waterproofing bimini

[edithcollins]

So the bimini now leaks under a heavyish rain.  It seems that the fabric becomes saturated easily.  The dodger and fly are fine.
I have seen many opinions of what works for waterproofing.
What have YOU used that works?
Thanks!
Edith

[Captain Bri]

I don't have the luxury of any canvas on my boat but I have done a lot of repair work as a part time sailmaker.  It really depends on the material - most bimini's are probably Sunbrella, an acrylic which may begin leaking after a few years when its factory treatment wears out.  Assuming your are using an acrylic you can approach it with the methods used for treating canvas - except that you need to avoid silicone.

I like the advice of Dan Casey found on boatus.com at:  Waterproofing Canvas

In a nutshell it says:
- choose the right treatment based on material
- clean the cloth thoroughly
- apply treatment and re-apply as necessary

Here is the recommended treatment from Glen Raven, the manufacturer of Sunbrella:

Re-treating the Fabric - As part of the finishing process, Sunbrella® fabrics are treated with a fluorocarbon finish, which enhances water repellency. This finish is designed to last for several years, but must be replenished after a thorough cleaning. Based on test results, Glen Raven recommends 303 High Tech Fabric Guard™ as the preferred re-treatment product for Sunbrella® fabrics.

Fabrics should be retreated after thorough cleaning or after five years of use.

Application: 303 should be applied to Sunbrella® fabrics after each thorough cleaning, which typically removes the original fluorocarbon finish and reduces the fabric's water resistance. After cleaning the fabric, allow it to air dry completely and then apply 303 in a thin, even coat. After allowing the first coat of 303 to air dry, apply a second thin, even coating of 303. Two light coatings are more effective in restoring fabric water resistance than a single coating.

[edithcollins]

Thanks Brian!

[Bill1188]

Rustoleum makes a product, Never Wet, which is more or less 303 Protectant at a fraction of the price. Non silicone, compatible with Sunbrella. Got mine at Home Depot.

[Dolce_Vita]

I have used ScotchGuard Fabric protector spray with success, but it's expensive and only lasts for one season.  I paid around $12 per spraycan, and it took 4 cans.  Still, with a quote of $800 for new bimini canvas, I'm going to get as much life out of this one as I can!

The Neverwet is an interesting idea, but be warned that it is not clear.  It ends up as a frosty translucent white.

[edithcollins]

I ended up using the 3M product.  It was very easy to apply and seems to have done the job.  Thanks for your advice!
Edith

[Frayed Knot]

A little late but the 303 is the best $$$

[Last Resort]

sorry to disagree with others, but there is NOTHING better than Aqua-tite!!! My canvas guy put me onto it years ago, and even with my 15 year old canvas, no leaks again this year, especially since someone else taught me to brush it on and not just spray it on. I redo it every spring to start the season. It is expensive, but well worth it if you want to stay dry.

[Dolce_Vita]

sorry to disagree with others, but there is NOTHING better than Aqua-guard!!! My canvas guy put me onto it years ago, and even with my 15 year old canvas, no leaks again this year, especially since someone else taught me to brush it on and not just spray it on. I redo it every spring to start the season. It is expensive, but well worth it if you want to stay dry.

Tried looking up Aqua-guard, but only came up with an elastomeric pool paint, and a bunch of waterproofing companies.
Could you supply a little more brand detail, or a link?  Thanks!

[Last Resort]

Sorry, got my paint and sealant mixed up, and my buffing compound is Aqua Buff, so no wonder  

I made the correction in my original post. GREAT STUFF!!!!

[Captain Bri]

sorry to disagree with others, but there is NOTHING better than Aqua-tite!!! My canvas guy put me onto it years ago, and even with my 15 year old canvas, no leaks again this year, especially since someone else taught me to brush it on and not just spray it on. I redo it every spring to start the season. It is expensive, but well worth it if you want to stay dry.

Sailrite also recommends the Aqua-Tite Water Repellent product for material that is 5 years or older - and they are usually a pretty good reference.  They did a video demo: https://www.youtube.com/watch?v=bE5c187cUPU

Detailed Description from Ebay:
This is the new "Green" formula from Aqua-Tite.  This 1 quart bottle will cover a 20' or so cover once.  They say it will cover between 125 and 175 square feet.  This is to be used on Acrylic, cotton, nylon, polyester, polypropylene, and cotton/poly blends.  Water drops will bead and roll off.  It provides outstanding protection against aqueous based stains such as soda and juice.  Resists dirt and oil-based stains such as animal dropping, motor oil, and lubricants.  It has very good durability to outdoor weathering.  Enhances the tone of treated fabric.  This will come with a spray nozzle.