Loading ...
Sorry, an error occurred while loading the content.

RE: [MedievalSawdust] Grain in joints and finishing questions

Expand Messages
  • Glenn McDavid
    ... Roy Underhill discusses six-board chests in one of the _Woodwright_ books, including the differential expansion issue. Don t recall the details, but it
    Message 1 of 13 , Jul 1, 2006
    • 0 Attachment
      On Sat, 1 Jul 2006, Chuck Phillips wrote:

      > I suspect that the reasoning people are using for the original
      > recommendation is the differential expansion argument. A six-board is a
      > special case where other considerations override - Short grain failure
      > is much more likely than joint bond failure.

      Roy Underhill discusses six-board chests in one of the _Woodwright_
      books, including the differential expansion issue. Don't recall the
      details, but it can be made to work.

      Glenn McDavid
      gmcdavid@...
      http://www.winternet.com/~gmcdavid
    • Conal O'hAirt Jim Hart
      ... I didn t sleep much either last night.... forgive me if I was blunt. Baron Conal O hAirt / Jim Hart Aude Aliquid Dignum Dare Something Worthy
      Message 2 of 13 , Jul 1, 2006
      • 0 Attachment
        >
        > Charles Joiner
        > Rambling, running on 4 hours sleep.
        >

        I didn't sleep much either last night....
        forgive me if I was blunt.

        Baron Conal O'hAirt / Jim Hart

        Aude Aliquid Dignum
        ' Dare Something Worthy '

        __________________________________________________
        Do You Yahoo!?
        Tired of spam? Yahoo! Mail has the best spam protection around
        http://mail.yahoo.com
      • AlbionWood
        Most of the 16th c. six-board chests appear to have been treenailed; some appear to have used iron nails. Treenails have the advantage here as they are
        Message 3 of 13 , Jul 1, 2006
        • 0 Attachment
          Most of the 16th c. six-board chests appear to have been treenailed; some appear to have used iron nails.  Treenails have the advantage here as they are flexible, so can accommodate some cross-grain movement without splitting the boards.  Using kiln-dried quartersawn material also helps.  Thick stuff won't move as much as thinner.

          I use Tremont nails in slightly oversize holes.  My main problem is cupping as the boards shrink in dry climates; this is exacerbated by my use of 1/2" boards for the sides (to save weight).

          I made a couple of clamped-front chests with full 1" thick lids (milled from 5/4 lumber) treenailed to battens about 2" wide, as seen on surviving 13th to 15th c. chests.  I was worried about differential movement, but the customer reported the lid stayed flat.

          Speaking of clamped-front chests, this is another example of a medieval technique that modern authors would say cannot work.  The joints between the legs and the panels are cross-grain, and frequently involve wide boards.  Sometimes you can see where this has indeed caused the panels to crack, but quite a lot of them look just fine.  It's possible that the peg holes in the tenons were elongated (this is what I usually do), but it's also possible that the combination of flexible pegs and thick lumber accommodates all the cross-grain movement.

          Cheers,
          Colin


          msgilliandurham wrote:

          By "mechanically" do you mean with nails, dowels, or screws? or by
          cutting a strip out of the ends (esentially making one great big
          finger joint) I'm guessing both would be best.



        • msgilliandurham
          ... I m guessing from the context that treenailing is using some kind of narrow pegs as if they were metal nails -- but could you elaborate, please? ...
          Message 4 of 13 , Jul 1, 2006
          • 0 Attachment
            --- In medievalsawdust@yahoogroups.com, AlbionWood <albionwood@...>
            wrote:
            >
            > Most of the 16th c. six-board chests appear to have been
            > treenailed; some appear to have used iron nails.

            I'm guessing from the context that "treenailing" is using some kind
            of narrow pegs as if they were metal nails -- but could you
            elaborate, please?

            > I use Tremont nails in slightly oversize holes. My main problem is
            > cupping as the boards shrink in dry climates; this is exacerbated
            > by my use of 1/2" boards for the sides (to save weight).
            >
            > It's possible that
            > the peg holes in the tenons were elongated (this is what I usually
            > do), but it's also possible that the combination of flexible pegs
            > and thick lumber accommodates all the cross-grain movement.

            Elongated how, please?

            Also, the book which started my thinking about this issue, says
            that "when assembing a box or drawer [this is one where the grain of
            all four sides is the same] turn the boards so tha annuual rings
            curve out [...] The board's natural tendency to cup will keep the
            corner joints tight at the edges."

            Gillian [grateful with the patience of this group for her questions!]
            Durham
          • albionwood
            ... Treenails are basically wooden nails. There really isn t much difference between pegs and treenails, except the latter sounds cooler. It s more the way
            Message 5 of 13 , Jul 1, 2006
            • 0 Attachment
              --- In medievalsawdust@yahoogroups.com, "msgilliandurham"
              <msgilliandurham@...> wrote:
              >
              > > I'm guessing from the context that "treenailing" is using some kind
              > of narrow pegs as if they were metal nails -- but could you
              > elaborate, please?

              Treenails are basically wooden nails. There really isn't much
              difference between pegs and treenails, except the latter sounds
              cooler. It's more the way they are used that's different: Treenailing
              implies (to me at least) fixing one board atop another, whereas
              pegging is a way to lock mortise and tenon joints together.

              Note well, however, that these terms aren't rigidly defined, so other
              writers may use them in different ways. (I think in boatbuilding a
              treenail means a peg with a head, like an unthreaded bolt, so it can't
              be pulled through a board. But what I know about boatbuilding
              wouldn't cloud your vision if it was in your eye, so...)

              >
              > Elongated how, please?

              When pegging a wide, cross-grain mortise-and-tenon joint, you can
              elongate the peg holes in the tenon so that the tenoned board can move
              without opening up the joint. For example, a breadboard end might be
              fixed with three (or five) pegs. The center one is done the usual way
              (i.e. drawbored - the hole in the tenon is offset slightly toward the
              shoulder, relative to the holes in the mortise) so all movement is
              away from the center. The other holes (also drawbored) can be
              elongated slightly across the grain, so that the tabletop can shrink
              or swell without cracking.

              I don't think this was ordinarily done much in the MA because thick
              riven planks don't actually move that much, and because the pegs are
              flexible enough to accommodate some movement. But I wouldn't be
              surprised to see it on clamped-front chests or tabletops in the late MA.


              > Also, the book which started my thinking about this issue, says
              > that "when assembing a box or drawer [this is one where the grain of
              > all four sides is the same] turn the boards so tha annuual rings
              > curve out [...] The board's natural tendency to cup will keep the
              > corner joints tight at the edges."

              This is true only if the board is losing moisture and shrinking. The
              outside of a log shrinks more than the inside, so it cups opposite the
              curvature of the rings. It's also only true for plainsawn (flatsawn)
              lumber. Quartersawn lumber has little tendency to cup.

              Cheers,
              Colin
            • Chuck Phillips
              Conal; Even if intended (and I m sure none was), no offense was taken. This is one of the most civil mailing lists I ve even subscribed to. Charles Joiner A
              Message 6 of 13 , Jul 2, 2006
              • 0 Attachment
                Conal;

                Even if intended (and I'm sure none was), no offense was taken. This is
                one of the most civil mailing lists I've even subscribed to.

                Charles Joiner
                A little better rested now, watching Le Tour on the TV.

                -----Original Message-----
                From: medievalsawdust@yahoogroups.com
                [mailto:medievalsawdust@yahoogroups.com] On Behalf Of Conal O'hAirt Jim
                Hart
                Sent: Saturday, July 01, 2006 12:41 PM
                To: medievalsawdust@yahoogroups.com
                Subject: RE: [MedievalSawdust] Grain in joints and finishing questions


                >
                > Charles Joiner
                > Rambling, running on 4 hours sleep.
                >

                I didn't sleep much either last night....
                forgive me if I was blunt.

                Baron Conal O'hAirt / Jim Hart

                Aude Aliquid Dignum
                ' Dare Something Worthy '

                __________________________________________________
                Do You Yahoo!?
                Tired of spam? Yahoo! Mail has the best spam protection around
                http://mail.yahoo.com



                Yahoo! Groups Links
              • Geffrei Maudeleyne
                A short story on grain. In High School we designed and built our own furniture instead of bird houses. I designed a game table with a checkerboard in the
                Message 7 of 13 , Jul 2, 2006
                • 0 Attachment

                  A short story on grain.

                   

                  In High School we designed and built our own furniture instead of bird houses. I designed a game table with a checkerboard in the middle. The board had all of it’s grain going in one direction. Then I wrapped it in a frame of walnut with the grain going along the sides of the checkerboard. I filled out the bulk the table top with poplar that ran in two directions and then banded the eight sided table top with walnut that ran in four different directions. The walnut came from someone’s grandfather’s barn attic, many years old. The poplar was kiln dried.

                   

                  My shop teacher was in on all of this planning and execution. He should have been executed. We built our projects an hour a day for several months so it did not get a finish until late in the game. By then it was too late anyway. Wood, even when removed from the tree grows and shrinks. I had to fight the top to re-glue all the joints when they pushed each other apart. In disgust, the table now has a painted piece of birch plywood.

                   

                  Projects like the 6 board box have room for the legs to get longer etc. you have just an angle to another.

                   

                  Compare to:

                  -l-l-l

                  l-l-l-

                  -l-l-l

                  If the lines crudely denote grain direction. The interior swelling and shrinking directly affects every other joint. Adding things like dovetails, biscuits, dowels and pegs also affect your results.

                   

                  Geffrei


                  From: medievalsawdust@yahoogroups.com [mailto:medievalsawdust@yahoogroups.com] On Behalf Of msgilliandurham
                  Sent: Friday, June 30, 2006 9:07 PM
                  To: medievalsawdust@yahoogroups.com
                  Subject: [MedievalSawdust] Grain in joints and finishing questions

                   


                  My thanks in advance for any responses I get to the questions below.
                  (and yes, this group will get *heavy* mention in my class next
                  weekend! :-)

                  Question one:
                  I've been reading some books on modern carpentry (filling in the big
                  honking gaps in my very rough-and-ready knowledge) and one of them
                  insists that for a box with a lid, the front, back, and sides of the
                  box all need to have the grain running the same way, (i.e., parallel to
                  the bottom) or "the joints will fail".

                  trimmed for digest users.

                Your message has been successfully submitted and would be delivered to recipients shortly.