what do you think caused this?

[Silver_Surfer]

i wanted to hear what you thought would cause this to happen to a new bottom paint job.
sailboat 1987 Baltic 43
paint Pettit Trinidad SR black
Had a yard in socal do a bottom job in dec. 2019 and i picked it up jan and moved it to a local marina as i was going to take it to ensenada for among other things a teak deck. sailed in mid feb and due to covid mess didn't get hauled out until first week of july. that's when the mgr called me and asked "what color was the bottom job?"
titles of the pictures show stages, how it looked before work, after new paint applied and how it looked when it was hauled out in ensenada.
i just sold my 37 Baltic and i had a new bottom job done just last week after 5yrs in sf bay and it looked almost new, just some bare spots on waterline. This latest job lasted 6mos?
i would like to hear what your thoughts are on this, i have reached out to a petit rep and other yards and have input from them.
thanks
john

[Singularity]

No answer for you, but bump this to the top.


Is the boat now in Ensanada?

[Silver_Surfer]

Ck going this weekend to get a progress report on this and other items

[Capt Clark]

Trapped water trying to get out?

[Silver_Surfer]

i know that it was painted during dec '19 and that was a rainy month, and i thought moisture might be an issue but for the paint not to adhere for the entire hull and rudder, i think its more than that. i did have another yard mgr. look and he stated that the paint looks too uniform, must have been sprayed. from my house painting days, i never owned a sprayer, and rolling did do a better job penetrating cracks and blemishes and spraying relied heavily on proper prep. again, this damage took only 6 months to do.
thanks

[LakeSuperior]

Perhaps the yard used Krylon flat black to increase the profit margin.

[Offshore74]

Wondering if the paint did not adhere to the previous bottom paint, maybe this paint was not compatible with what was on before? Could be a cycle of bad paint over bad paint. Might need a soda blast? Not sure what the yard did previously.

Chris
Baltic 38DP #12

[Shrew]

The green layer underneath is continuing to delaminate in the Ensinada pictures. There doesn't appear to be any delamination in the 'After-Paint (black)' photos. Whether the black failed, the green underneath is continuing to fail.

My guess is the black was sprayed with a thinner in a very, very light coat with possibly ablative paint, which has since worn off (as it is designed to do). However, the green underneath is built-up on a botom that wasn't properly prepared either.

I would have the bottom soda blasted, wiped down to remove dust (as per paint manufacturers instructions), then barrier coated. then re-rolled (again to the manufacturers recommended thickness).

[barnakiel]

If this is damage to the outer coat only, then :


- impurity particles in the coat. Likely from using a contaminated tool in the process, or else wind blowing some () into the can.


Alternative clue - perhaps the paint did not get mixed well enough before application. This gives concentrations (sediment) in some parts, and less of the active (metal) content in other parts. Thus they start to interact in a similar manner that active and passive SS does.


Do not worry. This is 'normal'.


barnakiel

[Scubaseas]

The barnacles and paint on the bottom of the keel are a bit odd. Was it bottom paint they applied? Did it get pressure washed before the second set of pictures? Maybe one really thin coat of bottom paint with little prep work and one overzealous power washing?

[Silver_Surfer]

Originally Posted by Singularity

No answer for you, but bump this to the top.


Is the boat now in Ensanada?

Yes she is. Going this weekend to check on progress and get a better paint sample for petit

[Silver_Surfer]

i have video of initial haul out, and you can see a layer of black algae but poking out see splotchs of green. this wasn't done by a over zealous power washer, i just had my 37 baltic done at sf boatworks and you can't blast this paint off, its a hard paint. this is my bottom after 5yrs, hardly needed a new paint job, just did it since selling and new owner wanted it done.

[Silver_Surfer]

like i mentioned, i do believe this isn't a paint issue, but a prep issue. so yes, your ideas i think ring truer than what the yard is claiming.

[Silver_Surfer]

thanks for the input so far, now if you could think this through. knowing the time frame, 6 months from new bottom paint in dec/jan 2020 to july 6th 2020 the entire paint job is gone for the most part.
The explanation by the responsible people for this job, that this is casued by a "hot marina" basically saying its electrolysis that removed a perfectly well prepped bottom and paint job.
i know that "stray voltage" electrolysis on a boat or structure can do damage to paint and un-bonded metals, but it will leave a signature in a corona ring around a brass thru hull, which this boat has blakes thru hulls. since metals will attract and concentrate at metal items like props, anodes, etc.
this is has not been observed and i have not seen any example of electrolysis as described in this article in Sea Magazine " If you see large ugly burn patterns around all your metal through-hulls — haloing — you have a stray current problem."
again, i'm going down this weekend to ck boat out, but i had yard mgr. ck for Haloing around thru hulls or any metal objects, and there wasn't any.
thanks again for the input.

[Bluejacket]

I didn't read all the replies so this may be a repeat of a previous posting.
This has all the looks of out gassing form blisters. Not all blisters are visible on the surface. I've aggressively sandblasted what I thought was a solid hull only to find a 1,000 pencil size holes afterwards.
If you can still access the hull find a spot and dig into the glass. If it smells like vinegar, you have blisters