Marquetry update

Cutting marquetry with the mini-chevalet

With the prototype working, I’ve switched gears, and have been focusing on marquetry for the past few weeks. Specifically, the KickStarter marquetry panels discussed previously. As a refresher, the design that adorns the table top is composed of wood veneer cut and assembled like a jigsaw puzzle, a technique termed “marquetry”. This differs from the “parquetry”, or geometric patterns on the aprons.

First, I had to dust off, and tune-up the mini-chevalet. Considering the number of pieces that need to be cut, it just makes sense to get this fixture running as efficiently as it can. Like all chevalets, this is a user-/shop-made affair. Much as I’d like, you just can’t order one from your local “chevy” dealer. This is its first major run, so there are bound to be some system hang-ups – literally!

  • Alignment of the holes where guide rod runs through the saw arm is critical. Saw operation becomes stiff, and binds if this isn’t the case. Not helpful especially when cutting rice-grain-sized pieces! It also helps to clean and lubricate this rod occasionally.
  • Although the wing bolts work, tightening them with pliers provides a better grip on the blade. The blade holders on the chevalets at Marc Adams (based on the design Patrick Edwards promotes) required an Allen key to operate! So, I suppose I cannot complain about this.
  • I am still not pleased with the vertical fixture that holds the packet while cutting. It seems the packet edges get hung up on the jaw arrises. It might be beneficial to round these!

Finally, I’m able to cut marquetry! Now, it’s time for me to get busy. By my count, I’ve got around 70 copies of this flower, and its counterparts to cut and assemble!

Cutting a marquetry flower using the mini-chevalet

One final note before leaving this topic. I’ve received requests to create mini-chevalets for others. While I would like to, I really need to spend my time working towards completing this project. Consider this, though; you don’t need a mini-chevalet to create marquetry. While it certainly can be used to create one-offs, the chevalet excels at being a copying machine, and this is where its strength lays. I’ll explain several methods in an upcoming post that can be used to generate more than one copy of a design per cutting. This should clarify things (hopefully). I’ll also briefly discuss techniques requiring fewer tools so you can get started.

A commentary on (hand) tools


When I began this re-creation, I already favored the use of hand tools. It has been my experience, however, that hand tools suffer a kind of discrimination in the modern world. To the at-large public they’re perceived as being slow, backward, or for the financially poor woodworker. In short, they’re second-class citizens. This is an unfortunate perception, which I hope to change.

The usual rationale you will hear about hand tool use is:
• hand tools produce less dust,
• there is less noise with hand tools, and
• hand tools are safe(r).

While these are true, for the most part, they’re not entirely truthful. My “shop” still has plenty of dust accumulation, and I do have to vacuum the floor. However, many times I can get away with simply sweeping up the shavings rather than having a dust collection hose connected to the tool. I wear ear plugs when performing some operations, especially anything involving mallet work. More often though, I listen to the birds singing outside, or carry on a conversation with passers-by. I’ve met plenty of woodworkers who reluctantly admit that they should have been more careful with their hearing earlier on in their careers…
Also for the most part, all of my tools have “flesh-sensing technology”…

Hand tools are really for production. Yes, you read that right! Most hobbyists seldom make more than one piece at a time. So, it takes longer to set up a power tool, use it, and put it away then it does a hand tool. And let’s not even mention the time (and materials) required for jig building!

Graham Blackburn once said (paraphrasing) that the point of power tools was to decrease the cost of the finished piece. Instead it cheapened the piece! In other words, power tools compromise the design. Jim Tolpin put it another way…power tools users design pieces to the capabilities of their tools. Hand tool users design first, then figure out how to build it. With hand tools, the skilled woodworker can cut any joint produced by a machine. However, the opposite is not the case!

Hand tools require skills development. Anyone can use power tools – set a fence, or guide to a measurement, and pull the trigger…
However, this mode of operating can be limiting. People are afraid of doing things free-hand since it might not come out “perfect”.

Understanding the principles upon which hand work is based gives a woodworker a better knowledge of machine operation. To paraphrase Matthew Quigley… It’s not that I don’t know how to use power tools. I just don’t have much use for them.

In the end, most woodworkers truly aspire to employ hand tools. After all, a common marketing phrase used by power tool manufacturers is that their tool will produce results just like it was hand made!

Sticking together

Woodworkers have a variety of glues at their disposal. No one is the universal panacea – each has situations in which it excels. Since I chiefly build indoor wood furniture, I usually use hide glue.

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Hide glue comes in two flavors: hot, and liquid. The terms are self-explanatory. At the risk of redundancy however, I will elucidate. In the United States, hide glue is most readily available to woodworkers in a powdered form at two strength levels. Denoted in grams, the lower the number the longer the open time. 192 gram strength hide glue is the most common. While suitable for most woodworking tasks, its speciality is in veneering and marquetry. Also available, but much less commonly encountered is 251 gram strength glue for cabinetmaking. This glue creates a stronger bond, but sets up much faster than 192.

  • Hide glue is easy to use. Other than the heating that hot hide glue requires, it is simple to prepare, and use. Liquid hide glue can be used straight from the bottle!
  • Hide glue is strong. It is more than adequate for woodworking tasks. In certain joinery situations, it even provides a slight advantage.
  • Hide glue doesn’t smell. Many people are concerned that hot hide glue will produce a strong smell, according to the stories they’ve heard. However, visitors to my studio are always surprised to learn that the glue pot has been cooking their entire visit, and they’ve been standing adjacent to it! Use a good quality hide glue. If the glue develops a strong smell, it’s an indication that it has gone bad. Wash out the pot, and make a fresh batch!
  • Hide glue has an infinite lifetime if kept dry.

While many are familiar with these points, few are aware of its benefits.

  • Hide glue is reversible! Unlike nearly every other glue, pieces bonded with hide glue can be separated with the application of heat and moisture, that is, hot water! Every other glue that I know of requires the destruction of the joint!
  • Hide glue adheres to itself. It is the only glue of which I’m aware that will bond to itself. This quality makes it ideal in situations where the joinery is stressed, and will eventually fail, for example, chairs.
  • Hide glue is transparent to finish.
  • Hide glue accommodates certain techniques, such as rubbed joints, and hammer veneering, for instance, which cannot be achieved through any other method.

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Not only does hide glue provide these advantages, but this is exactly the type of glue that would have been used on the Oeben original.

Shellac and French polishing

During my stay at the Marc Adams School, I had a chance to refresh my French polishing skills. Today, French polishing has become synonymous with a high-gloss finish. To woodworkers, however, this term is specific to a technique for the application of shellac. Shellac is a natural product derived from insects that range in Southeast Asia. It is collected, and processed to remove the sticks, leaves, and other “foreign matter”.

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Next, it’s ground into coarse particles, and separated into various colors…

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Further processing leads to it in the familiar “flake” form with which woodworkers are familiar…
This is an over-simplification of the procedure. The interested reader is referred to Vijay Velji’s article, “Shellac’s Amazing Journey” in Fine Woodworking number 215.

When I first learned French polishing, the process began with pore filling using linseed oil and pumice. Patrick Edwards, however, omitted the oil simply applying the pumice with the pad moistened with alchol. His experience has shown that once the oil has evaporated through the shellac, as the piece ages, the accumulated pumice powder shows through. The alcohol dries well before the shellac is applied, and so the excess powder can be easily removed. This technique has the added advantage of burnishing the surface to a glossy shine, almost evident in this photo…

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This result was achieved with under an hour of effort to facilitate the seminar. However, when properly executed over the course of several days, you can understand how the surface will shine. Once, and only once this treatment is complete, can the finisher begin the shellac applications. Keep in mind that French polishing is a slow process requiring patience, and persistence. It is not meant to be rushed, and usually occurs over a period of several days to weeks.

So why do woodworkers torture themselves with this process in this “modern” day? For several reasons:
• French polishing can be performed with simple, inexpensive materials – it’s just alcohol, oil, shellac, and cloth! No fancy spray guns, or figuring out which brush type to use!
• Shellac is an easily repairable medium. Many times affected pieces can be treated on site whereas other finishes necessitate having to haul the damaged piece back to the finisher’s shop. That’s an added expense!
• Finally, as I mentioned before, shellac and its solvent, alcohol, are natural products. They’ve been used for over a century with few to no ill-health effects. In fact, shellac is one of the few “finish” materials that is an FDA approved ingredient in medicines and food products! Ever wonder how the produce in your local grocery got its shine? It has been coated with shellac!

Traditional French marquetry

I am back from another productive trip to Marc Adams School of Woodworking. Thank you to everyone for making my stay pleasant, and comfortable, as usual. On this trip, I had the opportunity to make some new friends, and become reacquainted with many old ones. My only regret is that we couldn’t spend more time together. These trips are always so hectic!

As I mentioned previously, I spent a week with Patrick Edwards learning French marquetry technique. We focused on the Boulle process, also known as tarsia a incastro. In it, the various colored veneers are bound together in a packet and cut according to the design. The packet is opened, and the picture assembled by placing the veneer pieces of one species into another. Any voids between pieces are filled with a wood dust and hide glue mastic, nearly imperceptible to the casual observer. This fundamental technique offers the marquetry craftsman the ability to generate multiple copies of a design rapidly.

A marquetry triptych

A marquetry triptych

Cutting takes place using the chevalet de marqueterie, or marquetry “easel”. This uniquely French tool allows the operator to hold the veneer packet vertically at eye-level while guiding a saw along a steel rod adjusted perfectly perpendicular to it. The accuracy is such that a piece taken from the front of the packet fits within the corresponding “hole” in the veneer on the back of the packet. The manually operated saw also offers a greater degree of control than a typical powered scroll saw. Small delicate pieces can be produced which might otherwise be lost in the machine’s vibration.

Once I’ve gotten back on schedule, one of the higher priorities on my to do list will be to tune up my mini-chevalet. My experience this week gives me a better idea of how it should work!