Walnut Glue-Up Adhesive Failure

      A woodworker gets advice about gluing up blanks for wood turning in a hot, dry shop. April 29, 2013

I live in south central Texas and my shop is a metal building that gets extremely hot in the daytime. I am using 8/4 black walnut boards - three boards to one post and gluing them with gorilla glue. The problem Iím having is the joints let loose after I turn the posts. I do not know what is happening. Is this due to the glue or the heat?

Forum Responses
(Adhesive Forum)
From contributor E:
I'm not sure you're using the right glue. Gorilla glue expands as it sets and is good for gap-filling. If you are clamping the boards together you might be squeezing most of the glue out and starving the joint. Have you thought about using a glue like Titebond?

From Jeff Pitcher, forum technical advisor:
I suspect that you have a few issues. First, you probably aren't getting the appropriate pressure if you're trying to glue 8/4 lumber. Next, it's probably very dry there which might not provide enough moisture to kick over the glue you're using. Finally, I'd suggest using a PVA glue as an alternative. The PUR is overkill for your project.

From contributor M:
Contributor E and Jeff make valid points.

Other things to look at:

What is moisture content of lumber?

Is stock flat and straight and freshly machined?

Do you have proper clamp pressure across the lamination?

Did you wait 24 hours after gluing to allow glue to get to full strength before machining?

When using Gorilla glue on kiln dried stock, we wiped both surfaces with a wet cloth prior to gluing. Titebond is probably a better choice if using for interior use.

Glue joint is typically stronger than wood. Is the failed joint only on the glue line or is there wood tearout as well?

From contributor R:
I'm not sure you can say that Gorilla glue is an efficient gap filler. It fills it with foam, but that has limited strength. Epoxy is the best adhesive that really retains strength in gaps. I agree with all the other thoughts.

From contributor C:
All are good points above. Of utmost importance is the flat fit of the planks. They must be jointed so there are no gaps prior to clamping. The slight ridges and lines from planer and jointer knife nicks must be scraped out so the glue has the best possible flat fitted surfaces to adhere together. Titebond II for dark woods will give excellent results. Flat relaxed fitted joints without the need for excessive clamp pressure will give the best long term results. You cannot hope for the glue to hold warps and gaps closed. They will be glue starved when you clamp things tight enough to close the gaps.

Would you like to add information to this article?
Interested in writing or submitting an article?
Have a question about this article?

Have you reviewed the related Knowledge Base areas below?
  • KnowledgeBase: Knowledge Base

  • KnowledgeBase: Adhesives, Gluing and Laminating

  • KnowledgeBase: Adhesives, Gluing and Laminating: Glues and Bonding Agents

    Would you like to add information to this article? ... Click Here

    If you have a question regarding a Knowledge Base article, your best chance at uncovering an answer is to search the entire Knowledge Base for related articles or to post your question at the appropriate WOODWEB Forum. Before posting your message, be sure to
    review our Forum Guidelines.

    Questions entered in the Knowledge Base Article comment form will not generate responses! A list of WOODWEB Forums can be found at WOODWEB's Site Map.

    When you post your question at the Forum, be sure to include references to the Knowledge Base article that inspired your question. The more information you provide with your question, the better your chances are of receiving responses.

    Return to beginning of article.

    Refer a Friend || Read This Important Information || Site Map || Privacy Policy || Site User Agreement

    Letters, questions or comments? E-Mail us and let us know what you think. Be sure to review our Frequently Asked Questions page.

    Contact us to discuss advertising or to report problems with this site.

    To report a problem, send an e-mail to our Webmaster

    Copyright © 1996-2021 - WOODWEB ® Inc.
    All rights reserved. No part of this publication may be reproduced in any manner without permission of the Editor.
    Review WOODWEB's Copyright Policy.

    The editors, writers, and staff at WOODWEB try to promote safe practices. What is safe for one woodworker under certain conditions may not be safe for others in different circumstances. Readers should undertake the use of materials and methods discussed at WOODWEB after considerate evaluation, and at their own risk.

    WOODWEB, Inc.
    335 Bedell Road
    Montrose, PA 18801

    Contact WOODWEB

  • WOODWEB - the leading resource for professional woodworkers

      Home » Knowledge Base » Knowledge Base Article