Making of a Leather Mug

Drinking vessels made from animal hides have a long history, going at least as far back as the neolithic period - a crude leather cup was found in a stone age context in London, England, for example. Hide vessels hung on in use long after earthenware, metal and glass came on the scene. There have even been found clay bottles, shaped and glazed in such a way as to the mimic the look of a leather vessel, down to finely inscribed stitching.

Leather vessels were at their most popular in the British Isles, particularly England. Here we see the leather bottles, flasks and blackjacks that evoke images of British sailors and pirates, quaffing grog or ale on the high seas. Sturdy leather drinking vessels go back at least to the Saxon period, and by the 14th century there was a guild of bottle makers in London, specializing in crafting drinking vessels of leather.

If you're going to an SCA  event, a leather mug will serve you well as your quaffing implement.

Quaffing. Not even once.

But then, you're here to find out how it's made...
 

Well, I have to begin with this: the mugs (or jacks) I make are not particularly historical. Most of the surviving examples are tapered, being larger on the bottom to be more stable aboard ship. And the handle shape is just something I thought would be most comfortable. The traditional jacks would have been made from harness thickness leather, about 30-50% thicker than the leather I use. And the waterproof lining would have most likely been a pine, spruce or birch derived black pitch, whereas I use a combination of pine gum rosin and beeswax that is golden in colour.

That being said, the materials I use, and the general techniques, are pretty close to crafters from the Middle ages. And the end result would not look out of place in a medieval setting.

It all starts with a pattern. You can find numerous mug patterns online, but after looking at several I decided to draw up my own. I've experimented with a couple of handle styles and found I liked the D shape, so that's what I used. As far as sizing, I found a convenient form to use for the leather - a glass honey jar of just about the right size and shape. From the measurements of the jar I laid out the pattern on bristol board, complete with an over sized bottom piece and a filler piece for the handle.

Once the pattern was cut out, I laid the pieces out on an 8/9 oz hide and marked the outlines with a scratch awl. Then, with a knife and straight edge (and great care going around the curves) I cut the pieces from the hide. This is always the most stressful part of the process for me - a slip up here can be costly.

When I've got the pieces cut out, its time to prepare them for stitching. I use the stitching gouger to cut a shallow channel into the leather along the bottom of the side of the mug, and outline the double-stitching around the mug handle. This way, when the threads are pulled tight, they will sit flush with the surface of the leather. It looks nicer and saves wear.

After that, I round the edges with an edge beveler - later, when I burnish the edges, it will form a smooth, rounded edge.

Once all the prep is done, I glue the handle parts together with contact cement. I use a minimal amount of the stuff - it smells awful and can make a mess if you're not careful, but it bonds like iron when done correctly. None of the cement ever touches the parts of the mug in contact with the drinks. I usually avoid gluing things, but previous attempts to stitch this without gluing first turned out sloppy-looking.

The glued handle assembly, complete with the handle filler piece.

While waiting for the glue to dry, I soak the bottom piece of the leather mug in water- this renders it able to be formed and moulded. For this next part I owe thanks to Angster on Leatherworker.net, who did a great tutorial on making a Tudor-style mug. (One might call it a Tudorial, eh? Eh?...well, I thought it was funny.) I mold the soaked (or "cased" leather) over the bottom of the glass jar, and then take a metal hose clamp and force it down over the leather. Then all I do is tighten the hose clamp until the leather is tight against the jar.

The bottom of the mug, forming on the honey jar.

With the bottom of the mug forming, it's time to stitch the handle. Leather hand stitching is a little different than hand stitching fabrics. You use one long piece of thread with a needle on each end. One needle is held in each hand, and the awl (a sharp, narrow-bladed tool used for making holes through the leather) is held in your third hand. You can already see the problem. With a little dexterity and some practice, you learn to hold both needles and the awl without ever setting them down.

I use linen thread, waxed with 'coad', a mixture of pine rosin and beeswax, not very different from the lining the mug will get later. This mixture prevents the thread from rotting and makes it slightly sticky. Once the threads are pulled tight, the coad melts and then solidifies on the threads in the leather, adding strength to the seam.

First you punch the hole through the leather with the awl, then pass the needle from the opposite side through the hole. Then you take your awl-hand needle and pass it through the hole, and then pull them both tight. I loop the thread around the needle on the other side, so that when the thread is pulled tight it helps align the stitches the right way and forms a knot inside the leather, increasing the strength of the seam. I'll go into a more detailed explanation of the technique in a future post, but for people who can't wait, there are dozens of excellent videos on YouTube detailing hand sewing techniques.

After that, it's rinse and repeat. It takes about 3 metres of thead to do the outer seam on the handle, and a little more than 2 metres to do the inner seam. For this part at least, I hold the mug in a "stitching pony" (a clamp that acts as a third hand) my dad made for me. Thanks Pop!

Note the awl and needle held in the same hand. Please do not note the scruffy pseudo beard.

Also, I just realized that the T-shirt I'm wearing in those pictures was a gift from my Dad too. I really am a self-made man though, I swear!

Finally, the handle is stitched. This is the longest part of the process - just the handle probably takes upwards of 2 hours.

Stitching on the handle completed

Now this part of the mug is soaked as well and forced over the honey jar, and left to dry overnight. I wiggle it around a bit on the jar to stretch it somewhat, so that it's easier to remove. The first couple mugs I made were a real pain to get off of the jar.

The next bit involves stitching in the bottom, which has dried into the shape of the bottom of the jar. This is a little trickier to do as the mug can no longer be held in the clamp. Instead, the mug has to be held between the knees while you sew. I left the honey jar in for this part, it helped the mug maintain it's shape while I sewed. Yes, this is exactly as awkward as it sounds, and I end up doing a lot of sewing like this, where a clamp can't help. Unlike some stitching ponies, mine isn't magical.

Special thanks to Red Clamp #1 - without you, this mug wouldn't have been possible.

With the bottom sewn in, the mug is (structurally) complete. Now I carefully trim and sand the edges, and burnish them with a horn folder by dampening the leather and rubbing the horn vigorously over it. Done properly, the edge loses its frayed appearance and becomes smooth.

Now we treat the mug to make it capable of holding liquids.

The first step is to soak the mug in molten beeswax. This hardens the leather to an almost plastic-like consistency and completely waterproofs the leather. From my research I don't believe anything like this was done in period. The mugs were made from very thick leather and would likely have held their shape without stiffening - besides, for most of them medieval period beeswax would have been very valuable as candles for the Church, and likely not available for making the ubiquitous leather vessels. However, I choose to harden the mug because of the thinner leather and the increased durability, as well as the waterproofing angle.

I melt the wax in a double boiler big enough that I can dip the entire mug at one time. You can do this by melting the wax, painting it onto the leather and leaving it in a hot oven, but you have to be REALLY CAREFUL, or the leather will overheat and crumple. I consider a double boiler something of an investment.

I immerse the mug in the hot wax until bubbles stop rising to the surface - this is the beeswax soaking into the leather and forcing pockets of air out. Then I remove the mug, and wipe off any excess wax with paper towels. If you leave the wax too long, it cools and becomes difficult to remove. Now the mug looks like almost finished. The beeswax darkens it substantially - partly because that's what oils and waxes do to veg-tanned leather, and partly because I use a dark beeswax.

Now, the final stage - lining the interior of the mug with the beeswax/pitch mixture. The pitch is pine gum rosin, a food safe pine resin product. It's approved as a food additive by Health Canada, often added to powdered drink mixtures (for what purpose, I honestly don't know). It bears only passing resemblance to the pitch used in actual period vessels - that pitch would have been black and more flexible. In solid form, it's crystalline and almost translucent, and looks like this. (I don't get my stuff from that site, but the people I use don't have as nice a picture). When solid, it's hard but brittle. By adding the beeswax, its easier to work with and a little more flexible. As a bonus, the melting temperature is lowered, so you can fix any cracks in the lining with a hair dryer or some careful use of the oven. Beeswax alone is too fragile in my opinion and melts in very hot weather, springing leaks easily. My original beeswax-lined leather bottles were prone to leaks, but they haven't leaked at all since I relined them with this mixture.


I measure out a 50/50 mix on a kitchen scale. This seems to work, but I may experiment in the future.

I melt the rosin inside the oven in a tin can - it takes longer than on the stovetop, but I have more control over the temperature and if there is a fire, it's contained. I set the oven to about 120 degrees celsius.

The melted rosin, ready to have the beeswax added

Once the rosin is melted, I add the beeswax, put it back in the oven and melt it in. Then I carefully stir the mixture together to make sure that the wax and rosin aren't separated. Use something you don't care about - the mix is a pain to get off.

Once everything is mixed, I carefully pour the liquid into the mug. Then it's a matter of rolling the mug around, VERY CAREFULLY, allowing the liquid to coat the full interior of the mug. I let the liquid settle extra thick on the bottom, where leaks are most prevalent. I haven't yet managed to get a perfectly smooth internal finish, but honestly it doesn't affect the function the mug at all so I don't worry about it too much.

The mug shortly after lining - the hot wax and pitch mix is still partially translucent.

Finally, while the lining is still warm, I scrape any rogue bits of pitch off the mug with the back of a butter knife and try and even out the lining as much as I can. And here's the finished product!

Overall, the process probably takes 5-6 hours, spaced over several days because of the soaking steps. The mug works great for cool liquids - but acidic liquids soften the liner a little, and high-alcohol spirits will straight-up dissolve it, so be careful! My own mug is my favourite beer glass. I've probably had a few dozen beers out of it and the lining shows no sign of deterioration. Try some traditional dark ales out of it - I think you'll like it!

If you'd like to purchase a mug like this, I have it listed on Etsy here, and a black version listed here. And if you have any unanswered questions, ask them in the comments below.

Thanks for reading!