Gelcoat restoration on Mark 1

[Topi]

Has anyone restored Top Hat gelcoat using Hydrochloric Acid ?

Does it work well ?

What dilution ratio ?

Thanks

[storm petrel]

DO you mean clean the gel coat? An acid wash just removes the grime. It will work fairly dilute but a little experiment with about 5% muriatic acid (conc. HCL) in a household spray bottle will show you what you need. The boat yards generally give the topsides an acid wash when they take the boats out. Be carful not to get it on your skin and wash off the hull with water after. I have used a spray bottle and rinsed the hull with sea water after for quite good results above the bootstrap but it will streak the anti foul above the water line.

[Topi]

Thanks for the formula.

Yes, clean the gelcoat as step one, then some polishing with a wax/polymer to protect it afterwards.

I was curious if Top Hats generally had a thick gelcoat or otherwise compared to other makers ?

[storm petrel]

OK try 5% first and increase to 10% if necessary. Oh and don't get it on your metal through hulls. What fun it is bringing an old boat back to life.....

[Phillip]

Topi,

Acid works just fine, but do not do any heavy sanding of the gel coat as Mk 1's have a fairly fine coating.

Also do not use a silicone based polish because if you ever want to paint or do fiberglass repairs.
You will find that the paint will retreat from any silicone left in the gel coat and for the same reason
you will not be able to flare out the edges of any fiberglass repairs.

I'm about to do this as well, so will be interested in how you go.

[Topi]

"Fine gelcoat", OK that answers that question.

I have noted the issues around silicone products. I have not looked for a polish yet, but from what I gather a hard polishing wax with some polymers seems to be the best. Car waxes are not suitable for boats as they are meant to be applied regularily, where as boat waxing is a yearly thing and the waxes are formulated accordingly with higher UV protection. If anyone knows of a good wax, please advise.

[Tales]

Hi Topi,

I have been using this brew. Works a treat on gel coat and stainless steel.

http://www.ronstan.com.au/marine5/produ ... dNo=RF3005

Main ingredient is hydrochloric acid and it's pretty strong.

Cheers,

Tom

[Topi]

Yes, that looks like the stuff but in a Ronstan Bottle.

I will give the Bunnings version a try on a small section and see how it goes.

I thought the topsides were just gelcoat, but they look like painted gelcoat, so I had better test that as well or it might work like paint stripper :0

Thanks