What to coat the boat bottom for speed?

[RichH]

The bottom of my boat appears clean. You can see in the 2 attached pictures. The white part of the hull is very smooth. The light blue looks clean but it is actually a little rough to touch. Also when I touch the blue it likes to rub off onto my hands a little.

So should i wet sand the light blue paint of the hull or leave it? Does it rubbing off on my hands mean it needs to be repainted or is the wet sanding all it needs?

Thanks Mike

For the most efficient results, and since your hull seems quite clean ... Id suggest that you lightly wet sand down ('just') the 'proud' paint pimples, dribs and roller marks and roller 'stipple'. Do this NOT into the paint proper but just the 'hills', forget the 'valleys' and the already FLAT surfaces in between. Flatness, especially at and near the leading edge is what will lessen hull friction by keeping the water flow across those leading edge areas 'non-turbulent'. Its the pimples, dribs and roller marks that are sticking-up will be the main cause of losing 'laminar flow' on the hull; again mostly affecting the front-most surfaces. Do the rest of the surfaces such as the trailing edges when you have plenty of time such as when putting on new bottom paint (but dont use a paint roller to apply the new paint so to keep the 'stipple' and roller dribs to a minimum). 320 grit W&D will probably give you the fastest method for getting rid of the errant paint and roller errors.

 

[Jackdaw]

For the most efficient results, and since your hull seems quite clean ... Id suggest that you lightly wet sand down ('just') the 'proud' paint pimples, dribs and roller marks and roller 'stipple'. Do this NOT into the paint proper but just the 'hills', forget the 'valleys' and the already FLAT surfaces in between. Flatness, especially at and near the leading edge is what will lessen hull friction by keeping the water flow across those leading edge areas 'non-turbulent'. Its the pimples, dribs and roller marks that are sticking-up will be the main cause of losing 'laminar flow' on the hull; again mostly affecting the front-most surfaces. Do the rest of the surfaces such as the trailing edges when you have plenty of time such as when putting on new bottom paint (but dont use a paint roller to apply the new paint so to keep the 'stipple' and roller dribs to a minimum). 320 grit W&D will probably give you the fastest method for getting rid of the errant paint and roller errors.

What rich said. For clarity, focus on your hull forward of the middle of your aftmost window. Aft of this point, the hull curves in and back to the transom, and the laminar flow will detach anyway.

 

[McIntoshUSA]

What rich said. For clarity, focus on your hull forward of the middle of your aftmost window. Aft of this point, the hull curves in and back to the transom, and the laminar flow will detach anyway.

Thank you for your suggestion on sanding the areas. I quill give it a try next week.

 

[McIntoshUSA]

For the most efficient results, and since your hull seems quite clean ... Id suggest that you lightly wet sand down ('just') the 'proud' paint pimples, dribs and roller marks and roller 'stipple'. Do this NOT into the paint proper but just the 'hills', forget the 'valleys' and the already FLAT surfaces in between. Flatness, especially at and near the leading edge is what will lessen hull friction by keeping the water flow across those leading edge areas 'non-turbulent'. Its the pimples, dribs and roller marks that are sticking-up will be the main cause of losing 'laminar flow' on the hull; again mostly affecting the front-most surfaces. Do the rest of the surfaces such as the trailing edges when you have plenty of time such as when putting on new bottom paint (but dont use a paint roller to apply the new paint so to keep the 'stipple' and roller dribs to a minimum). 320 grit W&D will probably give you the fastest method for getting rid of the errant paint and roller errors.

Thank you for your suggestion to sand the hull and what to use. I plan to try it next week
Thank you