I show you how to make a robust, versatile tarp from oilskin, that will be of great use for any camp setup, through a wide range of character concepts.
Things are either animal, vegetable or mineral. In this case cotton, a vegetable, so we want to treat it with a vegetable. Linseed oil, turpentine, alcohol, beeswax artist oil paint made of linseed oil base with tint are all ok. Any kind of petroleum product or mineral spirits is mineral and it will attack the fiber and weaken it over time. Good job here. Thanks for the video
You can use naphtha mixed with silicone. The silicone dissolves into a solution that is carried into the threads by the naphtha. The naphtha evaps completely in about 2 hours, leaving just the silicone, which is inert and does not harm fabrics. Also, it will be ready to use in about 4 hours of drying. I recommend an addtional coating be applied by roller onto the "out" side while the tarp is setup and stretched normally, to fill any crossover holes and any stitches. Emphasis on the stitch lines, as you would with any seam treatment. I have made about a dozen tarps, both canvas and cotton sheets using boiled linseed oil/mineral spirits/toilet ring "wax". They have covered my sailboats, and served well as camp tarps, and firewood covers, as well as camping table covers and a couple rain coats for my dog. This, over the last ten years. None of them has ever degraded whatsoever, and, once fully cured, they do not catch fire. NOTE: NEVER tightly roll up or fold and store any fabric treated this way until fully cured out. This can take up to several weeks. Until it is fully cured, it CAN combust on its own. This is why I recently switched to using the silicone/naphtha solution.
Vegetable was treated with mineral and eventually became mineral. Same as when you over oil a rifle or shotgun action and the oil seeps into the stock and eventually mineraluzes the wood changing the grain structure and weakening it
Hi LarpWright - very interesting - but you miss out telling us something important: what is the weight of the finished product compared to the starting product (the canvas without the proofing)? This is obviously important for anyone wishing to use a canvas tarp for backpacking. I calculate from what you do tell us (and assuming all the white spirit/mineral alcohol evaporates off) that you end up with a weight that is roughly twice what you began with. But it would be nice if you could confirm this. (Commercial canvas oilskins seem to be able to get away with a finished product roughly one and a half times the starting weight of canvas, but it is not likely that a DIY product can compete with that.)
that is a really nice tarp, good job :) also from a chemical point of view, your choice to thin it with alcohol instead of mineral spirits was a very good one, because alcohols fully dry without leaving behind residual toxic chemicals and nasty smells, where as the tarp would have probably much more flammable and never stopped smelling of mineral spirit if you had used that
I had not thought about that. But you are probably right. By now the tarp is fully dry, not even slightly greasy to the touch or anything, and all it smells of is linseed oil.
I've just oilskinned a 180gsm cotton/polyester sheet. I used vinegar as the solvent. I'll let everyone know how I get on, it might be too thin gsm but we'll see
@@larpwright no smell of vinegar. I gave it two coats as it wasn't that waterproof with 1 coat. With 2 coats it holds water, but some water can penetrate at the start (either I didn't give it two even coats, which I doubt as it looked fine, or the cotton needed to swell a little as I could see some tiny gaps). Strength wise I haven't tested it yet, but it weighs around 1.6kg (3.5 lbs) which is heavier than I wanted, but I guess that's the nature of oilskin. I'll test it camping, but even if a little water comes through, the angle it'll be at shouldn't allow it to drip onto me.
Would you not simply lay the two fabrics together so the edge fold it over and sew it a second time that way you don't have to push all that fabric through the inside of your sewing machine
www.kanirope.de/ They make high quality rope of many kinds. Very happy with that hemp rope so far. They also make tarred hemp rope, which I would have preferred, but I did not want to buy 220m of that stuff.