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Thread: How do you rot proof canvas? (canoe related)

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    Default How do you rot proof canvas? (canoe related)

    Whilst browsing the net I came across this site http://www.bushcraft.ridgeonnet.com/...0tutorials.htm . As you see he is using loom state canvas to cover his canoes. My question is, how rot proof is untreated canvas? My instinctive answer is not very, so I tried a search and came up wih nothing of real value. The only reference I did come across was for a reproofing liquid that was 85% mineral spirits, 12.5% inorganic fillers and 2.5% zinc naphalate which must be the active ingredient. However, the site specifically cautioned against using it on virgin canvas.

    Would something like cuprinol work, or is there something better.

    Nick

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    Default Re: How do you rot proof canvas? (canoe related)

    Untreated canvas isn't very rot resistant. We've re-canvased a canoe that I think my dad paddled in over 70 years ago and when we obtained the canoe (He didn't own it when he paddled it - it belonged to friends.) the stems, decks, seats thwarts and outwales were virtually mulch. We had difficulty getting good templates from them. However, the canvas was in pretty good shape. It was more than likely an original canvas and filled with white lead. The reason that white lead used to be such an effective component of fillers is that the white lead is toxic, so molds and mildews didn't tend to grow. We re-canvassed the canoe and used non-leaded fillers. We've re-canvassed the canoe twice in the last 15 years as the new filler material doesn't lead to good rot resistance of the canvas. So, if white lead (lead carbonate) filler is available to you, I'd use it, but dispose of it carefully.

    IIRC, there are some "treated" canvas materials available, but I don't recall who was selling them here in the US - I don't know if the treatment chemicals would make it difficult to import into the UK. I'd suggest that you go ask this question over at the WCHA website's forum. The brain trust over there will have better suggestions.

    An alternative is to use polyester fabric (Dacron) as a covering material. It will look "traditional, but will be totally rot resistant and lighter weight. The downside is that you might not find it to be as tear-resistant.
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    Default Re: How do you rot proof canvas? (canoe related)

    Tanbark is the old method. But, it contains a lot of, now, hard to find items in the mix. This might be a better approach.
    http://tweetys.com/canvas-preservative.aspx
    Jay

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    Default Re: How do you rot proof canvas? (canoe related)

    Jay, Is the Canvak a sort of waxy finish? That might make it harder to fill and paint the canvas on the canoe - think like you were putting canvas over a deck.
    "The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
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    Default Re: How do you rot proof canvas? (canoe related)

    Sorry, I can't say, I only googled the info on your behalf. I would suggest you contact the mfg. I trust that they would give you the best advise.
    Jay

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Jay Greer View Post
    Sorry, I can't say, I only googled the info on your behalf. I would suggest you contact the mfg. I trust that they would give you the best advise.
    Jay
    Well, I asked because it looks like a product that we applied using a sprayer to tents and tarpaulins at a summer camp where I worked. It was to prevent moisture absorption in shady locations where the mold and mildew would result in rot of the canvas that was referred to as "shotgun canvas" - the rot holes looked like someone took a load of buckshot to the tents. It was a waxy material and wouldn't have taken either filler or paint.
    "The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoez View Post
    Jay, Is the Canvak a sort of waxy finish? That might make it harder to fill and paint the canvas on the canoe - think like you were putting canvas over a deck.
    "Waxy solid, slight odor"
    Canvak MSDS: https://www.dialmfg.com/technical%20...ver%20MSDS.pdf
    anything made and sold in the US will have an MSDS somewhere

    Not sure which kind of boat you are looking to cover; I didn't like the results from a copper napthenate solution test on canvas. It bled, unpleasantly, when filled. So I skipped it.

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    Default Re: How do you rot proof canvas? (canoe related)

    When I replaced the canvas deck of my 60's era Melges C over 20 years ago, I was told by the folks at Melges to just use Thompsons Water Seal as a thinner to a quality oil-based exterior paint. Paint with a "thinned" coat to tighten and seal the canvas and then paint it again with just the straight exterior oil-based paint. That replacement canvas of the deck is still in good shape yet but it did need a few recoats for non-rot related issues.

    (edit) I see in another post that the old Thompsons had copper nap. in it and it no longer does.... This is maybe why it worked back then???
    Last edited by eflanders; 05-15-2013 at 10:06 PM.

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    Default Re: How do you rot proof canvas? (canoe related)

    The information you seek is in the minds of the best canoe restorers on earth and you can find them here:
    http://forums.wcha.org/forum.php

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Todd Bradshaw View Post
    The information you seek is in the minds of the best canoe restorers on earth and you can find them here:
    http://forums.wcha.org/forum.php

    +1. That's the place...
    "The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
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    Default Re: How do you rot proof canvas? (canoe related)

    Thank you all for your helpful replies. I'll try asking over at the wcha forum as suggested by several of you.

    Nick

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    Default Re: How do you rot proof canvas? (canoe related)

    Just an update. I asked my original question on the Tips and Tricks section of the WCHA forum. Rod replied that "Generic "Cuprinol" is sold here (Canada) at most hardware stores as clear or green preservative; "protects wood, canvas, and rope against rot, mould, fungus, mildew, decay and woodboaring insects". Clear contains petroleum distillates and zinc naphthenate (the green version contains 2% Copper Naphthenate). Costs $9.99 a gallon (3.78 L"

    After researching the web and looking at cans in the stores, the only Approved Biocides for wood preservation are PROPICONAZOLE, IPBC (3-Iodo-2-propynyl-n-butylcarbamate) and DICHLOFLUANID. I'm guessing that both Copper and Zinc Naphthenate are now banned products (or at least non-Approved) in the UK and I imagine the same is true for the rest of the EU.

    BTW, the active ingredient in both Clear and Green Cuprinol sold in the UK is PROPICONAZOLE. So I'm guessing that Cuprinol is a global brand but with different formulation to comply with different regulatory regimes.

    Nick

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoez View Post
    It was more than likely an original canvas and filled with white lead. The reason that white lead used to be such an effective component of fillers is that the white lead is toxic, so molds and mildews didn't tend to grow. ... So, if white lead (lead carbonate) filler is available to you, I'd use it, but dispose of it carefully.
    Unless you can provide some scientific authority for your assertion... it would be best to quit perpetuating this myth. It's funny, really. If you google "lead" and "mildewcide" or "fungicide," you start seeing results from the WBF. It seems to be something of a localized fantasy. Lead isn't toxic to fungus or molds and mildews. Lead oxide doesn't "kill" rot or mold because it isn't "toxic" to fungi or molds. (It isn't really toxic to humans, either, unless you eat huge amounts of it. Eating smaller amounts of it can make you stupid, but if your into eating lead paint chips, you're already stupid and, as they say, "You can't fix stupid." so why worry?)

    It's just that people mistakenly presume lead based paint is a mold and mildewcide because mold grows on latex paint like all get out and doesn't grow as much on lead based paint. The reason for the difference in the two isn't that lead oxide pigment is "toxic" to anything, but rather that the latex coating is much more porous than oil based coatings, holds moisture much more readily, and thus is far more hospitable to mold and fungus growth. So, a tip for everybody's next science fair project: "Seeds sewn in a Dixie cup of rock didn't grow. Seeds sewn in a Dixie cup of potting soil did grow. Ergo: Rocks are toxic to seeds." isn't going to win you any prizes!

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Bob Cleek View Post
    Unless you can provide some scientific authority for your assertion... it would be best to quit perpetuating this myth. It's funny, really. If you google "lead" and "mildewcide" or "fungicide," you start seeing results from the WBF. It seems to be something of a localized fantasy. Lead isn't toxic to fungus or molds and mildews. Lead oxide doesn't "kill" rot or mold because it isn't "toxic" to fungi or molds. (It isn't really toxic to humans, either, unless you eat huge amounts of it. Eating smaller amounts of it can make you stupid, but if your into eating lead paint chips, you're already stupid and, as they say, "You can't fix stupid." so why worry?)

    It's just that people mistakenly presume lead based paint is a mold and mildewcide because mold grows on latex paint like all get out and doesn't grow as much on lead based paint. The reason for the difference in the two isn't that lead oxide pigment is "toxic" to anything, but rather that the latex coating is much more porous than oil based coatings, holds moisture much more readily, and thus is far more hospitable to mold and fungus growth. So, a tip for everybody's next science fair project: "Seeds sewn in a Dixie cup of rock didn't grow. Seeds sewn in a Dixie cup of potting soil did grow. Ergo: Rocks are toxic to seeds." isn't going to win you any prizes!
    White lead is insoluble in water, and I'm pretty sure that the old timers weren't using latex paints as the filler "base", so I'll certainly buy the fact that it will help prevent water absorption by the canvas. My experience with filler and coating is oil based enamel and two bouts of "lead-free" filler, otherwise. When removing canoe canvas, I can't say that I've seen the filler get consistently to the inner surface of No. 10 canvas.

    However...

    Bob - you need to be looking at "anti microbial", not "mildewicide" or "fungicide". You should turn up better information that way.

    Lead and it's compounds including Lead Carbonate (White Lead) are known neurotoxins, so yes it is toxic. In the ancient world - Egypt, Greece, Rome and Europe, Lead Carbonate was used as both a pigment and, unknown to those who developed it at the time, a very potent anti microbial agent. Basically, the cosmetics didn't support microbial growth. This has been long known in the cosmetics and pharmaceutical industry. When I was working in the industry, there were companies using arsenic, silver, copper and lead compounds to fabricate anti-microbial packaging materials - one of which was, Lead Carbonate. I'm not a chemist, so I can't say how they were making this not be toxic to the end user, but they were "bonded" with the polymers. I'm sure some of this is still trade secret, but it's not uncommon to see mold and mildew resistant materials with the silver compounds.

    Jerry Stelmok was the person who pointed out the benefits of white lead fillers for canvas in terms of it's longevity for canoes. I'd venture that he's seen many more than you or I, so I'll trust his anecdotal Dixie Cups based on what I know from the experience working in cosmetics.
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    Default Re: How do you rot proof canvas? (canoe related)

    Here is some science, and there is quite a bit of it out there, the more I read the more seriously I take it.

    Canoez has it... thank you for helping me understand it.
    Search > anti microbial properties + (Pb) Lead .

    Lead is nasty toxic stuff. Although the end result in a human may only be a reduced IQ, it seems unfair to label a child or a baby "stupid" because it has ingested microscopic amounts of lead dust from an ordinary household.

    http://www.ncbi.nlm.nih.gov/pubmed/20938849
    In this study, nine pure metals, viz. titanium, cobalt, nickel, copper, zinc, zirconium, molybdenum, tin, and lead have been tested for their antibacterial properties against two bacterial strains, Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli

    http://www.nature.com/nrmicro/journa...micro3028.html

    Metals have been used as antimicrobial agents since antiquity, but throughout most of history their modes of action have remained unclear. Recent studies indicate that different metals cause discrete and distinct types of injuries to microbial cells as a result of oxidative stress, protein dysfunction or membrane damage.

    http://quizlet.com/20151815/the-anti...s-flash-cards/
    This one is interesting, and dumbed down enough even for me...

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoez View Post
    White lead is insoluble in water, and I'm pretty sure that the old timers weren't using latex paints as the filler "base", so I'll certainly buy the fact that it will help prevent water absorption by the canvas. My experience with filler and coating is oil based enamel and two bouts of "lead-free" filler, otherwise. When removing canoe canvas, I can't say that I've seen the filler get consistently to the inner surface of No. 10 canvas.

    However...

    Bob - you need to be looking at "anti microbial", not "mildewicide" or "fungicide". You should turn up better information that way.

    Lead and it's compounds including Lead Carbonate (White Lead) are known neurotoxins, so yes it is toxic. In the ancient world - Egypt, Greece, Rome and Europe, Lead Carbonate was used as both a pigment and, unknown to those who developed it at the time, a very potent anti microbial agent. Basically, the cosmetics didn't support microbial growth. This has been long known in the cosmetics and pharmaceutical industry. When I was working in the industry, there were companies using arsenic, silver, copper and lead compounds to fabricate anti-microbial packaging materials - one of which was, Lead Carbonate. I'm not a chemist, so I can't say how they were making this not be toxic to the end user, but they were "bonded" with the polymers. I'm sure some of this is still trade secret, but it's not uncommon to see mold and mildew resistant materials with the silver compounds.

    Jerry Stelmok was the person who pointed out the benefits of white lead fillers for canvas in terms of it's longevity for canoes. I'd venture that he's seen many more than you or I, so I'll trust his anecdotal Dixie Cups based on what I know from the experience working in cosmetics.
    Lead is a good paint pigment, but when it sands, chalks, or flakes, it poses some theoretical hazard to ingestion by humans, particularly children because they may be attracted to the sweet taste of it and because, due to their smaller body mass, smaller amounts have greater negative effects. That said, it is the lead in combination with the stomach acids that makes it possible for the lead to find it's way into the bloodstream. The overwhelming number of people who die from "lead poisoning" do so from over-exposure to lead in the form of bullets than in any other way.

    I think if you consider an intact lead based paint coating, you'll find that the lead pigment is not going to have much of any negative effect on fungus because the lead pigment is encapsulated in cured oil. My point was that a lot of people think it does (and perhaps to some small, theoretical extent, it might, but not so's you'd notice it) because latex paint is so prone to growing mold for the reasons I stated. It wasn't because lead kills mold, but because latex welcomes it.

    White lead is, however, excellent for use on canvas of any type in the marine environment. Any good marine enamel should give you pretty much the same results though. There's no magic in the white lead itself, except that it was the best white pigment known to man.
    Last edited by Bob Cleek; 05-27-2013 at 12:00 AM.

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoeyawl View Post
    Lead is nasty toxic stuff. Although the end result in a human may only be a reduced IQ, it seems unfair to label a child or a baby "stupid" because it has ingested microscopic amounts of lead dust from an ordinary household.

    ..
    It certainly would be unfair to label a child or a baby "stupid" because it had ingested microscopic amounts of lead dust from an ordinary household.

    The exposure can be cumulative, but it takes a whole lot more than "microscopic amounts" to produce any measureable negative effects.

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    Default Re: How do you rot proof canvas? (canoe related)

    "children with blood lead concentrations greater than 10 μg/dL are in danger of developmental disabilities"

    That would be 10 millionths of a gram of lead in 10 litres of blood - not so much ...

    wiki

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoeyawl View Post
    "children with blood lead concentrations greater than 10 μg/dL are in danger of developmental disabilities"

    That would be 10 millionths of a gram of lead in 10 litres of blood - not so much ...

    wiki
    Here in NZ in areas of old housing that have been gentrified there has been a measurable increase of lead in children because so much lead was used in paint and then sanded off in the renovation process years later.

    These days there is now a lot more caution surrounding the renovation of old painted houses.
    There is nothing quite as permanent as a good temporary repair.

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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Bob Cleek View Post
    Lead is a good paint pigment, but when it sands, chalks, or flakes, it poses some theoretical hazard to ingestion by humans, particularly children because they may be attracted to the sweet taste of it and because, due to their smaller body mass, smaller amounts have greater negative effects. That said, it is the lead in combination with the stomach acids that makes it possible for the lead to find it's way into the bloodstream. The overwhelming number of people who die from "lead poisoning" do so from over-exposure to lead in the form of bullets than in any other way.

    I think if you consider an intact lead based paint coating, you'll find that the lead pigment is not going to have much of any negative effect on fungus because the lead pigment is encapsulated in cured oil. My point was that a lot of people think it does (and perhaps to some small, theoretical extent, it might, but not so's you'd notice it) because latex paint is so prone to growing mold for the reasons I stated. It wasn't because lead kills mold, but because latex welcomes it.

    White lead is, however, excellent for use on canvas of any type in the marine environment. Any good marine enamel should give you pretty much the same results though. There's no magic in the white lead itself, except that it was the best white pigment known to man.
    In regard to any good marine enamel giving you the same results versus a filled canvas with white lead, I'll have to say, no.

    Let's think about the construction difference between a canvas covered deck with a marine enamel coating and a canoe with the same coating.

    A canvas covered deck presents it's finished surface to the elements with what moisture it gets from the underside coming from moisture in breath or the damp inside the cabin/hull. That moisture is more than likely driven off every time the sun warms the cabin top.

    Canoes are a different kettle of fish. The hull is an upturned cup that will get water, sand, rain and other debris between the planking and the canvas. They see much more liquid water than the underside of a canvas deck. When constructing the canoe, the planking on the outside of the hull gets a wash of linseed oil and turpentine before canvas is applied. This isn't the best mixture for not feeding microbes. The wood is generally white or red cedar which has natural rot resistance. Filler is then applied with a roller or stiff brush and rubbed in using a canvas mitt to give a smooth slate like surface. Primer and then an enamel paint are then applied. Porch and floor enamel has been a popular choice. When removing canvas from canoes you can see that the canvas isn't fully penetrated with the filler - the inside surface has areas where the raw canvas is visible.

    Canoes are not used the way boats that sit in the water are - they go through cyclic wet/dry periods which I'm sure helps with the growth of molds/mildews. As I noted above, the water gets to that raw canvas from the inside can be in large and regular quantities which will support the growth of molds an mildew resulting in the deterioration of the canvas. We applied unleaded canvas filler to an untreated No. 10 canvas on a Chestnut canoe that we than applied primer and oil-based enamel paint to. This canoe we removed a leaded canvas from - the age was determined based on the paint colors/layers - the inner surface of the original canvas was stained, but in good shape. This has been observed by many, many canoe restorers. The canoe was well stored with the unleaded filler, but has been replaced twice since we've owned it. Since we used good enamel on the outside, it should have lasted well, right? The only thing different is the white lead in the fillers that I can think of.

    Oh, and the health hazards shouldn't be ignored by any means.
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    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Canoeyawl View Post
    "children with blood lead concentrations greater than 10 μg/dL are in danger of developmental disabilities"

    That would be 10 millionths of a gram of lead in 10 litres of blood - not so much ...

    wiki
    That's right about the not much part, but a dl is not a Dl. dl is deciliter, not Dl, dekaliter, so it is 100 millionths of a gram in 1 liter of blood. Any way you look at it, 100 parts per billion is a pretty small amount. That block of lead dissolved in that liter was 0.0008 inch on a side.

    Lead is a neurotoxin, and last time I checked, the mold wasn't nervous. I think Bob is right about the lead being sufficiently encapsulated to be a largely ineffective biocide and still insufficiently encapsulated to be safe.

    Another good word to Google here is oligodynamic. http://www.tested.com/science/life/4...kill-bacteria/ for instance.

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    Default Re: How do you rot proof canvas? (canoe related)

    Thanks for the correction Dave - I was hoping someone would straighten me out.
    I'm way over my head here... (But .0008"? I know what that is.)
    What little I did read (google) indicated that lead did have an oligodynamic action with many microbes.

    Having fooled around with lead for most of my life, I am cautious now, but for many years I was very cavalier about it.

    The first house that my parents bought had lead plumbing in most of it, and the municipal water supply pipes were also lead (and still are - I know this now). As a child I exhibited many of the classic symptoms of lead poisioning and much worry (and money, I suspect) was spent to try and understand why, but (lead) poisioning never came up. As a 7 year old I certainly had no idea, and in early 1950's America it was not on the radar screen. These days I get my blood work done every two years for lead, cadmium, mercury, and chrome along with the "normal" stuff. (I still do a lot of welding, and some casting along with my appetite for fish)

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    Default Re: How do you rot proof canvas? (canoe related)

    Modern marine enamel lasts upwards of 7-10 years on a trailered wood boat in the sub-tropics. High UV, heat, humidity, torrential rains etc. Wood fiber is a heck of a lot less homogeneous than canvas fiber, just considering arrangement alone.

    This is what gets me about many topics on this board. What exactly is a canoe, in modern times, going to be subjected to as far as the duty it will see. I bet 95% of the time, it spends it's life upside down in a yard, or under a tarp or overhang. Don't wash the paint out of that natural bristle brush one time and all the leaving it out to the weather in the world isn't going to rid of it in our lifetime.

    If there is ever an occurrence of frequent overkill and over-thought, it's on these boards where imaginations run wild of extremes that are rarely encountered these days, and if they indeed do exist, it's most likely on the heels of pinching pennies and lack of experience with application. Another gremlin is the habits born of lack of traditional maintenance practices once novelties wear off, with everything else around us able to be renewed with a shot from the garden hose once or twice a year.

    Quality oil based enamel is some pretty rugged stuff. I've seen drop clothes that were washed in TSP still come out with the enamel stains still intact, minus the gloss perhaps.

    A better approach to this question might be, "I have spilled enamel paint on my canvas and it dried there and I would like to know how to get it off." Most would say they don't know how to get it off, at least without the use of caustic or volatile solvents.

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    Default Re: How do you rot proof canvas? (canoe related)

    I think that most of you are missing the point about the antimicrobial properties of the various metals (metal salts/oxides, etc.) that were discussed previously. These metals are providing antimicrobial effects even though they are encapsulated in other materials. A good example that is readily available commercially is polyethylene cutting boards that contain silver compounds that provide anti-microbial effects even though they are embedded in the plastic. Go check them out at your local Target store.

    As I noted, I was in the cosmetics business and worked for a firm that primarily made mascara containers. One common problem is contamination by molds and bacteria on the skin/lashes that leads to product contamination by the growth of molds and bacteria in the product. The vendor of our nylon brush fibers had developed sample fibers that contained either arsenic, silver, copper and lead compounds. The compounds were embedded in the plastic fibers and couldn't leach from the product to contaminate product or user - as I said before, they were "bound" in a way that I don't fully understand. I was witness to a presentation by the vendor to show the effectiveness of their product's antimicrobial properties which showed slides of petri dishes that had agar in them. The dishes were contaminated with either bacterial culture or mold spores. On one half of the dish, there was nothing. On the other half of the dish were 5 or 6 neatly spaced pieces of the fiber. Plainly seen was the fact that on the half of the dish with fibers, microbe growth was inhibited to varying degrees depending on the type of antimicrobial additives/% loading. On the plain side, the microbes went wild creating colonies. I'd say that was pretty good evidence that the encapsulated materials were still effective antimicrobials.

    So, the fact that the lead carbonate is embedded in the paint doesn't seem contradictory to me in the ability to still have antimicrobial effects.

    While it is great to talk about the effectiveness of quality oil-based enamel paints, both marine and commercially available products, it is important to remember that the inside surface of a canoe's canvas isn't coated with the enamel and that's the place where moisture gets to the canvas. Also, I don't think storage or handling of wood and canvas canoes has changed much over the past hundred years. People keep them in barns, garages or outside on sawhorses, so I don't see much change there. What has changed significantly in the past 20-30 years is the reduction in the use of white lead fillers in covering canoes because of health concerns regarding the lead and the availability of the material.
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    Default Re: How do you rot proof canvas? (canoe related)

    My 1957 Old Town "Freighter" still has the original canvas, but its' time is about up. I've been considering synthetic because the expense of white Lead paste, but I want something much heavier than "aircraft fabric" and consequently have done nothing. Another fifty years of service would suit me, but only ten years - forget it.
    The existing canvas on the canoe is about 1/32" thick and the white lead paste is again that thick, and the canvas is well saturated with the white lead.

    This thread makes a good argument for Copper plumbing, Silver-ware, and Brass doorknobs.

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    Default Re: How do you rot proof canvas? (canoe related)

    Well, look to George Dyson over at Dyson, Baidarka & Company - he sells some nice polyester fabrics in heavy weights (8oz and up) which would be suitable for covering the canoe when you're ready. Nice part about the polyester is that it heat-shrinks a little bit with an iron. Also, look to Alex Comb's article on how he does it at his website. No personal interest in either business, BTW.
    "The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
    -William A. Ward



  27. #27
    Join Date
    Mar 2005
    Location
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    Default Re: How do you rot proof canvas? (canoe related)

    We all have had to make adjustments around the FDA and EPA. For every material that has been banned, there is 10 that sort of work. What it comes down to, if it matters that much is, we have to dry our boats out, and there is antimicrobial properties in a couple cap fulls of bleach in the wash water.

    I soak my own boat inside and out in use, and again when I wash it when I get home and it sits uncovered for a day drying out before the tarp goes back on the next day, and there is no mold, while living in the mildew capitol of the world. The only nagging problem is trying to wash off the dried spider poop if I have let the boat sit too long.

    I know of some folks who love building and tinkering so much, that they go through withdrawals once the project is over and are even inventing things to go wrong so that they can touch things up or do things over at some point, otherwise, they are sitting around like the Maytag repairman.

    People that are looking for decades of carefree service, usually opt to purchase plastic or fiberglass boats, and even gel coat needs love at some point. Many of you live in the colder climates where you are cabin bound for months at a time. I'd go stark raving nuts with nothing to do with my sanding block and 14 layers of insulation on and my boat would be like new every year come Spring.

  28. #28
    Join Date
    Jun 2000
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    Madison Wisconsin
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    10,355

    Default Re: How do you rot proof canvas? (canoe related)

    I think you are over-thinking this one. The predominant factor in the life of your canvas (and the entire wood/canvas canoe) is not the amount of mildewcide that the canvas may or may not contain, it is how you store the canoe. The vast majority of its life, you won't be in it and it has to be somewhere. The major ingredient in canoe filler, old or new, is not lead, it is powdered flint, silica or some other mineral substance that will yield a hard, smooth surface. I have an unopened gallon can of genuine Old Town canoe filler from the early 1970s and it weighs 13 lbs. If it contains any sort of lead, I'm sure it is a minor portion of all that weight.

    Wooden canoes do soak up bilge water that seeps down through the planking gaps in use - but with proper storage, it will dry out when not in use, and the fact that cotton canvas will tend to wick and spread moisture actually helps move the moisture to places where it can escape. If you can find a mildew-treated canvas that won't repel your filler, that's great, but if not, you can still expect a very decent life span with regular canvas and modern, lead-free filler recipes, just by having good storage available.

  29. #29
    Join Date
    May 2004
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    Cuyahoga Falls, Ohio
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    Default Re: How do you rot proof canvas? (canoe related)

    Toxic to microbes? I thought we were worried about fungus.
    And Cleek didn't say the very young are stupid, although some percentage probably are. My reading was that if you are eating paint chips, you're already stupid.
    These questions sure do elicit responses that wander hither and yon. He wants to know how to keep cotton canvas from rotting.
    Asked and answered, I'd say. On some time scale or other, cotton is temporary. Aren't we all?

  30. #30
    Join Date
    Jun 2003
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    Central Coast, Ca
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    32,963

    Default Re: How do you rot proof canvas? (canoe related)

    Quote Originally Posted by Tom Robb View Post
    Toxic to microbes? I thought we were worried about fungus.
    My reading was that if you are eating paint chips, you're already stupid.
    Fungi are Microbes...

    "Children are more at risk for lead poisoning because their smaller bodies are in a continuous state of growth and development. Lead is absorbed at a faster rate compared to adults, which causes more physical harm than to older people. Furthermore, children, especially as they are learning to crawl and walk, are constantly on the floor and therefore more prone to ingesting and inhaling dust that is contaminated with lead."

  31. #31
    Join Date
    Sep 2007
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    Northeast
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    Default Re: How do you rot proof canvas? (canoe related)

    Another factor with children ingesting lead is that it has a sweetness to it. IIRC, the Romans added lead to wine for that reason.
    "The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails."
    -William A. Ward



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