Fan-Shaped Table Top Glue-Up

      A discussion of how wood movement may affect a table top assembled from thin pie-slices, assembled in a radial pattern. January 19, 2012

Question
I'm trying to research the best way to produce a radial lamination. I basically want to glue together a number of pie slices of 1 1/2" walnut and end up with a radial fan effect. This will become a table top. Final thickness: 1 1/4".

Forum Responses
(Laminate and Solid Surface Forum)
From contributor D:
This will not work with solid wood, since wood moves with changes in humidity. This is why this type of radial lamination is always done only with veneers. Beyond those two statements, things can get pretty complex, and a very good working knowledge of wood and its behavior is needed to go any further.



From the original questioner:
Okay, so it's a no go. What makes the radial lamination different from a butcher block? Both are composites of joined wood. Would this scheme work if there was a kind of cross support under the radial lamination to compensate for the bending due to humidity?


From contributor J:
I disagree with contributor D. It wouldn't work for a full circle, but for a quarter circle it would be fine. The top would change shape with humidity fluctuations, but it wouldn't self-destruct. This is basically a multi-stage gluing and clamping challenge.

Moisture from gluing the parts together could deform the thin ends of the wedges, so it might be necessary to glue on one piece, then machine the outer edge flat before adding the next piece. It'll be a tedious process, and ultimately you'll end up with a top that needs to be smoothed and flattened after all the gluing is over. I hope you're either proficient with hand planes or have access to a big wide-belt sander.



From the original questioner:
That is encouraging. I'm aware that all the things you say will have to happen: gluing pieces in pairs and build up to the full surface, plane it after. How would you join the pieces? Dowels? Biscuits? I've been told that a good way is to use a hardwood joint of a slightly less hard hardwood than walnut (the table top material). This will somehow compensate for swelling of the wood by the glue. Thoughts?


From contributor J:
The only reason to use dowels or biscuits in this situation is to help align the parts during glue-up. That may or may not be helpful, but it probably depends on the particular clamping arrangement you come up with. I can't comment on your hardwood joint idea because I don't understand what you mean.


From the original questioner:
Beyond alignment of parts, is there a method (biscuit or dowels) that will help to avoid splitting or warping more than others? Or are they all more or less the same?


From contributor J:
Wood movement is caused by changes in the moisture content of the wood. Dowels and biscuits have nothing to do with it. The wood should be properly dried before assembly. After that, the wood only moves with humidity changes. Keep in mind that this top will change shape considerably during normal seasonal humidity fluctuations, so make sure it's attached to the base in such a way that it can move without damaging anything.


From contributor G:
Why do wood floor medallions work at 5/8" thickness with grain moving in various directions? Many of these designs incorporate pie-shaped wedges revolving around a central axis...

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: Furniture

  • KnowledgeBase: Furniture: General


    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 © 1996-2016 - 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