Did the ancient Egyptians invent plywood?

February 20, 2024Leave a comment

We think of plywood as a modern invention, but is it? it is surprising to learn that the ancient Egyptians were already using plywood. In the 1933 edition of Annales du Service des Antiquités, there is a description of a coffin whose walls, and bottom were made of plywood, found at Saqqara and dating from the Old Kingdom (ca. 2700–2200 BC). There are six layers of wood, each 4mm in thickness, placed with the grain alternating in each direction [1,2], just as you would find in modern plywood. The first layer of the interior side made of vertical boards, and the outer layer of horizontal boards. The boards were anywhere from 4-30cm in width, yet none of the pieces of wood was broad enough for the height of the sides, or long enough for the length of the coffin [3].

Fig.1: *Diagram of the plywood from [2, p.164] showing the side and bottom layers of plywood joining.*

Fig.2: *Layers of wood forming the bottom of the coffin.*

In certain places on the boards there are small holes, generally paired, which pass through all layers of the plywood, intended to help bind them together. Between boards of the same layer, connection was ensured using small independent tenons engaged and dowelled in corresponding mortises made in the thickness of each board. The joints of the boards a the corners of the body were reinforced with wooden sticks. Due to the scarcity of large wood pieces, it seems the ancient Egyptian carpenters were very skilled at the technique of “patchwork” construction, joining irregular pieces of wood “by means of flat tongues or dowels, butterfly cramps, various forms of lashing and pegging, and sometimes in fine work by tongue and groove.” [3].

Pop the bubble wrap – let kids play with tools

February 17, 20241 Comment

If you grew up in the 1980s, or before, you likely remember a time when kids were allowed to take risks, I mean our whole childhood seemed to involve a risk of one sort or another. I remember being able to buy potassium permanganate (from a chemist in Australia, the equivalent of a pharmacy), and adding a second ingredient to make it spontaneously combust. We use to carry knives when camping, and learned very early the dangers of fire. Yet we played with all these things and survived. I don’t ever remember anyone getting majorly injured, and if they did, they lived with whatever scars they had… most of which we patched up with some disinfectant and a band-aid. If someone broke their arm acting stupid on a play structure, they didn’t seal off the play structure. People that grew up in the atomic era of the 1950s had it even riskier – dangerous toys like chemistry sets, physics sets with real uranium samples, and rocket kits.

A recent article on this subject talked about letting kids take risks… including “supervised play involving tools, like using an axe and hammer to build a fort”. But instead some parents continue to dump their kids in front of a screen of some sort – I mean it’s easy right? Kids use to be outside, building forts, climbing trees, and damming creeks. These days when you walk through a neighbourhood there are few if any kids outside. There are ravines close by to where I live, which in the 1970s I imagine would have been filled with kids in the summer… today they are mostly empty. Sure the difference is that anyone born before 1980 had to amuse themselves as kids. The adage “children should be seen and not heard” rang true, although I kinda believe it was more “children should be neither seen nor heard”, at least until dinner time (when they could be seen).

*Children’s play-tools from Bonumwerke Tigges & Winckel (Germany, 1935)*

Look, I’m not advocating for dangerous toys, but iPads and gaming platforms likely do more damage to young people than any of the 1950s toys ever did. What we have managed to do is raise a couple of generations of kids that have no perceived skills with tools, few ideas about building things – whether that be tools in the kitchen, in the workshop, or outdoors (Lego sets are not really that imaginative these days, they really are just follow-the-instruction type toys), and little in the way of problem solving skills. Hammers are not dangerous, if kids are taught to use them properly, and that’s the key here, learning to use them properly. Already in the 1930s it wasn’t unusual for tool companies to sell “children’s tool kits”.

*Building models from scratch or using building kits?*

But it isn’t even woodworking tools. Kids from bygone eras built models, like ships, or aircraft, and whole model railroad systems, from scratch. There were magazines dedicated to building things, like the British magazine (and store) Hobbies, and systems of building like Meccano, Minibrix, or Fischer-Technik. That is to say there were also methods of learning to build things that didn’t involve axes and chisels. Meccano Magazine for instance included articles on building things with Meccano, but also articles on engineering things, and new concepts in transportation, aircraft, building.

You had to teach yourself basic tool skills, because if you wanted a go-cart, you had to build one yourself. Maybe you got hold of some lawnmower wheels, and salvaged some lumber from the neighbourhood somewhere, but basically you had to build the thing yourself. All these skills, often self-taught boosted your problem-solving abilities, and likely had an impact on developing fine motor skills as well.

The bottom line is that we have somehow concluded that all these skills can be learned in a virtual digital realm, and that just isn’t true. Because what we end up with is people who grow up with few if any real skills, i.e. they can’t even use a hammer, all because parents (and schools) feel like everything is too dangerous. Again, I’m not advocating for kids to walk around with pocket-knives, and whittling branches in the school yard, sadly those days are gone. But what about advocating for more summer camps where kids can learn some basic tool skills? It is time to pop the bubble-wrap and let kids actually learn to play with tools and build things.

What do we know about dowel strength?

February 10, 2024Leave a comment

Dowels may be becoming in more vogue again, but what about their strength? The problem with deciding whether one fastener is better than another is that fact that it is a fairly broad thing to test. It has to do with many differing factors: the diameter, length, and species of the dowel, the type of adhesive used, and or course the characteristics of wood being joined.

Most of the explorations into dowel strength have compared them to other joints using simple tests of joint failure. A good example is this experiment from Canadian Woodworking from 2010. They tested a T joint in solid oak by comparing: (i) a 3-dowel joint (⅜”×2″), (ii) a mortise and tenon joint, and (ii) a 2-biscuit joint. The biscuit failed at 325lbs of force, the M&T at 500lb, and the dowel-joint at 650lbs. An article, “Joint Success” in British magazine Furniture & Cabinetmaking showed the following failures (tested using a hand-pump hydraulic ram) is shown in the table below. None of the fixings failed.

Method	Specs	failure (psi)	What failed?
biscuit joint	1 × No.20	180	glue line + fracture of material parallel to biscuit slot
Dowelmax	5 × 10×50mm dowels	660	glue line
Domino	2 × 8×40mm tenons	400	glue line + partial fracturing along the grain
mortise and tenon	45mm depth	420	glue line
pocket hole		280	screw and glue line

Furniture & Cabinetmaking

Yet another test from the November 2006 issue of Wood Magazine “Wood Joint Torture test”.

Method	Shear test (lbs)	Pull-apart test (lbs)
mortise and tenon	1017	2525
Dowelmax	609	1866
Beadlock	541	1486
Domino	464	1170
biscuits	187	766

Wood Magazine (2006)

The reality is that actual testing of joints would likely have to include the use of different species of wood for dowels, the use of various glues, and the application to various types of connections, and target species. It would require a large study that also assessed the effect adhesive curing has on the strength of a joint. There is actually a load of commercial research into the area of fastener strength, which isn’t really that surprising. This is partially because it is the most commonly used joint in commercial furniture construction (largely due to the fact that it is inexpensive). With the resurgence of interest in multi-storey wooden buildings, there will no doubt be more interest in the use of dowels in timber engineering. Below are some examples of dowel strength in the literature.

In a 2022 article from the Warsaw University of Life Sciences [1], the authors investigated the influence of the type of invisible wooden connectors on the strength in glued corner joints for chipboard and MDF, which are commonly used in the construction of box furniture. They used (i) four wood grooved beech dowels, (ii) two beech Domino tenons, and (iii) a mixed arrangement of connectors. Results showed that dowels provided the highest strength over Domino tenons. They also determined that the use of MDF over chipboard increased the strength.

Many studies look at withdrawal strength, which isn’t exactly the sort of strength tests you see in peoples workshops. A 2020 study [2] looks at the withdrawal strength of 8mm plain and spiral dowels made of beech and oak. The authors investigated the influence of relative humidity, dowel structure and wood species on withdrawal strength. Spiral dowels were found to have a significantly higher withdrawal strength over plain dowels. The influence of the wood species was not found to be statistically significant overall.

Another study [4] looked at the joints made from hardwood plywood of 19 mm thickness, using beech and hornbeam multi-grove dowels in various diameters (6, 8 and 10 mm) and depths of penetration (9, 13 and 17 mm). The best results were for joints made with 8mm beech dowels penetrating 17mm into the joints. The 10mm diameter dowels failed, likely due to reduced edge thickness in the panels. In general strength does increase with dowel diameter. There are even studies which look at optimal dowel spacing. In one study [5] the author found that the optimal spacing of dowels in cabinet construction (MDF and particleboard) was 96mm. Spacings of 32mm and 64mm resulted in a reduction of the maximum load-bearing capacity per dowel due to over-lapping zones of influence by neighbouring dowels.

There are even studies that look at structural joints made with axially loaded glued-in hardwood dowels [3]. The authors of one study [3] look at various large plywood (Glulam) beam configurations held together with a series of 12mm by 120mm dowels. Withdrawal strength was found to be about 30 MPa (4351 psi), and overall joints have high strength properties (except the dowel joints do succumb to brittle shear failure of adhesives or wood members).

In all likelihood, dowels are a very good choice for holding together a joint in a piece of furniture. I mean in normal furniture there is never really going to be the excess loading applied in testing. You just have to make the appropriate choice for the material being used. For most circumstances, that’s likely a ⅜” diameter spiral dowel, made of a species like beech. It may be even possible to use them to join larger structures such as workbench bases, where multiple ½” diameter dowels, 3-4 inches in length could be used.

Weird German metal handplanes

February 7, 2024Leave a comment

The Germans really were never into metal planes, although it seems that some companies did flirt with the idea, more for hobbyists than real woodworkers though. These planes came from the 1935 catalog of German tool company Bonumwerke, Tigges & Winckel K.-G.. Founded in 1860 by Robert Tigges in Dörfchen Cronenberg, it primarily produced steel stamps. In 1869 the company moved to Remscheid-Hölterfeld and production was expanded to include tools for plasterers, sculptors and gold workers. The Bonumwerke had been based in Langenberg since around 1920.

The “Amerikanischer art” metal plane was meant to mimic American metal planes. It came in three variants: the 2100 (120mm long), the 2101 (160mm) and the 2102 (210mm). This is basically a pressed metal plane with wooden blocks for handles, almost like a poor-man’s infill plane – like super cheap to make for those who wanted to “experience” the American plane. The second plane was made for hobbyists, and also came in three variants: No.805 (100mm without nose), No.806 (100mm), and No.807 (140mm). This is essentially a type of block plane, but made entirely of pressed steel. It almost has the feeling of a modern RALI.

Miniature or tiny planes?

January 31, 20245 Comments

Since the early days of metal planes there were quite a few designs based on the idea of “miniature” planes, although in truth they were not true miniature planes, but rather just tiny planes. Some manufacturers even used the term “toy” plane. Miniature assumes some level of similarity to a normal size plane, i.e. it applies to an exactly proportioned reproduction on a very small scale. In all likelihood these planes evolved because the likes of cabinetmakers and joiners wanted a small plane to do small jobs like planing trim in hard to reach areas. One example would be to make small adjustments to room trim, or other architectural features.

They appeared in the late 1800s at the same time as the move towards the use of metal planes. It possible that the concept of a small plane evolved from violin (luthier) makers planes (also known as the model makers planes) which have been around since the 16th century. There are limits to the size of small planes which can be crafted in wood, and in all likelihood they evolved because of a need and advances in technology.

One of the earliest tiny planes was likely the Stanley No.101 which appeared in 1877. This was followed by Stanley’s No.101½ bullnose in 1880 (which didn’t actually appear in any catalogs). It was not until 1936 that Stanley introduced the No.100½ curved bottom. The No.101 and No. 100½ were produced until 1962, however the No. 101½ was discontinued in 1929. Stanley also offered a No.201 which was just a nickel plated version of the 101, from 1890 to 1910. At the same time, Bailey’s “Victor Plane Company” introduced a line of five tiny planes – the No.50, No.50½, No.51, No.51½, and No.52. They were produced for a short period from 1880-1884, and all had cast iron bodies but differing finishes and adjustment mechanisms.

Most of the tiny planes that came after those of Stanley took on the structure of the No.104 – 3½” in length with a 1” wide blade. Sargent also produced a tiny block plane, the No.104. manufactured from 1887-1944. Millers Falls sold tiny planes for a number of years, including the No.33 “non-adjustable block plane”, manufactured from 1929-1974. It was designed for model and instrument makers.

What about modern miniature planes? The there are a few that fit the bill. Veritas makes the tiny Pocket Plane, and Lie Nielsen make three miniatures: the Violin Maker’s Plane, the Model Maker’s Block Plane, and the Convex Sole Block Plane.

Is there a future for dowels in furniture making?

January 26, 20241 Comment

Let’s talk about dowels. For years they have been the lesser cousins when it comes to joinery for furniture. They are often as maligned as butt-joints, but is the “dislike” warranted?

There are of course many ways to join two pieces of wood. For joining corners the most popular method is often dovetails – for aesthetics alone. Are dovetails always practical? You can make them by hand, or use a jig and router to speed things up, but they aren’t the be-all-and-end-all. Hidden joints are done in many ways – some people like using the tenons of Festool’s Domino system (the system is nice, bit pricey for the home user), others sliding dovetails (nice looking, but a lot of work for being mostly hidden), and still others use dowels.

Plain old dowels. The word dowel is an old English word analogous to “doule” which simply means a part of a wheel. It can also be traced its history in the Middle German language “dovel” which meant to plug. Now dowels have been around for quite a while. Viking longboats used trunnels (tree-nails or big dowels) to hold ribs together, and dowels were used to pin structural members joints together in buildings. However the use of dowels in furniture construction came as a late development, appearing in the early 19th century as an alternative to mortise-and-tenon joints.

For many years many woodworkers have shied away from them. This may be in part because of poor experiences with dowels in a certain self-assembly flat-packed furniture. But dowels are actually ideally suited to building with plywood, especially Baltic-birch. The multi-layered form of plywood is not well suited to the likes of dovetails, or mortise and tenon joints. It is also an ideal way of joining solid wood.

It also may be because the old-type dowel-jigs have always been somewhat mediocre. They weren’t really designed for placing dowels along the edges of large cabinet carcasses, or on mitre joints. The early ones, like the Stanley No.59 were versatile in application, but suffered from only being able to drill one hole at a time. The newer ones include the Veritas Dowelling Jig, which is good at some tasks, but not the most optimal solution , and the Woodpeckers Ultimate Dowelling Jig 2.0, one of their OneTIMETools… too short lived to form any sort of opinion on. But then there are what some consider the game-changers, the DOWELMAX and JessEm jigs. These tools let you put dowels in just about any configuration (each has its own pros and cons).

Then there is the dowel pins – spiral-grooved or multi-groove. The grooves, or flutes allow air to escape and glue to fill the voids as the dowels are inserted. Without them, it is possible that the dowels would not be able to be inserted completely into the hole. There is no real definitive answer as to which has the better holding power, but both are infinitely better than smooth dowels (unless the dowels are to be used in through-dowel situations where they are exposed). The dowels are generally like pressed-beech biscuits, with the compressed wood in a ⅜” dowel expanding about 1/32″ (0.8mm) on contact with moisture in the glue, creating a tight fit.

Dowels offer a convenient, inexpensive way to make a robust joint. They can give incredible strength to mitre-joints, and make carcass joinery quite efficient. Whether you choose to use them is really up to you, but they offer a method of joinery that is both inexpensive and sturdy. But how strong are they really? Well we will tackle the concept of dowel strength in the next post.

Driving through redwoods?

January 22, 2024January 22, 20242 Comments

Who ever thought that putting holes through super large trees so that cars could drive through was a good idea? A number of big trees in California had tunnels dug through them in the late 1800s and early 1900s. One of the most famous was cut in 1881 through Yosemite’s famous Wawona Tree. It was cut as a tourist attraction, and was the second standing sequoia to be tunnelled – the first, a dead tree, still stands in the Tuolumne Grove in Yosemite). The Wawona Tree stood for 88 summers before falling during the winter of 1968-69 (it was 2,100 years old).

There are currently three different tree drive-through : the Shrine Tree (4,500 years/hollowed by fire), a coast redwood, the Chandelier Tree (2,400 years old/opening cut late 1930s), and the Klamath Tree (785 years old/opening cut 1976).

Cutting holes through such majestic trees really seems like a very odd thing to do.

The conundrum of storing handplanes

January 16, 20243 Comments

Check any woodworking forum and you will always a brisk discussion over whether a plane should be stored vertically on its sole, or horizontally on its side, and whether one is better than the other. Proponents of each will find some hole to pick in the oppositions approach. Then there is atop the bench – how do you rest a plane not being used for a short period? It is somewhat of a conundrum… or is it?

Let’s deal with the bench-top first. One side of the argument will say that by resting a plane on its side, it won’t result in any damage to the plane (blade). That’s certainly a valid argument, if the bench top were made of anything but wood, or contained pop-up metal bench dogs or the like. But because benches are usually made of wood, leaving a plane upright will have little or no effect on the sharpness of the blade. The first thing anyone normally does when setting down a plane is to check that the space is free of things that could cause harm. In fact it is easier to handle if it is left up-right, and the blade is not left exposed as it is if the plane is on its side. Exposed blades are more likely to be accidentally nudged by some other (metal) tool, or by a human body part. If you are concerned, it’s easy to use a piece of anti-corrosion liner somewhere on the bench to place the planes atop (it also has grip-like texture), or even use a strip of wood ¼” tall to sit the toe of the plane on, thereby raising the edge of the blade off the bench. Placing a plane on its side on the workbench isn’t something I would necessarily choose to do.

*Sit the plane on a piece of shelf-lining*.

What about storage? Well in this respect I don’t see that there is much difference. Many people store planes in the upright position on the sole, either vertically, or on an incline (in a till) – it really depends on personal preference, often related to storage options. For example if you store your tools in a chest, then arguably the planes have to be stored vertically due to space constraints. Inclined plane storage options do take up more room, but they make bench planes readily accessible. Storing planes vertically in a wall cabinet is okay, but may prove to be an accessibility challenge for bench planes. Some people even build cubbies, where only the rear of the tote is showing (this makes them easy to grab, but does result in a deeper cabinet).

Neither storage method adversely affects the sharpness of the blade in any manner (unless you are slamming into its storage cubby!). Vertical storage sits the blade on wood, and horizontal storage typically sits the plane with the sole nearest the cabinet, so nowhere near anything it could cut, i.e. the woodworker. If you’re worried about the metal-wood interaction, the base could also be lined with cork or Crubber.

At the end, the storage method is your choice, depending on your own needs.

The jolly Christmas block plane

January 2, 20242 Comments

The Germans don’t make a lot of metal planes, I mean they never really did. They still have quite a vibrant wooden plane manufacturing scene. But there is one company that makes metal planes in Germany, and that company is KUNZ Tools. Kunz was established by Gustav Kunz in Fürstenwalde in 1910. After WW2 they moved to Hanover then in 1992 Tresselt-Schlüter GmbH in Grossbreitebach/Thuringia took over production of the planes. They are easy to identify because they generally have have the upper body of the plane epoxy-coated in a vibrant green, with the lever cap in red – very much Christmas themed. They manufacture everything from bench planes to pocket/specialty planes, and even have a KUNZ-plus range of planes manufactured stress using relief annealed grey- cast iron (as opposed to ductile iron).

One plane I find interesting is KUNZ’s interpretation of the No.9½ block plane. The colour-scheme aside, there isn’t really a lot that sets it apart from any other plane. A review from Fine Woodworking in 2012 says this about the plane: “Poor machining made the tool uncomfortable to hold; blade adjustments were coarse and didn’t hold; insufficient bed support for the blade; sole was flat.“. There is just something lacking in this plane. Just looking at the plane you can see the finger-holds have a weird and unnatural shape. Why are some knobs bronze (coated?) and others steel? Will that lever in the back dig into your hand?

I hate to say it, but this is a case of German-made, but why? It doesn’t seem to live up to the aesthetic design or precision that tools Germany are known for, almost stuck in time in some respects. I’m sure from a materials perspective the planes are good quality. The planes are available worldwide, and seem to sell for C$130/US$100, which isn’t exactly inexpensive when compared to other block planes. It’s a pity because KUNZ does make some interesting tools like spokeshaves, including one with an adjustable mouth.

Is a cheaper plane worth it?

December 29, 2023

Following on from the previous post, I thought it would be interesting to look at differing costs between more premium planes and lower-end planes. In the table below I have included a range of low-angle block planes from varying manufacturers. Differentiating planes is achieved by means of price, and construction characteristics. Most planes have a body made of ductile iron, but it is hard to tell the quality of the casts without performing some sort of destructive testing. The adjustment mechanisms range in quality depending on materials, and machining. Finally, lower priced planes tend to have more generic, high-carbon type blades.

There are three price tiers in the table below: high, medium, and low. On the upper tier are HE and LN planes which cost more in part because they contain a good amount of bronze. The HE is a block plane for those who like pure bronze tools. Both planes are made in countries with higher wages, and likely better quality raw materials. With companies like LN, materials and workmanship are also guaranteed for the life of the tool. Veritas (Lee Valley) also produces exceptional quality planes at a marginally lower cost (possibly to do with larger economies of scale), having it sit in the mid-tier price-wise. What is evident is that there is little price difference between the likes of Wood River (WR) and Veritas planes – in fact the Veritas plane is only US$13 more. For that US$13 you are getting a Canadian made plane with bronze adjustment mechanisms, a better quality blade, a better casting, and more ergonomic finger grips. The WR plane is basically an amalgam of the Stanley No.65 low angle and No.18 standard angle knuckle-lever cap designs (the knuckle-lever isn’t really the most effective mechanism around), with little in the way of innovation.

	Cost (US$)	Body	Parts, e.g. cap lever	Blade	Weight	Manufactured
Henry Eckert (HE) No.60½	$243	bronze	bronze	PM-10V	1250g	Australia
Lie Nielsen (LN) No.60½	$187	ductile iron	bronze	A2	680g	USA
Veritas (LV) LA	$143	ductile iron	iron, bronze	A2	790g	Canada
Wood River (WR) LA	$130	ductile iron	chrome-plated steel	high carbon	925g	China
Melbourne Tool Co. (MT) LA	$95	ductile iron?	brass	M2 HSS	750g	China
Stanley Sweetheart (S) No.60½	$80	ductile iron	brass	A2	1150g	Mexico

A comparison of prices and characteristics of low-angle (LA) block planes

If you want a classic Stanley-style plane then buy a vintage one. A vintage Stanley No.18 goes anywhere from US$70-100, and a No.65 around $US100-130. Sure it may need some TLC, and the chrome may not be shiny, but it is a quality tool that has stood the test of time. At the low-end of the scale are Melbourne Tool, and Stanley. I actually think the Melbourne Tool Company plane is much better positioned from a price perspective than the WR. It is a nicer looking plane as well, although I don’t know if there are any true design innovations here. Comparing it to the Stanley, it’s price-point may be a higher than it should be, but Stanley has the advantage of larger production runs and lower manufacturing costs (manufacturing labour costs are 19% higher in China compared to Mexico, and shipping is cheaper as well).

Now some people don’t want to pay more for a premium plane, and that’s fair enough. Higher costs may be indicative of a more small-scaled production, quality materials, and a high-quality manufacturing process. Lower cost is sometimes an indicator that the quality of the materials may not of the same standard, or production costs, i.e. wages, are lower (although by many estimates costs aren’t that much lower than manufacturing in the USA). Ultimately though when you take all these factors into account, the difference between the lower and higher ends of the spectrum does rest in where they are manufactured. Remember, sometimes it’s important to support local companies that are making a genuine product.

P.S. From what I have read, if you are looking for a bargain block plane, then the Stanley may actually be the best option. However they are almost impossible to source in Canada, but you can find them at Home Depot in the US.

P.P.S. If you are buying a Wood River block plane in Canada, they sell for C$216, whereas the Veritas low-angle sells for C$195 – you do the math.

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