Grit Selection for a Wide-Belt Sander

      Advice and experience about sandpaper and the sanding sequence. June 29, 2005

Question
We just got a new wide belt sander and are trying to figure out which grit to use. We ran a few test raised panel doors through, starting with 80, then 120 and finished up with 150. This did not give me the surface I was looking for. I am debating on starting with 100, then 150 and finishing with 180 or 220. I would like to hear what everybody else uses for grit sequence.

Forum Responses
I start sanding with 120 grit paper and carefully eliminate any working marks - from tooling, scrapers, etc. After this I wet the entire piece to raise the grain. When this is completely dry (generally a matter of an hour or so, although I often wait until the next day), I sand again with either 150 or 180 grit paper and wet the piece again. I then complete the sanding of the raw wood with 220 grit paper. This is a good point to do a very careful quality control inspection of the piece. Any glitches, nicks, scratches or the like must be fixed at this point.



A friend of mine has a timesaver double header. He swears by running 120 on the first head and 150 on the second. He says if he sands any finer than 150 it makes it harder to get the cross grain scratching out of woods like maple and cherry. If just sanding with the grain, I would probably stop at 180. With a lacquer finish, you won't see any difference by sanding finer than 180. With oil and wax finishes, there is luster to be gained going finer than 180.


We have a double head, but the sequence would be the same with a single also. We use 80, 120, 150, 180, a final pass with 180 with the platen down. We find 180 to leave a stain-ready finish with the grain.


Could you explain what a platen is? I'm not sure if our unit has one.


A platen is a 2-3" wide graphite covered piece of metal as wide as your drums are. It can be raised higher than the drums and not used or lowered for use. If your sander has only one lower drum, you do not have a platen. If it has two drums at the bottom, there should be a platen in between. Some sanders do not have a platen. It gives a smoother finish than a drum.


If you do not have a platen, try using 150 or 180 grit with a new sharp belt, a light pass, (removing only about .005") and a slow feed rate. This should help.


Thanks. Our new unit is a single belt.


Your sander with only a single belt should have a platen. If the belt makes a triangle when you install it, more than likely there is a platen in between the two bottom drums. At any rate, we go 80 grit always to remove any mill marks first. Seems like 120 usually leaves a few behind and our stain goes on blotchy as a result. Next... 120, wet, 180, 220, then lower platen with 220. This should leave crossgrains to a minimum and you usually only have to remove them farther if you are staining very dark.

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: 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