Where can I learn more about breather mesh?
I've written a short article about breather mesh on the JoeWoodworker website.

Do I need several sizes of mesh for each size project I put in my vacuum bag?
Most people have one piece of mesh that matches the size of their vacuum bag. This way, no matter what size your project is, if it will fit in the bag then the mesh will fit too.

Can the mesh be cut?
Yes. The mesh can be trimmed to size with a pair of scissors.

Do I cut the mesh to fit my project or to fit my vacuum bag?
Generally speaking it is best to cut the mesh to fit your vacuum bag if the veneer panels you create will be flat. For curved projects, custom-sized breather mesh is often required.

Is a top platen board needed when using breather mesh?
If the veneer is flat, the mesh will press the veneer against the substrate wiithout the need for a top platen. If the veneer is not very flat, a top platen (with breather mesh over it) can often help put more "pressure" onto it and force it flat.

Does the bottom platen board require air channels/grooves?
If the bag's vacuum port is on top, there is no need for grooves in the bottom platen. There simply isn't enough free air between the bottom platen and the bottom of the bag for grooves to make a difference.

What should I use for a platen board?
You'll find that 3/4" thick melamine board is excellent because most veneer adhesives will not stick to it. You can find this material at large hardware stores like Home Depot and Lowes. It is usually in or near the plywood aisle.

How do I get the mesh into a long vacuum bag?
There are two common ways get the end of the mesh into the far end of the bag. One option is to insert the mesh (after the platen is set in the bag) using a broom handle or dowel with duct tape wrapped sticky-side-out around the end. Use the stickiness to grip the mesh so it can be pushed to the end of the platen board.

A more permanent option is to use #6 x 3/4" screws with small washers to secure the mesh to the leading edge of the 3/4" thick platen board. The screws/washers should be 6" to 8" apart. This allows the mesh to go into the bag as the platen board is inserted.

Start by cutting the mesh to the exact width of the platen. Then line up the side edge of the mesh with side of the platen board. Use masking tape to temporarily hold it in place on the left and right side of the platen. Leave about 3/4" of overhang at the leading/forward edge of the platen. Then fold the mesh over the leading edge and use the screws/washers to secure the mesh to the edge of the platen.

How many times can the breather mesh be used?
The mesh should last for a very long time. I suspect that the mesh piece that I use in my shop has been used for more than 100 panels.

Will the veneer glue get trapped in the mesh and ruin it?
Glue that squeezes out from under the veneer will stick to the mesh. Larger blobs of regular veneer glue will typically release from the mesh if the material is flexed a bit. Small blobs will also release but I don't bother to remove them since they do not reduce the effectiveness of the mesh.

Can I use window screen material instead of breather mesh?
Yes and no. Window screen material can create a pathway for the flow of vacuum and several users have sent messages saying they had no issues other than a moderate increase in the amount of time it took to draw full vacuum in the bag. It is important to know that a veneer that is not completely flat is not likely to flatten under window screen material; you can get lumps in the finished panel. The other issue is that any adhesive that bleeds through the veneer will smear back onto the surface of the panel. Our breather mesh has a much wider/open weave than screen material so glue that comes through the veneer (especially for porous species and burls) beads up and can be easily scraped off. I've also found that breather mesh is much easier to slide into the vacuum bag than screen material.

Will I get excessive bleed-through with mesh?
Some bleed-through is a good thing. Small beads of glue that come through the veneer are a sign that the right amount of glue was applied to the substrate. Let those beads dry and then use a cabinet scraper (aka card scraper) to easily remove them. Porous species like walnut, mahogany, and oak will allow more bleed-through to occur. Other species such as maple and beech typically do not bleed-through.

If too much glue or too much vacuum (more than 21" Hg) is applied to the project, you might get quite a bit of bleed-through. This is not a fault with the mesh, and a panel with too much glue is likely to cause issues even if mesh is not used. Reduce the amount of glue and if necessary, decrease the vacuum level on your bag to minimize bleed-through issues.

Why is the mesh not sold in a 54" width to match the size of the larger vacuum bags?
The manufacturer does not yet have the capacity to build the mesh any wider than 48 inches. Each time I order rolls of mesh, they tell me that they are continuing to add machinery and technology to improve on this width but I've not yet seen any results.

Will the breather mesh protect the vacuum bag from sharp corners on the veneer panel?
Generally speaking, yes; the mesh offers some degree of protection. The amount of protection depends on the angle of the corner, the age of the bag, and amount of vacuum being applied.

What if my project is wider than 48"?
Simply order enough mesh for two side by side pieces that you can lay inside the bag. Some users have reported success by joining the two pieces with duct tape.

From what material is the mesh made?
Our mesh is currently made from polypropylene.

Why is this stuff so expensive?
It is my opinion that the cause is simply corporate greed. The only manufacturers of this material in the US have all been bought up by a giant corporation. Since they have monopolized the supply of this product, they have raised the price well beyond what I could have ever imagined.

How do I prevent the mesh from imprinting the veneer?
There are only two causes of markings left by breather mesh and both are easily preventable. If there is too much glue on the substrate, the veneer will float on the adhesive surface and the mesh will create quilt-like markings. Obviously the key is to use less glue.

The rule of thumb is that the surface of the substrate should look evenly painted with veneer glue. It should not be dripping wet. A good test 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.

The second cause is too much vacuum. It's a good idea to lower the vacuum level to 17" Hg on softer woods like walnut and redwood to prevent markings from the mesh.

Will epoxy stick to the breather mesh?
Yes.

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