Lost Art Press

Reproducing and Using Moxon’s ‘Waving Engine’

Posted on by meghanlostartpress
Fig. 5.1 “Waving Engine” from Mechanick Exercises, Joseph Moxon, 1678–80.

This is an excerpt from “With all the Precision Possible: Roubo on Furniture.” It is a follow-up to the post from a couple weeks ago that described a “machine for making waves.” Below is a portion of an essay by Jonathan Thornton that was written after he made one of these machines based off of historical descriptions of the machine.

The book “With All the Precision Possible: Roubo on Furniture” is the result of more than a decade of work by an international team that produced the first English translation of the 18th-century woodworking masterpiece: “l’art du Menuisier” by André-Jacob Roubo. This translation covers Roubo’s writing on woodworking tools, the workshop, joinery and building furniture.

In addition to the translated text and color images from the original, “With All the Precision Possible: Roubo on Furniture” also includes five contemporary essays on Roubo’s writing by craftsmen Christopher Schwarz, Don Williams, Michael Mascelli, Philippe Lafargue and Jonathan Thornton.

Introduction
Anyone with longstanding interests in woodworking and the history and technology of picture frames could not help but be intrigued by the complex rippled mouldings that are most commonly seen surrounding paintings of the Baroque period. If that person is also a maker and collector of tools, as I am, then the construction of a device to make them is a strong temptation. It was years ago now that the temptation became almost an inevitability with my discovery of an engraving of such a device in Joseph Moxon’s seminal work on technology, “Mechanick Exercises.” 1 All I needed was the time, which was furnished by a semester sabbatical in 1994. I built a close reproduction of his device and have been exploring its capabilities as well as the literature on the subject ever since.

Moxon’s device intrigued me for several reasons: it was neglected or misunderstood in the available literature, it appeared that it would be capable of producing a variety of complex waveforms and it was the only type of such devices that to my knowledge had not been faithfully reproduced (although a somewhat modified version had been published in Fine Woodworking in 19862). The device, called the “Waving Engine” by Moxon (Fig. 5.1), works on a relatively simple principle. A stock piece is fastened to a guide or template rod carved into a waveform, and they are pulled together through a stationary cutter. As the guide rod rises and falls over a polished feeler bar, the waveform is gradually cut into the stock piece by a fixed blade. While the principle is simple, the devil is in the details.

Fig. 5.5 Overall view of a reproduction “Waving Engine” of the Moxon type. (drawing by Thornton)

Making the Machine
The illustration of the device that Moxon provides (from a plate almost certainly engraved by himself) presents a few problems of interpretation, and Moxon’s description, while fairly thorough, omits some important information. My intent was to make Moxon’s “engine” to his specifications, and if modifications had to be made, the reproduction itself would tell me what to do, and not my own second-guessing.

“The Waving Engine…hath a long square Plank…All along the length of this Plank, on the middle between the two sides, runs a Rabbet…Upon this Rabbet rides a Block with a Groove in its under side…the Groove in the Block is made fit to receive the Rabbet on the Plank.” (Joseph Moxon)

Fig. 5.6 Detail of pulling block and height adjust mechanism. (drawing by Thornton)

I made the plank from quartersawn sycamore. The rabbet I made from hard sugar maple, likewise the block that rides on it. This is the block that pulls both the patterned template and the stock piece through the cutterhead. Moxon attaches these elements to the block with a “Vice, somewhat larger than a great Handvice….” In considering this, I made the only major deviation from Moxon’s machine. I didn’t see how a fixed vice could easily follow the up-and-down motion of the guide rod (“rack”) and stock (“riglet”), let alone the gradual raising of these strips as the molding was cut. I suspect that simple looseness of fit allowed Moxon’s machine to accommodate these movements. In place of the hand-vice, I forged a tongue with a hinged box joint (mortise and tenon) much like the joint in a pair of pliers. The tongue would move to accommodate any adjustment upwards. The tongue itself was fastened into the block with a rod, which threads through it and also penetrates the block (at an angle — the purpose of which I will make clear). By means of this rod, I can adjust the attachment point to accommodate different widths of stock. In addition, I placed a support rod and knob under the end of the tongue and likewise threaded into the block, so that I could raise the attachment tongue correspondingly as the strips rose. This modification does not alter Moxon’s method in any important way, while making the machine easier to use.

“At the farther end of the Plank is erected a square ∫trong piece of Wood…This square piece hath a square wide Morte∫s in it on the Top…upon the top of this is a strong square flat Iron Coller…”

Fig. 5.7 Detail of cutterhead and slide board clamped into the end-Vise of a cabinetmaker’s workbench. The device is set up to make a side-to-side (flammleisten) waveform moulding (drawing by Thornton)

This is the business end of Moxon’s device which I call the “cutterhead.” My upright block was made of a single piece of maple, with the appropriate mortises as described. I added two projecting through-tenons to fasten the block into the plank, so that they could be gripped by the end-Vise of my workbench when the machine was in use, and allow me to easily disassemble the machine when it was not. The purpose of the collar is to clamp the fixed scraper-type blade perpendicular to the stock piece. My collar was forged from mild steel, as were the screws that tighten it on the block. Like Moxon, I forged perforated disks on the ends of the screws, so that a bar could be inserted to tighten them with lever action. It is important that the blade not move while in use.

Moxon is at his sketchiest when it comes to how the depth of cut is gradually increased, although the engraving seems to show what the description omits. A bar is shown penetrating the block underneath the “rack” that appears to be both tapered and furnished with a threaded rod for gradually advancing it under the work. There can be no other way to do this in a controlled way. Jutzi and Ringger in their discussion of Moxon’s machine had a different interpretation.19 They speculate that this knob, projecting out of the far side of the machine, was used manually by a helper to lift the guide rod and workpiece against the blade. Moxon however, refers to this as “a wooden screw called a Knob.” He also appears to illustrate, though he does not discuss, the taper of the polished rod that is advanced by this screw-knob. It seemed clear to me what he intended: I made a steel bar with a T-shaped cross section that would slide through T-shaped slots in the block. I put the taper side up, as Moxon appears to do, and simply accounted for this cant in the rack and “riglet,” by setting my attachment-tongue into the pulling block at the same angle.

Fig. 5.8 Making a
moulding on the Moxon “Waving Engine.”

I captured the end of my adjusting screw-rod with a sort of clutch lever that would allow me to easily disassemble the machine, an alteration necessitated by my own tight space that again, did not alter Moxon’s device in any important way. The screwrod uses a fine thread so that I can very gradually raise the work under the cutter. In use, one or two revolutions of a rosewood knob on the end of this screw increases the depth enough for the next cutting pull. The handles on my pulling block were also made of turned and polished rosewood, press-fitted onto a steel rod, which runs through the block, again for ease of knock-down.

“But before you draw the Rack through the Engine, you must consider the Office…of the iron screw…for by these screws, and the Rabbet and Groove, your work will be evenly gaged all the way…under the edge of the iron.”

Moxon shows only one screw, though he refers to them in the plural. These screws serve to keep the work “gaged” under the blade. The end of the screw shown was fitted with a flat iron disk, that appears to be a sort of wear-plate against the moving template and workpiece, called the “rack” and “riglet” respectively by Moxon. Jutzi and Ringger speculate on two screws, one from each side, that enter at an angle. Their drawings are interpretive reconstructions as they did not build such a device.

I believe that Moxon clearly shows a screw entering perpendicular to the cutter-head block. I also decided to use two screws, so that I would have greater flexibility than could be achieved with just one, though the inside surface of the cutterhead could have conceivably gauged the other side of the strips. Instead of iron, I made my screws from lemon-wood (Calycophyllum candidissimum), a beautiful close grained relative of boxwood, and equally hard-wearing. I threaded these with the Beall router attachment, and made decorative double volute-shaped flanges on the ends similar to the screw end shown by Moxon. I decided that locking washers were a good idea if I wanted to keep my work well “gaged.” I made these from rosewood also, and placed them on the outside of my block where they are easier to get at.

My blades were made from 01 steel, a high-carbon, oil-quenching tool-steel that has low warp characteristics in hardening, and can be tempered to create a tough and hard blade. The blade “whose lower end is cut into the form of the Molding you intend your work shall have…” has a single bevel facing toward the pulling block. I filed and ground the shapes before hardening the blades. I sharpened them once on the bevel, then subsequently only on the flat side.

“Then if you lay hold of the handles of the Block…and strongly draw upon them, the Rack and Riglet will both together slide through the Mouth of the wooden piece…and as the rounds of the Rack rid over the round edge of the flat iron…the Riglet will on its upper side receive the Form of the several Waves on the under side of the Rack, and also the Form, or Molding that is on the edge of the bottom of the iron, (blade) and so the Riglet will be both molded and waved.”

The final form of the mouldings is dictated by the shape of the blade, by the form of the template or combined templates, and by the attachment point of the pulling block. The number of possible designs is multiplied by the addition of any of these elements, and quickly becomes astronomical. Even with my still limited stock of blades and templates, I will probably never produce all of the possibilities.

Fig. 5.9 A selection of mouldings made on the Moxon “Waving Engine.”

Using the Machine
I have continued to explore the capabilities of this tool in the years since I first made it, and it has provided both mental and physical exercise. In action, I hold the tongue down with my finger as I push the strips through the machine for the return stroke, then I “draw strongly” on my handles. Depending on how deep the moulding is going to be, and this is dependent on the wave amplitude of the template, I will continue to make cutting strokes until the mouldings are complete. I take coarse cuts (Moxon would say “rank”) to start out with, but by the end, when the blade is bearing more-or-less continuously, the shaving needs to be thinner than paper. I can complete some moulding strips in 15 to 20 minutes, but deep mouldings in a hard wood take more time.

Any wood that is hard and relatively dense will work well for the moulding strips. Cherry is excellent, as are pear and maple. Many of the period mouldings are executed in either ebony or a fruitwood stained to look like ebony (ebonized). I have gotten by with poplar for moulding with a gentle wave. It’s best if the grain rises away from the pulling block so that the wood fibers are severed more obliquely. Earlier on, I mounted the moulding strips to the “racks” or guide bars with a few drywall screws shortened so that they did not come through the surface of my mouldings. I still had to make them relatively thick however, and they were only held firmly in a few places. Now I prefer to use the wood turner’s trick of gluing the stock piece to the template with pieces of heavy brown paper. The finished moulding is then taken off by splitting the paper interleaves, and scraping the glue and paper residue away.

Fig. 5.10 Two views of the author’s waving engine.

The “racks” are made of hard maple. I have hand-carved some of them after stepping off the intervals with a divider, by using the same gouge across the grain both bevel side up and bevel side down. I have also used a pin-indexing jig on my table saw and router table T-slide like those jigs used to cut box joints. I did this to create bars with tight waves that would have consumed a lot of time in carving. The mathematical accuracy of this method can be both an advantage and a disadvantage depending on your point of view. Historic ripple mouldings have subtle variation and character.

No sanding is required on a properly cut moulding. The blade leaves an almost polished surface in a wood like cherry. I also discovered that pushing the moulding back through the cutter-head for the return stroke burnishes the moulding against the polished bevel of the blade. Stain will greatly accentuate the wave appearance by selectively penetrating the severed wood fibers on the insides of the wave troughs.

1. Moxon, Joseph (reprinted from the 1703 edition). Mechanick Exercises or the Doctrine of Handy-Works. Scarsdale, NY, The Early American Industries Association (1979).

2. Robinson, T. “Handscraped Waves.” Fine Woodworking, 58 May/June (1986) 64.

19. Jutzi and Ringger, 46.

Join Us for LAP ‘Open Wire’ Sat. Apr. 19

Posted on by fitz
Barley, our temporary shop dog (he and his person are visiting this week).

Chris and I will be eagerly awaiting your woodworking questions this Saturday (April 19) from about 9 a.m.-5 p.m.

On Saturday morning, an “Open Wire” post will go live. If you have a question, all you have to do is type it into the comments and we’ll – eventually – answer (we fit in weekend computer time around bench time).

Readers with relevant info are also welcome to chime in. For example – we sometimes get asked things like, “Where near Flagstaff can I buy purpleheart?” We have no idea – so if you do, please do let the poor misguided* soul who wants to use purpleheart know where they can get it.

Get those questions ready. (And check out the “Open Wire” category in the meantime – there are lots of good questions and answers there already!)

The remaining Open Wire dates for 2025 are:
April 19
June 14
August 9
October 25
December 13

– Fitz

*In all fairness, purpleheart is an excellent choice for a deck and will quickly turn gray/brown, thereby making it tolerable.

‘Good Eye:’ Six-board Chest End Panels

Posted on by fitz
A simple ogee (aka cyma recta or cyma reversa) on the ends of a six-board chest.

Both Chris and I have made and taught a lot of six-board chests over the years, and typically we lay out and cut a “boot-jack,” (inverted V”), simple arc or ogee on the ends. Those are easy to lay out and all three are relatively easy to cut…and and don’t hurt our brains or the brains of students too much.

So when working on “Good Eye” the latest artisan geometry book from Jim Tolpin and George Walker, we were both rather dumbstruck with the clever way the authors reverse-engineered the layout of a fancy-looking but simple-to-cut six-board end panel – a layout I have never produced, but have now added to my mental design library. It’s not that I couldn’t have made this shape through measuring – it just wouldn’t have occurred to me to do so; I try to always teach a layout that is scalable without numbers and requires just a few tools, such as a straightedge and compass. That way, you’re teaching the process not the result.

That’s the approach of this entire book – looking at a piece of furniture and showing how the relationships between and among its proportions, and how you can use this knowledge in the real world as you design your own pieces. (Or how to better understand what makes an exiting piece “good.”)

I’ve excerpted this section of “Good Eye” for you below.

– Fitz

Next, let’s turn our attention to the end panels. In addition to the decorative pattern covering the entire surface, the end panels have a triangle cutout (Fig. 3.23). This is not just decorative; it gives the piece four feet to improve stability.

If you look closer, you’ll notice it’s not one, but two triangles, one nested inside the other. The smaller triangle provides that space to carve some relief at the bottom of the decoration. Notice also that this smaller triangle is notched with a right-angle cutout near the floor. It’s likely that the bulk of the decorative linenfold on both end panels was executed on a single board. It was then cut in half, one for each end. So we’ll lay out a mirror-image pattern on the backside of the board and then saw them out after the linenfold is complete.

Because we are making the end panels from a single board we begin with a board that’s two units wide. Instead of three units high, we double it to six units high to have enough length for both ends (Fig. 3.24).

It’s two mirror-image triangles with a pair of smaller triangles nested inside them (Fig. 3.25). The lines and circles that create this pattern look complicated at first glance (Fig. 3.26). Yet, if we walk through it step by step, you can see the logic unfold and the genius of this deceptively simple design.

Begin by drawing a pair of diagonals across the corners (Fig. 3.27). This provides our centerline for the decorative linenfold pattern as well as the apex for our large triangle cutout. It also marks the halfway spot to mark a saw line to separate the two pieces later on.

The first large decorative triangle is centered on the board. The bottom corner of the triangle is inset one-fourth the overall width of the board. We can find that one-fourth width with another pair of diagonals (Fig. 3.28).

Note that we used diagonals just like we did before when locating one-third of a rectangle. Again, these intersections locate one-fourth of our rectangle on both the vertical and the horizontal.

The larger decorative triangles are equilateral. To locate the apex, set a pair of dividers to span the width of the base of the triangle and scribe a pair of overlapping circles (Fig. 3.29).

These two circles define our two mirror-image triangles. A line that runs from the center of one circle to the other establishes the base of our triangles. The intersections, top and bottom, where our circles overlap, locate the apex of both triangles. Strike lines to connect the width of the base with the apex on both top and bottom. These two back-to-back triangles create a diamond shape.

To define the smaller triangles that are nested inside, draw a line from the corner of the board that passes through the apex of our triangle until it crosses the saw line (Fig. 3.30).

Draw three more diagonals, one from each corner to complete the two smaller triangles. Finally, the small notch at the base of the smaller triangle. It’s simply two side-by-side squares, or you could picture it as a rectangle that’s one unit high by two units wide (Fig. 3.31).

The layout for the decorative linenfold carving is similar to the front panel. The width of the tools themselves step off the repetitions across the board using the centerline as the starting point.

One final note on these geometric layouts. For the sake of clarity, we show all lines and circles in their entirety. When you see these layouts in historic books or even remnants left on old work, the actual layout lines are abbreviated. You might see only a few intersections and tick marks. If I were laying this out, being familiar with lines, it would look something like Fig. 3.32. It’s abbreviated, but still has the information needed.

Mind Upon Mind: Improve Us

Posted on by Kara Uhl
Le menuisier (colour litho) by Fraipont, Gustave (1849-1923); Private Collection; (add.info.: Le menuisier. Illustration for Le Vocabulaire des Petits by M Fournier with designs by G[ustave] Fraipont (Librairie Gedalge, c 1895).); © Look and Learn.

In a 1937 Chips from the Chisel column, which is also featured in “Honest Labour: The Charles H. Hayward Years,” Hayward wrote, “The influence of mind upon mind is extraordinary.” The idea being there’s often room for improvement. (You can read the entire column here.)

Recently, one of Chris’s chairmaking students, Lo blue, sent us another way to drill sticks for chairs.

So now we want to know: What else have you thought of, tried out and improved upon?

To that end, we’re asking any LAP readers who have built projects from our books to share your ideas for improving the design, construction or finishing of a project. We will feature some of our favorite submissions in our new series, Mind Upon Mind. Those featured will receive a $50 Lost Art Press gift card from us.

To submit:

  • Include written steps or a summary of your improvement. Write it in a style you, as a reader, would find helpful and easy to understand. But don’t fret too much. We’ll edit it to make you look good, promise.
  • Include photos to help illustrate your improvement. You don’t need special equipment to do this. Just good lighting and your phone should be OK.
  • Include your name as you’d like it to appear in print and any links you’d like to share with readers, such as your personal website or Instagram account.
  • Email your submissions to kara@lostartpress.com.

As a great example of the above, here’s Lo’s recent submission, showing a different way to drill sticks for a chair, as detailed in “The Stick Chair Book: Revised Edition.”

— Kara Gebhart Uhl

Drilling Short and Long Sticks Lo Style

Well, after drilling the sticks for my armchair at the Lost Art Press workshop with a laser, I wondered – do I really need one? What I didn’t like about using it was how long it seemed to set up the whole ordeal. For each stick you have to move the tripod and laser, line it up, then go back to the chair, line it up and drill on. Also I just don’t want to buy more “things” (I don’t have much storage space in my shared shop). So I set out to come up with another method that so far has worked without fail on two chairs. I’ve never explained a process before but I’ll give it my best shot and hopefully it makes sense.

Things You Need

  • BBQ skewer or small dowel
  • Different colored pens
  • That sticky poster-hanging stuff that’s in the random items section in the grocery store

Marking Your Skewer

The spindle decks of my chairs so far have been 2” wide, so I mark a centerline and go over an inch on both sides. The different colors really do help here. That way, when you’re aiming down, you can match up your measurements. I spaced them 1/8” apart.

Set Up Your Axis

(Maybe that’s what it’s called? I’m not really sure, but hopefully you get what I mean with the photo …)

Snap some lines so you set up your skewer just right, lining up the driver’s side stick with the passenger side stick.

Yep, just like that.

For the back sticks, you can just line up the skewer by eye so it sits right on the 2” marking.

For this one, that meant it had to be angled.

Now, put that sticky stuff on the middle of your skewer jig and get ready to drill.

It was a bit of a challenge to photograph the fine lines of the skewer, but you can just barely see two dashes on the left here. Now, line up your drill very cleanly between the two matching dashes.

Here, for instance, you can see I’m angled a wee bit too far back.

Here, I’m almost a quarter of an inch too far to the right.

Once you line up the dashes between your armbow, drill your top hole and move your skewer to the next stick position. Drill your spindle deck hole. If you’re kinda nervous (like me) you can check with an undersized dowel to see if yah buggered up your drilling …

Well, I didn’t screw it up, great, move on to the next.

And well, that’s it. Personally, moving a skewer from one hole to the next is a lot faster and less stressful than setting up a laser.

Here are all my sticks lined up, pretty darn straight …

Maybe you’re wondering … “But did it work when you put the armbow on?” Yes, I had zero resistance while gluing up, significantly less than when I used the laser.

But … as per usual, I was sure to f%$# something up in this process.

Idiot …

Oooopsy … I drilled into the leg. 🙁

I didn’t get too worked up about it. It’s wood, it can be repaired. When I was at school for luthiery, there was a repair guy who did a lecture and I’ll never forget something he said. Something like, “I don’t repair something to make it look like it never happened, when I’m done, they’ll know it was repaired but repaired well and with care.”

I just plugged a piece of cherry in my little accident.

Here is the final chair.

About the damn ugliest thing I’ve ever made. Good god, I hope to never make anything again that inspires words like “Regal!, Master, I’ve done well in the stock market now I just like to smoke cigars! Conquer!”

I hate it.

For Sale: Comb-back Stick Chair in Figured Red Elm

Posted on by Lost Art Press

This comb-back stick chair is built entirely in American red elm, with the seat, arm and comb made from figured red elm, some of the most difficult wood I have ever saddled.

The chair is raked back for lounging, reading or sitting by the fire. The chair’s features heavily shaped arms, tapered octagonal stretchers and slightly proud and burnished tenons throughout.

I’m offering it for sale via a silent auction. The highest bid includes crating and shipping the chair to your door anywhere in the lower 48 states of the U.S. With no additional fees or charges. Details on the sale are at the bottom of this entry. First, some notes about the chair.

The chair is made from red elm, which is my favorite wood for chairmaking. The wood is strong, fairly lightweight and has a difficult interlocked grain that prevents the parts from ever splitting. The chair’s sticks are shaved and left octagonal. All the tenons are cut slightly proud and burnished. All the chair’s joints are assembled with animal glue, which is reversible, and wedged with hickory wedges selected for arrow-straight grain.

The seat is tilted 6.6°, with the chair’s back tilted 28° off the seat. The seat is 16-3/4” off the floor, making it comfortable for most sitters. The chair is 38-3/4” tall overall.

The chair is finished with a soft wax finish that I make here in our workshop. It offers a low lustre and looks better the more you use the chair. The finish isn’t terribly durable, but it is easily repaired (just add more soft wax). 

Like all my chairs, I make them as best I can, but most of the work is by hand. So you will find an occasional stray tool mark or tiny imperfection. These are not left intentionally, but they are the result of hand work.

How to Buy the Chair

The chair is being sold via a silent auction. If you wish to buy the chair, send your bid via email to lapdrawing@lostartpress.com before 3 p.m. (Eastern) on Wednesday, April 24. Please use the subject line: “Elm Chair.” The opening bid is $500. In the email please include your:

  • Bid
  • U.S. shipping address
  • Daytime phone number (this is for the trucking quote only)

If you are the highest bidder, the chair will be shipped to your door. The price includes the crate and all shipping charges. Alternatively, the chair can be picked up at our storefront. (I’m sorry but the chair cannot be shipped outside the U.S.)

— Christopher Schwarz