I have purchased a 20 year old wood sailing skiff that was built with cedar lapstrake planks. The inside was finished with linseed/terp/varnish mix and now has mildue on it. 3M 5200 was used in the lap seams. Some chemicals can disolve 5200. I emailed 3M asking what to use and they emailed back “I am not aware of a cleaner that can be used to remove mildue but not also have an effect on 5200. We have done no testing for this application so I can’t make any recommendations. I would suggest contacting some of the companies that manufacture mildue cleaners for wood and see if they have any ideas. You can ask them if their cleaners have any detrimental effects on mosture cured urethanes, which is what 5200 is.” This is legalistic bullshit or irresponsibility since 5200 is sold as a marine adhesive and mildue is common in water uses. They are dumping all responsibility onto me to find a safe cleaner.
Anyone have any suggestions?
Bleach
Wha Ho, Pilgrim;
Try some watered down bleach in a small inconspicuous area above the waterline and see if the mildew comes off and the glue doesn’t. Worth a try.
Fat Elmo
Do a google on "tent stink"
There is a two-step remedy to killing mildew that involves soaking in mixtures of salt, lemon juice, Lysol, and hot water (not all together at once!), and drying fully in between the soaking steps.
I doubt any of these agents will hurt your boat’s materials, so it won’t hurt to try it.
3M response
Read the warranty statement on a pack of 3M Scotch tape. They accept no responsibility for anything, no how, no way. It’s the company line.
Try TSP
Trisodium Phosphate. It can be found at most hardware stores. It kills mildew, and is very mild. Make sure that you use gloves because it will dry out your hands (it is a good degreaser).
Hope this helps,
-MEAT