Hypalon and Acetone

[Avionics_Joe]

If it were my dingy I would just make chaps for it.

[JPA Cate]

Originally Posted by Avionics_Joe

If it were my dingy I would just make chaps for it.

That certainly is a way to get it looking better. The real problem is that djousset's dinghy is a rescue dinghy, and it is probably pvc. With pvc dinghies, once the plasticizer starts to come out, they don't have a long working life. I personally would not make a 15yr. set of chaps for a finished pvc dinghy.

It is the history of this particular dinghy that makes chaps an unattractive idea for me: it's unknown origin, the great likelihood that it is pvc; and the fact that when the plasticizer starts coming out, it's really on its last legs. I have sewn two sets of chaps for our current pvc dinghy.

Ann

[thinwater]

Originally Posted by djousset

My Mercury Hypalon RIB was previously painted with Petit inflatable boat paint. The tubes became sticky mid/end of last season and attracted a fair amount of dirt. Stickiness is mostly gone while stored inside over the winter but the surface looks awful.

Was the stickiness likely due to improper painting technique?
Can I use acetone to clean it, and best practices to repaint?

Thx,D

I can't see where Pettit makes paint for inflatables (other than antifouling). What product?


I painted a Hypalon tender with MDR paint. It was good for ~ 7 years. Then I repainted. Like a very flexible house paint. Also works on sails without peeling.

[GordMay]

Originally Posted by thinwater

I can't see where Pettit makes paint for inflatables (other than antifouling). What product?

I painted a Hypalon tender with MDR paint. It was good for ~ 7 years. Then I repainted. Like a very flexible house paint. Also works on sails without peeling.

According to the manufacturer, Marine Design Research’s [MDR] ‘Inflatable Boat Top Coat’ can be used on Hypalon, PVC, or rubber inflatables.

See also: MDR’s ‘Amazon’, Synergy Research Corp’s ‘Tuff Coat’, Polymarine’s ‘Flexithane’ [Hypalon[ & ‘Superflex’ [PVC], and Flexabar Buoy Coating’s ‘Flexdel’, as reviewed [below].

“A Peek at Inflatable-dinghy Paint Test Panels After One Year” ~ Practical Sailor, Updated: March 2, 2020
➥ https://www.practical-sailor.com/boa...after-one-year

[djousset]

Thanks all, I've learned some things here. My dinghy is PVC, and I wasn't aware of the plasticizing process.

@thinwater
It was MDR top coat not Petit, my error. It only got sticky after the paint job, which made me think the paint job was the culprit. Do I want a nice looking dinghy? Yes. But I'd be happy with a dirty looking, non-sticky dinghy. My goal is to not have the sticky return.

I'll give it a good scrub with mild detergents and, as Wotname suggested move up if needed to slightly stronger stuff. Then a protector or maybe a new top coat of MDR paying close attention to the application directions. What could possibly go wrong..?

[thinwater]

Originally Posted by djousset

Thanks all, I've learned some things here. My dinghy is PVC, and I wasn't aware of the plasticizing process.

@thinwater
It was MDR top coat not Petit, my error. It only got sticky after the paint job, which made me think the paint job was the culprit. Do I want a nice looking dinghy? Yes. But I'd be happy with a dirty looking, non-sticky dinghy. My goal is to not have the sticky return.

I'll give it a good scrub with mild detergents and, as Wotname suggested move up if needed to slightly stronger stuff. Then a protector or maybe a new top coat of MDR paying close attention to the application directions. What could possibly go wrong..?

My guess is that the dinghy was already sticky when they painted it, hoping the paint would cover it, and the sticky ruined the paint job. Not very surprising. I know amine blush on epoxy will do that. The paint just stays sticky. Same with any wax under varnish.



If the sticky were removed before the paint was applied, would it prevent the return? I'm not sure. Sealing the surface (paint will do that, protectors won't, and they will make if impossible to paint later) may slow the process significantly, but I have no direct experience. Articles suggest it will help. Painting with MRD is very easy. Give it a super-scrub and slap on some paint.



I'm guessing a "protector" is a complete waste of time. Interestingly, if you search for 3rd party testing of protectors for anything other than shine and water beading you will find nothing. Nadda. And the makers publish nothing. The answer, most likely, is that the product do much less productive than they want to claim. Not a good story to tell.


BTW, pick the lightest gray. Darker colors heat the tubes and the pressure goes all over the place.

[JPA Cate]

Agree about the lightest gray. I don't know if thinwater noticed the paint job they had on the dinghy, so for any who have forgotten, it was bright red and cream, really spiffy looking.

At the end of the day, if the light gray paint will do it, that's way better than having to dumpster the dinghy, even if no longer quite so spiffy.

Ann

Ann

[djousset]

@thinwater and @JPACate, thanks for the additional tips on protectant, MDR and color choice.
@AvionicsJoe, I'm not opposed to sewing a set of chaps as life support if I can get it to a reasonable condition.

[JPA Cate]

Originally Posted by djousset

@thinwater and @JPACate, thanks for the additional tips on protectant, MDR and color choice.
@AvionicsJoe, I'm not opposed to sewing a set of chaps as life support if I can get it to a reasonable condition.

Jim and I invented our way through our chaps. My bad. It would have been a lot easier for us if we'd watched the SailRite videos first. Ymmv. The sewing is easy, getting the pattern right requires the dinghy to hold air, and is easier if you have saw horses to get the dinghy off the ground. But, you could use red acrylic canvas, and use white binding on the cut edges, and add SOLAS reflective patch material so torches (flashlights) will show the size/shape of the dinghy at night, and have some pretty spiffy chaps.

Good luck with it, in any event.

Ann

[pau-hana]

Painted a "getting sticky" PVC dinghy with MDR. Been about 6 months now and very happy with the results. Like anything the key to a good job is the prep work. In your case the sticky is coming through the latex paint. I would use a strong detergent or citrus based cleaner to scrub it down. A very stiff brush or a 3M pad will help. You can be a bit more aggressive since you have the paint already on top of the PVC. MDR comes in grey (too dark) and white (too white) I bought one of each and mixed them to match the light grey of my PVC. Applied 4 coats of the MDR, it drys fast in warm weather. I taped off at the mid seams and only painted the top of the tubes. Spent a lot of time taping off the fittings on the tubes and the results are really good. Its easy to use the paint since its waterbased. A mini paint roller works great. Now everyone thinks I bought a new dinghy. Good luck....

[pbmaise]

"My goal is to not have the sticky return."

I have seen sticky plastic before. I think it was the handle on some of my tools. I used talcum powder. It is cheap, non-toxic, and seems to bind with the sticky PVC giving a nice surface.

Yes the sticky will eventually return...but talcum powder is cheap.

[gulfislandfred]

There is spray paint for vinyl lawn furniture the works well for boat fenders that have become sticky. It's flexible, and sticks to sticky plastic
I have also used it on a float coat that had the old plastic smell. Killed the smell, brightened up the float coat. The appearance of the float coat... Not suitable for fancy company, but servicable

[Kazamaran]

Diane. I decided to try out the Pettit Paint method on my 13 year old Mercury Hypalon dingy a couple of years back. I paid attention to the instructions verbatim. I figured I only had one chance at this. Lightly sanded and used acetone to clean until your finger chirps when you rub the hypalon. Also kept acetone away from any joints as best I could. First, I liberally covered all the seams with flex seal paint. Taped them all to get a good cut line over the seams. 3 coats- Black. Then I taped all the fixtures and attachment pads such as, handles, oars hold points, and the flex sealed joints, etc. (the paint will not stick to flex seal…) It was painstaking but I wanted it to look better than a garage job. Several coats of Pettit Paint later it looked brand new! I’ve had it on there a couple of years now and it’s held up really well. Very durable if done right. If I get a nick, I just prep it a bit the same way, touch it up and go have a beer. All good. So good luck with whatever you do. I’d have to say a proper application of the Pettit Paint gets a thumbs up.

[CarinaPDX]

For PVC dinghies, MEK is carefully used as part of a durable glue job. MEK softens the PVC before putting on the glue, resulting in a strong bond. MEK is wiped on sparingly; too much and it dissolves the PVC so care must be taken. I used this technique to glue the number strips and nav light mounts to my PVC dinghy with good result.

Hypalon is a very thin coating over neoprene, itself bonded to a fabric. Lightly sanding the hypalon removes it and allows the glue to adhere to the neoprene (which makes a strong glue joint). I suspect that adhesion to hypalon itself would be less than satisfactory.

Greg

[gordonhinds]

I bought an old pvc inflatable. It quickly became sticky. After a bit of research I painted it with house paint. Worked a treat. It’s now the same colour as my boat so very distinctive. And no stickiness. To clean it you simply wipe down and recoat. Or just recoat. The paint acts as a barrier to the Uv. I have had to reglue handles.