Is caustic soda safe on GRP?

[BoatingBeginner]

I've got some antifoul to strip. I want to go down the caustic soda / wallpaper paste route.

Will it damage the underlying GRP? The paint has come away in pieces where it wasn't properly prepped in the past - only here and there, alas - so there's exposed fibreglass already, and I don't want to damage this.

Should I wash with a vinegar solution afterwards?

Thanks, folks.

 

[VicS]

No problem with what you are doing. GRP is adequately resistant to caustic soda.

gather up all waste and dispose of safely.

Wash well with water. Id not bother trying to neutralise it with vinegar.

Full protective clothing. wash any splashes off the skin immediately and neutralise with vingear or dilute citric acid if you like.

DO NOT under any circumstances get any in your eyes. You wont be able to wash it out yourself, it'll be excruciatingly painful and permanent damage is very likely. It would be wise to have the where-with-all available for someone to irrigate your eyes if necessary.

 

[BoatingBeginner]

Thanks very much for that.

I've got the goggles and gloves standing by!

 

[Euphonyx]

DO NOT under any circumstances get any in your eyes. You wont be able to wash it out yourself, it'll be excruciatingly painful and permanent damage is very likely. It would be wise to have the where-with-all available for someone to irrigate your eyes if necessary.[/QUOTE]

yikes!!

 

[VicS]

yikes!!

Yikes indeed .
Natural reflexes prevent you from opening your eyes ... So somebody has to do it for you.

More dangerous that strong acids of similar concentrations because the caustic soda attacks the materials ( proteins) of which the eyeball is made . Damage is permanent and if that happens to be on the front of the eyeball its going to affect your sight permanently.

Safety helmet with full face shield attached is really preferable to goggles.

Long gloves preferred to ordinary safety work gloves.

Impervious apron and welly boots.

BTW a lot of heat is generated when NaOH is dissolved in water. You can end up with it near to boiling and it produces choking fumes! Make sure the mixing vessel will withstand the temperature. Polythene may not. It'll dissolve galvanising and aluminium so neither of these are suitable.
You also need to keep it stirred while its dissolving or you end up with a solid mass sitting on the bottom that then takes forever to dissolve.

It is not nice stuff if you handle it wrongly.

 

[rivonia]

There must be a better way as this all sounds VERY dangerous!

Peter

 

[Jim@sea]

Be careful if your boat is sitting on a galvanised trailer as caustic soda can also strip the galvanising off.

 

[30boat]

Be careful if your boat is sitting on a galvanised trailer as caustic soda can also strip the galvanising off.

Or paint.The yard won't be too happy.

 

[VicS]

There must be a better way as this all sounds VERY dangerous!

There is. It is called soda blasting. It uses bicarbonate of soda.

 

[oldharry]

This sounds altogether like one of those 'good ideas'.

There are much safer ways of saving time and money!