Best canvas waterproofing

pcatterall

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I notice that my canvas cockpit cover/tent gets saturated when there is heavy rain. the rain does not penetrate but the inside surface is wet and touching it can introduce leaks.
Like some old tents that I recall !
I will need to take some waterproofing out to spain on my next visit and will appreciate suggests as to the best treatment. I prefer a spray as have no facilities for soaking such a large item.
Many thanks
 

ip485

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Renovo is the very best. I am afraid it isnt spray on (well maybe they do an aersol) but just paint it on with a brush with canvas in place. Works, lasts and pretty much colourless. Does cause slight marking on gel so worth avoiding any spills but they rub off easy enough with a little wax. The stain is unbelievably good as well if the canvas is looking a little faded.
 

PaulRainbow

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Fabsil is another good one. Available in aerosol, 1lt or 5lt. The aerosol isn't s good value as the other options and you don't want to spray it all over the boat.
 

ostra4

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I've used Fabsil for a number of years out in Med for both waterproofing and to protect from UV , I brush it on the Bimini and spray hood and do this once a season and is very effective .I also feed my in mast reeding rope through a container filled with Fabsil to try and prolong its life as bit of a pain getting a new rope in place .Iv not tried the other products mainly because the Fabsil is available in 5 litre containers at a reasonable price and does the job .
 

Quandary

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Question was 'best canvas waterproofing'?
If it is quality acrylic canvas such as Sunbrella or equivalent you should not really be using silicone proofers on it unless it is so completely shot that all traces of the original manufacturers proofing treatment has gone, silicone products are not compatible with the manufacturers treatment, though the manufacturers of these treatments won't tell you that. However there are suitable re-treatment products available, the one Sunbrella recommend for their canvas is 'Fabric Guard 303' it is available from Amazon.
But for covers that are way past their best or of dubious origin Fabsil or the others will do a job though you may have to retreat fairly frequently, probably at least once a year. You can find some reliable advice on this subject on car restoration sites.
 

Billjratt

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The Spanish use stuff called DECO-ELAST on their flat roofs, you can get it in any good ferreteria or paint shop. If you dilute it with water it becomes a milky liquid that can be painted on to canvas which will dry to the original colour but will have more 'body' and will be waterproof. Easy, cheap, local.
I brought a tub home and do my dodgers, stackpack, hatch covers etc. every few years. I also have a suspicion it helps to UV-proof the stitching which is a real bonus in your neck of the woods.(though no longer for me!)
 

thinwater

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Question was 'best canvas waterproofing'?
If it is quality acrylic canvas such as Sunbrella or equivalent you should not really be using silicone proofers on it unless it is so completely shot that all traces of the original manufacturers proofing treatment has gone, silicone products are not compatible with the manufacturers treatment, though the manufacturers of these treatments won't tell you that. However there are suitable re-treatment products available, the one Sunbrella recommend for their canvas is 'Fabric Guard 303' it is available from Amazon.
But for covers that are way past their best or of dubious origin Fabsil or the others will do a job though you may have to retreat fairly frequently, probably at least once a year. You can find some reliable advice on this subject on car restoration sites.

Pretty funny, folks calling Sunbrella canvas, not realizing that the correct product is different.

Starbrite Water Repellent Treatment with PTFE has also tested well. Nikwax is good.

The other thing to be mindful of is that many of the solvent-based and silicon-based treatments will mess up the vinyl windows. Test it on a window scrap first. Sometime the effect is slow, a streak forming as the run-off contacts it over months.
 

pcatterall

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The Spanish use stuff called DECO-ELAST on their flat roofs, you can get it in any good ferreteria or paint shop. If you dilute it with water it becomes a milky liquid that can be painted on to canvas which will dry to the original colour but will have more 'body' and will be waterproof. Easy, cheap, local.
I brought a tub home and do my dodgers, stackpack, hatch covers etc. every few years. I also have a suspicion it helps to UV-proof the stitching which is a real bonus in your neck of the woods.(though no longer for me!)

I despaired of locating this sort of stuff in Spain. There is not a chandlers near our marina in Burriana. BUT there is a Big 'Bricollage' DIY sort of place so I wonder ( now I know the name) if they would have that there. I am just stockingup on items to make up a shipment for when we return in the spring.
 

Yngmar

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I've applied Fabsil this summer, and so far it does the job well. It also supposedly offers some UV protection. Best price I could find was just over £20 for the 5 litre can delivered, from this seller - less half the price the chandlery wanted for it.

Preparation was to wash the canvas with a brush and some soapy water, then rinse the soap out thoroughly and let it dry. I then applied Fabsil with a roller and a second coat once it had soaked in. After the Fabsil do not use soap for cleaning! Just water from the spray nozzle gets the birdshit off okay.
 

Billjratt

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Deco elast probably won't be found in a chandlers. Bricollage or fereteria or (in alicante) the paint shop -beside the white paint for the outside walls!
 

Quandary

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Pretty funny, folks calling Sunbrella canvas, not realizing that the correct product is different.

Starbrite Water Repellent Treatment with PTFE has also tested well. Nikwax is good.

The other thing to be mindful of is that many of the solvent-based and silicon-based treatments will mess up the vinyl windows. Test it on a window scrap first. Sometime the effect is slow, a streak forming as the run-off contacts it over months.
 

Quandary

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Pretty funny, folks calling Sunbrella canvas, not realizing that the correct product is different.

? ????? Sunbrella marine fabric is canvas, or at least that is how they define it on their website and perhaps they might know, what did you think it was?
 

pcatterall

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Deco elast probably won't be found in a chandlers. Bricollage or fereteria or (in alicante) the paint shop -beside the white paint for the outside walls!

Thanks all. I will go for billgratt's suggestion so that is less to send out to Spain. I have a long list of requirements to obtain in UK and now I will need another list with the Spanish names for stuff that I can buy there! .... starting with Deco Elast !
 

No Regrets

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I use a big tin of Fabsil and pour it on, sponging it into the fabric.

Reapply a week later, it does the job well, and lasts 6-12 months.

Costs very little as a tin will do a few applications!

Once applies, chuck a glass of water at it and watch it bounce off like magic!
 

kmiles

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I use the gallon size Marine Fabric Waterproofer. It has lasted me three seasons with just a couple of spots needing more rolled on. It doesn't stink like chemicals and my rubber or acrylic parts are holding up no problem. I am just happy this stuff works for more than a few months lol.
 

MonniotC

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The Spanish use stuff called DECO-ELAST on their flat roofs, you can get it in any good ferreteria or paint shop. If you dilute it with water it becomes a milky liquid that can be painted on to canvas which will dry to the original colour but will have more 'body' and will be waterproof. Easy, cheap, local.
I brought a tub home and do my dodgers, stackpack, hatch covers etc. every few years. I also have a suspicion it helps to UV-proof the stitching which is a real bonus in your neck of the woods.(though no longer for me!)

I'm guessing from the spelling that "ferreteria" literally means "ironmongers". But the first thing that jumped into my mind was a shop full of ferrets :ROFLMAO:
 
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