12 replies to this topic

[bentg]

Hey, Jeff, I read that you were going to paint the re-skinned Sling Shot with latex.  How did it work out?  Did you get good abrasion resistance?

[Kudzu]

I did, you can see photos in 'Long Shot * The sequel' thread.

I have mixed feelings, it looks good and I think it is a good coating especially for someone with medical issues or just doesn't want the VOC issue with oil based paints. But bottom line is an oil based finish is definitely tougher.

Latex takes a long time to cure. Mine is 2-3 months old but  it still marks fairly easy. It appears the first coat is really well bonded to the fabric, then the second and third coats just don't seem to adhere as well to the base coat. They will scratch pretty easy but it seems to leave the base coat intact.  I assume that the second coats have a mechanical bond instead of a chemical bond to the previous coat.

I have a big spot on the side of where it rubbed on trailer that I need to touch up. I have heard that touch ups are easy and they blend really well but I just haven't gotten around to it. If that is the case then that would improve my impressions of it. Because frankly I love the water clean up and the way it looks on the boat. It's a little  harder to apply than enamel. Seems not to spread as easy and took me at least 3 coats. I could shine a light through and see pin holes. But I think thinning it would probably help that too.

I will probably stick with oil based for now and just use disposable brushes so I don't have to clean them up.

[bentg]

I'm trying your Rustoleum oil technique as soon as I can get the shop above 50 degrees, mainly because my impressions agree with yours about the latex.  It just scratches too easily.  I made a pirogue a number of years ago and covered it with latex (this was MDO plywood, not a skin boat.)  Even after it cured--which took more than a month--it still gouged and scratched.  Not such a big deal for my own boat, because it is easily fixed, but I wouldn't feel good selling a boat new to someone and having to say, "It will scratch a lot, so just touch it up with this can of paint."  I had hoped latex had gotten better in the last ten years, but I guess abrasion resistance is not a priority for the latex paint formulation.

[Hirilonde]

Is it that you really wish latex paints would work well?  Or that a good abrasion resistant water based paint exists, whether latex or not?

[Kudzu]

Is it that you really wish latex paints would work well?  Or that a good abrasion resistant water based paint exists, whether latex or not?

YES!  :wink:

[Hirilonde]

Is it that you really wish latex paints would work well?  Or that a good abrasion resistant water based paint exists, whether latex or not?

YES!  :wink:

I'm guessing that your are the guy who walks into Baskin and Robbins and asks for an ice cream cone and expects the counter person to know what you want. 

What I am getting at is that there are other water based paints besides latex.  System Three is one.  I don't know what prep or primer would be needed to adhere to polyester cloth.  But I would bet you could contact them for technical info.

[Kudzu]

The durability is what is important to me.  Water based would be great, no fumes and easy clean up.  But durable trumps most everything else.

Latex is just a commonly used term for water based finishes even if it isn't totally accurate.

[bentg]

Hirilonde, that System Three poly looks great.  Have you used it before, and what were the results?

[ChrisObee]

System three paints set up as hard as a rock.  I suspect that the system three primer would stick to nearly anything.  My only question would be the flexible nature of the skin.  the system three might crack when set on a flexible surface.  I've only applied it to plywood.

[Hirilonde]

My only question would be the flexible nature of the skin.  the system three might crack when set on a flexible surface.  I've only applied it to plywood.

That is certainly something to ponder.  I have never tried to maintain a flexible shell like on a SoF hull. 

I have used Awlgrip's interior water based LPU, but not System Three.  The main difference I can see between water borne and chemical is the shine.  Reports over the past year or so on Sytem Three are very good if you can live with a semi-gloss, or at least a less shiny gloss. (where the line between the 2 is is rather subjective)  I would start by asking their tech support about applications and suitability.  If it can stand up to the flexible skin I would certainly try it.  As Chris has stated, it is very hard.  If the craft were going to be somewhat abused then a less than glossy finish would actually be desirable.

[Kudzu]

Very interesting reading since I was not familiar with either of these.

BTW, semi-gloss is a better choice for SOF unless you are a really good painter. Because of the texture of the fabric anywhere you have the paint a little thicker will be glossier than the thinner areas and it really stands out.  I find it hard to get a perfectly even coat so I like the semi gloss and I like the way it looks much better.

[Hirilonde]

Latex is just a commonly used term for water based finishes even if it isn't totally accurate.

BTW, I have never heard of using latex to mean any water borne paint.  But if this is true, then it is a very dangerous generalization to use in a technical forum.  Water borne paints use water as the primary vehicle.  Latex is not a vehicle, but another component of some paints.  I am not a chemist, and will not pretend to be an expert on the chemistry of paints.  But if we are going to compare paints in our discussions we should make a point of accurately describing them.

There are many misused generalizations.  They might seem meaningful to some, but are a distraction from accuracy to others.  They often lead to misunderstanding by many.

[PAR]

Latex is just a commonly used term for water based finishes even if it isn't totally accurate.

More accurately the latex is describing acrylic type paints. If the term was describing water borne coatings, then several other types of paints, including some polyurethanes and epoxies would be mis-labeled. In the USA, latex was part of a popular brand name for some years, when acrylics first gained acceptance. The net result is that this type of paint developed the name, incorrectly, much like Kleenex for tissue paper or "take an aspirin" when they know it's really an ibuprofen tablet.