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    Basic Woodworking

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    Join date : 2011-05-30

    Basic Woodworking

    Post  Admin on Wed Jun 01, 2011 10:57 pm

    By Master Tamlene ap
    Guidgen



    Craftsmanship can be defined in
    a lot of ways. A fairly common usage includes the
    statement do your
    best work in all tasks”. Something that is often
    misunderstood in this statement is the difference between
    doing your best and perfectionism.
    Doing your best means that you must reach
    a compromise between your absolute best work (which takes a very long
    time), and work which is of good quality but still allows you to get something
    done. Almost everyone errs on the side of trying too hard to do
    perfect work, and thus getting very little done. Perfectionism includes
    the work which commonly graces the covers of magazines like Fine Woodworking.
    Work like this is something to aspire to, and be inspired
    by. It takes a huge amount of experience to do work of
    Fine Woodworking caliber.



    It is very important to include
    the amount of work you get done in any estimate of how close you are to
    “working at your best”. If you only do one piece each year,
    your abilities will not improve very
    much. Twenty shoddy pieces each year
    will also not improve your
    abilities much. Neither case is “working at
    your best”. You must strike a balance, and
    realize that medium quality work actually represents your best
    work in the long run.



    Do not be a slave to your
    ruler. Measuring things as a specific
    number of inches is a fairly modern concept, and
    can take over a project unnecessarily. What usually
    matters more than inches is
    proportion. Sometimes there is
    important dimensionality, but what counts is that
    something fits, not that it is so many inches. I often
    measure in hand spans. If you want
    accuracy, you can mark the dimension carefully
    on a piece of scrap. For proportion, a pair of
    dividers works well to pace off the work. Rulers are
    useful things, but please keep an open mind and avoid being
    compulsive about them.



    Power tools are very oversold. Also
    oversold is sand paper. Both are extremely useful in
    their place, but in a home workshop their place is limited.



    Hand tools are generally faster,
    have fewer health hazards and are much more pleasant to work with than power
    tools. In order to know the truth of what I am saying, you must be willing
    to work with a hand tool long enough to gain some proficiency
    with it. Only after some mistakes and slow work will you begin to
    see the efficiencies inherent in a given hand tool.



    Power tools can speed up
    repetitive work. Very little of what is done at home is
    repetitive enough to justify the time spent setting up
    a power tool and cleaning up the amazing
    mess afterward. Also not
    justified is the noise and dust, and
    the sheer amount of space occupied
    by power tools. I own many, and speak from experience. I only use a few.



    There is another aspect of hand
    tools which is really nice. Hand
    tools give you the option of spending
    money to acquire them, or spending
    time to make them. Most any hand tool can be made for almost
    no monetary expense. If you don’t believe
    me, come to Unser Hafen Blacksmithing Guild
    some time. We’ll make you some tools.



    Some tasks are repetitive enough
    that power tools make sense. Rip sawing (reducing the width of a long
    board) is really a lot of work and not terribly entertaining. Rip
    sawing is very sensibly done with power tools in these days of no
    apprentices. Surface planing of rough lumber is also sensibly done with power
    equipment.



    Surface smoothing for finishing
    is not a good use for sand paper. Most
    surfaces are much better attacked with
    a hand plane and a
    scraper. To make a coarsely smoothed surface very smooth takes
    a lot of time with sand paper (power or hand sanding). A plane and a
    scraper do the job quite quickly. As a surface gets more curved, or
    smaller, planes and scrapers make less sense and sandpaper makes more.


    Introductory
    Woodworking





    If you sweep the floor clean
    before you start, and throughout your work, it is much easier to find pieces of
    wood which accidentally chip out that were not supposed
    to be removed. The piece can easily be
    glued back with either yellow wood glue or cyanoacrylate glue, with
    none the wiser.


    1.
    Marking accurately and squarely





    Making wooden joints often
    involves careful marking of your piece of wood. If your marks are
    not in the right place, you have no hope of sawing or chiseling accurately. You
    rarely need to mark a specific distance on a board—rather,
    you may need to mark an identical distance
    (however long) on two boards. The tool used
    for this task is a marking gauge. It consists of
    a sharp point attached to a stick. The stick
    is in turn held by a block of wood
    (fence). The mark is made by putting the fence against
    the edge of the board to be marked and scoring
    the surface of the board with the
    sharp point. The distance between the
    fence and the sharp point is adjusted by a clamp which
    holds the stick to the fence.



    Another type of mark you need to
    make is a mark perpendicular to one edge of a piece of
    wood. To do this, you need an accurate square (you also
    need a nice straight edge on the wood, discussed
    later). You can buy a good square, or make a cheap one accurate by
    adjusting it. A good test for a square (and also for your
    marking ability) is to draw a line
    around the entire circumference of a board
    perhaps three or four inches square. Does
    your line meet the starting place exactly?



    How you make a mark can also affect
    accuracy. A pencil line, even a fine one, has a lot more
    error in its width than most wooden joints will tolerate. There are
    two ways around this error. One is to use a knife edge to scribe a
    very fine line, and then work carefully to this line. The other way
    is to use a pencil line, and then fit two pieces to each
    other (and promptly mark them unambiguously
    as belonging to each other). Either way works
    well, although if you use a pencil, it should be a fine one.


    2.
    Cutting to a line





    First, start with sharp tools.
    You cannot cut accurately (hand or power) with dull blades. See the appendix.



    Whether you are cutting with hand or power
    tools, watch the wood and the mark, not the
    blade. Making an accurate cut requires practice and attention. A saw cut needs
    to start straight. You cannot force the saw direction without ruining your
    accuracy. Cutting straight is easy when you start straight.



    You can avoid cutting
    past your stop line if you realize that it is not
    necessary to cut all the way to it. You only need
    to cut to within one saw kerf of the stop
    line. When all sawing is done, clean up the tiny bit
    remaining in the corner with a chisel.



    Starting a cut with a
    hand saw is sometimes a bit tricky. At
    first, the saw will sometimes jump and shudder
    everywhere except at
    your mark. This is typically caused by either using too
    coarse of a
    saw for the hardness of the
    wood, using the wrong type of saw
    (crosscut vs. rip) or putting pressure on the saw. Even after a cut is
    started, you will get the most accurate cut if you
    let gravity feed the saw. If you should end up
    having started the cut slightly in the wrong place, instead of
    trying to force the saw to your will, lay the
    saw down almost flush with the
    surface and gently broaden your starting cut
    until you can saw in the correct place.


    3.
    Planing a straight edge





    You can plane a much
    better straight edge by hand than with a
    power jointer or router. To do this, you need
    the longest (sharp!) hand plane you can find. I use a No. 8 jointer
    plane, which is about 24 inches long. You must have some
    arrangement for holding the board to be planed without requiring any
    attention from you. Your cuts will not be true
    if you have to hold the board with your elbow and knee
    while you plane. At the start of a cut, push down on the front of
    the plane only. At the end of the cut, push down on the back of the
    plane only (at the handle). Think
    of your action as trying to plane a concave
    edge, and you will end up with a straight
    edge. Eyeball the edge when you are done—it should be
    absolutely straight after only a little practice.



    If it is important to
    have the edge exactly at 90 degrees to the face, lay the
    board on it’s face, spaced about 1/8” above the
    bench. Now lay the plane on it’s side, and plane the edge. If you do
    a lot of this, you should build a fixture for
    it so that you don’t wear a groove in your
    workbench.


    4.
    Gluing up boards





    Spend a lot of time before you
    apply glue arranging your boards so that matching edges end
    up next to each other. Mark adjacent edges
    (and front/back) so you can find the arrangement again. If you
    choose and arrange your boards carefully, most people will not
    realize that your nice wide board is glued up from smaller ones.



    To glue two edges together with no gaps, the
    edges both need to be absolutely straight, and at complimentary
    angles to each other. The edges do not need to be at 90
    degrees to their faces. To joint two boards to
    match, lay the boards next to each other on the bench in the
    preferred final orientation. Now pick them up, and fold
    them as if there is a hinge joining them. Clamp them in your vise
    this way; back to back or front to front. Now joint the edge. If
    your planing results in a nice straight edge which is a
    bit off of 90 degrees, you will still have a
    flat panel when gluing is done since the errors in the
    two boards will cancel each other.



    If you are forced to close gaps between
    boards with a lot of clamp pressure, something is wrong. If you have done your
    edging right, you should be able to apply glue to the
    edges, push and wring the edges together and get them to
    stick to each other with no clamps, just the surface tension of the
    glue. Try it some time, it is a lot of fun.



    Don’t use an
    excessive amount of glue. Some
    books and articles will admonish you to “get
    the right amount of squeeze out” when you
    clamp. The right amount of squeeze out is none. You do
    need to make sure glue coats the entire edge (both pieces!), so in
    practice you get some squeeze out. The ideal would be to have glue
    just come up to the edge and no farther. When you apply
    glue, make sure it covers each edge completely, in as
    even and thin a layer as you can.



    I usually space my clamps between one and
    two feet apart for edge gluing ¾” thick stock. It is nice
    to have more clamps than you think you need in case a problem comes up when you
    are clamping. Alternate the clamps top and
    bottom to keep the surface flat. With one inch and
    thicker stock, you can get away with a lot in terms of
    clamp spacing and uneven pressure between
    clamps if your edges mate nicely. When edge gluing
    ½” and smaller, you must be very careful to
    get even clamping pressure. Tighten the clamps little by
    little, so that they all reach final pressure together. As you
    tighten, check the face for flatness, to make sure you are not
    introducing a cup into the panel.



    Take great care in making the
    faces of your boards all lie in the same plane. This
    can save you a tremendous amount of work later. If you tighten your
    clamps little by little, it is much easier to adjust the edges. If
    you adjust the edges with the clamps too tight, you will introduce a bend in
    the board. If you have a hard time with this, or have a
    panel which must end up with a really flush surface, invest in a
    doweling jig, and put dowels in to align the edges.


    5.
    Planing end grain





    A block plane is specially
    designed to be able to plane end grain. If your plane is very
    sharp, and you take a nice thin cut, end grain
    is fairly easy to plane. Be careful at the far
    end of the board, however, as it is
    easy to tear a huge chunk off of the edge. You can either plane both
    ends against the middle, or else clamp the board to be planed firmly
    up next to a piece of scrap to support the
    far edge. Sanded end grain looks nothing like planed end
    grain.


    6.
    Avoiding cross grain construction





    When two pieces of
    wood are attached rigidly to each other, and the grain
    on one piece is perpendicular to the grain on the other, a
    split will inevitably develop with time. Wood
    expands a lot more perpendicular to the grain
    than parallel to the grain.



    A lot of period chests are made with cross
    grain construction, and have the splits to prove it. A lot of known world
    workmanship also has cross grain construction, and will either split or come
    apart at the cross grain joints in
    time. A common chest design in the current
    middle ages has grain running horizontally front and back, with
    grain running vertically on the end pieces (which extend below the bottom of
    the chest as legs).



    There are
    three reasons for building
    chests with cross grain
    construction—ignorance, “its period”, and
    expediency. I feel that only the first reason is valid.
    The second reason is not valid—there are many period examples of
    chests with no cross grain construction, including
    properly constructed cases and also frame and panel. The
    third reason is quite questionable in
    my mind. If you are not
    interested in your work lasting, then you must have
    quite different motives from my own.


    7.
    Sharpening





    If you want to risk your tools,
    you can try using a high speed motorized grinder. Several
    things can improve the risk:



    ·
    slow the grinder down to 1725 rpm


    ·
    get “cool” type grinding wheels


    ·
    back the blade you are
    sharpening with a larger piece of
    metal (a heat sink). Before grinding, dip the
    assembly in water. The water wicks up between
    the two pieces of metal ensuring good thermal contact.



    A much better choice is a hand
    powered grinder—not because of any hand tool mystique, but because
    it is extremely difficult to overheat your tools with a hand grinder.



    Either of the above methods should give you
    a hollow ground edge.



    Use either a small square or a sharpening
    jig to check your edge accuracy



    Before you can sharpen the edge
    you rough shaped, you must polish the back of the blade. You need to
    gradually move to finer and finer abrasives in the polishing process. I follow
    any rough grinding with a fine Carborundum stone (“India”
    stone), followed by a Washita stone. If the tool
    is a particularly nice one I end up on a “Soft Arkansas” stone. There
    are at least two finer grades than “Soft
    Arkansas”, but I have
    not found them to noticeably improve matters
    in general woodworking.



    The back should be very flat and shiny when
    you are done. Only when the back is polished does it make sense to
    fine sharpen the edge of the blade. You only need to get
    the tip of the hollow ground edge sharp. Now you can proceed to sharpen the
    hollow ground side.



    When you sharpen a blade, hold
    it very near the edge, and move the blade in small circles. You will have much
    better control of the blade angle.


    8.
    Sanding





    A lot of the
    time, sanding makes some sense. Surfaces which have
    grain pointing different directions (such as curves) can
    be insanely difficult to work with edged tools. Flat surfaces are very efficient to smooth
    with a plane after you have some practice in its use. If
    you have never used a plane, get a small block
    plane, read about how to use it and use it for a bit on
    every project you make. Using a plane without any experience
    and not using sandpaper at all will slow you down a
    lot. Get some woodworking done while you gain planing experience
    gradually.



    Sanding
    is most effective if you
    start with a coarse enough
    abrasive. Your abrasive must be almost as coarse as the irregularities in the
    surface. Typically, start with 80 grit paper (60 grit
    if you are trying to remove a bunch of
    wood). 80 grit paper is good for
    removing typical power tool marks, like a machine planed
    surface. If you want your surface to stay flat, wrap the sand paper
    around a flat block rather than holding the paper in your hand. Sand
    all areas which need it with #80 before changing grit size.



    The largest jump in grit size
    you should make is about 1.5 times as fine. If you
    started with #80, your next choice should be no finer than
    #120, followed with no finer than #180, etc. If you take
    larger steps, it will make your sanding take a lot longer. At each
    grade you use, be sure to sand all of the areas you
    sanded with the previous grit. Work in high
    contrast lighting, like direct sunlight, so that
    you can see the scratches in your work from the
    previous grit. Take them all out before going to a finer
    grade. If scratches show up after
    you start on a new grit and don’t
    sand out quickly, you should consider going
    back to a bit coarser grit for a while.



    For
    everyday projects, you can stop at #150 or
    #220. There is little point in
    using any finer grits on items
    you plan on taking camping with you. For
    surfaces you want smoother that are made of harder woods,
    it can make sense to go all the way up to #600.


    9.
    Finishing





    I don’t know a lot
    about finishing, so I use a couple of easy
    methods, oil finish and varnish.



    Oil finish brings out a lot of
    inherent color in the wood, and is available in ‘natural’ and
    various stains. A couple of good brands are Watco and Deft. Read the
    directions! I do not recommend linseed oil or dried linseed oil, as they take a
    lot longer to dry.



    Oil finishes can be enhanced by
    applying a wax after they are quite dry. You need a
    wax intended for the purpose that is compatible
    with an oil finish. Watco makes a wax specially made
    to work with their oil. I haven’t done much of this, but
    it can be very pretty.



    Varnish
    provides much more protection
    to the wood than oil.



    Varnish soaks into the wood and
    hardens, making the wood surface much more tolerant
    of abuse. Most varnishes also provide much more
    protection against water than an oil finish. If your wood will spend a lot of
    time in sunlight, get a polyurethane varnish for outdoor use.



    The
    difficulty in using varnish
    lies in not getting little
    hardened drips of varnish at the bottom edge of
    your piece. Varnish also takes the patience to
    apply several coats. I use Last and Last
    brand primarily because we have some left over from when
    we did our wood floors. Read the directions!
    It is
    very important to read the directions on
    finishes. Especially Important is the fire danger which finish saturated rags
    or paper towels represent. As the finish dries, a small amount of heat is
    generated. If the heat is confined, like in a wadded up
    towel in the trash can, the material can
    spontaneously combust hours later. I throw my
    finish rags in the wood stove. I prefer
    a satin finish to a gloss finish. Try both, and see what you like.



    Cutting
    dovetails



    Dovetail joints are really fine
    things. They are both esthetically pleasing and amazingly strong at
    the same time. Mortise and tenon joints are
    strong, not much easier than dovetails, and when
    you are done, no one can see all of your work! Dovetail joints have a bit of terminology
    associated with them. One side of the joint is
    called the tail, because the fan shape is
    reminiscent of a spread dove’s tail. The other side of
    the joint is called the pin (why I
    have no idea). Be careful as some authors
    reverse this.


    1.
    Stock preparation




    Leave your stock long while you prepare
    one edge. Taking all of
    the pieces out of one board is a smart
    idea, as they will match better. Make
    one edge of your board absolutely straight with a long
    plane. This edge will end up as the reference
    edge from which all measurements and
    alignments are made. Leave the other edge rough so that the
    difference is obvious.





    Using an accurate square, draw lines perpendicular to your
    reference edge to mark out the lengths of wood
    you will be using. Remember that your
    saw cut has width, and keep the saw in the same place in
    relation to your line. Either cut on one side of the line, or down the middle
    of the line, but do the same thing the entire length of the board.



    Do not cut your stock to final size. Allow
    yourself some room. The pins and tails of your joints (on each end of the
    board) should be perhaps 1/32” extra long, so that when
    the joint is assembled a bit extra sticks
    out. This allows you to end up with
    a flush surface (by planing away the excess), rather than a sunken
    one. You should also expect to do some finish planing on the other
    edges, those not involved in a joint.



    The edges
    of your boards should be
    cut square and even. Any wavering
    in the edge, especially in the end grain, must be allowed for
    when you mark your stock so that you don’t end
    up with a recessed
    tail. If the end grain is not square
    to the edge you may have such misalignment
    that it will be impossible to assemble all
    four corners at once.



    Check
    your pieces after you cut them with a square
    and straightedge. If the end grain is not square to the reference edge, or if
    your cut wavers, it is usually a lot easier to plane the end smooth and square
    now. You should also compare sizes on pieces which need to match
    each other. I often plane two pieces at once in the vise so that they are
    exactly the same size. If they are not the same size, your box will be
    trapezoidal instead of rectangular.



    Mark the orientation of your
    boards if it is important (mainly for appearance). You will have a
    hard time figuring it out later.


    2.
    Marking





    Set your marking
    gauge just a bit more than the thickness of the
    boards you are using (1/32” or so). Lightly
    score the boards to be
    dovetailed together, along the edges to be
    joined. I usually score
    face, back, and edges for each board
    in each joint. These marks indicate the
    edges of the pins and tails. The marks also show where the inside edge of the
    board forming the other half of the joint lies. If your marks do not
    end up straight lines, your finished assembly will show gaps along this edge.


    3.
    Cutting tails





    You must have very good lighting
    to cut dovetails. You must have light down on your bench
    for marking and measuring. You must also have light from the side (or below) so
    that you can see while sawing. Get a lamp which you can place where you need it
    and you will save lots of frustration and squinting.



    There are a lot of
    sequences which work in cutting dovetails. I like to cut
    the tails first, but it also works to cut the pins first. Begin by deciding how many dovetails you are
    going to put in an edge, where they will go, and how big
    they should be. Some of the considerations follow:



    If you space your dovetails
    unevenly (as I almost always do), put them near the high stress
    points. In a box, the stress is mostly along the top and bottom, especially the
    top edge.



    Evenly spaced
    dovetails, especially with pins and tails the same size,
    is what you get out of a dovetail template. Why try to imitate a
    router? This is kind of a modern argument, one that
    didn’t occur to people in the middle ages.



    At the edges of your joint, there will
    typically be either half of a tail or pin. Half of a pin is stronger than half
    of a tail, and a better choice.



    I usually mark the centers of
    the tails first, once I have decided on a layout. In marking the
    tails, please note that accuracy is not critical. The
    pins will be sized to fit the tails by marking them from the finished tails.
    Whatever angles, size and spacing your tails end up with, your pins will be cut
    to match.



    If your tails have identical
    spacing on two or more corners, it is a lot easier to mark the locations on a
    piece of scrap and transfer the marks from the scrap to both corners. This
    greatly reduces mistakes and speeds up the work.



    Use a pencil to mark the
    tails. With ring-porous woods like oak,
    it is easy for a knife mark to get lost in the
    grain. Also it is
    difficult to draw a straight line not quite in line
    with the grain using a knife blade. The grain pulls the
    knife off of the line you are trying to draw.



    Draw the tails using
    a bevel gauge. I set mine to an angle of about
    1:6 (1 over and 6 up). People seem to use a variety of
    angles, including 1:8 and 80 degrees. Draw the tails between the
    scribed line and the end of the board. Now go along the edge and X
    out all of the pieces which are to be removed (in pencil). Look
    carefully at what you have
    drawn. Did you really cross out the scrap, not
    the good parts? Are you tails drawn right, or are they reversed? Look
    carefully, this is easy to mess up!



    Using a small square, extend
    the lines you have drawn straight down the end grain
    across the thickness of the board, marking each side of the tail.



    Put the piece of wood in a
    vise, edge up. Start sawing along the mark in
    the end grain until you have a shallow groove. Now rotate
    the saw so it is pointing straight up and down and make a shallow groove along
    the face of the board. Now angle the saw more and more, joining the
    two saw marks you have made along the diagonal.
    Be careful not to cut beyond the scribed line
    on the face of the board. By working
    back and forth along these grooves, you can guarantee
    that the cut
    will be in the right place when it comes out
    the far side of the
    board. This is a good thing to practice a lot
    on scraps of wood, either making square or
    angled cutoffs. Remember not to force the saw.



    Saw
    carefully along the pencil
    lines, on whichever side you
    choose, not quite up to the scribe line. Once the cut is
    deep enough that the saw is self guiding, bring the saw
    horizontal and saw down
    almost to the scribe line. Check both sides of
    the board as you approach the
    scribe line so that you don’t unknowingly saw past the
    line on one side of the board.



    Since you are going to use the tails to mark
    the lines for cutting the pins, the
    size of each tail is not critical. This is, however, an
    excellent chance to practice your sawing to a line. Now you
    need to remove the waste from between your saw cuts.



    Before you start, once again
    examine your X’s marking the waste pieces to be removed. Are you sure they are
    in the right place? You can use either a fine turning saw or a chisel for
    rough stock removal. I use a mortising chisel.



    The type
    of chisel you use
    for rough stock removal is not
    critical, as long as it is narrow enough so
    it doesn’t score the inside edges
    of the tails. Your chisel must also be tough enough to
    deal with rough stock removal. Many bevel edge chisels
    will chip if you use them for chopping.



    Each time you start work in a
    new spot, ask yourself if that spot is really waste
    material. Every time you pick up the
    board you are chiseling on, you must clean the
    area underneath it. A small chunk of wood can make a nasty dent in the surface.



    First remove most, but not all of the waste.
    Leave a bit of waste, maybe 1/16” in front of the scribe
    line. Chisel down onto a piece of scrap on your workbench so that
    you don’t cut into your bench. Chop down, and then chip out the part you have
    cut through (from the end grain). Proceed like this at least halfway
    through the wood, and then turn
    the board over and finish the cut from the
    other side.



    Now move your chisel
    to the scribed line. For this cut you might want to
    sharpen your mortise chisel or use a bevel chisel. Tap the chisel
    gently with a mallet to set it in
    the line, and then tap a bit harder
    until you are about halfway
    through. Do the same thing from the other
    side and you are done removing the
    waste.



    Your chisel needs to be either exactly
    perpendicular to the board, or at an angle which will give you more clearance
    in the middle of the cut, not less clearance. When the joint is
    assembled, you will not be able to tell if you have undercut the
    middle part of the tail. Waste left in the middle results in
    unsightly gaps after assembly.



    Take the time now to trim up the
    sawn edges of your tails with a chisel. The edges don’t
    need to be perfectly smooth, but they should be pretty straight. A
    fine saw or a knife can also be useful. If any of your tails ended up with wavering
    edges, straighten them up now.


    4.
    Cutting pins





    When you cut the
    tails, you were cutting at an angle to the grain in the wood.
    Cutting the pins is directly along the grain. This can be a
    problem, especially if you are using one of the very
    fine Japanese pull saws. To see why, you need
    to understand the difference between rip saws and crosscut saws.



    When you are cutting across the
    grain, the smoothest cut will be had with a saw whose
    teeth are shaped like tiny knives. This type of saw will cleanly
    sever the wood
    fibers. Crosscut saws have teeth
    shaped like knives.



    When you are cutting with the
    grain, a different shaped tooth is needed.
    . If your saw teeth are knife shaped (crosscut), the saw
    is going to follow the wood fibers. To allow the saw to be
    guided, a chisel shaped tooth works best. Saws with
    chisel shaped teeth are called rip saws. When you cut the pins, you are cutting
    in the same general direction as the grain, but probably not exactly the same.



    Japanese back
    saws have teeth which are extremely knife shaped. This
    makes them very difficult to guide in cutting pins. (There
    is a type of Japanese saw intended for ripping, but it is not very
    common.) Small European style back saws have teeth which are sort of
    a hybrid between rip and crosscut. European style back
    saws work well either crosscutting or ripping. If you are unsure of
    your saw, try cutting a
    scrap of hardwood along a line just
    slightly off of the grain direction
    and see how well it works.



    Finally you can start on the pins. First you
    need to mark them on the piece of wood you are working on. The
    marking is done using the mating piece of wood as a
    template. There are a lot of ways of doing
    the marking. I will describe the approach I use,
    which works well for me.



    Clamp the piece of
    wood which is getting the pins cut into it in the vise, pin edge up.
    Raise the wood a small amount (1/16”) above the
    bench surface. Lay the mating piece of wood on
    top, aligning the reference edges. Try to put the bottoms of the
    tails (end grain) just over the inside edge of the pin board (did you check to
    make sure you know which is inside and which is outside?). You
    can judge the edge location by using a knife blade as a sort of
    feeler gauge. Alignment is very critical.
    Now place a large weight on top of the tail
    piece of wood. It is critical that neither piece of wood moves
    during the marking. Check your alignment again.



    Using a very sharp pencil or a
    sharp knife, mark the pins using the holes in the tail
    piece as a template. You must be careful to put
    the mark at the very edge of the tail
    holes, but you must also be
    careful not to push the tail board and move it. A
    knife works well here as you are marking in end grain,
    but you must be careful not to shave off the bottom corners of the
    tails!



    Another thing which you must be very careful
    about is how you mark the pins out on the opposite end of
    the board you are working on. There
    is only one right orientation for the two ends. You want to end up
    with a box, not a zigzag of boards. Pay close attention
    to which face is inside vs. outside and make the inside face the
    same for both ends of the board.



    Once you have marked all of the
    pins, slide the tail piece of wood away from the pin
    piece. Immediately mark both edges to indicate that these two and no
    others go together, and also indicate which face is
    inside and which face is outside. I often make cut marks with a narrow chisel
    inside the pins and tails. You can easily make a line, a cross, a star, and a
    hatch mark (1, 2, 3, 4 cuts). Put the marks where they
    won’t show in the finished work, but not in the waste. While
    the two boards are in close
    proximity, cross out the waste portions of the pin
    board. It is much easier to mark the waste correctly if the tails
    are sitting right next door.



    Now put the tail
    board out of the way, and raise the pin board
    high enough in the vise to mark the face and to saw. Using
    a square, extend the lines you drew on the end grain down one face
    to the scribe line. A pencil works best here since you are drawing with the
    grain.



    Now saw the
    pins. Your saw must not cut inside the lines. Cut so that the saw kerf is entirely in the
    waste. If you come inside the lines into the pin, you will have a
    gap. How close you come to the line depends on how good you are at marking and
    sawing. The closer you can come to the line (i.e. the more practice you
    have), the quicker and easier dovetailing will be for
    you.



    As with the tails, saw starting on the end
    grain to make a shallow groove, then angle the saw around to make a
    groove part way down the face. Work the cut
    down to just a saw kerf above the scribe lines on
    both sides of the board. Once you have all of the cuts
    down to the scribe lines, you
    remove the waste with a chisel just like when you cut the
    tails. Be careful of the fact that the pins are wider
    on one face than the other.


    5.
    Fitting





    Fitting is difficult at
    first. Your goal is to shave away at the
    places on the pins where there is too
    much thickness, until they
    exactly fit the holes between the tails. You should take
    your time, making fine shavings with a sharp chisel, and frequently checking
    the mating pieces against each other. If you prefer a file or rasp, by all
    means use it. Shave the tails as a last resort, as I find shaving
    the tails is a good way to make a mistake. The
    more dovetails along a corner, the more difficult the fitting.



    The ideal fit that
    you strive for is one which you can assemble and
    disassemble without using a mallet (just barely). It is terribly easy
    to damage your wood surface with a mallet. The fit I
    usually end up with needs light mallet work to assemble and
    disassemble. If you experience any resistance to
    assembly, try coating one side of the joint with chalk on
    the rubbing surfaces. Partially assemble the joint, and
    the chalk will mark the high spots you need to work on. You can also look for
    shiny spots on the pins (compressed areas) to indicate high spots.



    Some books will recommend a
    tighter ideal fit, on the assumption that the pins and
    tails will slightly crush each other on assembly and fit each other better as a
    result. I have used this approach with good success in soft woods like pine and
    cedar. I would not recommend using a this approach in hard woods, as it is too
    easy to split something. Cherry in particular is a bit brittle and you must be
    careful not to have too tight a fit.


    6.
    Gluing





    Before you glue, take
    time to think about how you are going to finish your
    boards. You probably want to fine sand the inside pieces before
    assembly, and you may want to finish the insides of the boards
    before assembly, depending on how you are planning on finishing your
    wood. I usually do not finish before assembly, but I
    am less picky than a lot of people.



    Before you glue, clear your bench
    top. Place within easy reach a square, all of the clamps
    you own, cardboard to pad the clamp jaws, towels, a
    mallet and a scrap block of soft wood to shield your mallet blows. It is
    probably a good idea to get someone to help you the first time you glue up a
    box. I usually use yellow (aliphatic resin) wood
    glue. If you have a complex assembly or
    have not put many joints together before, use
    white glue. White glue is not as strong as yellow
    glue, but it takes longer to set up.



    If you are making a
    box, you must glue up all of the corners at
    once to make sure everything is aligned. Apply
    glue to all of the hidden surfaces of one joint on at least
    one piece of wood. Some books recommend applying glue to both
    pieces, but I worry about the extra time taken
    allowing the glue to start setting up before assembly is
    done. This can be pretty messy, and you must be careful
    not to get glue where it doesn’t belong. Work
    efficiently, and try not to panic. Assemble each joint
    before applying glue to the next one.



    If you
    should still be assembling your
    corners when the glue starts to set, please
    don’t panic. Glue which is just starting to set is really not a
    problem if you deal with it in the right manner. Do not
    use your mallet to persuade a joint which is
    setting. Glue which is beginning to set
    responds best to steady pressure, not impulsive pounding.



    After all of your corners have
    been glued and assembled, check your corners for squareness. Put
    pipe clamps around the outside of the joints to snug up any remaining gaps in
    the dovetails. Watch where you put the clamp jaws as your
    pins and tails should stand just a bit
    proud of the surface. Adjust the tension on the clamps
    gradually to square up the box. Your box will
    probably not be perfectly square; reach a compromise
    between the wood and your pride. Let the glue set overnight.



    The next day remove all of the
    clamps. The protruding ends of the
    pins and tails can best be made flush with a
    block plane. Now is also a good time to work carefully with a plane
    to make the edges of adjacent pieces of wood meet exactly. Set your plane really
    fine and be careful not to tear up the opposite piece.



    Break all edges of
    your assembly with a block plane or fine sand paper. You
    will never see the difference, and your work will be much more
    comfortable to hold. If you use a plane, be careful to work both
    ends against the middle. Now is a really bad time to tear out part
    of an edge.


    Miscellaneous
    Comments





    When you are making a
    box, you must decide
    how to attach the bottom at the
    beginning. One method is to cut a groove the same size as the bottom
    thickness on the four sides of the box, so that the bottom is raised from the
    lower edge of the sides. If you are making conventional through
    dovetails, the groove must stop before it reaches the edge of the
    board or it will show on the outside. Cutting a stopped groove is
    difficult with hand tools. A better solution is to cut the groove all the way
    to the edge of each board and put a mitered dovetail over it. Look at a picture
    of this joint in a book to see how
    it is done. It is not too hard, but
    takes a little practice. The grooves should allow the
    bottom some room side to side for expansion and contraction. Be sure that the
    grooves on each of the four sides all line up with each other when you fit the
    dovetails together!



    Assembling
    a box with a grooved bottom
    is only a little bit trickier than
    a dovetailed frame with no bottom. Assemble two of the
    corners, then slide in the bottom and assemble the last
    two corners. Do not glue your bottom in place.
    Gluing this joint would result in cross grain construction. Leave the
    bottom floating so it can expand and contract without stressing your joints.



    A very elegant
    addition to a box is a shaped footing. This is
    really very easy to do if you use the right sequence. Cut a groove for the
    bottom a couple of inches above the edge of the boards. After the
    groove is finished, draw a pretty curve on the couple
    of inches of each board below the bottom and saw out your
    footing.



    You can make the footing a separate frame
    (from the main box frame). This short frame needs to be larger than the box,
    and has a groove cut around the top edge just large enough for the box to drop
    into. The two end up getting glued together. If you make the groove around the
    top edge of the footing tall enough, you don’t need to stop the groove you cut
    in the box to hold the bottom. Run the bottom groove all the way to the edge of
    the board, and let the footing cover it.



    There is another way to attach
    the bottom with a separate footing piece. Assemble and glue the four
    sides of your box. Cut a bottom board the same size as the outside edge of the
    box. Make a small four sided frame (dovetailed, of course), larger than the
    outside edge of the first box. This will turn into a footing. Cut curves in the
    edges to decorate. Before you assemble the footing frame, cut a groove along
    the top edge deep enough for both the bottom and the main box to drop in. The
    bottom will be supported by the frame, and the box will sit on top of the
    bottom. Both the bottom and a piece of the box need to drop into the groove. Remember
    not to put glue on the bottom or you will end up with cross grain
    construction. The frame needs to fit the box fairly well. You may want to cut
    the groove with two steps, so that the bottom sits in one, and the box sits
    above the bottom in the other step. This will help in keeping glue away from
    the bottom.



    A very nice way of
    assembling the legs of a small table with a
    central pillar is to install the legs with
    sliding dovetails. These are pretty tricky to do right.
    Fitting is much easier if you cut your dovetails at a steeper angle than
    normal.

      Current date/time is Mon Nov 19, 2018 2:12 am