chalky surface on my new paint job

[DougyB]

Put the last coat on today, but every coat iv painted so far has had a very chalky surface before sanding, and thats with plenty of time in between coats. Im using 16 oz of alkyd enamel, oz of min. spirits, oz. of tractor enamel hardner,and 3.5 oz xylene per mix with 30 min in between mixing and coating... temps are 60 to 70 during day, 50 to 60 at night. Anyone else experience this? Did i do something wrong? Will this go away? The only thing i could think is buy alkyd enamel hardner instead. When i rolled this paint a few years ago it dried harder and quicker just by itself

 

[GT1000000]

Re: chalky surface on my new paint job

Are you Spraying or just rolling and tipping?...

If you are spraying...Check and make sure your compressor is drained of any and all water, and make sure you are using a good water separator between the compressor and your spray gun...

Sounds like you have moisture /humidity problems...

Could also be the paint is not compatible with Xylene for thinning, or maybe you have a hardener incompatibility problem, check with the manufacturer...

Xylene has a fast flash off point, you may be better off with Mineral Spirits or Paint Thinner.

Hope this helps...
GT1M

 

[Woodonglass]

Re: chalky surface on my new paint job

Yep, I would only use Xylene in low temps. Also how long were you waiting between coats? Minimum should be 4 hours. Were you wetsanding and then wiping down with acetone before the next coat? Post some pics so we can see what you see.

 

[DougyB]

Re: chalky surface on my new paint job

http://www.youtube.com/watch?v=F6KP...DvjVQa1PpcFMXsh2gADRKnZVFIpAjX6506IzKhVql5vA=

Gt, Im buying a water seperator today, and there was a bit of moisture in my tank. This could be part of the problem, but im not sure its all of it. Thanks for the pro advice for spraying though, I did not take this into account.

As for humidity, its been low on coat days, I paid great detail to it. Im either doubting the xylene or the hardner... to bad blue marine has worse customer service than an indian gas station

If i do have to recoat, how would you guys prep this surface for a new mix of paint. I plan on shooting samples first next time btw.

 

[DougyB]

Re: chalky surface on my new paint job

finally got a hold of a tech today at blue water, and didnt even want to talk about alkyds, kept saying buy uraglow ($300 between primer and top coat) ugh no help... why sell a product if you dont suggest to use it on anything

 

[Yacht Dr.]

Re: chalky surface on my new paint job

Hello Doug ..

Exactly what paint are you using ? .. brand wise I mean ?

I saw the vid you posted..yea..thats not good at all .. sorry..

I may have missed how you did the primer coats..but what did you use for the primer ?

Also..give Xylene the boot .. you dont need that at all ( very nasty stuff as well ).

I normally spray All of the topcoats at once. I leave about 30-45 min between coats. But if you mix the Whole batch up with your thinners .. then you might have had a flashoff of thinners in your bucket.

Meaning when you put your ( lets say 20% ) thinner in with the whole batch..then fill your cup..spray...wait to flash..then fill and spray again..you might have ( most likely ) lost a % of reducer in your batch.

If that makes sense ..

Any rate..what paint system did you use please ..

YD.

 

[DougyB]

Re: chalky surface on my new paint job

Yd, I used easypoxy's 6149 undercoater with just 15% xylene. The primer came out great, nice and hard. I waited the four hour overcoat window and shot it with the first coat of blue water marine's mega gloss alkyd enamel, with the mixture listed above. The mfg. called for a 16 hour window between recoats, and I did that for each coat.

I just called pettit and asked what they suggest for they're alkyd shipendec enamels, and they call for mineral spirits and no hardners were suggested. I feel like Pettit has a great deal more knowledge, at least on their lower end paints, then blue water marine does, and i wish I had used they're top coat in the first place.

 

[Woodonglass]

Re: chalky surface on my new paint job

Don't know a thing about BlueWater products. I know the Valspar & hardener worked great for me and several others here on the forum both on Glass and Tin boats. I used the Petit Undercoater primer as well. I'm thinkin there's a incompatibility problem with BlueWaters product and the primer OR the Xylene and possible Water Content in the line. If you do NOT have a Water filter on your compressor AND on your gun you I recommend doing that immediately. $40 bucks max.

For the compressor



For "Inline" at the gun.

 

[Yacht Dr.]

Re: chalky surface on my new paint job

Yd, I used easypoxy's 6149 undercoater with just 15% xylene. The primer came out great, nice and hard. I waited the four hour overcoat window and shot it with the first coat of blue water marine's mega gloss alkyd enamel, with the mixture listed above. The mfg. called for a 16 hour window between recoats, and I did that for each coat.

I dont think you used the proper thinner for your primer to allow you to overcoat without gassoff.

I think your primer thinner ( not the right thinner for 6149 ) was still gassing when you applied your topcoat.

The solvents attacked your topcoat in other words ...

This may have affected your primer coat as well. Let it gas off and stand for a week..see how ez it will be for you and a quarter in your hand to scrape off the primer.

If its too easy .. then you have to remove the paint and primer back to the surface. .. sorry ..

Thats why you should stick to one primer/paint system ( dont start adding xylene or touline or X,y,z components even if you read them on some other blog thingy ) .

YD.

 

[DougyB]

Re: chalky surface on my new paint job

Oh boy im feeling sick, what thinner is suggested? Im kinda feeling like im screwed

 

[Woodonglass]

Re: chalky surface on my new paint job

I've been doing some research. It appears your application and mixing was spot on according to the MFG specs.... They absolutely specify use Xylene for thinning and clean-up. 4 hours re-coat. However, they don't have a hardener for this paint. What Hardener are you adding? This could very well be the issue.

MEGA GLOSS ALKYD - THE NEW SCIENCE OF ALKYD ENAMELS - ALKYDTOPSIDE ENAMEL​

MEGA GLOSS ALKYD™ is a technically advanced, single component topside polyurethane enamel giving you a hardprotective coating for super high gloss, color retention, and long durability. MEGA GLOSS ALKYD is fast drying whichwhen brushed or rolled gives a smooth finish with excellent handle and flow. This widely used topside polyurethaneenamel has tremendous resistance to tough chemicals, cleaning solutions and ultraviolet light with its advancedultraviolet technology. Can be used on fiberglass, wood, aluminum and steel. It's like wrapping your boat in glass!​

SUGGESTED USES:​

​

​

​

​

Topside, Decks, Cabin, Masts, Bilge, Waterline,Boottop Striping​

LIMITATIONS:​

​

​

​

​

If applied below 50?F or above 95?F dry times might be tooslow or too fast for proper application​

COLORS:​

​

​

​

​

Available in 10 factory package colors​

FINISH:​

​

​

​

​

Gloss​

VEHICLE TYPE:​

​

​

​

​

Alkyd Resin​

SOLVENT TYPE:​

​

​

​

​

High Flash Naptha, Xylene​

VOC:​

​

​

​

​

2.8 lbs / gal, (330 grams / liter)​

SOLIDS BY WEIGHT:​

​

​

​

​

50%​

WEIGHT PER GALLON:​

​

​

​

​

10 lbs. per gallon (varies by color)​

RECOMMENDED DRY FILM:​

​

​

​

​

4.0 mils​

COVERAGE:​

​

​

​

​

Theoretical coverage at two mils dry is 400 square feet pergallon, and recommended thickness of 4 mils dry would require 2 fullcoats.​

VISCOSITY AT 75?F (24?C):​

​

​

​

​

70-80 KU​

AVERAGE DRY TIME 75?F:​

​

​

​

​

Dries to touch in 4 hours. Lower temperatures& higher humidity will slow down dry times.​

RECOMMENDED REDUCER:​

​

​

​

​

Xylene for spray application (10-25%), HighFlash Naptha / Xylene (5-10%) for brushing and rolling​

RESISTANCE TO:​

​

​

​

​

Chemical Resistance, Abrasion, Oils, Grease, Rust,Corrosion, Mildew, Chipping and Fading​

APPLICATIONBrush/Roll:​

​

​

​

​

1/2” nap mohair metal, lambskin, phenolic core roller. Keeproller wet. Roll in one direction, rewet, then cross roll. Product can bereduced as needed with Xylene to allow proper flow out and performance.​

Spray:​

​

​

​

​

Conventional Air Gravity Feed 59-70 psi, Tip Size .055 -.070, Airless2200-2500 psi, Tip Size .013-.017. Product can be reduced with Xylene asneeded for proper flow out and performance. For Air Spray reduce 10-25%with enamel reducer (Xylene.).​

SURFACE PREPARATION:​

​

​

​

​

Abrade with 80-240 grit dry sandpaper or equivalent.Solvent wipe down to remove all sanding residue.​

POT LIFE:​

​

​

​

​

Not Applicable​

SHELF LIFE:​

​

​

​

​

Minimum 36 months​

MIXING:​

​

​

​

​

Mix for 5 minutes, making sure that all solid material is mixedthoroughly.​

PACKAGE:​

​

​

​

​

1 gallon cans, 5 gallon pails, quarts​

CLEANUP: Xylene for Equipment

 

[fmjnax]

Re: chalky surface on my new paint job

I have this same problem on the stripes I painted on my hull. I still haven't figured out exactly what happened, but basically I figure it was as YD and WoG posted; a problem with the hardener. The stripes are soft enough that I can scratch the paint with just my fingernail, even 4 months later! I did everything as per the specifications and the same way I did for my trailer and hull, but something went sour. In my case, it could also be because I rolled the stripes instead of spraying (I sprayed the rest) and/or that I put the paint on too thick. I've tried to sand layers off, but no matter how much I sand, it still has the problem. I'm going to have to sand it ALL off, put down new primer, and repaint the stripes (and this time I'm going to mask and spray!).

 

[DougyB]

Re: chalky surface on my new paint job

fmj, have you got to your primer yet? I know I'm praying I dont have to go all the way down to the primer, but Im hoping even more its not below the primer.
In any case, you beat me to it wood, i was gonna post the spec sheet. If yacht dr.'s right about my primer giving gas off, well I have my stupid math equation to blame. Pettit uses their own thinners, so instead of calling customer service, I figured I'd look at their alkyd paint, and see if they suggested the same thinner for 6149 as they do their alkyd, which they do....So obviously pettit must also use a xylene thinner with their own name on it for their alkyd paint too right.....wrong!! called yesterday and the thinner they use on they're alkyd is actually min. spirits, which is what I guess I needed to use on the primer. Im starting to find not every alkyd paint is the same. Reading online, you find so many different thinners thrown out there, from japan dry to napth, min. spirits, xylene and acetone..... some with hardners, many without etc.
I have found there are specific alkyd hardners as well, which i didnt know two days ago, and not every manufacture suggests them.

But to get to the point, I'm looking at three things that are possibly killing me, one being the enamel hardner that is made for oil-based paints, water in my lines, and three my primer gassing off. One of these three, or the combo, did me in.
Im definetly doing samples before i spray a mix next time. One thing I did notice on the last coat, when I would take the top of my paint cup off under air pressure, a liquid like mixture would bubble to the top, and the paint in that bubble would be seperated into a cluster of little balls of paint, instead of a uniform liquid.... any insight?

 

[fmjnax]

Re: chalky surface on my new paint job

I didn't use the same system that you did, so our problems might not be related, but no I haven't gone down to the primer yet. My initial thought was that I just rolled the paint too thick so I let it sit for a long time to see if it would gas off over time and cure up. After a month, the top was still very soft. I wet-sanded a bit off and waited again. Same thing. Then I hit it with some 150 and took quite a bit off and left it for 2 months.... and same thing. It appears to be soft entirely.

No matter how much I sand off, I end up with a chalky residue. My paint color is a deep maroon, but with the chalky stuff on it, it's almost pink! It cannot be washed off with water, acetone, thinner, or anything else. However, if it is wet, it is invisible. Every time I was it, it tricks me to thinking that I finally got it off... but once it dries, the chalky haze is back.

In my case, I KNOW it's not my primer still trying to off-gas. After I shot the primer, I had a good gap of time before I was ready to shoot the paint. Besides, the rest of the hull came out just fine. I also know it wasn't water in the lines because, well, I rolled it. Again in my case, I used the Valspar paint and TSC hardener for the hull and sprayed it. For my stripes, because it was a custom color, I used a marine/industrial oil-based paint from Sherwin Williams with the TSC hardener and rolled it. The only difference I had was the paint and the method. However, I used the same SW paint for my trailer and it came out perfect (but it was sprayed). When I look at all the scenarios and differences, it seemingly boils down to 2 things: 1) either something with my hardener went south and/or 2) I rolled the paint too thick and it never got a chance to cure

I've kind of shelved the problem for now. I'm a week or two away from being ready to paint my top cap so I figured I would re-do the stripes when I do my cap; especially since I will be spraying the cap. Roll/tipping is NOT for me!

Sorry for the long-winded post here. I wish I had more definitive information, but hopefully something I typed will be useful.


**EDIT**
I just re-read the paragraph of your last post. That definitely does not sound right. Kinda sounds like trying to mix oil with water, ya know. I'm not sure what would cause that, but I know I've never seen that when spraying (though my paint spraying experience is quite minimal).

 

[DougyB]

Re: chalky surface on my new paint job

sure is a tricky situation...more in your case then mine... did you use the hardner on the trailer too? Im thinking these hardners arent as compatible as we would think.... even the can says for all oil-based enamels, im doubting it

 

[Woodonglass]

Re: chalky surface on my new paint job

I've still been researching and would like you to experiment a bit. The bluewater alkyd paint supposedly unlike other alkyd paints has some special formula that allows it to harden to 80% WITHOUT an added hardener. If you have some scrap metal, paint it with the paint ONLY, NO HARDENER and let it cure over night and see what you get. I'm REALLY thinking it's the hardener. If so, then you'll need to remove the Color Coats but NOT the primer. Then repaint with just the paint only thinned with xylene as recommended by the MFG. Thats my recommendation.

fmnjax, does your paint come off on your fingers as a powder like DB's does?

 

[Yacht Dr.]

Re: chalky surface on my new paint job

Yes it was the Primer coat that I was wondering about. You already called pettit ( I just did myself ).

They suggest the use of 121 spraying reducer ( up to 10% ). They did say that you Might be able to use xylene in a pinch..but not recommended.

Also..you have to apply the primer ( yes multiple coats is fine within the 2-16 hour window ). However you then Wait the 16 hours..then scuff the primer for the topcoat.

This is NOT a skipsand primer coat system...The recoat time specified for the EZP was for itself only.

Basically its just like any other system .. Prep..Prime..reprep..topcoat.

You cant get from initial prep to finished topcoat in one session.. sorry.

I still think its a gassing off problem. Your primer Was still gassing when you applied your topcoat to it in 4 hours.

As I suggested above..you can Try to let the xylene flash out of the coatings after a week or so. The paint may or may not harden up.

Here is the rub.. and I do not wish to make you more upset.. but even if the paint did harden correctly after a while..it may not adhere properly. It is possible that it could lift in the future. I just do not think the prep was correct between the primer and the topcoat.

Its really hard to say at this point as what to do/recommend.

.. ..

As you already know..water is bad bad news in your spray lines ( even your for your blow off ).

It is hard to say what was going on with your paint on the top of the cup ( bubbling effect and such ) .. but I can tell you NEVER EVER spray the last few OZs' of paint out of the gun. It is solvent rich in most cases .. no good IMHO ..

Its better to run and dump a little more paint into the cup then expend every last drop out of it ( you should always have at least a few ounces left in the gun when finished ) .. better to buff out some dry over spray then have a foot or two of solvent rich paint being shot on your product ..

Just trying to be as honest as I can ..

YD.

 

[DougyB]

Re: chalky surface on my new paint job

wood im gonna do it right now, I was gonna do it when my compressor parts came in but ill use the same variables as when i sprayed the four coats, and it will make a more accurate test anyways

 

[Yacht Dr.]

Re: chalky surface on my new paint job

We posted at the same time lol..bump for your notification ..

YD.

 

[fmjnax]

Re: chalky surface on my new paint job

I don't want to take too much away from DougyB as it's his thread and the more information that comes up the less related our issues seem to be, but no, my paint doesn't come off on my fingers. I guess my problem is more of a haze than an actual chalky substance. I must have missed the part explaining that his is coming off on his fingers; my apologies.

DougyB - Yes, I painted the trailer with the hardener and it came out just fine.