Paint thinner for bottom painting

[larman]

I am in the process of prepping my boat bottom for painting. I need to wipe the entire surface with a paint thinner, can any thinner be used? The manufacturer recommends Petitt 120 thinner but its expensive. Also any idea how much I would need to wipe a 41' down?

 

[Pete Meisinger]

I have used mineral spirits with acceptable results but someone once told me that mineral spirits leave some type of oil residue. I guess this makes sense but my thinking was that if I am using oil based paint why would this be a bad thing (if it is true).

Can't you read the label of the Petitt and try to duplicate that. It may be closer to acetone than mineral spirits.

pete

 

[rslifkin]

If it's just to wipe down for cleaning, I'd expect any thinner that dries without residue should do the job.

 

[larman]

Thank you!

 

[kchace]

I am in the process of prepping my boat bottom for painting. I need to wipe the entire surface with a paint thinner, can any thinner be used? The manufacturer recommends Petitt 120 thinner but its expensive. Also any idea how much I would need to wipe a 41' down?

After all the work and expense to get the bottom painted, I wouldn't mess around. I would use exactly what the manufacturer recommends. A quart of thinner should do it.


One possibility to save money, see if you can get a copy of the MSDS and find out the main ingredient then see if you can buy that in a paint store.



Ken

 

[psneeld]

What was on there before?

After sanding or pressure washing an ablative..and no cotamination.....

I have never.wiped a bottom down except with a dry cloth after heavy sanding .

 

[larman]

Ablative paint as per previous owner. It looks like it has not been painted in a while.

 

[psneeld]

Wiping with proper thinner can't hurt I would guess....just in the future ....depending on your choices and system it may be overkill.

 

[larman]

I have removed all the barnacle remains from the bottom of the boat and roughed up the bottom with a 3m scotch-brite pad. I then washed the bottom. When it dried I ran my hands along it and I am still get powdered ablative paint to come off. Should I pressure was the bottom to remove the remaining powder? I'm thinking that it is an ablative paint and it should be coming off when I rub it?

 

[kchace]

Yes. Ablative paint should always come off when you rub it.

 

[Comodave]

If you are going back with an ablative paint, just power washing is all that is usually required.

 

[SoWhat]

I have removed all the barnacle remains from the bottom of the boat and roughed up the bottom with a 3m scotch-brite pad. I then washed the bottom. When it dried I ran my hands along it and I am still get powdered ablative paint to come off. Should I pressure was the bottom to remove the remaining powder? I'm thinking that it is an ablative paint and it should be coming off when I rub it?

You just need a clean surface. If you are working on bare fiberglass, then a toluene wipe is necessary. If covering a previous layer, then pressure wash after roughing should be good enough.

Mfg thinners are very costly and I use them strictly for thinning.

 

[jleonard]

I have always done a "quick" wiping off with acetone on a damp rag to remove dust.
I emphasize "damp" meaning just enough acetone to collect the dust.

 

[bayview]

No dont use any oil (mineral spirits) or turpentine type based thinner. Always use proper thinner or you may create serious adhesion problems

 

[FF]

"After sanding or pressure washing an ablative..and no contamination.....

I have never.wiped a bottom down except with a dry cloth after heavy sanding ."


Makes sense the paint you are washing off is still good , many layers protect better than a thin coat.

 

[Ski in NC]

I use ablative and even after a wipe down, once old paint truly dries, if you wipe with a hand or cloth, you will get residue. That's just the paint doing its thing. I don't worry about it, I don't try to get it off.

I tend to thin the paint and go on with multiple thin coats with a brush. This tends to get a much slicker surface than going on thick with a roller. Takes a lot more time though. I do use the recommended thinner, it is printed on the paint can. Since my boat cruises at planing speed, I think the smooth bottom helps more than it would if all I ran was hull speed.

This is Micron CSC, used since I built the boat.