Carbide Tipped Versus Solid Carbide Knives

      The comparison between high-speed-steel, carbide-tipped, and solid-carbide knives depends in part on what material you're machining. August 12, 2007

I am currently running HSS planer knives in my planer. I am considering carbide tipped or solid carbide. Can someone help me out with information?

Forum Responses
(Architectural Woodworking Forum)
From contributor R:
The type of material can be a big factor in your knife type. HSS knives will give you a cleaner cut because you can get a sharper edge. Don't get me wrong - carbide tipped or solid carbide are very sharp, but not quite the same.

The big factor in the carbide tipped and solid carbide is the life. You will increase your run time between sharpenings a great deal, therefore less down time and less setup time is required.

From contributor A:
The carbide used in inlayed tipped knives is usually not as long lasting as solid carbide knives because the harder carbides will crack when they are brazed into the HSS backer. Carbide tipped can still give very good results, though, and they are generally a lot less expensive that solid. Remember, different wood species do better with different tooling. What type of lumber are you mostly planning on planing and how much?

From Professor Gene Wengert, Sawing and Drying Forum technical advisor:
A couple rules of thumb... The softer the wood, the more HSS will give a clean cut. Carbide fuzzes softer woods. The denser and knottier the wood, the more chance that you might hit a dry knot and fracture the carbide. Sharpening is more technical with carbide. In a planer, jointing is not really sharpening carbide. Carbide will outlast HSS by at least 30x, unless you hit something harder than wood.

Are you planing rough lumber that has been air dried? If so, a segmented knife is best, as you only damage one small segment when you hit a small stone, etc. Because carbide is brittle, care must be used to avoid damaging the carbide edge (hitting, dropping, etc.). Carbide gets dull and must be sharpened. Oftentimes I see carbide used too long between sharpenings. When you have the need for sharp edges in a profile (not a question when you are using a planer), HSS may do a better job.

From contributor S:
Some personal experience, for what it's worth. I am not a production shop - mostly custom furniture and boat work. I don't joint/plane a ton of lumber, but a fairly high percentage of what I do is teak. And teak is murderous on HSS. I put carbide edged knives in both my jointer (Jet 6") and planer (Delta 15"). The jointer knives were approximately C$60 each (times 3) and the planer knives were C$130 each (times 3). This is not trivial... and solid carbide was substantially more expensive. I went with tipped knives because of expense, and the fact that solid are more brittle.

The finish from the carbide knives is not as good as HSS, no question. However, my theory was, and has proven true, that I never need a finished surface right out of the machine. A jointed edge gets glued (typically) or finish sanded anyway. And a jointed face ends up going through the planer, and again, the planed faces end up getting sanded anyway. And the difference in sanding time is negligible. But the kicker was/is, that even though the carbide is not as smooth a finish, if you're running teak, by the time you have pushed a couple of sticks through it, the HSS has dulled to the point where it is no better than the carbide. And finally, I hate changing knives. I did not know about Shelix heads when I made my decision.

Having said all that, even though I'm glad I've got carbide instead of the stock knives, if I was going to do it again I would either look more closely at:
1) A Terminus or some such head that is very simple and easy to change knives (and the knives are not all that expensive). Then you get the advantage of a HSS cut and finish.
2) Shelix heads. This is most likely.

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: Solid Wood Machining

  • KnowledgeBase: Solid Wood Machining: Tooling

    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 © 1996-2019 - 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