How to rot proof canvas?

[NickW]

Hullo,

I'm new to this forum having been directed here by the folks on the Wooden Boat Forum. I created a thread http://forum.woodenboat.com/showthread.php?163275-How-do-you-rot-proof-canvas-%28canoe-related%29 there with the same title as this one and they recommended I ask here. So,

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

 

[Rob Stevens]

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)

 

[NickW]

Rod

Thanks for that. In the UK, Cuprinol products do not seem to contain either Copper or Zinc Naphthenate. According to the Material Safety Data Sheets (MSDS) the products contain "hydrodesulphurised heavy naphtha" which is maybe not the same. I'm no chemist which is why I'm asking.

Nick

 

[NickW]

Just an update on this. 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.

Nick