Gluing and Clamping Woodworking Tips

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Here you will find a list of 28 helpful tips for using glues and clamps

Definitions:
Glue - A generic term used for adhesives.
Clamps - Devices used to hold lumber together for the purpose of gluing or securing with fasteners.

  1. When gluing a number of boards edge to edge, alternate the growth rings of each board in order to prevent cupping.

  2. When gluing oily woods, such as teak, use acetone to clean the oil from the glue surface.  After it has dried completely, the wood can be glued and clamped.

  3. Blockboard is not suitable for outdoor use because the adhesive used is typically for indoor applications.

  4. Avoid end joint gluing if possible.  End joints are very weak, no matter what type of glue is used.  If end jointing is necessary, consider doweling them or using end lap joints.  These alternatives will help strengthen the joint.   

  5. If gluing end grain joints is necessary, apply a double coat of glue.  End grain acts like a sponge and quickly absorbs the glue.  Allow the first coat to soak in for a minute and then apply the second coat to improve the joint strength.

  6. When joining wide boards with glue, use blue painters tape on the steel bar clamps to prevent the glue from reacting with the metal, causing black stain marks in the wood.

  7. When clamping wide surfaces, such as table tops with bar clamps, it is recommended to position the clamps on the top as well as on the bottom of the boards.  This will ensure sufficient and uniform pressure.

  8. Gluing together a large number of parts at the same time can be unwieldy, such as hexagon or octagon projects.  A solution to this problem is to first apply glue to the edges and then use blue painters tape to temporarily hold the project together until the clamps are positioned.

  9. Another clamping technique when attempting to clamp a project with numerous angles, such as an octagon, is to wrap an elastic band around the project and secure the end of the elastic with a hand screw clamp.

  10. Polyvinyl acetate (PVA) glue is not very water resistant, and should be used for indoor purposes only.

  11. In order to determine the proper amount of glue to apply, use the following rule-of-thumb:  If the glue runs or drips excessively, when the clamp pressure is applied, it is too much, and if there is no squeeze out it is too little.

  12. When gluing together a large number of boards, such as cutting boards or butcher block projects, divide the projects into thirds.  Apply glue to the first third and clamp them.  Repeat this process until the three sections are clamped.  When the glue is set, clamp the three sections together.  This technique will prevent the glue from setting up prematurely and assure proper adhesion.

  13. Appling glue with a roller will speed up the process and insure that the glue is spread evenly.

  14. Don’t use casein glue with white oak.  The acid content of the wood will react with the glue and result in a weak joint.

  15. Do not use plastic resin glue with oily wood species.  Plastic resin glues are water based and will be repelled by the oil in the wood.

  16. Always clean up the glue joints soon after clamping the wood.  Use a dry paper towel to clean up the greatest amount of excess glue.  Then use a wet paper towel or rag to remove the remainder of the glue to prevent it from soaking into the pores.

  17. A way to prevent glue from spreading onto the wood surfaces is to tape the glue joint surfaces with blue painters tape prior to applying the glue.  When the clamp pressure is applied, the excess glue will squeezed onto the tape instead of the lumber.

  18. Excess glue that has soaked into the wood around the glue joint will prevent stain from properly being absorbed.  This will create and uneven stain job, which will result in an undesirable finished appearance.

  19. When gluing boards, always attempt to match the grain patterns and color in order to achieve a uniform appearance.

  20. Resorcinol-formaldehyde resin glue is water resistant, and is recommended for outdoor and under water projects.

  21. It is important to apply even clamping pressure along the glue joint to insure a superior adhesion.  If long boards are glued, a series of clamps may be necessary.

  22. Use polyurethane type glue when joining two different materials, because polyurethane glue tends to adhere to most all materials.  It is activated by moisture, so spray a little water on one of the surfaces in order to speed up the curing process.

  23. A band clamp is a good choice for clamping mitered parts.

  24. When using C-clamps use scrap wood blocks between the lumber and the clamps to prevent denting.

  25. When gluing and clamping a large number of boards, place waxed paper with boards, perpendicular to the project at each end.  The waxed paper and perpendicular boards should be placed on the bottom and the top near each end, and then lightly clamped to keep the surface of the project flush.  The waxed paper will prevent the boards from adhering to the project when it is clamped together.

  26. Epoxy resin glue is ideal for bonding most dissimilar materials.

  27. Aliphatic resin and plastic resin glues are considered all-purpose glues, and are suitable for most wood projects.

  28. A way to perfectly align veneer is to first apply contact cement to both surfaces and allow the cement to set.  Next place a sheet of wax paper over one surface, leaving a short piece exposed.  Finally, align the veneer and slip out the wax paper.