A blue Albanese bear watches over the murder of his bag-mates.
One thing I love when Megan Fitzpatrick teaches in our storefront is that I am exiled from the bench room, and I need to amuse myself without woodworking tools or loud music.
So today I decided to experiment more with making gelatin-based glues. In December, I successfully made glue using gummy worms and bears. Then I made some nice liquid hide glue using unflavored gelatin.
I want to develop some recipes that readers can follow and replicate. So today was all about careful measurements, calculations and carrying the gazinta.
The gummy bears right before they are covered in water and melted.
Gummy Glue 2
When I made my first few batches, I threw some gummies in the glue pot and added water until the stuff looked like glue. That’s still a valid approach. But I wanted to see if I could create a recipe that was a little better thought out.
Gummy bears are basically gelatin and sugar, with some added colors, flavors and a little carnauba wax to keep them from sticking to each other in the package. Today I’m using a local brand of gummy, Albanese, which is made in Indiana. They are softer than your typical Haribo bear and smell a good deal more.
According to the packaging, the bears are about 44 percent sugar. That makes them about 56 percent other stuff – mostly gelatin. So a rough guess is that 100 grams of bears contain about 50 to 55 grams of gelatin. For simplicity, I’m saying that the bears are 50 percent gelatin.
So a typical hide glue recipe combines 75 grams of hide glue pearls and 3/4 cups (177ml) of water. So, I’m melting 150 grams of bears in 3/4 cups of water. (Useful fact, the Albanese bears are 5g each, so you can count out 30 bears instead of purchasing a drug-dealer scale that weighs in grams.)
I know some of you are concerned about the sugar (won’t bugs eat it?). I have been reading some academic papers that suggest that the sugar might actually make the glue stronger. But we will see.
The gummy glue is cooking now, and I hope to convince Megan’s students to use it on their sawbenches (or at least have a taste of it).
My first batch of gelatin glue (left). The second batch in progress (right). You can see some dry powdered gelatin at the bottom of the jar.
Death Grip Glue 2
When I made my first batch of gelatin glue, I measured out the gelatin using volume because the original recipe used volume. When I poured the water into the gelatin, the gelatin immediately soaked up all the water and left about 25 percent of the gelatin powder bone-dry. So I added more water (I don’t know how much).
When I cooked the glue, it came out watery. Too watery. It would run off joints like water. So I cooked it down until it was snot-like. Then it worked great.
My goal with this second batch of glue is to create a more reliable recipe. First I converted the hide glue recipe from volume to weight. Why? The gelatin is like fine sand. The hide glue pearls are like fine gravel. So there’s some air between the pearls.
When I weighed one cup of glue pearls, they equaled 150 grams. So I put 150 grams of gelatin in a clean glass jar and added 1-1/2 cups (355ml) of water.
Again, the gelatin soaked up all the water, leaving some dry stuff at the bottom. I decided to just leave it for now and see what it looks like tomorrow when I need to cook it.
One of our two portable “Vortex Cone” Jet collectors. These are due for a good cleaning on the first nice spring day. That means taking them apart and sucking out the filter folds with a smaller vacuum. Not my favorite job.
From time to time, we get asked about our “professional setup” for dust collection. It’s not what you might expect from a (semi) professional shop…or maybe it is exactly what you expect, given that we’re known for hand-tool stuff.
But we do use machinery – particularly for stock prep and rough cuts. Plus, there’s a fair amount of sanding in making stick chairs. Our machine shop (aka “The Electric Horse Garage“) is, however, quite small; there’s no room for 6”-diameter piping or a large cyclone. Instead, we have two Jet Vortex dust collectors for the large machinery. One is hooked up to the jointer and planer, with manual gates that we open/close to direct the suction to the machine in use. The other is for the table saw. I don’t know about Chris, but before I turn on any of these three machines, I first poke the bag to make sure the dust level isn’t too high. Trying to birth an overfull garbage bag full of fine dust between the uprights is a bear, especially on the table saw (that dust is heavy!).
An off-the-shelf solution (we had no room for another large portable unit).
For the spindle and belt/circular sander, we have a small Ridgid unit hanging on the wall (which reminds me – I’d best check it given last week’s chair class; the collection bag doesn’t hold much).
We are very bad about checking the collection bag in this one. My one New Year’s resolution is to never again have to pry out impacted dust and shavings. At least not in front of anyone next time.
On handheld machines such as the random orbit sanders and the Domino Joiner, we hook up Festool dust collectors (I bring mine in from home during classes so that we can set up two stations). Key is the addition of a 98-cent hose clamp to keep the collar from slipping off the machine’s dust port. (You can just see it in the image above.)
In the bench room, the only stationary(ish) machines we have are two bands saws. One, Chris’s venerable Delta/Rockwell, predates dust collection ports, but on the new Jet band saw we hook up the shop vacuum if we’re making anything more than a short, quick cut. Might as well go through the teensy bit of trouble of hauling out the vacuum, given that we use that same vacuum to clean up the machine and floor after using the band saw. Every time.
For larger stuff, let it never be said you can’t find a broom around here. We have plenty – all from Berea College in central Kentucky.
– Fitz
P.S. This is Chris, chiming in. This year we are going to add an electrostatic air scrubber to our machine room. We are serious about keeping the dust down. Also, the only sanding on the stick chairs is on the saddle. I sand about 5 minutes per chair. Beginners have to sand more. So it can seem like a lot when six beginners build chairs.
Typically when we announce an open house I get three or four complaints along the lines of “why didn’t you let us know sooner.” So for those three or four people:
The 2023 Summer Open House at the Lost Art Press storefront is on July 29. We’ll open the doors at 10 a.m. and lock them behind you at 5 p.m. We will probably have a special gift, guest demonstrations, etc. But I don’t know anything more than the date at this point. (And we will of course let you know more when we figure it out.)
An assortment of JP chairs built between 1880 and 1900.
If you’re a vernacular furniture fanatic, or you live in Tasmania, you may already know what a Jimmy Possum chair is. If you’re one of the other 7.4 billion people on earth, buckle up and read on about my journey to Jimmy Possum: an unbroken tradition.
A mob of wallabies on the roadside near the chairmaking class.
With international borders reopened, wanderlust took my wife, Kathy, and me to the farthest reaches of Earth (for us): Tasmania. We landed in Hobart on a dark, rainy December night. After picking up our diesel 4-wheel-drive rental, we set off into the rural part of the main island. Using all my skill and every last ounce milliliter of focus, I narrowly avoided the mobs of wallabies zig-zagging through the country roads.
Chairmaking class started the next morning when Stanley, the shop dog, dragged us out of bed. Jon Grant teaches a number of American Windsor chair classes in Melbourne, but if you ever get the chance, building a chair with him at his home studio in Tassie is a one-of-a-kind experience in one of the most uniquely beautiful places on earth. Being half a world away from the States, Jon and I agreed that it would make more sense for us to build a Tasmanian chair.
Left to right in Jon’s studio: My Peddle chair, me and an original Peddle chair built circa 1900.
The George Peddle chair came to prominence around the same time as the Jimmy Possum (“JP”) chair, but in a different part of Tasmania and for a different purpose. If you looked at the photo above and thought “Hey! That’s not a stick chair,” hold your (shave)horses, we’re almost to that part.
I learned a number of things in Jon’s studio, including (but not limited to):
1. How to turn wood 2. Tasmanian blackwood is beautiful 3. Wallaby patties are delicious 4. There’s an ongoing JP chair exhibit in Launceston.
If someone asked me what a JP chair looks like, I’d say it looks almost like the love child of an Adirondack lounge chair and an Irish stick chair. If someone asked me how to pronounce Launceston, I’d probably just embarrass myself.
If you do an internet search for “Jimmy Possum,” you’ll readily find the legend of the man himself. For the purposes of this post, it’s sufficient to know that:
1. He was not a possum or a professionally trained chairmaker 2. The JP chairmaking tradition is alive and well. In the 35 minutes I had at the exhibit before speeding to the airport, here’s what I saw.
The Legs The defining characteristic of the JP chair is the fancy leg design. The four legs suspend the seat, pass through it, and support the arms to boot. The lack of stretchers, combined with the rake, creates a lot of negative space under the chair, highlighting the smooth, shapely legs. If you’re planning to build one yourself, make sure that leg grain is straight!
Pinned and wedged JP chair built from blue gum circa 1895
The Joinery It’s not obvious at first glance, but this chair has more pins than granny’s sewing kit. Legs meet seat? Pins. Legs meet arms? Pins. Sticks meet seat? Pins. Sticks meet crest? Pins. You get the idea.
Many of the arms and crests are secured with a “belt and suspenders” approach, having both pins and wedges, but the curiosities don’t end there. A number of JP chairs sport through-tenons with just pins, no wedges. The early JP chairmakers lived in or around small farming settlements, so I suspect the chairs were built using techniques the makers knew from their trades.
We all make mistakes! Six legs, doubled arms, and a warped seat. Built circa 1890.
The Seat Many of the seats are a single board, and a lot of them appear to be rived. These days, people rarely build chairs using green wood seats, and you can see why in the photo above. On the other hand, most of these 100-year-old leg-to-seat joints are fantastically tight from the green seat drying and shrinking around the leg.
A massive JP chair displayed next to a JP highchair, both built circa 1895.
Know Your Neighbor It may be difficult to tell from the photos, but the chairs range drastically in size. To me, this suggests that most of these chairs were made for friends, family, the maker themselves, or by commission, rather than as spec chairs. This isn’t surprising, given that the town of Deloraine (where JP chairs are believed to have originated) had a population of 836 as of the 1881 census.
All Rake, No Splay If you hate resultant angles (sorry Chris), this is the chair for you! The nature of the floor-to-arm legs prevents the chair from having any splay. If you’re having trouble visualizing it, draw a JP chair with splayed legs, then try to figure out where you’d sit.
A selection of chairs built circa 1900.
The Similarities Despite being on the other side of the world, parts of these chairs have some similarities to historical vernacular chairs from the northern hemisphere:
• The front edge of many seats is natural, not cut, creating a bevel. • The seats are not saddled. • The arms intersect the outermost back sticks, similar to an Irish stick chair. • They were made from local timber, then (in many cases) painted green.
All coincidence? Unlikely. In 1870, just more than 40 percent of the population of Tasmania was made up of immigrants. Some were gold miners from China and mainland Australia, but the majority were from the U.K. (which at the time included all of Ireland).
I find the JP chairs beautiful, but also meaningful. They began popping up around 1870 (or perhaps a little earlier), only a few decades after colonists settled in Tasmania. Most of the early years were likely spent fighting the native Palawa people, figuring out how to eat the local plants, farming in unfamiliar soil and generally struggling to find a way of life. The early Europeans sent to Tasmania were primarily convicts, but not the murder-y kind. They were guilty of “petty crimes” like stealing bread, committing fraud or sharing political opinions. I like to think of JP chairs as a sign of life improving for the settlers – early evidence of leisure activities.
The JP chair is a form of folk art and has a healthy bit of tradition associated with it. I’ve never spoken directly with any of the families who have been making JP chairs continuously for more than 100 years, but I suspect they’d tell you not to touch a lathe. Historically, a drawknife is used to shape the Tasmanian Blackwood legs and spindles.
There’s a lot to learn from building a traditional form the “right” way, but I also have a habit of doing things my own way, so I’ve decided to build two chairs. I don’t have access to green wood, so I’ll start by setting aside a large chunk of kiln-dried ash to Galbertize*. While that’s marinating, I’ll get to work making an “Amurican” version from walnut using handplanes and a scorp. Maybe I’ll even add stretchers, like the Obnoxious Yank that I am.
Tree ferns surrounding Tasmania’s Russell Falls.
If you have the chance, go check out the JP exhibit before it ends in May. If you can’t get there in time, renew that passport and go to Tasmania anyway. You’ll see, among other things, some incredibly humbling trees.
– Lewis Laskin
* Galbertization: Pete Galbert lays out a method for rehydrating kiln-dried wood to be worked with a drawknife in his “Chairmaker’s Notebook.”
Bonus Content: Before today, this next piece of knowledge was only available to those who live in or road trip through Australia. The local market price of a Bag O’ Poo ranges from $2 to $4 USD, depending on provenance (sheep, horse, or cow), size of the bag, and currency exchange rate.
Fig 4.1 Learn to chop mortises accurately and efficiently and you’ll be able to build most anything. Joint stools will give you lots of practice – there are 16 joints in each one.
The following is excerpted from Chapter 4 of “Make a Joint Stool from a Tree,” by Jennie Alexander and Peter Follansbee.
Joint stools are a fascinating piece of British and early American furniture. Made from riven – not sawn – oak, their legs are typically turned and angled. The aprons and stretchers are joined to the legs using drawbored mortise-and-tenon joints, no glue. And the seat is pegged to the frame below. Because of these characteristics, the stools are an excellent introduction to the following skills.
• Selecting the right tools: Many of the tools of the 17th century are similar to modern hand tools – you just need fewer of them. “Make a Joint Stool from a Tree” introduces you to the very basic kit you need to begin.
• Processing green oak: Split an oak using simple tools, rive the bolts into usable stock and dry it to a workable moisture content.
• Joinery and mouldings: Learn to cut mortises and tenons by hand, including the tricks to ensure a tight fit at the shoulder of the joint. Make mouldings using shop-made scratch stocks – no moulding planes required.
• Turning: Though some joint stools were decorated with simple chamfers and chisel-cut details, many were turned. Learn the handful of tools and moves you need to turn period-appropriate details.
• Drawboring: Joint stools are surprisingly durable articles of furniture. Why? The drawbored mortise-and-tenon joint. This mechanical joint is rarely used in contemporary furniture. Alexander and Follansbee lift the veil on this technique and demonstrate the steps to ensure your joint stool will last 400 years or so.
• Finishing: Many joint stools were finished originally with paint. You can make your own using pigments and linseed oil. The right finish adds a translucent glow that no gallon of latex can ever provide.
Now we can return to the framing parts, starting with the stiles. The first step is to lay out the mortises. We’ll outline these steps one at a time because it can get confusing. We will call the mortises for the front and rear rails “straight” mortises, those for the canted ends of the stool we will call “angled” mortises.
Stack the four stiles together, with their beveled inside corners touching, and with radial faces up.
These radial faces become the “front” and “back” faces of the stool. Take one stile, and work on its radial face.
Fig. 4.2 This story stick is another example of something for which we lack period evidence; but its effectiveness can’t be beat. In addition to serving as the principal layout reference, it functions as a wooden notebook. If you make a number of different stool patterns, mark them with the date.
To lay out the stiles’ square blocks and the straight mortises, it’s easier to use what a carpenter now calls a “story stick” that is marked with the stiles’ details, rather than working from paper drawings or patterns. This shop-made stick records the markings that are then transferred to the stile. We have made these sticks to record different stools. The locations and heights of the squared blocks, turning details and positions of mortises can all be taken from the stick to the stile. It is best to mark ONE stile from the stick, then the other three stiles from that first stile.
Make sure the foot of the stile is trimmed square. Line up the foot of the story stick and the feet of the stile. With an awl, mark the limits of the square blocks and scribe these marks across all four faces of the stile, with one exception – the top of the stile is marked only on the radial face and the corresponding inside tangential face (where the straight apron mortise is located).
Now line the stick up on the inside face and mark the locations of the mortises on this tangential face.
Fig. 4.3 Prick the points with the awl, then scribe them with the square and awl. Sharpen the awl with a file from time to time. Careful, it can draw blood when it’s sharp.
One thing to keep in mind is that the top of the apron mortise is not at the same height as the top of the stile. This mortise drops down about 3/4″ from the stile’s top end. Eyeball the top of the apron mortise and scribe it with the awl and square.
The next step is to mark the mortises with the mortise gauge. To set the gauge, make a mark with your chisel’s edge perpendicular to, but right against the stile’s arris. Next, move over one chisel width and bear down hard enough to make a mark in the wood. Then set the pins of your mortise gauge according to the location of this second chisel mark. The result is a mortise that is set in from the face of the stock the thickness of the chisel. Our mortises are usually 5/16″, set in from the face 5/16″. This spacing is based on studies of period work; 5/16″ is almost a standard from what we have seen.
Fig. 4.4 (left) This is a technique that if we heard it somewhere, we have forgotten where. It works very well. No ruler, no fiddling with the gauge up against the chisel’s sharp edge. Mark the timber with the chisel, then put the chisel down. Very safe and simple. Fig. 4.5 (right) Now move the chisel over one chisel-width. And lean on it. Now your setting is marked on the timber, and you just need to set the mortise gauge according to the chisel marks.
Fig. 4.6 Using both hands on a marking or mortise gauge might seem like overkill, but the oak is very fibrous, and when it’s green it can catch the gauge’s pins. The result can be irregular and it’s hard to re-mark a line once it goes astray. Extend the marking lines beyond the top and bottom of the mortise; this way you can check the spacing of the joint if you find you need to reset your gauge – if, for instance, it falls on the floor.
The Angled Mortises To find the location for the angled side mortises, use an adjustable bevel set to the desired flare angle. A slope of 1:6 is what we have used on several stools. Our studies of 17th-century stools show flare angles right around that figure, some less, none more. To set the bevel, set a straightedge on a framing square, positioning it at 1″ on one leg, and 6″ on the other. Then adjust the bevel to this angle and lock its nut to secure the setting. You can then scribe this angle on a piece of wood, or even scribe it on the wall. Like the adjustable gauges, the bevel can lose its setting if bumped. Having the angle scribed somewhere makes it easy to reset it. Alexander turned an adjustable bevel into a fixed one by threading a bolt through its stock and blade.
To lay out the side mortises, you must carry the line that designates the top of the stool from the front radial face across the side tangential face. Set the bevel with its handle on the front face of the stile. Line it up with the marked top of the stool, with its angled blade pointing upwards on the other outside face of that stile. Scribe this line with the awl.
Fig. 4.7 (left) Here is an adjustable bevel, and the modified one Alexander turned into a fixed bevel. If you are using one flare angle regularly, this is the way to go. It’s easy enough to come up with an extra adjustable bevel. Fig. 4.8 (right) Marking this angle is the same as any layout; a couple light passes will carefully scribe a line on the stile. We have often joked that this step requires two consecutive thoughts. It might be three.
Then use a square to carry this line across the other inside face. So the sequence is square, bevel, square. Remember that it’s best to carry the lines across the outside faces; the inside faces are unreliable. This layout is both simple and complicated at the same time. Sometimes it helps to stand the stile up and tilt it as it will be in the finished stool. Then you can easily visualize where the angled mortises are and how they rise up higher than the straight mortises.
You can repeat this process for the top edge of the stretchers’ mortises. Or you can mark this from the story stick, this time lining up the top of the stool with the scribed line that designates the top of the side apron.
Now mark the mortises’ height and width on these faces of the stile. After you mark out two stiles, lay them side by side and check that they agree. A front or rear pair should have their radial faces matching, with the straight mortises aiming at each other, and the side, angled mortises rising up toward the top of the stool.
Mortising Once you have struck the layout of the mortises, secure the stile on the benchtop near its edge. Shove one end of the stile against the bench hook then secure the stile with the holdfast.
Fig. 4.9 (left) This is the first pair of blows with the mortise chisel. Note the chisel’s bevel is just about plumb. Fig. 4.10 (right) Here, the stile is held in place by a holdfast, with a scrap of pine between the holdfast’s “pad” and the stile. This prevents bruising the stock.
Begin mortising by holding the mortise chisel with the handle tilted away from you, leaving its bevel just about plumb. Position the first cuts with the mortise chisel about in the center of the mortise’s length. A blow from the wooden mallet drives the chisel downward. Turn the chisel around, and make another chop aimed at the first. The result is a V-shaped opening at the middle of the mortise’s length. Alternate the chisel’s position in this way, enlarging the V-shaped cut; the goal is to reach the depth at the center of the mortise as quickly as possible. Then the rest of the work is just cutting down the end grain to lengthen the mortise. As you get to the ends of the mortise, bring the chisel upright so that its back surface is perpendicular to the stile’s surface.
Fig. 4.11 (left) Coming at the mortise first this way, then that way requires some shift in posture. Experiment with different methods to see what feels best. The idea is to get the mortise chopped quickly and easily. Fig. 4.12 (right) The amount of work that is split between hand pressure and mallet-driven will vary. Moisture content plays a role in this; drier stock is less forgiving with hand pressure. But either way, oak will convince you to use your whole body.
There are a few stances and postures we use that increase the efficiency in mortising. For most of the work the chisel is driven with a mallet, but sometimes hand pressure is useful as well. When using hand pressure, it helps if you rise onto the balls of your feet and come down with your whole body to drive the chisel. Lean on the top of the chisel handle with the front of your shoulder to help drive the tool into the wood. Then you can pry the waste up from the bottom of the mortise. In fig. 4.12, the left hand is used to position the chisel, and the right hand and upper body are driving the tool into the wood.
It is critical to keep the mortise chisel parallel to the face of the stile. You can sight against a square positioned on the benchtop. Drive the chisel into the mortise, then step back and sight it against the blade of the square. With practice you will learn to sight this against the face of the stile, and not need the square.
Fig. 4.13 A nice stout mortise chisel is essential when prying the material out of the mortise.
The moisture content of the oak is important at this stage; usually it’s fairly wet inside when you chop these joints. The stock in the photos was planed wet from the log less than a month before cutting these joints. The straight-grained nature of the riven stock makes mortising easier than ever. The same principles that apply to splitting apply here as well. In effect the chisel is entering the wood directly on either the radial or tangential plane.
Chop the mortise to a depth of about 1-1/2″. It’s easiest to get that depth at the middle of the mortise; at the ends it requires a little more attention. There is a tendency to pry against the end grain of the mortise – this will bruise and deform the wood there. Stay away from the final ends of the mortise at first, that way you can pry against the end grain that will end up as waste. Finish up by taking cuts straight down the end grain with the back of the chisel perpendicular to the stile.
Fig. 4.14 (top) Here, the mortise’s bottom is ragged, but it doesn’t need to be much cleaner than this. The tenon will never reach that far. Fig. 4.15 (bottom) This photo and the previous one were shot between a piece of oak and a pane of plate glass. This allows a cross-section view of a chisel cutting a mortise. This experiment was quite helpful in understanding what goes on during the mortising process. Thanks to Roy Underhill for teaching us this technique.
To get the last bits out at the bottom of the mortise’s ends, chop straight down into the ends, then turn the chisel around, and with the bevel down, drive the chisel into the midst of the mortise, and come toward the ends. Now bring up the chip on the back of the chisel.
