Sand Washing-What is it?

[foxglove]

What is sand washing?

I read on yachtsurvey.com that sand blasting is not recommended. They Quote; "Under no circumstances should you ever sand blast or sand sweep a bottom. Sandblasting shatters the plastic and exposes the fibers far more than they already are. In addition, it craters the gel coat with millions of craters that only worsens the problem when it is sand swept."

My yard suggested ''sand washing'' to remove the paint (and maybe my 15 year old barrier coat too????) Has anyone tried it?

I have some minor blistering(I have read Jeff H posts on the subject)and I am seeking the best approach. But what is sand washing?

Thanks,

Max

[PaulBl]

My guess is they are refering to low pressure sand blasting. The better alternative would be soda blasting. Baking soda is used instead of fine sand. It can in the hands of an expert remove paint a layer at a time (or almost that precise). It''s not as "sharp" as sand.

You really don''t want to open up the deeper layers at all if possible. You''ll need to repair with epoxy those areas that need it.

You''ll want no more than 12% moisture before you barrier coat or you can''t get a warranty (you want one of those as much as anything).

That alone can take a long time unless they use vacuume techniques to remove the moisture. It''s a pretty neat process with plates that can drop the vapor pressure pretty darn low and basically boil the moisture out at a room temperature. Boiling point drops with a decrease in pressure. Low enough and ice evaporates. Water is a strange substance.

[foxglove]

Thank you very much for the information. I have 15 years of bottom paint and now is a good time to remove it. I hope the moisture level drops to acceptable levels by next summer.

Thanks again

Max