The Ceresilk tarp
Posted: Mon Oct 05, 2020 7:38 pm
A while back I looked into oiled silk as an option for lightweight, water-resistant material for something like a sheltercloth or cloak. Silk is attested in the literature, though a tarpaulin made of that fabric may admittedly be a bit like a solid-gold frying pan, for all we know. Deciding that that particular level of ambiguous authenticity would be offset by the protection from hypothermia such an item could provide, I decided to go ahead and make one.
I started with 6 yards of 45†wide (5.5m x 1.15m) spun silk broadcloth—23 momme/3.15 oz/100g/m². I used an acid dye to dye it green, soaking it only briefly and unevenly to produce a mottled pattern that would hopefully be more unobtrusive in the underbrush. It came out rather light and undersaturated, but I expected—correctly, it turned out—that it would darken considerably with the application of my waterproofing agent.
I then cut it in half with the aim of making a finished piece half the length and twice the width of the original cloth. I sewed the two halves together with a flat felled seam, then hemmed the entire edge. All the stitching was done with silk thread, because why not. The tarp came out to 6’6†x 8’5â€, (2m x 2.6m). The total weight of the finished cloth was about 1lb8oz, or 680g…which, for those of you fastidious enough to check that against the numbers above, makes it even lighter than the listed weight of the cloth would suggest.
It was at this point I decided to wax it. I used a mix of 2 parts beeswax and 1 part lanolin, though this came out a bit tackier than I’d like. I might halve the amount of lanolin next time, or forego it altogether. It definitely makes the dressing more pliant and plastic, less prone to cracking at creases, but the texture of the cloth is rather tacky and greasy when warm. At least it’s lovely on your hands…
Permeating the cloth proved…challenging. Coating a large area of cloth with just enough wax, but not too much, when it's dripping messily and hardening even as you try to apply it...even after my best efforts with a brush, it was highly uneven—caked in some places, totally dry in others. In order to get an even distribution of wax, I folded it up tightly, endeavoring to sandwich dry areas between caked areas. I then used the traditional primitive technique of sealing it up inside a vacuum bag and throwing it in a stewpot of boiling water for 45 minutes. (sitting my folded-up bundle in a warm oven for a long time could’ve had a similar outcome, but would’ve been messier and run a higher risk of damaging the cloth).
When I unsealed it, it was pretty much perfect. The wax had coated every square inch (6.542cm²) of the cloth, and made the color dark and even. It’s also much more waterproof than my test swatches indicated—rather than the “soaks through but at least doesn’t drip†level of waterproofing I saw with this cloth previously, water just beads off the surface, maybe due to more dressing. The tradeoff is that it’s not as self-extinguishing as more lightly-waxed silk; this will sustain a flame, unlike the previous test swatch, though it’s still much more fire-resistant than, for example, polyurethane-coated nylon. The wax also muted the slight sheen the silk had prior to treating, making it look a lot less out-of place in an outdoorsman’s kit.
Then it was time for the grommets. 2-part rivet-style grommets are neither authentic nor robust, so I bought some ¾†(2cm)Ø cast brass rings and embroidered them to the cloth. Rather than cut out a circle from the cloth within the ring and in so doing leave an uneven fraying edge, I cut an X, folded the tabs back over the ring and embroidered another layer of silk thread over the ring to keep them in place. These grommets are incredibly strong and wide enough to easily accommodate a whittled stake or a bight of my rope. I put one at each corner and one on each edge equidistant between the corners. I may also add a tie-out at the center point, haven’t yet decided.
My one worry is that the thread is a bearing surface on the inside of the ring, and sewn as a continuous loop all the way around its circumference. If it frays to breaking at any one point, it could unravel all the way around. Not 100% sure what to do about that.
The final weight of the tarp is 2¾lbs (1.25kg), meaning it’s more wax than cloth. That’s incredibly light for something using only historical-ish materials.
How is it justified in the context of Third-Age Eriador? Simple: I don’t want to die in the 21st century Sierra Nevada. But if I have to put a backstory to it, Moardon, my character, served as a member of the southern dúnedain in his younger days. If a tarp like this could be found anywhere in Middle Earth, I’d say it’d be issued to the Gondorian special forces, Gondor being relatively wealthy and well-connected in terms of trade routes. Alternately, Moardon might’ve commissioned it when working as a caravan guard and traveling scribe around Dale after leaving the military
One way or another, this is a fantastic piece of kit that I expect to last a long time and work quite well while still allowing for light, fast foot travel, free of too great a burden of weight.
I started with 6 yards of 45†wide (5.5m x 1.15m) spun silk broadcloth—23 momme/3.15 oz/100g/m². I used an acid dye to dye it green, soaking it only briefly and unevenly to produce a mottled pattern that would hopefully be more unobtrusive in the underbrush. It came out rather light and undersaturated, but I expected—correctly, it turned out—that it would darken considerably with the application of my waterproofing agent.
I then cut it in half with the aim of making a finished piece half the length and twice the width of the original cloth. I sewed the two halves together with a flat felled seam, then hemmed the entire edge. All the stitching was done with silk thread, because why not. The tarp came out to 6’6†x 8’5â€, (2m x 2.6m). The total weight of the finished cloth was about 1lb8oz, or 680g…which, for those of you fastidious enough to check that against the numbers above, makes it even lighter than the listed weight of the cloth would suggest.
It was at this point I decided to wax it. I used a mix of 2 parts beeswax and 1 part lanolin, though this came out a bit tackier than I’d like. I might halve the amount of lanolin next time, or forego it altogether. It definitely makes the dressing more pliant and plastic, less prone to cracking at creases, but the texture of the cloth is rather tacky and greasy when warm. At least it’s lovely on your hands…
Permeating the cloth proved…challenging. Coating a large area of cloth with just enough wax, but not too much, when it's dripping messily and hardening even as you try to apply it...even after my best efforts with a brush, it was highly uneven—caked in some places, totally dry in others. In order to get an even distribution of wax, I folded it up tightly, endeavoring to sandwich dry areas between caked areas. I then used the traditional primitive technique of sealing it up inside a vacuum bag and throwing it in a stewpot of boiling water for 45 minutes. (sitting my folded-up bundle in a warm oven for a long time could’ve had a similar outcome, but would’ve been messier and run a higher risk of damaging the cloth).
When I unsealed it, it was pretty much perfect. The wax had coated every square inch (6.542cm²) of the cloth, and made the color dark and even. It’s also much more waterproof than my test swatches indicated—rather than the “soaks through but at least doesn’t drip†level of waterproofing I saw with this cloth previously, water just beads off the surface, maybe due to more dressing. The tradeoff is that it’s not as self-extinguishing as more lightly-waxed silk; this will sustain a flame, unlike the previous test swatch, though it’s still much more fire-resistant than, for example, polyurethane-coated nylon. The wax also muted the slight sheen the silk had prior to treating, making it look a lot less out-of place in an outdoorsman’s kit.
Then it was time for the grommets. 2-part rivet-style grommets are neither authentic nor robust, so I bought some ¾†(2cm)Ø cast brass rings and embroidered them to the cloth. Rather than cut out a circle from the cloth within the ring and in so doing leave an uneven fraying edge, I cut an X, folded the tabs back over the ring and embroidered another layer of silk thread over the ring to keep them in place. These grommets are incredibly strong and wide enough to easily accommodate a whittled stake or a bight of my rope. I put one at each corner and one on each edge equidistant between the corners. I may also add a tie-out at the center point, haven’t yet decided.
My one worry is that the thread is a bearing surface on the inside of the ring, and sewn as a continuous loop all the way around its circumference. If it frays to breaking at any one point, it could unravel all the way around. Not 100% sure what to do about that.
The final weight of the tarp is 2¾lbs (1.25kg), meaning it’s more wax than cloth. That’s incredibly light for something using only historical-ish materials.
How is it justified in the context of Third-Age Eriador? Simple: I don’t want to die in the 21st century Sierra Nevada. But if I have to put a backstory to it, Moardon, my character, served as a member of the southern dúnedain in his younger days. If a tarp like this could be found anywhere in Middle Earth, I’d say it’d be issued to the Gondorian special forces, Gondor being relatively wealthy and well-connected in terms of trade routes. Alternately, Moardon might’ve commissioned it when working as a caravan guard and traveling scribe around Dale after leaving the military
One way or another, this is a fantastic piece of kit that I expect to last a long time and work quite well while still allowing for light, fast foot travel, free of too great a burden of weight.
it looks great 