Archive for the Category ◊ Techniques ◊

Author:
• Sunday, May 11th, 2014

shooting glove

Shooting is a gateway technique that produces reliable accuracy and control unattainable with machines. Here are three simple tips to improve your results with shooting.

1- Put a grippy glove on your left (non-dominant) hand

An inexpensive, widely available glove with a rubbery grippy palm adds remarkable strength to your hand. The work piece must be controlled with the left hand in two respects. First, it must not slide or pivot during the cutting stroke of the plane. The torque can be considerable with a wide work piece of dense wood. The glove gives you control with much less effort than a bare hand.

Second, in preparation for the cut when shooting end grain, the work must be advanced a tiny amount along the fence toward the plane. Without this, the blade edge will simply clear the work piece because it has already cut away the previously projecting thickness.

Practically, the work piece is advanced just to meet the toe of the plane sole, as in the photo below. This is done almost without thinking but it is a precise move made more controllable by the gloved hand.

registering the board

2- Simple microadjustability

Everything is not square in woodworking, even when we intend it to be so. For example, when fitting a drawer front to its opening, the sides of the front piece should be made to match the opening, even if it is a bit out of perfectly square.

To minutely adjust the shooting angle away from 90°, just place a piece of blue tape at the appropriate end of the shooting board fence. Realize too, that the angle can be adjusted with phenomenal precision by slightly altering the position of the tape.

microadjustability

Of course, this is done empirically, but for some mathematical fun, note that a .003″ thick tape placed at the end of a 7″ fence will change the angle .025° from 90°, and moving it to the 6″ position will adjust that new angle, in turn, by .004°. Using a .001″ plane shaving would create an initial adjustment of .008° from 90°. Shims are magic!

3- Hold the plane like you mean it

Whether you have a dedicated shooting plane like the #9 I use, or use a nice heavy bevel-up bench plane, or, yes, a bevel-down bench plane, grip that righteous beast over the blade. Get the big muscles at the base of your thumb firmly down on the sidewall of the plane, wrap your fingers around into the throat of the plane, and plant the ends of the fingers on the lower part of the lever cap. That way, you can control the ride of the plane on the horizontal track while keeping the sole tight sideways against the vertical runner.

grip the plane for shooting

Furthermore, you get a good tactile sense of the blade’s cutting action. In concert, all of this promotes accuracy by preventing the plane from tipping in any direction as it takes a firm, uninterrupted stroke.

I like the “hot dog” attachment from Lie-Nielsen on the #9. This is something I imagine could also be readily made by the user.

hot dog attachment

Category: Jigs and Fixtures, Techniques  | Tags:  | 5 Comments
Author:
• Wednesday, April 02nd, 2014

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This is so easy. Shooting is a fast and accurate method for making a straight and square long grain edge on small boards, generally less than about two feet in length. This is far easier, especially for thin stock, than planing the edge while the board is held vertically in a vise.

Though shooting is mostly associated with truing end grain, I really don’t know why long grain shooting is not commonly discussed in instructional materials. True, it’s not absent but I think it should be included among routine methods.

A long shooting board is helpful for this work. The long grain edge of the work piece should overhang the edge of the platform by a half-inch or so (see below), while the end is butted against the fence. For narrow pieces, especially a series of them such as drawer parts, I clamp an auxiliary bracing piece of plywood or MDF onto the shooting board platform, as in the top photo, to help my left hand steady the work piece.

The plane does not contact the vertical running edge of the shooting board platform that is used for end grain shooting. You simply control the plane to produce a straight edge much as you would when planing with the sole down – initially emphasize pressure on the toe of the plane, transition to balanced pressure, and finish with pressure on the rear portion of the plane.

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I like my Lie-Nielsen #9 for most of this work, but really any bench plane, bevel-up or bevel-down, with a length appropriate for the work, will do. The “hot dog” handle on the #9 is very helpful to control the plane in all directions. Placing my fingers on the lever cap gives a good feel of the blade’s cutting action. When using a regular bench plane, I like to grip the arch in the sidewall of the plane and place my fingers over the lever cap. The contour of the Veritas bevel-up jack plane makes it especially effective to place the heel of the hand on the rear of the sidewall arch.

Medium to larger work is more easily and accurately managed by clamping it to the work surface. This prevents the work piece from yawing as you push the plane, which would make it difficult to produce a straight edge.

It is also possible to accurately set the auxiliary bracing piece, referred to above, to produce a parallel-sided work piece. This can also be accomplished by planing to a gauged line. No table saw is needed here.

A nice way to combine machine and hand work to make small to medium pieces with accurate and smooth edges, such as drawer parts, is to refine and smooth the machine-jointed edge by shooting. Then rip to width on the table saw with the planed edge against the fence. The ripped edge can be smoothed with one or two passes of a hand plane, usually later in the building process.

You can even eliminate the shooting board and still do this work. Just take a piece of 3/4″ MDF, clamp the work piece on top with its edge overhanging the MDF, and run the plane on the workbench top. If you don’t trust the trueness of your workbench, temporarily cover it with another piece of 3/4″ MDF.

This is also an easy, effective method to edge joint a pair of thin or small boards, such as drawer bottom stock (see below). Decide on the mating edges, “close the book” on the joint, clamp the pieces to the platform, and shoot both edges at once. It’s hard to miss.

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Shooting is also a sensible way to work with very small pieces (see below).

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These are effective methods that require minimal infrastructure and can be used regularly on a wide range of projects.

Category: Jigs and Fixtures, Techniques  | Tags:  | One Comment
Author:
• Thursday, March 27th, 2014

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Finer pitch saws generally produce more precise cuts than coarser pitch saws. Well, of course they do. The finer teeth make a cleaner kerf with which to track a line. They also advance the kerf more slowly and thus presumably more controllably since each stroke is a relatively smaller commitment that can be adjusted as needed.

The finer pitch, all else being equal, also produces a smoother sawn surface. Also, the thickness of the wood must be taken into account. At least several teeth should ride in the kerf to maintain control and prevent the saw from grabbing and tearing.

So, OK, we don’t use a 5 1/2 ppi rip saw to cut dovetails in 1/2″ stock, obviously.

But what may not be so obvious are the practical limits to fine pitch saws. In other words, finer and finer is not more and more accurate.

If each commitment – each stroke of the saw – is too small to judge whether accuracy is being maintained, then you have to wait for a few of them to really make a judgment. In other words, the feedback is delayed and you can be going off course without knowing it for a while. Similarly, the corrective action is harder to judge.

The object is to use a tool that is palpably controllable, not too coarse, of course, but also not too fine. Among novice woodworkers there is a tendency to think that using the finest saw available will be the most accurate way as long as one is patient enough, but for a saw, and probably for just about any tool, it might be too fine to function accurately. Note also that the stroke speed of a coarser pitch saw can be slowed to some extent.

As an analogy, a good car steering wheel should be responsive, not mushy. The result of an input action – such as a saw stroke – should give a sufficiently sensible and prompt result so that the feedback loop is closed clearly and quickly. This is much of what hand tool woodworking is about. In other words, if you go too slowly, you can’t tell what you’re really doing!

In summary, consider balancing factors when choosing the pitch of a saw. And don’t be charmed by superfine saws (e.g. superfine dozuki saws) or see them as a substitute for skill; they may be too fine.

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Author:
• Sunday, January 26th, 2014

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Come on, woodworking isn’t really so hard to do. Just have all your stock flat, straight, and square, cut to the layout line, and never make a mental error. Everything will go just fine.

Just kidding.

But starting saw cuts accurately does help to make woodworking, especially joinery, go much better. “Well begun is half done” is true for this task. Accordingly, it is worthwhile to explore nuances of technique.

Laying the saw teeth on the wood and pushing without any guidance is generally too unreliable. So the left (free) hand is set on the wood and a finger, usually the thumb, contacts the saw plate above the toothline to provide stabilization.

This can be done with the thumb alone, but it is more stable when the side of the index finger is placed against the pad of the thumb while the hand rests on the work piece. However, the thumb pad tip is squishy, so it works better if it is also firmed by pressure from the index finger.

Even better is to angle the thumb a bit to the left so as to engage the hard thumbnail tip against the saw plate. The index finger acts to not only stabilize the set up but to help bring the saw teeth to the proper place to start the cut and fine tune the placement.

I find that using the thumb knuckle is less controllable since it is not on the most distal portion of the finger.

Below, with this angle of the thumb, only the soft tip will contact the saw plate.

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Below, I’ve re-angled my thumb so the nail will contact the saw plate. This will vary depending on the angle of the cut, sight line considerations, wrist flexibility, and even the length of the nail. In some situations, it may be too awkward or impossible.

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Is this getting too punctilious, picky, or perhaps persnickety? I don’t think so. These are the bits of technique that are not mentioned in books but can make a real difference in work. Though these finger configurations work for me, the key point is to work out the details to suit your hands and the circumstances of the task to achieve the control and ease that is part of good craftsmanship.

Category: Techniques  | 2 Comments
Author:
• Tuesday, December 31st, 2013

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How and where would you start this saw cut? Do you start at the near or far end of the board, or attempt to score the entire width on the first stroke? Do you drag your Western saw backward or push your Japanese saw forward to preliminarily score the wood?

This is no small matter. Accurately starting the saw cut is probably the most critical manual step in dovetailing, especially when sawing pins that have been laid out from previously cut tails.

Without a doubt, the smoothest and most accurate method for me is to slightly raise the handle of my Western push saw and start the rip cut at the far end of the board. A Japanese pull-cut saw would be started at the near end. This also works for the crosscuts at the sides of the tail board, as well as for sundry other woodworking cuts.

Though I am empirically convinced of this, let’s explore why.

As the saw teeth approach the top surface at the far corner of the wood with the saw handle raised, the rake angle is effectively relaxed (a greater “negative” rake), which makes for a less aggressive and more controllable entry into to wood. Approaching from the near corner (with the saw handle lowered) would effectively increase the rake angle, creating a positive “hook” rake, which is aggressive and tends to catch and jump on all but the softest woods.

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Now, the degree to which one should raise the handle varies with the saw, the wood, and personal feel. If the saw is held too flat on the wood, it may skid on the end grain as you try to engage too much wood at once. Held too steeply, the saw tends to catch the far corner of the wood. Goldilocks this – experiment with your saw and the particular wood at hand. A generally light touch, letting the saw do the work, is part of all this, of course. Bad Axe saws may come filed with a helpful relaxed rake at the toe, which must be taken into account.

As a bonus, this method, applied to either Western push or Japanese pull saws, deposits the sawdust away from, not into, the line that the saw is advancing upon.

Some woodworkers like to start a push saw at the near end, reasoning that this pushes down the fibers, much like planing with the grain. I find that factor is outweighed by the rake factor, making that approach less reliable for me.

Likewise, I find that starting the cut by dragging/pushing the saw opposite to its normal cutting direction tends to make the saw skid and creates a kerf with a scalloped bottom that tends to catch the teeth when they are then propelled in the normal direction. It seems to me a generally mushy technique that is unnecessary with a good quality saw.

When we start a usual rip or crosscut on the flat surface of a board held horizontally, knee on the board, we are doing much the same as starting the dovetail cut in the manner that I prefer, though with a more aggressive angle, and the added advantage of sawing the fibers “down” when ripping. In fact, some people like to start the dovetail cut at the near side of the board with the saw held at an extremely low angle simulating ripping a board with a big ripsaw. The problems with that, in my opinion, is the business end of the work piece must be less rigidly held quite far above the vise jaw, and you have to start by following two lines at once.

The key point is to recognize the importance of a good start to the saw cut, experiment, and find what works best for you. Much of good craftsmanship is built on recognizing and managing the critical junctures of procedures.

And that, of course, leads to happy woodworking.

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Category: Techniques  | 3 Comments
Author:
• Tuesday, November 19th, 2013

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One of the most difficult aspects of learning and refining craftsmanship is understanding and sensing when something is just enough and not too much.

Consider sharpening a plane blade: sharper is better, at least within a practical range. However, the camber in the edge is a subtle quality – too little and too much are both detrimental to function. The craftsman must understand the purpose of camber for the particular type of plane at hand, as well as have a visual and tactile sense of when the amount is good.

In drawer fitting, proper preparation of the carcass is essential to good results. For this, we must go beyond the simplistic idea that it should be as square as possible, if for no other reason than achieving perfectly square is impossible, and thus we must understand how to bias the imperfection.

It will be much easier to fit a fine drawer with a nice action if the carcass interior is a bit wider at the back than at the front. It must never narrow in width toward the back. Different carcass types – solid wood, frame and panel, a table with drawer guides, etc. – will dictate different ways to create this adjustment, but there is always a way.

We are faced with the matter of “a little bit.” It is sweet for a drawer, especially a smaller one, to have an easy pull to start, then tighten against the sides of the opening as it is almost fully withdrawn. Conversely, it is a sour drawer that gets pinched at the back as it is almost fully pushed in, while the front is excessively loose in its opening. It just doesn’t seem happy to be there.

In building a small jewelry chest of drawers with a solid wood carcass with an opening about 16″ wide and 11″ deep, I incorporated the necessary tweak by shooting the end grain of the top and bottom pieces slightly out of square. I would not normally measure the amount. Instead, I work by feel and eye to get a sense of just enough width that will allow the drawer to move unencumbered in its housing after an initial struggle to enter it.

“But Rob,” you say, “enough is enough already! How much?”

OK, OK, I measured it using shims. The sides are each out of square by about 0.007″ over the 11″ depth, for a total difference between the front and back interior width of just under 1/64″.

More important, I think that will be just enough but not too much.

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Pictured above: a direct comparison between the front and back widths.

Category: Techniques  | 4 Comments
Author:
• Thursday, October 17th, 2013

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This will start a few posts here on sawing tenons by hand, but first let’s first ponder the mortise and tenon joint in general. A joint that has been used successfully for thousands of years certainly deserves some thought.

What accounts for the joint’s legendary strength? Imagine trying to snap an “L”-shaped M&T construction. The mechanical lock of the tenon shoulders meeting the wood surface around the mouth of the mortise effectively transfers the imposed stress to the glued surfaces of the tenon cheeks against the mortise walls.

The stress on the glued surfaces, in turn, is a shear stress – and we know how wonderfully glued wood surfaces resist shear stress. Voila: a strong joint!

In fact, rarely will a reasonably made M&T joint itself fail. Rather, it is the wood around the joint that is more likely to give way.

Looking at the mortise and tenon strength tests detailed in Fine Woodworking magazine issue#203 (February 2009), we can see that it is almost always the wood around the mortise that failed, even when the tenon itself was too weak to hold up. In the real world, I cannot recall seeing any decently made tenon break, but I have seen the wood around the mortise fail.

I also observe that the only real danger to a tenon pulling out in a properly made joint is from the all-powerful forces of hygroscopic wood movement conflict. This may produce some gapping at the shoulder line, especially in injudiciously designed joints.

In most woodworking instruction, much attention is paid to proportioning the thickness of the tenon with respect to the thickness of the rail. Recommendations are typically that the tenon should be 1/3 – 1/2 as thick as the rail itself.

Yet, knowing from where the M&T derives its strength and how it is capable of failing, it behooves us to look at the proportions of the joint as a whole:

  • Especially consider the robustness of the wood surrounding the mortise.
  • Consider the area of shear-stress glue surface – the tenon cheeks.
  • Consider the nature of the dimensional conflict within the joint. The corollary here is that glues with a bit of give, like PVAs, have an advantage.

One more possible consideration is the lever arm force exerted on the stile (mortise member) by the tenon. In the FW article, look at how the humble stub-tenon and biscuit joints failed: the stile split along the grain near the end of the tenon depth. That’s a lot harder to do with a deeper tenon where the leverage works out to be not as lopsided, and the tenon engages more peri-mortise wood, not to mention the direct value of the greater glue surface area.

I hope, readers, you are not now expecting me to delineate a set of rules for proportioning a good M&T joint. Sorry, there are simply too many construction situations and circumstances. However, thinking clearly about what is going on in the joint and the considerations listed above should bring you to good joint designs. Furthermore, frankly, there is a good amount of slack here – even non-ideal but more-or-less reasonably designed M&Ts will hold up.

But don’t make a sturdy 3/8″ thick tenon to sit in a mortise with a 1/8″ outside wall!

Coming up: sawing tenons by hand, starting with sensible joint layout.

Category: Techniques  | 2 Comments
Author:
• Thursday, September 19th, 2013

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The previous post discussed the creative destruction that I optimistically think contributed to my development as a woodworker. Thus, probably slower and with more angst than necessary, I think I’ve learned a few things worth sharing. Surely, readers, you have many points to add, but here are some key factors that come to mind that I believe contribute to a successful woodworking project, which, for me, is one that brings the “quiet joy” of which Krenov spoke.

  • Plot a smart order of construction steps. Don’t back yourself into corners that make succeeding steps more difficult than they need be. Think and think ahead.
  • Recognize appropriate tolerances in stock preparation, joinery, tool tuning, and so forth. Know where you must be very close and where you have some room. We all recognize the damage caused by sloppiness, but compulsive attempts at unnecessary perfection waste energy when building.
  • Know where the critical junctures are in the process. Some steps are make-or-break, so bear down on these.
  • Likewise, be cognizant of the major pitfalls. Usually, they are apparent only if you stop and think.
  • When possible, work in a self-correcting manner. For example, it is often a waste of time trying to get two surfaces to meet right off, and easier to plane small excesses flush as a final step.
  • There are many small touches that cannot be shown in the shop drawing, such as how ends and edges are softened. These decisions properly come along as the work progresses, but they must be consistent with your style and the design concept, and so you must maintain aesthetic awareness as you build.
  • Choose finishes as part of the design, not as an afterthought when the piece is assembled. Experiment on scrap to find a finish that supports the design concept.
  • It is nice to challenge yourself, but not to the point where you cannot maintain reasonable composure as you build. That’s no fun, and the piece will probably show it!

In marked contrast to the disappointment that can sometimes come from trying to make fine things, it can be exhilarating to work in control, in the flow, and in the moment, making something that you dearly want to be.

Here are best wishes as you pursue your path to the joy of woodworking.

Category: Techniques  | 5 Comments