Lost Art Press

Author: meghanlostartpress

Add a Shaving Horse

Posted on by meghanlostartpress
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Early shaving horse. This horse is featured in the 1561 book “De Re Metallica” (“On the Nature of Metals”) by Georgius Agricola.


This is an excerpt from “Ingenious Mechanicks” by Christopher Schwarz.

Many visitors to my shop are intrigued by the low Roman-style workbenches (especially the children, who play Whac-A-Mole with the pegs). The most frequent questions I hear are: Were the Romans Lilliputians? And is this low workbench where the shaving horse came from?

It’s impossible to know for sure. But it is a short intellectual hop from a workbench you sit on to a shaving horse. And because there are so many variants to the Roman-style bench – for shipbuilding, steam bending, wagon building and on and on – the shaving horse might just be one of the many flavors of the low bench that developed for the specialty trades.

A small breadcrumb of evidence is the 1561 woodcut in book five of “De Re Metallica” (“On the Nature of Metals”) by Georgius Agricola. In the image, a German woodworker is shown shaving a stick to a fan shape so it can be used in a mine. Miners would use these dry sticks to help dislodge the ore they were seeking. The fan shape made the sticks easy to light on fire.

The first time I saw this woodcut, my brain saw a low Roman workbench instead of a shaving horse. Perhaps you can see the same thing I did – perhaps not. In any case, this image inspired me to add a removable shaving horse to one of my low benches.

The type of shavehorse shown in “De Re Metallica” is called a “dumbhead” or “Continental” style. These shavehorses have the pivoting clamp in the center of the bench and you squeeze your work either to the left or right of the clamp. The variation I built is commonly called an English shaving horse, which appears much later in the visual record.

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An easy accessory. Adding a shaving horse to a low workbench takes about a day. This one was made using oak scraps (hence the different species) that I pulled from my burn pile. Photo by Narayan Nayar. 

Instead of a central pivot, the English shavehorse has two arms on the outside of the bench.

I’ve used both styles (including the mutant Shave Pony), and I decline to participate in the Shavehorse Holy Wars. I chose the English style because it is the style I have used the most and it was the easiest to adapt to an existing low workbench. All credit is due to Jennie Alexander for introducing me to this style of horse through her writing.

Here’s how it works: It starts with a 2″ x 2″ x 8″ post that is friction fit into the mortise that also holds the workbench’s planing stop. That post is joined to the “stage” of the shavehorse (the work surface of the horse). The two pieces are joined with a 5/8″-diameter dowel, which allows the stage to pivot up and down – just like the leaf of a hinge.

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About right. I like to have the workpiece right above my belly button. I found that position and noted the distance between the benchtop and the bottom of the stage.

Below the stage is a large wedge-shaped assembly, called the “chock” by Alexander, that looks a bit like an odd drawer. This assembly is not attached to either the stage or the workbench. Moving it forward and back moves the stage up and down so you can clamp workpieces both small and large.

The clamping action is controlled by the arms. The arms pivot on pegs, which are inserted into holes in the edge of the benchtop. Between the two arms are the foot pedal and the head of the shaving horse. You press the pedal at the floor, and the head (sometimes called the “yoke”) clamps the work to the stage.

This horse can hold both short spindles and long legs. While it looks like long workpieces might hit the benchtop, you can simply knock the 2″ x 2″ post up an inch or so, and the work will clear the benchtop.

— Meghan B.

Special Dovetails

Posted on by meghanlostartpress
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FIG. 1. A COMMON ERROR. No allowance has been made for the rebate which runs right through and forms a gap.

This is an excerpt from “The Woodworker: The Charles H. Hayward Years: Volume III” published by Lost Art Press. 

The through dovetail is straightforward enough to cut, but sometimes there is a slight complication owing to there being a rebate at the edge, or because a mitre is desirable at the corner. There is nothing complicated about it, but it is easy to make a mistake if it has not been within your experience before.

Consider the case of a tray or drawer which is to have its corners through dovetailed together, but with a bottom which has to fit into a rebate. If you cut the normal simple dovetail you will end with the unfortunate result shown in Fig. 1. The rebate, being worked with the rebate plane, has necessarily to be taken right through, and this leaves a gap at the shoulder.

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FIG. 2. TOP SHOULDER CUT INTO THE REBATE.

One way out of the difficulty is to set the dovetail in an extra amount to allow for the rebate depth, and make a square cut on the dovetailed piece (not on that with the pins) level with the rebate. The shoulder is then allowed a projection so that it reaches into the rebate as shown in Fig. 2. Note that no cut is needed on the pins since the rebating automatically removes the wood.

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FIG. 3. SQUARE MEMBER FILLS IN REBATE.

Alternatively the method in Fig. 3 can be followed. Here the top square cut level with the rebate is made as before, and the corresponding cut is made on the pins, but only down to the rebate. It is thus necessary to gauge in the extent of the rebate first so that the cut can be stopped short.

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FIG. 4. MITRED SHOULDER. A REBATE COULD BE WORKED DOWN TO THE MITRE DEPTH

A third method is to use a mitre. This is of special value even when there is no rebate because it gives a neat finish; also because it enables the edges to be rounded over as in Fig. 4, or to be moulded. The joint when there is a rebate is similar to Fig. 4, but the depth of the mitre should equal that of the rebate. Note that there is a square cut level with the rebate on the dovetailed piece, and that this is transferred to that with the pins. It is not cut right through, however (see Fig. 4) but is only cut at the inside at 45 deg. (that is, as far down as the mitre). When cutting the mitre hold the saw on the waste side so that the line is just left in.

— Meghan B.

Finishing Your Chair

Posted on by meghanlostartpress
Chairmaker's-Notebook
The surface patterns of the raw wood can overwhelm the subtleties of the forms.

This is an excerpt from “Chairmaker’s Notebook” written and illustrated by Peter Galbert. 

Paint has come a long way from the toxic lead paints of the original Windsors to the stringy enamels of the 20th century. I paint my chairs with milk paint, and while it was not the traditional finish for Windsors, it does a great job of coloring the wood without obscuring the texture. One problem with milk paint is that its manufacturers tend to describe mixing and using it in a way that creates a crude “country” finish. I don’t want this for my chairs, so I mix the paint thinner than recommended and follow a multi-coat process to get the refined look I want.

When done properly, the grain and texture of the wood are clearly visible, and the desirable tool marks and edges are sharp and crisp. Not only is the warmth and depth of the wood present, but it is deepened. Over time, normal use will wear the paint, exposing the edges of the chair and highlighting the shaping. The overall effect is far more striking than one dominated solely by the surfaces and colors of the wood.

Before launching into surface and paint preparation, I feel compelled to talk about samples. Committing making sample boards might just be the toughest lesson in all of woodworking. But until you have a sample – and I mean a completed sample – that you are pleased with, it is more than likely that you will be disappointed in the results on the actual piece.

When working with a new finish, I make samples on the various woods and surface preparations of my piece. I observe all the normal drying times, steps and layers. Lots of notes will help you remember the steps and measurements. Once I love the results, it’s time to work on the actual piece.

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Wetting scraped and sanded areas raises the compressed fibers.

Surface Preparation
Surface preparation is vital to getting good results. Any surface that was shaved with a sharp blade, such as a drawknife or spokeshave, is ready for finishing without any further preparation – save making sure that it is free from dirt or grime. This is because the cutting action shears the fibers cleanly without compressing the grain. Even parts that have been put through the steamer will show no raised grain where they were shaved with a sharp tool.

Areas that have been scraped and sanded will have some degree of grain compression that will show up as raised rough fibers on the surface once they contact either water, water-based stain or water-based milk paint. For these areas, I sand to #220-grit, then wet them to raise the grain. This is often easier to do before assembling the chair.

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Most surfaces on the oak can be finished with spokeshaves, leaving an inviting faceted surface, ready to finish.

It’s important to let the surface dry and harden; letting it sit overnight is best. Then I lightly sand with #220-grit paper, being careful not to apply too much pressure. Instead, I let the sandpaper cut the fibers with multiple light passes. These areas will most likely show raised grain again, but I sand them after the first coat of paint has soaked into them and hardened the fibers. One sanding after the first coat of paint is usually enough, but I inspect those areas carefully to ensure that I am happy with the surface after paint is reapplied.

 My turnings in the undercarriage are finished with a skew, but because any burnishing that takes place may resist the paint sticking, I sand lightly with #320-grit while the piece is on the lathe. Be sure to remove the tool rest and any loose clothing before sanding. I also wear a respirator because the fine dust is dangerous. There should be no surface preparation required after that.

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Rinsing the seat with naptha cleans the surface and can reveal surface quality.

The seat is perhaps the most critical place for surface preparation. Pine tends to compress when scraped, and it might also contain considerable sap or pitch. It is difficult for paint to adhere to sap, so I heat the surface of the seat with a heat gun until I can see the pores with sap in them liquify. Then I rinse the seat with naptha or grain alcohol. Always wear gloves when handling solvents. I repeat this if the seat seems quite pitchy. Some manufacturers suggest sealing the seat with a coat of shellac or using an acrylic additive to the milk paint to encourage solid adhesion. I have done both, but have found that the brand of milk paint that I use, from the Real Milk Paint Company, doesn’t require help sticking to the surface. If I do use an additive, I only use it on the first coat on the seat and nowhere else on the chair.

If your chair has been sitting around for a while unpainted, oxidation and dust will have contaminated the surface and you might consider wiping the whole chair with solvent such as grain alcohol or naptha before painting.

— Meghan B.

Chairs by Jonathan Fisher

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The affordability and simplicity of the slat-back chair made it a favorite form in 19th-century New England.


This is an excerpt from “Hands Employed Aright: The Furniture Making of Jonathan Fisher” by Joshua A. Klein.

The first chair Fisher recorded making was in December 1802. This “small chair,” probably for children, seems to have been a trial run for him because a couple weeks after its completion, he began to equip his work shop for a more efficient workflow. He “made a rack (a bending form) for chair backs.” And “made a shaving  [?] jack” (probably his shaving horse). With these two appliances, Fisher could refine his chairmaking process by “[making] several chair frames” before undertaking the production of a set of “kitchen” chairs in 1805.

Nancy Goyne Evans’s research into the New England usage of the term “kitchen chair” has shown that it refers to a slat-back side chair.  Fisher’s documentation of the construction of these chairs concurs with that assessment.

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The flats on the sides of the tenons ensured that when the legs shrunk, they would not split.

February 1805 he made four “little” chairs probably for his four children who would need them: Jonathan, Sally, Betsey and Josiah. Having his children’s sitting needs taken care of, he set out to build the full-size versions. The first one he made that March did not work  out well. “Worked upon a chair; broke it putting it together. Began another.” This comment is interesting because it suggests that the method of assembly Fisher used to make his chair required significant force such  that there was risk of completely ruining it. When driving the tenons of the rails and stretchers in the “green” legs, it was common practice to make the fit incredibly  tight. This way, when the leg dried out, it would pinch the tenon from coming out. Having not yet developed the feel for “how far was too far,” Fisher perhaps fractured one or more members.

The slat-back chair (Cat#16, p 161) in the Fisher collection shows evidence of this kind of assembly. The tenons all have small flats carved on their sides. This technique was a way to remove material on the legs’ cross-grain direction while allowing the top and bottom of the tenon to be oversized when driven in. If the orientation of the flats were reversed (meaning on  top and bottom), the driving would split the leg due to the extra thickness of the oversized tenon running cross-grain. This is perhaps where Fisher made his early mistake. The method appears to work incredibly well because although the only pins in the entire chair are in the top slat, it has no wiggle whatsoever – pretty amazing for a 200-year-old chair.

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This stout rocking chair was once painted red and had a woven seat. The tablet crest, although unusual for this form, appears to be original to the chair.

Fisher’s shop work during this time on chairs seems a little more focused than usual. Although he made a few visits and “wrote upon sermons” like always, he set aside a surprising amount of time to this batch of chairs.

Tuesday, April 2, Fisher recorded many of the steps of the chairmaking operation: “Primed some chairs. Went into the woods and cut a little chair stuff. Turned posts and put together a kitchen chair.” During the ensuing weeks of construction, we learn that he “hewed out [his] posts” before turning them. He may have also used his “shaving jack” for further shaping but only ever recorded using it to “shave … chair backs.” Interestingly, there is a comment on April 19 about “sawing out a few chair backs.” Typically “sawing out” refers to resawing rough material. So it appears that rather than rive backs from the log, he preferred to saw them.

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The red paint is clearly visible on the seat rails.

After they were assembled, he painted the chairs, probably with the “1-1/2 gal. oil, 5 lbs. yellow ochre, 5 lbs. red ochre, 1 lb. patent yellow” he purchased from Mr. Witham’s store at the head of the bay during the construction process.

The “bottoming” (seat weaving) of Fisher’s chairs always appears to be connected to the pounding of “basket stuff.” The fact that he didn’t mention weaving baskets after the prep work but instead immediately began weaving the seats seems to imply that they were woven of wood strips rather than the twisted rushes one would expect in northern New England.

— MB

Bending Wood for Chair Parts

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This is an excerpt from “Welsh Stick Chairs” by John Brown.

I disagree with people who say wood should be partly seasoned for steaming. The best would be ‘cut down yesterday, steam today’. Anyway, as soon as this ash is cut up it starts to dry. The moisture is sap. I drive it home and put it in a butt of water. Then I get my steamer rigged.

Two steamings a year supplies all the bends I need. My steamer consists of a 6′ length of heavy cast-iron pipe, 6″ internal diameter. At one end is a good fitting elm plug with a 1 ⁄2″ hole through it, in which is a copper tube. There is a wooden frame to support this end of the pipe and a pair of ‘scissors’-type gallows to hold the other end. The copper pipe leads into a 2-gallon stainless steel tank. (The tank came from the inside of a liquid vending machine and it is a pressure vessel.) For heat I use a trusty primus stove. The open end of the pipe also has a plug with a handle on it. I also have a small 1 ⁄4″ hole bored through this end with a removable wooden plug. I will explain why later. The whole pipe is lagged, sewn up in old rags and insulating material.

I start early on a steaming morning. Up at 6 a.m., fill the tank with water, light the primus. Everything must be ready and in its place, like an operating theatre. Forty ash sticks, pieces of string to tie round them so that I can pull them out, thick leather gloves, jigs for bending around, cramps, everyone I can lay my hands on, in fact no hold-ups. It’s like the morning of the big fight!

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I can get from five to seven pieces in the steamer, it depends how curved they are. Each piece has string which hangs down under the removable bung. Gradually, the whole contraption heats up. By lowering the outer end of the pipe I can drain off excess water, for until the pipe hots up, the first steam condenses. At this stage I leave the small bung, in the 1 ⁄4″ hole that I mentioned, out. Soon, say by about 7.30 a.m., a small jet of steam comes out of this small hole and I know we have ‘steam up’. The lagging of the pipe is so important. What is needed for bending is heat, wet, and pressure. Now I have worked out that if I remove the little plug from the 1 ⁄4″ hole and the steam shoots out 6″ or so – I have pressure!

How long should I leave these pieces in? Difficult to say. About two hours is the norm, but I have left them too long when they get soggy and lose all the natural springy wood-like qualities. Really they want the minimum time that will allow them to bend. There are as many different theories as there are stars in the sky about bending wood with steam. What works for you! Meanwhile, I must prepare my jigs, and have a set of replacement ash blanks ready. I don’t want visitors today!

My jigs are all sorts. The first one is a very fine piece of work. A 2″ piece of elm, looking not unlike a chair seat in outline, nailed to a larger piece of 2″ elm. Around the perimeter of the jig, and about 11 ⁄2″ out from it, are 3⁄4″ holes at 3″ intervals. The idea is to bend the arm around, putting .” dowels into the holes, and then wedging the arm tight to the jig. It takes longer to write than it does to do! I have about four different shapes, and these determine the type of chairs I make. As the year goes on I judge what I will need. Some jigs are old seats that were too hard to chop. I bore slots at intervals about 2″ in from the edge. In making jigs I have to overstate the curve a little, for like all things natural, wood tends to want to go back to where it was.

9.30 a.m. approaches. Jigs are all ready, the first one cramped solidly to a bench. After all these years, the heart still beats faster. On with gloves. If ever the proverb ‘make haste slowly’ applied it is now. Out with the bung, a rush of steam. Pull the string you want, holding hot ash in one hand, replace the bung. Dispose of string and look for centre mark on arm. Now, place it on jig, bang in dowel, and wedge, ease round, no jerks, dowel and wedge, round, dowel and wedge, then the other side, round, dowel and wedge, round, dowel and wedge … it’s there, o.k….no split-outs. The tone is set for the day. And so it goes.

I have steamed six and had one good arm, I have steamed six and had six good arms. I could get masterful results by using a strap contraption. This is a method whereby a thin metal strap is clamped to the hot arm, and it is then bent round the jig. This requires more accuracy than I use. The pieces must be an exact length to fit in the end blocks of the strap. My main objection to this method is that if the arm is going to break or shred, better it happens now than when the chair is in use. Remember those lovely Thonet bentwood chairs? The wood for them was bent in huge numbers. Heated in an autoclave, and bent, dozens at a time in hydraulic presses. I have rarely seen one without a sheer brake, or incipient brake. Steaming is an art; science and technology cannot do it. Sometimes, having successfully bent an arm, I get the next piece out, put it on the jig, start to pull and realise this piece is not ready, although steamed for an identical time, and I put it back in the steamer.

I leave the arms on the jig for a couple of hours until the next lot in the steamer are ready. Then I release them and tie a cord across the open end to maintain the bend. Until they are cool and dry they will not maintain their shape. Steaming vastly accelerates the drying process. The sap is all out, and only water remains. The residual heat rapidly dries them. In one month they are totally dry.

— MB