troublesome which is why this species is often the reference wood used by glue manufacturers when testing an adhesive. Whether we are referring to veneer or lumber, there are ways to improve the bond.
Glue-related issues on a veneered panel are typically caused by the failure of the glue to penetrate the surfaces to be bonded. The wetting agents found in all veneer glues work to make the adhesive polymers saturate the pores of the wood and substrate. This is how the adhesive gets its "bite" on the surfaces. Some of the wetting agent will flash off or evaporate once the adhesive is spread onto the substrate. The rest of the wetting agent will absorb into the pores of the materials being glued together. The key is to make sure the wetting agent saturates the pores of the project surfaces. Here are some tips.
- Always scuff sand the substrate with 80 or 100 grit sand paper. This will remove any burnishing that prevents the wetting agents from penetrating the surface. If the substrate is plywood, particle board, or MDF you can be sure that scuff sanding will greatly improve the bond strength.
- The slicing and press-drying of a maple veneer can cause the wood cells to become non-porous. So it's always a good idea to open the pores again by scuff sanding the back of a maple veneer. In fact, this is true of any species including the exotics. Any kind of shimmer or light reflection that can be seen on the surface of a veneer should be considered evidence that scuff sanding is needed. Doing this allows the wetting agent in the adhesive to flow adhesive polymers into the wood cells.
- It's a good idea to work especially quick when using a maple veneer. If the adhesive is open to air, then it is obviously drying out and the wetting agents are evaporating.
- Be certain to have adequate pressure on the panel. Most professional woodworkers agree that significant pressure is needed to force the adhesive into the pores of the veneer (especially maple) and substrate. A vacuum press is the ideal tool for creating evenly distributed pressure on a veneer panel.
- A bit of investigative work is neccessary when a veneer does not bond well to the substrate. Use a razor knife to cut open the area where the veneer did not bond. If the glue is bonded to the veneer but not to the substrate, it is typically because the surface was not made porous by scuff sanding.
If you find that the glue has bonded to the substrate but the veneer has no evidience of adhesive penentration, then it's best to evaluate the veneer preparation and adhesive mixing process. Did you scuff sand the back of the veneer? Did you mix the glue with the correct amount of water (assuming you have a glue that requires mixing)? Did you spread the adhesive too thin? Did you wait too long before applying the veneer to the glue surface and getting the panel clamped? Did you use enough clamping pressure? With these answers and the information provided above you may be able to determine the cause of the issue.
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VG29: Why can't I clamp the veneered panel for more than 60 minutes?
Cold press adhesives such as X-Press cure by evaporation. In a vacuum or mechanical press, there is very little air movement at the glue line and because of this, there is very little curing. If the panel is pressed for too long, mold can form on the veneer. This is especially true with cherry and maple. Clamping for more than 60 minutes can also allow the glue to over-saturate the substrate and cause swelling.
For cold press glue, press the panel for 45 to 60 minutes, and then let both sides of the panel dry/cure outside of the press for 3 to 4 hours.
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VG30: Why do thick veneers require a PPR glue?
Generally speaking, veneers over 1/32" require an adhesive that creates a ridiculously strong bond such as a PPR glue. Here's why. Seasonal changes in ambient humidity cause veneers to expand and contract. The potential for movement or "creep" is far greater with thicker veneers and so an adhesive that has an exceptionally strong bond is required.
Standard thickness veneers lack the strength-in-numbers (of wood cells) and typically can not overcome the bond from a standard cold press veneer glue.
It is important to note that standard yellow glue doesn't dry completely hard/rigid and so it can allow even standard thickness veneers to creep. I never recommend ordinary woodworking glue for veneer use.
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