Oxalic acid working temperature

Fr J Hackett

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Thank you for that, makes sense.

I've been told that a layer of oxidation builds up on the gelcoat and this needs to be stripped back by a "mopping' process to reveal fresh getcoat and this can only be done so many times. I'm hoing this is not the case with my boat.

As said above, the oxalic acid treatment worked really well on my hull, problem was the staining came back almost immediately after its re launch.

I am hope I was incorrect in re-polishing the hull, when I should have sealled it with a wax product.

I shall wait until the spring and redo the OA treatment followed by plenty of wax.

Boat is a 7m Rib that is in excellent condition other than its "dirty" looking bottom, lives in a rack during the summer, barn in the winter.
Gelcoat is to a degree porous and the stains become embedded in it the only answer I found was to apply a wax coating each year which kept the hull reasonably clean and looking OK. I periodically and very lightly used a very fine abrasive used to polish cars prior to applying the protective coating which will deteriorate. I used oxalic acid locally to remove any staining prior to both the above treatments. It worked for me.
 

Refueler

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Far away from hooray henrys
Thank you for that, makes sense.

I've been told that a layer of oxidation builds up on the gelcoat and this needs to be stripped back by a "mopping' process to reveal fresh getcoat and this can only be done so many times. I'm hoing this is not the case with my boat.

As said above, the oxalic acid treatment worked really well on my hull, problem was the staining came back almost immediately after its re launch.

I am hope I was incorrect in re-polishing the hull, when I should have sealled it with a wax product.

I shall wait until the spring and redo the OA treatment followed by plenty of wax.

Boat is a 7m Rib that is in excellent condition other than its "dirty" looking bottom, lives in a rack during the summer, barn in the winter.

Think of Gelcoat like a paint layer ... you can only remove poor surface so many times before you start to see thin areas and the underlying showing through.
But unlike paint - Gelcoat is much thicker and can withstand this for years ... lets say you Oxalic at start of season - then use handy house cleaners later in year ... basically OA once per year .... and then just general washdowns after that ...

Polish ... depends on the polish used .... some are abrasive to remove that dull surface ... while others are really a synthetic based wax substitute ... with cleaners mixed in.

My preferred household cleaner for general mild stuff - is 'Toilet Cleaner' ... such as Harpic and other brands ... the best WAS Cilit Bang Lime and Rust - until EU got its knickers in a twist and forced its change of formula ... now its no better than any rivals.
 
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