JoeWoodworker
JoeWoodworker Veneer
The Official Website of this Non-Professional Woodworker ™

Part 1
Introduction

Welcome
Veneering Basics

14 Good Reasons
Vacuum Press Uses
Vacuum Press Options
Overview

Questions & Answers
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Part 2a (Option 1 of 2)
Project: V2 Venturi Press

About Project: V2
Parts List
Build the Manifold
Build the Reservoirs
Assemble the Venturi
Make the Carrier
Wire the Press
Testing and Adjusting
Mods and Options
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Part 2b (Option 2 of 2)
Project: EVS Pump Press

About Project: EVS
Parts List
Pump Selection
Build the Manifold
Build the Sub-Manifold
Build the Reservoirs
Make the Carrier
Final Assembly
Wire the Press
Testing and Adjusting
Mods and Options
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Part 3
Vacuum Bagging

Vacuum Bag Basics
Polyurethane vs. Vinyl
DIY Vacuum Bags (A)
DIY Vacuum Bags (B)
Connect the Bag
Bag Closures
Platens/Cauls
Breather Mesh
Maintenance
DIY Frame Press

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Part 4
Veneer Information

About Veneer
Veneering Myths
Backer Veneer

Veneer Glues
Veneering Tips
Substrate Materials
Flattening Veneers
A Sharp Veneer Saw
Jointing Veneers
Taping Veneers
Dealing with Defects
Curing Glued Panels
Veneering w/o Vacuum
Hammer Veneering
Iron-On Veneering
Veneer Storage
Amazing Bookmatches
Copper Veneer Guide
Paperbacked Veneer

Edgebanding Guide
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Part 5
Miscellaneous Info

Vacuum Forming
Vacuum Chucking
Vacuum Clamping
Vacuum Clamp Matrix
Vacuum Infusing
DIY Vacuum Manifold
JWW Visitors' Vacs
Veneer Quality
Veneering FAQ
Veneer Glue FAQ
The Vac FAQ
Copper Veneer FAQ
Downloads (PDF's)

VeneerSupplies.com

Vacuum Veneering - Tips, Tricks, and More

Paper Backed Veneer Guide

I wrote this guide for the customers at VeneerSupplies.com who have sent me so many excellent questions over the years about this type of veneer. It certainly has many uses in all kind of projects and its popularity is always growing. There are several types of backings that can be applied to a veneer but the most common are paper and wood (paperbacked veneer and 2-ply veneer). The questions and answers below should give you a solid foundation to begin any project with this type of material. Feel free to email me any other questions. I'll reply to your message and post the answers here.

What is paperbacked veneer?

Paperbacked veneer is exactly what the name implies. It's a real wood veneer permanently bonded to a paper backing. This backing is applied to keep intact the individual wood veneers used to make up the full width of the sheet. A four foot wide paperbacked veneer consists of multiple veneers glued together side by side. The backing also minimizes seasonal expansion and contraction of the wood caused by changes in ambient humidity.

The paper backing is generally available in a 10 and a 20 mil thickness. "Mil" or mil thickness is the common measurement of a coating. One mil equals 1/1000 of an inch. A quarter inch would be 250 mils. The backing is not removable.

A 10 mil backing is best for most projects. However, a 20 mil version is available for situations where the substrate is less than perfectly flat. In this case, the extra paper thickness allows the veneer maintain a more consistent look after application. Keep in mind that the 10 and 20 mil thickness is a reference to the thickness of the paper backing, not the veneer face.

What is wood-on-wood or 2-ply veneer?

Wood-on-wood, also known as "2-ply veneer" is two wood veneers permanently bonded together. The face veneer grain is perpendicular to the backer veneer which provides protection against bubbling which occurs when a veneer is improperly bonded to the substrate. This type of "crossband construction" allows the veneer to bend on moderate curves in the horizontal or vertical direction. The veneer used on the back side of a 2-ply veneer is often an imported hardwood of lesser value.

What is a PSA backed veneer?

Pressure sensitive adhesive (PSA) veneer is a type of paperbacked veneer that is a simple and easy alternative for applying veneer without the need for a liquid adhesive. Utilizing 3M™ adhesives, PSA veneer provides a permanent bond to any smooth substrate that is dry and free of dust and contaminants. PSA-backed veneer is the perfect choice for cabinet refacing, hi-fi speaker building, automotive dashboards and much more. It can be cut and trimmed with ordinary tools, such as scissors or a razor knife.

Keep in mind that PSA backed veneer is strong stuff and once it is applied, it can not be repositioned. More information about applying a PSA veneer can be found further in this article.

Where do I find paperbacked veneer?

VeneerSupplies.com is the companion website to the JoeWoodworker pages. You'll find over 3,000 veneer related products there. If you are looking specifically for paperbacked veneers, check out this page. Wood-on-wood or 2-ply veneers can be found here.

What is the thickness of the sheet?

Wood-on-Wood or 2-Ply Veneer - .035" or just over 1/32"
10 Mil Paperbacked Veneer - .020" or 1/50"
20 Mil Paperbacked Veneer - .035" or just over 1/32"
Veneer Edgebanding - .030" or just under 1/32"

All thicknesses may vary by .005 inch. These dimensions are based on the veneer and edgebanding offered at VeneerSupplies.com.

What is the thickness of the actual veneer face on the sheet?

Generally speaking, the actual wood part of a paperbacked veneer is .015" but the thickness can vary based on the amount of finish sanding done at the factory. The factory sands each veneer sheet until it is perfectly smooth.

Why would someone use a 20 mil veneer instead of a 10 mil veneer?

A 10 mil backed veneer is used when the substrate is smooth and flat. Some cabinetmakers will only use 10 mil veneer on vertical surfaces and 20 mil on horizontal parts such as desk and table tops.

Regardless of the substrate position, a 20 mil backed veneer or 2 ply veneer should be used if the substrate is not smooth since the thicker backer will help hide some substrate imperfections. Additionally, a 20 mil veneer is often used on curved projects.

Keep in mind that the wood veneer face is the same thickness regardless of the backer. The 10 or 20 mil specification refers only to the thickness of the paper backing.

How is a backed veneer measured?

The standard size for most backed veneer is 4' x 8'. The 4 foot measurement is the width of the sheet across the grain. The 8 foot measurement is the length of the sheet parallel to the grain. Most vendors oversize the sheets by ¼" on both the length and the width.

Where can I get samples?

Veneer Sample BookVeneerSupplies.com has a sample book containing 41 samples of backed veneer. The book contains samples of ash, bamboo, birch, cherry, fir, hickory, lacewood, mahogany, maple, red oak, white oak, pine, rosewood, sapele, teak, walnut, wenge, and zebrawood. Samples of PSA, 2-ply, 10 mil and 20 mil veneers are also included. Click here for more information.

What material can paperbacked veneers be applied to?

The part of the project that the veneer is applied to is called the substrate. Here is a list of substrates and adhesive information. Keep in mind that the substrate must be smooth, clean, dry, and acclimatized prior to application of the veneer. Note that this chart applies to paperbacked veneers only.

More information about various veneering adhesives can be found here.

Substrate
Contact Cement
Heat Lock™
Veneer Glue  
Cold Press
Veneer Glue
PSA
MDF
Excellent
Excellent (1)
Excellent (1)
Acceptable (4)
Particle Board
Excellent
Excellent (1)
Excellent (1)
Excellent
Plywood
Excellent 
Excellent
Excellent
Excellent
Solid Wood
Very Good
Excellent
Excellent
Poor
Masonite™
Poor
Poor
Poor
Acceptable
Melamine
Acceptable (2)
Poor
Poor
Acceptable (2)
Plastic Laminate
Acceptable (2)
Poor
Poor
Acceptable (2)
Drywall
Excellent (3)
Excellent (3)
Excellent (3)
Excellent (3)

Notes:
1 - For cold press veneer glue and Heat Lock, sand the back side of the veneer and the face of the substrate with 150 grit sandpaper. This will make the surfaces more por
ous and allow the adhesive to bond the materials with exceptional durability.

2 - With adequate ventilation or a NIOSH approved respirator, melamine and plastic surfaces must be heavily sanded with 80 paper and wiped with a tack cloth. The surface must then be cleaned with denatured alcohol. The veneer should be applied within 45 minutes of cleaning and permanently "seated" using a veneer scraper.

3 - VeneerSupplies.com does not recommend application of paperbacked veneer directly to drywall. Instead, we recommend covering the drywall with ½" MDF using construction adhesive. The veneer can then be applied to the MDF.

4 - It is always a good idea to coat MDF with shellac first and sand it lightly when dry. Then apply the PSA veneer.

Can I use paperbacked veneer on exterior projects?

Paperbacked veneer can be used with projects that will be exposed to weather. However, we have found that epoxy is the only adhesive that will withstand the outdoor environment.

How do I apply a backed veneer?

Allow the veneer and substrate to acclimate in the same work area for 48 hours. This will ensure that the moisture content in the veneer and substrate has equalized.

Begin the acclimation process by unrolling the veneer and laying it flat. The ideal shop environment is relative humidity of 35% and a temperature of 70° to 80°F. It may be necessary to place weights on the ends of the veneer to keep it flat while it acclimates and losses its "rolled memory".

Contact Cement

Veneer ScraperOne of the most overlooked aspects in contact cement veneering is adhesive coverage, yet it is the single most important part of this veneering method. It is critical that all areas of the veneer and substrate are coated with adhesive. Any areas left dry may result in the veneer bubbling after application. For solvent-based contact cement, it is a good idea to apply two coats (per side) with a glue roller. Water-based contact cement generally requires only one coat per side.

If you are using contact cement you'll only need a veneer scraper to apply the veneer. More information about the veneer scraper can be found on this page. A handheld roller is not suitable for applying veneer. It simply does not concentrate enough pressure over the contact surface to create a durable bond. A veneer scraper is a must! Be sure to scrape the entire veneer surface (scraping with the grain) to achieve a maximum strength bond. Most manufacturers recommend scraping the surface twice. Always use the centerline technique (figure 2) when using the scraper tool.


Figure 1: Scraping the veneer is critical to success.

The Centerline Technique
Figure 2: The centerline technique seats the veneer properly to the substrate. Follow this pattern with the scraper to avoid over-stretching the veneer.

PSA Veneer
Veneers with a pressure sensitive adhesive backing require a veneer scraper to seat the adhesive and veneer firmly to the substrate. More information about the veneer scraper can be found on this page. A handheld roller is not suitable for applying PSA veneer. It simply does not concentrate enough pressure over the contact surface to create a durable bond. A veneer scraper is a must! Be sure to scrape the entire surface of the veneer using the centerline technique to achieve a maximum strength bond. Most manufacturers recommend scraping the surface twice.
Always use the centerline technique when using the scraper tool.

Keep in mind that PSA adhesives bond instantly on contact. Be certain that you have the veneer positioned correctly before applying the veneer. After the veneer has been scraped down, no additional clamping is necessary.

Heat Lock Iron-On Veneer GlueIron-On Veneering with Heat Lock™ Glue
Heat Lock
™ is an iron-on adhesive that can be successfully used with paperbacked veneer but is difficult to use with 2-ply veneer. Learn more about this superb adhesive at this link.

Cold Press Veneer Glue
If you have a vacuum press and want the ultimate bond strength, consider applying the backed veneer with Better Bond™ cold press veneer adhesive.

Is the veneer sheet a single piece of wood?

No. Each sheet is made up of several veneers, called faces, laid side by side with opposite sides showing. This is called bookmatching. The individual veneers used to make sheet of backed veneer can range from 3" to 8" in width. With the exception of burls, the face veneers are 8 foot in length on a 4' x 8' sheet.

Are there visible lines in between each sheet in the backed veneer?

The veneers used to make a 4 x 8 sheet are laid up in the sequence from which they were sliced from the tree. This creates a visually pleasing result. If you look close enough you might be able to see the joint line. The quality of the seam between each veneer is what defines the visibility of the joint. Our veneers our jointed with state of the art machinery and are inspected by a trained QA staff member before shipping out. Only flawless veneers are shipped to customers.

Is the paper or wood backing visible at the edges of a backed veneer?

After the veneer has been stained and finished, the backer is barely visible on most species. Below is a picture of my desktop with a paper-backed cherry veneer used on top and a cherry hardwood edge. The line between the backing and the face veneer is almost impossible to see.


Click to Enlarge

How is the sheet measured?

The 4 foot measurement is the cross-grain width and the 8 foot measurement is the long grain length.

Is a backed veneer better than raw wood veneer?

Advantages

  • If you have a large project to veneer, you'll find that a backed veneer is easier to work with because it is available in large sheets. From a production standpoint, a backed veneer is unbeatable.
  • Backed veneers generally stay flat while being stored. They usually will not buckle unless the humidity levels are extreme. The only notable exception is maple which has a tendency to curl a bit in storage if it is not kept under a weighted board.
  • Adhesive bleed-through in a backed veneer is highly unlikely.

Disadvantages

  • Backed veneers are usually more expensive per square foot than raw wood veneers.
  • Burl veneers with a paper or wood backing are shockingly expensive. A raw wood burl is often 1/4 of the price.
  • The wood face on a backed veneer is thinner than standard raw wood veneer which makes it easier to sand through.
What is barber pole effect?

Barber Pole EfffectWhen veneer is sliced, a distortion of the grain occurs. The knife blade, as it hits the wood, creates a "loose" side where the cells have been opened up by the blade and a "tight" side. Because the "tight" and "loose" faces alternate in adjacent pieces of veneer in book matching, they may accept stain differently. This may result in a noticeable color variation called barber poling. Slip matching (all veneer faces are in the same direction) is often used in quartersawn and rift cut veneer to minimize the barber pole effect. This is an available option at VeneerSupplies.com.

Veneer Slip Matching

Can a backed veneer be treated with veneer softener?

Veneer SoftenerSuper-Soft Veneer Softener can be lightly applied to paperbacked veneer. The preferred method is to dampen a soft cloth or paper towel with softener and pad it on to the veneer in light, overlapping motion. It is not a good idea to saturate the veneer to the point at which the backing is wet. Since the face (the wood part) of the paperback veneer is very thin, a light coat of softener is all that is needed to give the veneer the extra flexibility that is sometimes needed on tight curves.

What do I do with the edges of the substrate?

Veneer EdgebandingYou can apply edgebanding to the sides of the substrate. Edgebanding is available in several species. If you can not find edgebanding in the species required, simply cut 1" wide strips from the veneer used for the main project and apply it to the edge of the substrate with Heat Lock or contact cement. Learn more about edgebanding by clicking here.

What is sequence matching?

Sequence matching is the process in which the factory ships the customer sheets of veneer that reasonably match each other in terms of color and grain pattern. This option is great for large projects where consistency is critical to success.

Does a backed veneer require sanding?

The veneer is pre-sanded to 150 grit at the factory. However, many users find that they get a more even stain color if they sand the veneer one grit grade higher than the rest the project. So if you sanded the solid wood parts of a project with 150 grit sandpaper, you might consider sanding the veneered parts with 180 grit.

How do I cut and trim a backed veneer?

Paperbacked veneer can be cut to size with scissors or a razor knife. Two-ply veneer can be cut with a hand saw. Trimming a veneered panel is most commonly accomplished with a flush-trimming ball bearing piloted router bit. You can also trim the veneered panel on a table saw with an 80-tooth saw blade.

How is a backed veneer shipped?

It is rolled up in a box and shipped via FedEx or USPS (depending on destination). The factory can usually get 5 to 7 paperbacked veneers in a 10" x 10" x 50" box. Two-ply veneers ship in a larger box because it can not be rolled as tightly as a paperbacked veneer. This box is usually 14" x 14" x 50" and is considered oversized by the carriers so the shipping rates are a bit higher.

If you order from VeneerSupplies.com...
Orders containing more than 4 sheets of paperbacked or 2 sheets of 2-ply veneer are occasionally calculated incorrectly by the website software. We refund any significant difference between what the website charges and the actual shipping charge after we are billed by the manufacturer for your order.

Is backed veneer bendable?

Bendable VeneerMost paperbacked veneer species can take up to a 1" radius bend along the length of the grain and 5" radius bend across the grain. A light coat of veneer softener can increase the flexibility of the veneer and prevent splitting on tighter bends. In fact, I have achieved a 1/4" radius on the grain length when I treated the veneer with softener.

Most 2-ply veneers can accept a bend up to 5" along the length of the grain and 8" across the grain. Veneer softener is generally not effective on 2-ply veneers.

If you choose to apply a paperbacked veneer over bendable plywood, we recommend first applying 1/8" MDF to the plywood to add strength and rigidity.

Are the woods used on backed veneers graded?

Yes. When buying a backed veneer, be sure to specify a grade of AA or better. Anything less will have mineral streaks, bark, sapwood, or other defects. If the vendor can not tell you the grade, its best to assume the worst.

How do I stain and finish a veneered project?

Since it is a real wood product, it stains just like a piece of solid lumber. However, many users find that they get a more even stain color if they sand the veneer one grit grade higher than the rest the project. So if you sanded the solid wood parts of a project with 150 grit sandpaper, you might consider sanding the veneered parts with 180 grit to get optimum color matching.

It is best to apply a protective finish to the veneer when the ambient humidity is 55% or less. Do not use heavy coats of finish. Instead build up multiple smaller coats which dry faster and trap less solvent under the finish. Additionally most catalyzed finishes will "check" or crack if applied too thick.

Water based stains and top coats are not considered ideal choices paperbacked veneer. If you must use this type of finish, be sure to apply a vinyl or acrylic sanding sealer to the veneered panel before staining and finishing.

This information applies to all backed veneers... 2-ply, paperbacked, and PSA.

How do I test my veneer to make sure it is bonded properly?

Since there are many combinations of veneer, substrates, adhesives, finishes, and environmental conditions, we highly recommend testing a small piece of veneer with your application and finishing process before you begin the main veneer work.

Be certain to check for bubbles before applying your finish. If bubbles are present, this may be the only time to address these issues. The best way to check for bubbles is to place a powerful light (such as a halogen work lamp) beside the veneered panel and no more than 15 degrees above it. Look for peaks and shadows across the panel. Most bubbles can be easily repaired.

PSA and Contact cement: Place a piece of cotton or flannel cloth over the bubble and gently heat the bubble with a clothes iron. The heat will reactivate most contact cements. Keep the iron in motion to prevent overheating the veneer. Once the veneer is adequately heated, scrape the bubble again until the area cools down.

Heat Lock: Within 24 hours of application Heat Lock can be reactivated. Place a piece of cotton or flannel cloth over the bubble and gently heat the bubble with a clothes iron. Keep the iron in motion to prevent overheating the veneer. Once the veneer is adequately heated, scrape the bubble with a veneer scraper or block of softwood until the area cools down.

Cold Press Veneer Glue: When high quality cold press veneer glue is used with a vacuum press, bubbles are generally not a problem. In the event that a bubble does show, the ironing method described above will usually fix the issue.

Do I have to use a balance/backer veneer ?

I always use a paper backed veneer on the back side of my panels if the face side uses a paper backed veneer. Others say they never use a backer/balance veneer and haven't had any warping problems. I think this largely depends on several factors.

  • Attachment Method - If you're plan is to fasten the panel to a structurally sound surface, you may be able to mechanically force the veneered panel to lay flat.
     
  • Substrate Thickness - a thicker substrate will not warp as much as a thinner one. The downside is that a thicker substrate may be harder to force to lay flat.
     
  • Adhesive Type - Water based adhesives can cause the veneer to expand slightly. The veneer will shrink when the moisture evaporates from the panel and this can cause warping.

The best option may be to use a water based contact cement and back the panel with cheaper paper backed veneer. This is what I do and I never have to worry about warping.

 

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The Vac FAQ
Heat Lock Veneer Glue