Holding Veneer Flat on a CNC Table

      A CNC operator finds that veneer tends to "bubble up" off the vacuum spoilboard in random spots. Here, he gets advice on holding the material down so he can cut inlay pieces out of it. June 30, 2007

We're trying to cut inlays from veneer sheets on a flat table CNC. The inlays we're cutting are about 3" square. The veneer sheets can be anywhere from 3' square to 4' x 8'. We're using a small cone tool with a 30 degree included angle. We're having a problem holding the veneer on the vacuum table. The spoilboard is freshly flycut. The veneer will bubble up in some random areas. Any ideas on how to hold the sheets flat on the table?

Forum Responses
(CNC Forum)
From contributor C:
Lay a sheet of a thin non-porous material over the veneer and cut through it. Let us know how this works (or any other idea that works).

From the original questioner:
Thanks. We'll try some 6 mil plastic and let you know.

From contributor R:
I have done this before by lightly contacting the veneer to a sheet of MDF. Then you can carefully peel them off.

From contributor B:
3M makes a product called repositionable 75. Kind of like the glue on sticky notes. I've used it on other projects, but never on the router.

From contributor T:
Why use a V tool? I would think a small diameter spiral would work. Perhaps the smallest downcut you can get. Also... you could try the thinnest spoilboard you could dare use. Would improve hold down.

From contributor A:
Use an 1/8" downward spiral cutter to cut the veneer. The 3M spray adhesive will hold the material down with no problems.

From contributor G:
Do not use 6 mil plastic! It will wrap around the bit after some of it is loose. Try sign-makers masking paper, low tack. It will not have this problem! Having said that, using the 3m low tack spray glue (Office Depot will have in the art supply section) will probably work fine for holding the small pieces.

From contributor P:
We [Benz, Inc.] make an aggregate tool which we refer to as a vertical trimming unit, but it is more commonly known as a floating head. It looks very much like a hand router and fits into the motor spindle on your machine. The cutting tool is set to be exposed from the bottom of the unit to the depth of cut you are looking for. The bottom of the unit has a non-marking material (Teflon) which travels across the material you are cutting. It is designed to trace the surface and move up and down to accommodate any tolerance in the surface of the work piece you are machining. In your case, the floating shoe would act as a hold-down device keeping the veneer flat against the spoil board. Depending on how much of this kind of cutting you do, this may be a good solution.

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: Computerization

  • KnowledgeBase: Computerization: CNC Machinery and Techniques

  • KnowledgeBase: Veneer

  • KnowledgeBase: Veneer: Machinery

    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