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RE: [MedievalSawdust] Grain in joints and finishing questions

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  • 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
      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
    • msgilliandurham
      ... 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
      Message 2 of 13 , Jul 1, 2006
        --- In medievalsawdust@yahoogroups.com, "Chuck Phillips" <chuck@...>
        wrote:

        > Structurally, cross-grain joints are inherently weaker and
        > less durable.
        > [...] Most adhesives will
        > eventually fail in this situation, and unless you take measures to
        > mechanically lock the joint, it is destined to come apart.

        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.

        > With that said, I think it is more important for your design
        > to avoid small sections of short grain in the foot sections.
        > Regardless of how good a box looks, if a leg snaps off the
        > whole thing becomes firewood.

        Oh, DU'UHHH! <sigh -- *think* Gillian, THINK!>

        >
        > #2: Wax alone is a pretty poor moisture barrier. Boiled Linseed
        > Oil (or BLO) is a better barrier that will actually build a bit of
        > a film. I'm not sure why people would find it intimidating.
        > All you need to do
        > is wipe on a coat, let it soak in for a few minutes, and wipe
        > off the
        > excess. After it cures for a bit, additional coats can be wiped on
        > until the desired thickness is achieved. Once you're happy with the
        > surface film, wax will provide a smoother feel and help prevent dust
        > from sticking.

        I guess the oil seems more toxic to me than just wax -- not as
        practical to use if you are doing this in your apartment :-) -- more
        flammable, smellier, etc.

        I'd be willing to put on a wax finish in the bathroom with the
        exhaust fan running -- BLO I'd really want to do outside, which would
        mke my nosy neighbors whine to the complex management, wno would come
        down on me ...

        There's also that judgment factor of how long to let it cure, and
        the "desired thickness". All I'm saying is that there's more of a
        learning curve involved.

        And thanks for the book reference -- probably won't be able to get my
        hands on it before the class, but I'll definitely look it up.

        Thank you so much for the help -- Gillian Durham
      • msgilliandurham
        My thanks to you both -- and Milord Charles -- go get some sleep!! I m thinking the wicking up the feet issue could be solved easily enough by 1) Dipping the
        Message 3 of 13 , Jul 1, 2006
          My thanks to you both -- and Milord Charles -- go get some sleep!!

          I'm thinking the "wicking up the feet" issue could be solved easily
          enough by

          1) Dipping the feet in warm wax until they will absorb no more wax,
          and have a thin coating on the outside

          2) setting the feet on pieces of glazed tile,

          3) capping them with boiled leather or [horrors] pleather.

          None of which are documentable, but then how many of our medieval
          ancestors left their furniture sitting outside for a week or two at a
          time, several times a year??

          [g,d, & r]

          Thanks again -- Gillian Durham

          --- In medievalsawdust@yahoogroups.com, "Chuck Phillips" <chuck@...>
          wrote:
          >
          > Conal;
          >
          > You're absolutely correct. Teach me to go spouting off in the wee
          hours
          > of the night. This would explain why every example of a six-board
          I can
          > recall has the grain oriented vertically on the ends.
          >
          > 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. We are still left
          with the
          > issue of placing end grain directly on the ground, which will
          eventually
          > lead to rot if there is any moisture. Adding some feet will help
          here,
          > at the cost of making the chest something other than a true six-
          board...
          >
          > Charles Joiner
          > Rambling, running on 4 hours sleep.
          >
          > -----Original Message-----
          > From: medievalsawdust@yahoogroups.com
          > [mailto:medievalsawdust@yahoogroups.com] On Behalf Of Conal O'hAirt
          Jim
          > Hart
          > Sent: Saturday, July 01, 2006 5:56 AM
          > To: medievalsawdust@yahoogroups.com
          > Subject: RE: [MedievalSawdust] Grain in joints and finishing
          questions
          >
          >
          >
          > --- Chuck Phillips <chuck@...> wrote:
          >
          > > I'll pick up this gauntlet. (Why am I still awake?
          > > I have to be at a
          > > client in 9 hours!)
          > >
          > > Regarding question #1: Grain orientation matters
          > > for a number of
          > > reasons. Visually, it is more pleasant to have
          > > continuous lines
          > > wrapping around the sides. This is more noticeable
          > > in a slab-sided
          > > piece like a six-board chest, less so in frame and
          > > panel construction.
          >
          > in a six board chest the sides and the ends
          > SHOULD have the grain running in different
          > directions.... 'cause of the 'feet' on the ends
          > ( a drawing would better illustrate )
          >
          > Running the grain the same as the sides would make
          > the feet weaker and easier to break off.
          >
          >
          >
          > Baron Conal O'hAirt / Jim Hart
          >
          > Aude Aliquid Dignum
          > ' Dare Something Worthy '
          >
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        • 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 4 of 13 , Jul 1, 2006
            >
            > 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 '

            __________________________________________________
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          • 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 5 of 13 , Jul 1, 2006
              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 6 of 13 , Jul 1, 2006
                --- 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 7 of 13 , Jul 1, 2006
                  --- 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 8 of 13 , Jul 2, 2006
                    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 '

                    __________________________________________________
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                    Tired of spam? Yahoo! Mail has the best spam protection around
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                  • 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 9 of 13 , Jul 2, 2006

                      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.

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