Combining different types of wood for table-top: one better than the other?

Collapse
This topic is closed.
X
X
 
  • Time
  • Show
Clear All
new posts
  • radhak
    Veteran Member
    • Apr 2006
    • 3058
    • Miramar, FL
    • Right Tilt 3HP Unisaw

    Combining different types of wood for table-top: one better than the other?

    I am building a compact 'executive table' for myself (I work from home, mostly), and I have a nice 4x8 mahogany plywood that I could use for the table top, but want to use up all the hardwood I have, so...

    Looks like I have enough cherry to build a solid table-top, but not really long enough to span the 5' length. And I also want to have a bit of fun, so I thought of using another wood in the middle and to make breadboards at the ends.

    I have a board of 5" wide mahogany that's 5' long, and another 2" wide strip of white maple that's longer. I have enough smaller pieces of either to use for the breadboard and the vertical strip in the middle.

    The question is - does it matter, in terms of strength, etc, which wood I use with cherry? The other info here is that the cherry is 13/16" thick, while the mahogany is 1" and the maple is thicker, maybe 3/2 inches. I am hoping to avoid resawing or planing.

    The cherry boards lengths vary from 3 to 4 feet.

    Click image for larger version

Name:	TableTop.jpg
Views:	458
Size:	45.9 KB
ID:	830184
    It is the mark of an educated mind to be able to entertain a thought without accepting it.
    - Aristotle
  • leehljp
    Just me
    • Dec 2002
    • 8429
    • Tunica, MS
    • BT3000/3100

    #2
    Maple has more similar characteristics of Cherry than Mahogany does. The contrast for mahogany and cherry to me, is that the reddish color of both seem to fight for for attention unless the finish is wisely chosen and applied. I love the contrast of maple and cherry personally.

    A second characteristic is the movement. Cherry and maple move roughly the same, but mahogany has a different movement rate. Being that narrow of a strip will not affect it that much, but the small amounts do put stress on the glue joints in the long run, where there is a different rate of expansion contraction with weather changes.

    I am not an expert on this and I have a book somewhere that I cannot find - "Wood Movement" by Hoadley, that gives some great information on exactly what you are asking.
    Hank Lee

    Experience is what you get when you don't get what you wanted!

    Comment

    • capncarl
      Veteran Member
      • Jan 2007
      • 3564
      • Leesburg Georgia USA
      • SawStop CTS

      #3
      It kinda does matter if you mix wood up in a table. In the sketch you show 4 pieces of Cherry with a piece of mahogany running the length. What matters in this sketch is what you are going to do to keep it from breaking in half in the center. You can't just butt splice the end grain of the cherrry together and expect them to support any weight. The top should be able to support the weight put on the table and the aprons connect the legs and help support the weight put on the top.
      I've built a number of barnwood dining tables using small pieces of wood by staggering the lengths, creating a random design like you see in some wood floors. This is what I would suggest for this application. There is no reason that you couldn't also use the mahogany and Maple mixed up with the cherry. I've seen dining tables built with mixed woods that looked really good.
      The breadboard ends can't be fastened hard to the top, thus they offer no weigh support, the body of the table will expand/contract across the grain, the breadboard must allow for that movement.
      Last edited by capncarl; 04-30-2017, 01:57 PM.

      Comment

      • radhak
        Veteran Member
        • Apr 2006
        • 3058
        • Miramar, FL
        • Right Tilt 3HP Unisaw

        #4
        Thanks guys!
        Hank - I agree, the maple's bigger contrast might look better; I was wondering how I'd make the mahogany stand out against the cherry.

        Cap, you made me see the devil in the detail - I was not thinking of how I'd attach the cherry pieces to the strip laid across. I do see that I missed some detail in my earlier picture - those cherry pieces would actually be glued up panels themselves, like so:
        Click image for larger version  Name:	TableTop b.jpg Views:	1 Size:	53.1 KB ID:	830188

        If I read your advice right, I could instead just glue up by staggering the pieces? Like this, maybe -
        Click image for larger version  Name:	TableTop d.jpg Views:	1 Size:	45.7 KB ID:	830189

        I was worrying the end-grain when a piece butts against another wouldn't glue well, but maybe the longer edges would take care of that?

        Yes, I plan keep the bread-board ends floating, to allow wood movement. So I see your point - they don't add to the strength.
        Last edited by radhak; 04-30-2017, 09:08 PM.
        It is the mark of an educated mind to be able to entertain a thought without accepting it.
        - Aristotle

        Comment

        • leehljp
          Just me
          • Dec 2002
          • 8429
          • Tunica, MS
          • BT3000/3100

          #5
          You know that the famous people are those that went against the grain so to speak and did what others said not to! Referring to my maple over mahogany advice!
          Hank Lee

          Experience is what you get when you don't get what you wanted!

          Comment

          • mpc
            Senior Member
            • Feb 2005
            • 979
            • Cypress, CA, USA.
            • BT3000 orig 13amp model

            #6
            Radhak - in your upper pic of post #4 (showing the Cherry boards edge glued) what about:
            1: for the edge-glued Cherry boards, I'd make the width of each board consistent on either side of the "Mahogany or Maple laid across" vertical dividers so they look like boards that are nearly as long as the 60 inch table size. I'd also try to make the widths mirror images (symmetric) above/below the large horizontal Mahogany/Maple strip.
            2: use box joints or finger joints or some other end-to-end joining technique for the Cherry boards at the vertical "Mahogany or Maple laid across" divide.
            3: Then, to hide the ugly box/finger joints, make a shallow dado that you can then apply thin veneer pieces into to form the "Mahogany or Maple laid across" strip.

            Basically, make most of the tabletop glued-up Cherry pieces and use Maple veneer to add highlights and hide ugly end-to-end joints in the short Cherry boards. Being veneer, those Maple highlights won't cause oddball stresses in the rest of the panel from wood movement.

            Wanna really get crazy with the Maple? Where the long horizontal Maple piece meets the two vertical pieces, split the long horizontal into two pieces and cut "V" shapes on the ends of all 4 Maple pieces so you have 4 miters coming together. Possibly add a diamond-shaped medallion or some other decorative shape dead-center that the strips then radiate from.

            mpc

            Comment

            • capncarl
              Veteran Member
              • Jan 2007
              • 3564
              • Leesburg Georgia USA
              • SawStop CTS

              #7
              I'd take the center Maple piece, rip it in half and use it for the both outside edges to create an unbroken edge. The 2 breadboard edges are fine if you let them float. If you leave the Maple piece in the center it will be a distraction but when move to the edge it will highlight the cherry.

              Ive built a number of large table tops with with lots of small pieces with no biscuits, just glued up panels, and have not experienced a single problem. I will not discourage the use of biscuits or dominos though, they are a great building aid and make the glue up go a lot quicker.

              If you do do not have enough good wood to build the whole top, you can split all the wood on the band saw and double the surface area of good wood, then use a good sheet of plywood for the base and lay up the split wood on it.

              This calls for a story....... One of my work buddies lives in his grandmothers old house on the old family farm, the barns, blacksmith shop and other outbuildings have deteriorated beyond saving and are falling down into theirselves. I offered to build his wife a dining room table for a surprise Christmas present out of salvage barn wood for enough wood to build me a table . My buddy took my 16' trailer home and loaded a couple of forklift scoops of whatever wood they could gather up. Most of it was crap, even though it was old growth pine harvested in 1830's. Amoung the crap wood I happened to find grandmas old breakfast table, complete with 4 large turned legs. ( the table had been built on this farm out of poplar in the early 1900s). Out of the whole trailer load of old pine barn wood I was only able to salvage enough 3/4" thick wood to build one table top and aprons, no legs. This table top would not be thick enough to provided a good stable top. I milled each board from Grandmas poplar table top to 3/4" thick and built up a panel the size of the new table and glued the barn wood pieces on top of the poplar. Grandmas old table legs worked just fine. Now they have a new table that was built out of barn wood salavge from their old barns and was built on top of Grandmas old breakfast table! How cool is that? 6 years later, kept in an air conditioned house, all joints are good.
              Attached Files

              Comment

              • radhak
                Veteran Member
                • Apr 2006
                • 3058
                • Miramar, FL
                • Right Tilt 3HP Unisaw

                #8
                Great ideas, Cap, about putting the maple on the outside edges, and about using a sheet of plywood as an underlayment! I believe I might have enough to make the top, but adding a half-inch of plywood underneath is intriguing, particularly because my cherry is half the thickness of the maple and the ply might help me build up that thickness.

                And that story is so wild - I'd love to work on wood that old! That tabletop looks real good!
                It is the mark of an educated mind to be able to entertain a thought without accepting it.
                - Aristotle

                Comment

                • capncarl
                  Veteran Member
                  • Jan 2007
                  • 3564
                  • Leesburg Georgia USA
                  • SawStop CTS

                  #9
                  Since plywood is so prime to warp, especially the thin stuff, I'd suggest getting a plywood sheet with mdf, chipboard core or a marine honeycomb core. A $100 piece of plywood vrs. a $25 piece may well save your project from the scrap heap if it warps!

                  Calculate the thickness of your Maple edge banding boards to be the same thickness as the cherry + plywood base. If your Maple is not thick enough to do this, turn it on its side to get the desired thickness, or glue up a Maple board for the edges. A thick table doesn't sound like a drum when you use it like a thing top does.

                  Comment

                  • Black wallnut
                    cycling to health
                    • Jan 2003
                    • 4715
                    • Ellensburg, Wa, USA.
                    • BT3k 1999

                    #10
                    For end grain to end grain you could use a tongue and groove joint or fingerjoint if you have that cutter. Even a half lap. Just about anything would be stronger and proved for a better glue joint.
                    Donate to my Tour de Cure


                    marK in WA and Ryobi Fanatic Association State President ©

                    Head servant of the forum

                    ©

                    Comment

                    • capncarl
                      Veteran Member
                      • Jan 2007
                      • 3564
                      • Leesburg Georgia USA
                      • SawStop CTS

                      #11
                      I though that I would have already caught all kind of grief for suggesting gluing a pieced up table top to a sheet of plywood, and shouldn't have suggested it! It does go against all teachings because the wood top will expand at a different rate than the plywood and probably bow or cup. My table in the story and photo is laminated to grandmas old table which is 3/4" thick x 6-8" poplar boards which I side glued into 1 table sized panel, not plywood. I would suggest this method, not plywood. Big box store poplar boards would cost about as much as the cored plywood I previously suggested, I know for a fact they work.
                      When I started building tables I visited an older craftsmans shop that custom built tables. He shared a lot of his table top building secrets. Secret #1, use narrow boards if possible, 3" wide was his favorite. Wide boards look great but are prone to cup. Secret #2 use thick boards. 5/4 was his favorite. After all planing and sanding the final thickness is 4/4. Secret # 3, use short boards. Varying length boards, no one board over 1/3 the length of the table.

                      I chose to build SMALL tables, (Tiny Tables ) because large tables are too heavy and cumbersome to build, move around in the shop and deliver and hurt my back.

                      Comment

                      • radhak
                        Veteran Member
                        • Apr 2006
                        • 3058
                        • Miramar, FL
                        • Right Tilt 3HP Unisaw

                        #12
                        Originally posted by capncarl
                        ... the wood top will expand at a different rate than the plywood and probably bow or cup. My table in the story and photo is laminated to grandmas old table which is 3/4" thick x 6-8" poplar boards which I side glued into 1 table sized panel, not plywood. I would suggest this method, not plywood. Big box store poplar boards would cost about as much as the cored plywood I previously suggested, I know for a fact they work.
                        When I started building tables I visited an older craftsmans shop that custom built tables. He shared a lot of his table top building secrets. Secret #1, use narrow boards if possible, 3" wide was his favorite. Wide boards look great but are prone to cup. Secret #2 use thick boards. 5/4 was his favorite. After all planing and sanding the final thickness is 4/4. Secret # 3, use short boards. Varying length boards, no one board over 1/3 the length of the table....
                        I did wonder about the plywood causing problems with moving wood. Thanks for the heads-up; I'll look for another wood if I want to increase the thickness.

                        Mark's idea seems good - to use a half-lap instead of butt joins. Thanks Mark!

                        I did not realize using shorter boards might be a recommended strategy; is that because wood movement stays contained, maybe?

                        It is the mark of an educated mind to be able to entertain a thought without accepting it.
                        - Aristotle

                        Comment

                        • capncarl
                          Veteran Member
                          • Jan 2007
                          • 3564
                          • Leesburg Georgia USA
                          • SawStop CTS

                          #13
                          How thick is is your cherry? If it is 3/4" +- it is suitable for the 30x50 you want to build, without any underlayment. An executive table does not get the abuse a dining table gets.

                          As far as end jointing the boards, I know it is a nice thing to do, but just adds another layer of complications to the build, like getting everything exactly straight, same thickness etc. I've though about doing it but why. The boards are side glued continuously, and end glued, and are not going anywhere. The wood movement is side to side not end to end.

                          Id still recommend cutting the cherry widths in half. (Do you ever see a wide board cup and warp? Yep, nearly always. How about seeing a narrow board cup? seldom) My Tiny Tables use a 10-14" wide x 14-26" long top board. The wood is always highly figured and usually distressed and very prone to warping and cupping. If I can't make it flat with the plane and sander I will slice it into 2-3 boards, rejoint the edges and glue it back together. The glue joints are invisible and usually no one but me can tell it was ever cut apart. Of the 30 tables I built in 2016, probably 10 tops were cut this way.

                          Google How to Calculate Wood Shrinkage and Expansion, by Popular Woodworking Magazine. It's the best simple explanation of wood shrinkage and expansion and how to determine what you table will do.

                          Comment

                          • JimD
                            Veteran Member
                            • Feb 2003
                            • 4187
                            • Lexington, SC.

                            #14
                            I don't know what sort of table you envision for working from home. There is an interesting design at the Woodworking for Engineers website. It can be adjusted up and down so it can be used from a recliner (where I am now) and also adjusted up for other chairs. Potentially it could even be a stand up desk.

                            While the plywood could warp I don't think it will if it is tied into a structure. It isn't my experience that it does, anyway.

                            Comment

                            Working...