Page 2 of 2 FirstFirst 12
Results 16 to 27 of 27

Thread: Must I laminate both sides of everything to avoid warping?

  1. #16
    Join Date
    Apr 2007
    Location
    Columbus, Ohio, USA
    Posts
    3,441
    Quote Originally Posted by Bill Orbine View Post
    Attachment 179498 I see too much of that in the top drawing and I think the lower drawing is a better way to go!
    A 9/16" height rabbit on the oak, a 5/8" rabbit on the MDF (both 1/2" left to right), should leave the oak 1/16" proud. I can then use trim bit to bring the oak to exactly the same height as the MDF and apply the top laminate.

  2. #17
    Join Date
    Apr 2007
    Location
    Columbus, Ohio, USA
    Posts
    3,441
    Good.... Easy to laminate both sides of the MDF. I did not want to laminate the bottom of the Oak. Do not mind a bit of poly though.

  3. #18
    Join Date
    Dec 2006
    Location
    Madison, Wisconsin
    Posts
    489
    Quote Originally Posted by Scott T Smith View Post
    Bob, let's say that there is a situation where you cannot use the same veneers on both sides (such as when working with a very costly burled veneer or a rare material), what rules should one follow when choosing a veneer for the 'back' side?

    I presume that rule #1 would be to use a veneer with the same thickness as the display side, and rule #2 would be to use a material with a similar specific gravity? Or are there different rules that should be followed?
    Scott,
    You are correct. The best bet would be to use the same specie and thickness. I would suggest a balance design (same number/orientation of veneers top and bottom from the neutral axis (center of section)) and if you use a walnut burl on top, use a walnut veneer on the bottom. Where you can't use the same specie, I suggest trying to match both SG and shrinkage characteristics, if possible. Also, I would also match grain orientation top and bottom (obviously there is no orientation to match with burl).

    Our Wood Handbook Tables 4.3 and 4.4 list the shrinkage values for various species and Tables 5.3-5.5 provide SG values. See www.fpl.fs.fed.us for download. Note that cross grain in peeled veneer is the tangential direction (greatest shrinkage in tables). Depending on how sliced, much veneer is akin to lumber and will be cut across both the radial and tangential directions (I would use an average of the radial and tangential values from the tables in this case). If the veneer is radially sliced, then you would use the radial value.
    Hope this helps. Cheers, bob
    Last edited by Chris Padilla; 01-25-2011 at 3:36 PM.

  4. #19
    Join Date
    Oct 2007
    Location
    New Hill, NC
    Posts
    2,568
    Bob, that's great info - thanks much.

    I manufacture a sawn veneer, so the data is very applicable.

    Regards,

    Scott

  5. #20
    Join Date
    Jan 2010
    Location
    Tampa Bay, FL
    Posts
    3,895
    Can you laminate one side of MDF and seal the other side (and edges) with shellac and avoid problems, or is laminating both sides necessary.

  6. #21
    Join Date
    Feb 2008
    Location
    Topeka, Kansas
    Posts
    311
    most prefab kitchen counters are particle board with laminate on only one side and they stay flat...
    If you don't make mistakes, you don't learn.

    -- Sam Maloof

  7. #22
    Join Date
    Sep 2009
    Location
    Three Rivers, Central Oregon
    Posts
    2,340
    For $150: http://www.woodpeck.com/rt2432p.html
    Attached Images Attached Images
    Scott Vroom

    I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.

  8. #23
    If you make the edge of the oak flush with the laminate (not under it) it will help protect the edge of the laminate from de-laminating or breakage from use. I like the idea of a torsion box but maybe a bit much but hey never enough right. Another thought which I am about to embark on (because mine warped, I did not seal or cover) is to mount the bottom to 2 rails made of angle iron. I actually just checked H. Depot for some stock and they had some steel with pre-drilled holes along the entire length which might be nice for hanging tools and save drilling. These pieces were very strong I tried to bend them and they did not budge and were very straight. Did you say 1/8 inch laminate? I have never seen it that thick.

  9. #24
    Quote Originally Posted by Mike Gager View Post
    most prefab kitchen counters are particle board with laminate on only one side and they stay flat...
    no they don't they appear to be flat and stay that way if they stay dry and are screwed down well enough but they are not flat like you want a router table top to be flat also particle board in that application is "good enough" for the majority of the construction industry you can also use MDF for countertops the same way also not as flat as you want a router table top

    if you want laminated panels to stay flat and the back /bottom isn't visible then its common practice to put backer laminate (brown or black and thinner / cheaper than the laminet you want to look at on the top/outside) on those surfaces (look at laminated table tops for example)

    as to the OP's question, the best practice for what you are wanting to do would be to laminate top and bottom of the MDF and poly the exposed oak
    and seal the edge of the mdf where the cutout for the router is just don't soak that mdf edge or it will swell and mess up your top i often seal those edges with contact cement put on with a small roller for smoothness

    HTH

  10. #25
    Join Date
    Apr 2007
    Location
    Columbus, Ohio, USA
    Posts
    3,441
    Quote Originally Posted by Jamie Schmitz View Post
    Did you say 1/8 inch laminate? I have never seen it that thick.
    I did not measure it, so I am only guessing. It seemed pretty thick to me, but it rolled up pretty well, which would indicate thinner. OK, now I am curious.... OK, it is less than 1/16" (pretty close though). Used a tape measure...

  11. #26
    Join Date
    Apr 2007
    Location
    Columbus, Ohio, USA
    Posts
    3,441
    Quote Originally Posted by Don Alexander View Post
    as to the OP's question, the best practice for what you are wanting to do would be to laminate top and bottom of the MDF and poly the exposed oak
    and seal the edge of the mdf where the cutout for the router is just don't soak that mdf edge or it will swell and mess up your top i often seal those edges with contact cement put on with a small roller for smoothness

    HTH
    In response to your "HTH", yes, it does.

  12. #27
    Join Date
    Feb 2003
    Location
    Dallas, Tx.
    Posts
    1,337
    Quote Originally Posted by Alan Lightstone View Post
    Can you laminate one side of MDF and seal the other side (and edges) with shellac and avoid problems, or is laminating both sides necessary.
    If you are securing the laminated MDF, such as a table top, you don't need to laminate or shellac the other side. If it were a stand alone, then yes I would treat both sides. Like a laminated counter top, there is no treatment to the back side.
    Phil in Big D
    The only difference between a taxidermist and the taxman, is that the taxidermist leaves the skin. Mark Twain

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •