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Topic: Veneer Glue
Total Questions and Answers: 25
Additional Topics: Click Here
Last Update: 11/17/13

Veneer Glue Questions
  1. How do I know which glue to use?
  2. Can I veneer a panel if I don't have a vacuum press?
  3. What is a "cold press" glue and where can I learn more about veneer adhesives?
  4. What can I do to extend the open time on the cold press veneer glue?
  5. How much coverage will I get from a gallon of Better Bond™ cold press glue?
  6. What can be done to prevent the veneer from curling up as soon as it's laid onto the glue and substrate?
  7. What is PPR glue and why would I use it instead of regular veneer glue?
  8. How much coverage will I get from a 5 lb pail of the Ultra-Cat™ PPR veneer glue?
  9. Where can I learn more about Ultra-CAT™ PPR veneer glue?
  10. Can I use Better Bond™ veneer glue or Ultra-Cat™ for general purpose woodworking joints?
  11. How do I know how much veneer glue to apply?
  12. What is the difference between cure time, set time, flash time, etc?
  13. Can I use yellow glue for veneering?
  14. What is Heat Lock™?
  15. My friend uses contact cement for veneering with raw wood. Should I try it?
  16. What glue do I need if my veneered project will be outdoors?
  17. I'm using a paperbacked veneer but the veneer glue isn't giving me a good bond. Any suggestions?
  18. I want to adhere a piece of veneer to plexiglass, glass, or plastic. What adhesive should I use?
  19. What adhesive should I use to bond veneer to metal?
  20. What is the shelf-life of veneer glue?
  21. How will I know if my veneer glue is past its shelf life?
  22. Since there is no air movement inside the vacuum bag, does the Better Bond cold press glue actually cure?
  23. If my panel doesn't come out right, how do I remove a veneer from the substrate?
  24. Can I bond wood veneer to a solid wood substrate?
  25. Which of the colors tones of Better Bond veneer glue should I use if my veneer has light and dark colors in it?

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 cold press veneer glue 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.

Adhesive Name Type Application Method Veneer Type
Better Cold Press Veneer Glue™ Hard curing veneer adhesive Vacuum press or clamps and weights
Any raw wood or backed veneer
Ultra-Cat PPR Veneer Glue™ Hard curing veneer adhesive Vacuum press or clamps and weights Any raw wood or backed veneer
Heat Lock™ Iron-on adhesive Household clothes iron Any raw wood or backed veneer
Titan DX™ Contact cement Veneer scraper Backed veneer only
TC-20™ Copper adhesive Vacuum press or clamps and weights Copper veneer only
Flex-Pro™ (FSV) Similar to contact cement Pinch/Nip roller or veneer scraper Backed veneer only
Tolex Adhesive™ Similar to contact cement Varies Tolex only
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?Ironing Veneer with Heat Lock

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?

Veneer Glue GallonCold press glues are adhesives that do not require heat to bond and cure. This is the most common veneer adhesive type available. 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?

The Better Bond™ cold 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 cold press 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.

Blue Painters TapeI 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?

Plastic 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 Better Bond veneer glue or Ultra-Cat for general purpose woodworking joints?

Yes. I use the Better Bond 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?

Glue RollerThe key to applying glue is to put it on evenly. The rule of thumb is that the surface of the substrate should look evenly painted with veneer glue. 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 barely see the pencil mark on the substrate (through the adhesive), you have the right amount of glue. 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. You can also wipe the backer with lacquer thinner to chemically roughen its surface. Either method 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 oftern 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).

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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 Cold 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 cold press glue actually cure?

With a cold press glue, the bond is set inside the vacuum bag when the air inside the pores of the veneer and the substrate is displaced by the adhesive. This typically takes 45 to 60 minutes to occur. The curing process takes place outside of the bag after the glue has set. At this point, the panel is removed and allowed to cure outside of the bag. This concept applies to all standard non-catalized cold press veneer adhesives.

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 affect when mixed with water. The water does not need to evaporate to cure the adhesive. With this adhesive, the set and the curing takes 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 to remove 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, you'll find that quartersawn lumber is ideal since it has less seasonal movement than flat cut lumber. You'll also want to use a hard-setting PPR adhesive like Ultra-Cat. You'll need a vacuum press to clamp the veneer while the glue dries (4 to 6 hours).

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VG25: Which color/tone of Better Bond™ veneer glue should I use if my veneer has light and dark colors in it?

Better Bond veneer glue comes in light, medium, and dark tones. Generally speaking, it is preferable to go with a darker tone if you have both light and dark colors in your veneer.

If you are using a burl veneer that has some voids, 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. Doing this may accentuate some of the burl voids and overall that is the best look in my opinion.

Don't let worry about true bleed-through affect your choice in the veneer glue color. True bleed-through that comes through a clear (non-void) part of a 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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