Mold/Mould on Canvas

What is best to remove it?
After a month of rain almost daily rain, there is mould aplenty, not just on canvas. I`d use bleach but I like my blue canvas blue.
Word at the marina is vinegar. And that bleach just removes the color from mould but does not kill it, I think that`s BS. I`m trying vinegar at home but not impressed so far.
Any bright ideas on what kills mould without bleaching the canvas? I once used oil of cloves added to baby oil to clean "mildew" off a leather jacket, worked well, but I might need a lot of oil of cloves to do the canvas.

I like Starbrite Mildew Stain Remover. Have used it on several items and it worked well. Sometimes need to apply it twice and let it soak for a bit.

Comodave said:

I like Starbrite Mildew Stain Remover..

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Thought of that but instructions say not to use it on fabric. Did you find it ok in practice?

303 Fabric and Vinyl Cleaner finished off with 303 High Tech Fabric Guard

Pure bleach will not kill mold - puts into shock and the mold cells will not take any liquids across the membrane, thus bleach having no effect. A solution of 80% water and 20% bleach is mild enough to cross the mold's membrane and will kill the mold cells - and should not discolor the blue fabric. Try it on an inconspicuous spot.

Cayenne Pepper ?

You probably need a two step process. Use vinegar to kill the mould. Do a couple of applications. Then after a few days wash the canvas. Maybe try with a pressure washer on the fan/low pressure setting?

Bruce
I posted a summary of Care & Cleaning of Sunbrella in the TF Library - Misc section.

This is a summary of info available from Sunbrella, 303 and my personal experience.

Sunbrella stands up to bleach solution quite well and is part of their recommended cleaning. I've found it best, if possible, to remove the "canvas" and soak it in the solution (bathtub works well) vs simply wiping / spraying it. Just be sure to rinse several times and retreat w/ water repellent.

Vinegar has been reported to be an effective mold preventive - may be helpful to use it periodically to prevent return of the mold. I've done this on the inside of a camper back and it seemed to help reduce return of mold. Bottom line the best prevention is to eliminate any moisture that enters a closed area and provide fresh air circulation... I realize that's a challenge in rainy periods.

Does Vinegar Kill Mold

Lastly - I've used Wet & Forget outside around the house and had good results - never used it inside or on Sunbrella - but might be worth a trial on a small section?

I used to use chlorine from the pool store to spray my house's north wall once a couple of years or so. No mold can survive that stuff.

Ive used 50/50 vinegar and water. May need a few applications in heavy area's. Then Powerwash and repeat if needed. Once its clean and dry Put the 3m 303 on to help preserve and protect. If you get yourself a 1 gal pump sprayer with the wand it makes the job a lot easier than a spray bottle.
As Don stated above, the sunbrella website has a lot of good info.

This weekend it wasn't raining, much anyway. AT the marina everyone came out of their winter holes and started to clean the green off their decks and canvas. I commented to my wife that the best solution would be to just get green canvas when we finally break down and replace ours.

Thanks for all the ideas,looks like there are several ways to approach it. Even camouflage.
I applied vinegar last Sunday during a break in the rain which will have rinsed the canvas many times by now,I`ll check it next weekend.

I have used the Starbrite MSR on canvas many times with good results. I would try it on a small area first and see how it works for you.

Sometimes stubborn black spots don't respond well to bleach. I tried a suggestion to use non-copper pool algaecide. I mixed it about 2 Oz. to a gallon of water in a garden sprayer and applied it to my Sunbrella and vinyl on a weekly basis. After a month, most of the spots were gone. They had resisted all kinds of cleaners and bleach. I found the spray irritating, so I put on my respirator. Probably the standard 3M paper mask would be fine.

Practical Sailor mag. has also run some articles about mildew/mold.
I use borax after a bleach application. The bleach to kill it and then the borax as it is absorbed and m/m do not like it.

Then the 303 as a water repellent.

I too use a 1 gallon garden sprayer to apply the 303. Much better and doesn't tire out your hand

From Sunbrella:


Heavy Cleaning For Stubborn Stains And Mildew

Sunbrella fabrics do not promote mildew growth, however, mildew may grow on dirt and other foreign substances that are not removed from the fabric. To clean stubborn stains:

• Prepare a solution of 1 cup of bleach and one fourth cup mild soap per gallon of clean water.
• Allow mixture to soak into fabric for up to 15 minutes.
• Blot stain with a sponge or clean towel. Note: This step should be avoided when cleaning the coated side (Back side) of Sunbrella Plus, Supreme, or Clarity.
• Rinse thoroughly until all soap residue is removed.
• Air dry.

Note: Use caution when cleaning the coated (underside) of Sunbrella Plus, Supreme, or Clarity with the recommended bleach solution. The coated side of the fabric should only be sprayed with the recommended bleach solution and rinsed thoroughly.
Remember to protect the area around your Sunbrella if using a bleach solution. Carpet or other fabrics that are not Sunbrella may have an adverse reaction to the bleach.

We have had a very wet winter and mold on the underside of my canvas top has been a challenge. I have been waiting for a few clear days in which I can take it down and clean it and reapply 303.

In the mean time I have used this on the underside. I apply it to a sponge mop and apply it. After a few hours the mold is gone. Last about a month or so, then I have to reapply. I bought it at Tractor Supply Company.

Never had this problem in the past, but we have had a very very wet winter. Still raining. This time last year we were in the upper 70s! This year we can't even get into the 60s.

I feel for you ASD, we`ve had about 5 weeks of mostly rain, not good for boating or for canvas.
How do you tell which side of Sunbrella is the coated side? Does the coated side stay coated after several years of weather exposure?

BruceK said:

I feel for you ASD, we`ve had about 5 weeks of mostly rain, not good for boating or for canvas.
How do you tell which side of Sunbrella is the coated side? Does the coated side stay coated after several years of weather exposure?

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That part is the underside of the canvas. When we bought ASD it had the supreme with a rubber type coating on the underside, but does not breath very well. It was 20 years old, so it did last in that CA heat.....

Works ok

BruceK said:

Thought of that but instructions say not to use it on fabric. Did you find it ok in practice?

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This works well on sunbrella.

Over the past few years, I have seen the return of mold/mildew to the underside of the upper fly-bridge bimini top. In the past, I have just used soap and water to wash, but the mold/mildew keeps returning. I've resorted to trying the following in this order:
1: Vinegar
2: 303 Mold and Mildew Remover (Cleaner + Blocker): https://amzn.to/2FW131w (Okay on fabric, vinyl, & fiberglass)
3: Concrobium, Mold Control: https://amzn.to/2ScWAgw (Okay on fabric)
4: Starbrite Mildew Stain Remover: https://amzn.to/2SfxsWm (contains bleach, instructions say NOT to use on "fabric" (AKA: Canvas)

Go to Practical Sailor for their homebrew. I used it on my Ranger truck when it got a bad dose 2 yrs ago. NO more since.

https://www.practical-sailor.com/bl...ailor:e37639:106682a:&st=email&s=p_Blog051018

Tried vinegar, resorted to pressure washer. Can be tough on stitching unless very careful, but mine needed resewing anyway. In fact, if you`re up for resewing, it`s a good way of removing/loosening the stitching.
Resewing is a good way of extending the life of canvas. Mildew is not.

I use white vinegar and water (about half half) and mix in some tea tree essential oil, lavender oil and eucalyptus oils. For a quart of liquid- about 10 drops of each. I spray it on the spots then s rub with a cloth. Had toned down the molds on my Bimini. I also try to get good airflow as much as possible as well.

C lectric said:

Go to Practical Sailor for their homebrew. I used it on my Ranger truck when it got a bad dose 2 yrs ago. NO more since.

https://www.practical-sailor.com/bl...ailor:e37639:106682a:&st=email&s=p_Blog051018

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Double thumbs up on this one. Thanks.