# What's the paint problem here? Capillary action?



## Jim Schulz (Aug 10, 2009)

I've stripped the cab down to bare brass, sprayed one coat of Krylon Ruddy Brown Primer, waited an hour, then spray painted Krylon Gloss Black. What has happened so that the black paint is not getting into the corners? Could it be that the capillary action of _gloss_ black is causing the paint to creep up the sides and stay out of the corners?











Can I paint over the gloss black with satin or matte black to solve this problem?

Then cover with a clear coat to get the gloss shine?

Finally, can I paint over the gloss black with Krylon BBQ & Stove black (I've got some of that leftover from another project)?

Thanks for your help. I don't want to have to strip it all down and start over again.


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## stevedenver (Jan 6, 2008)

well im no expert-but i am guessing that the primer paint coat slightly gathered and pooled in the corners was thicker-and therefore not as dry as the flat surface- 




therefore the corners might have been gassing out (ie still emitting solvents which make the paint flow) 

and caused the gloss to move away 

 dont know but i do know that when spraying over other paints this can happen -and even tho both were krylon -there may have been a difference in formulas which made them slightly incompatible- I've had this happen too-sometimes there are different solvents-or they take a long time to fully gas out 



a cure-so to speak!-would be to let it dry for a week or two and spray again with black-this time it should actually pool in the corners 






you mention BBQ paint  -so i presume this is live steam-not really relevant perhaps






id let it dry -spray again with the gloss (or a paint of the same formula) gloss should adhere well to gloss -as it might remelt upon application)






i dont know what flat will do on top of gloss-might work-then gloss again -probably just fine-i presume these are enamels and not polys






i think the key for you to avoid a strip is to let this thing really dry-even consider the old oven at say 120 for a few hours  if you live in a humid area


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## tmtrainz (Feb 9, 2010)

Having used Krylon paint before, i can attest that the solvent to paint ratio is rather high, and therefore it takes quite a few coats of paint for total coverage. I think that your problem is that you need more paint, focusing on all of the edges and corners of the trim detail. 

Just curious, but how many coats of the black did you spray?


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## Steve Stockham (Jan 2, 2008)

I would wait at least 24 hours after spraying primer before I would apply paint. The first coat never covers everything! (There may indeed be capillary action!) I would give at least 24 hours before putting on the second coat of paint. The point is that it's infinitely better to take a few days and apply a number of very thin even coats than to try and rush it and "get it all in one!" A bit of color sanding with 1100 grit or finer also helps between coats. Of course, paint is also extrememly good at covering up niggling little imperfections! If that's the case, more can sometimes be better!


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## Jim Schulz (Aug 10, 2009)

That's my problem - impatience. I've put on just one coat of paint, but perhaps you can see at the top of the cab that I started to put on too much paint so that it started to drip. The cab is from an Accucraft Legend live steam 4-4-0, but the BBQ paint was from another live steam project. I'm trying to match the gloss black of the tender, which I don't plan to repaint.


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## propbreaker (Apr 25, 2010)

I painted for a living . I paint cars and Semi and even aircraft. The problem is you painted to heavy and did not allow what is called flash time to occur. I would start over strip it down an clean the up very well before starting over. Make sure to scuff the surface to promote adhesion of the paint to the surface. Also when you spray the primer on spray it on in light coats and allow at least 20 minutes between coats when you have coverage let it dry for 2 to 3 hours . then start to apply color same thing light coats and 20 minutes between coats. You should come out with better result. SPEED AND PAINT DO NOT MIX!!!!! That was the thing I learned in all my years of doing it


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## stevedenver (Jan 6, 2008)

well there you have it -an expert! 

i knew it has something to do with timing....... 

strip it while its fresh-should come off pretty easily


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## Jim Schulz (Aug 10, 2009)

Ya sure I just can't wait a few days to let it really dry and put on another coat, or is it never going to get into those corners?


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## East Broad Top (Dec 29, 2007)

I'd be tempted to scuff it lightly with some fine steel wool and just repaint it. I've had similar happen on occasion, and a second coat does fix it. And if it doesn't, then you strip and repaint and you've lost nothing. 

Later, 

K


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## Jim Schulz (Aug 10, 2009)

Thanks Kevin. I'll try the steel wool/second coat route. Couldn't hurt. Why does my heart rate go up and my hands get sweaty whenever I get to the painting step of my projects? If it's not one thing it's another.....


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## Spule 4 (Jan 2, 2008)

A friend had a vintage Panhard cabriolet painted a few years back. The only way the guy would do vintage lacquer work was to do it WAY after hours and after some "herbal" intake. He wanted to take his time and be mellow about the whole thing was his claim. 

Crazy? The car had not a fisheye, run, dirt spec, etc....


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## DKRickman (Mar 25, 2008)

You can strip and repaint, or just keep painting. Starting over will give better results, whereas adding more paint will cause some detail and crispness to be lost. Your choice - ease vs. quality. 

Now, to be technical, that's not capillary action, since there isn't any capillary to be "acting." It is, however, the result of the same thing that causes capillary action - surface tension. The paint wants to bead up on the surface. It's not so much the primer building up in the corners (although it almost certainly has as well) as the black paint pulling away from the corners to form a puddle in the middle of each surface. 

I find that I get results like that when I put down too much paint, and/or don't hold the can or gun far enough from the surface. The paint needs to go on thin so that it can't puddle, and a little tacky so that it sticks wherever it hits. You get it thin by moving quickly and not focusing on one spot. You get it tacky by pulling away a bit, which gives the individual droplets enough time to dry just enough. Of course, taken too far, that lrads to orange peel, so it's a balancing act.


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## DKRickman (Mar 25, 2008)

You know, I just looked at the photo again. Maybe you should leave it alone - it kind of looks like old varnished wood to me.


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## Bill Martinsen (Mar 4, 2008)

Krylon has been my favorite rattle can paint for many years, but not anymore. I recently had the same problem that Jim had. In addition, the glossy Krylon paint I was using over gray Krylon primer caused the primer to get gummy. I've heard that Krylon made some changes in their paint formulas (probably to comply with EPA regs). I've bought my last can of Krylon. After spending many hours constructing a model, I'm not going to risk ruining it by using inferior paint.

Bill Martinsen


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## HeliconSteamer (Jan 2, 2008)

I recently painted a steam project with Krylon and had reasonably good luck. I had some coverage trouble on inside corners, but the paint seemed to go on and adhere well. Part of the project was primed and then painted more than a week later with no ill effects. The other part had to be repainted and was primed and then top coated in a matter of about 20 minutes. There is no apparent difference between the two types of painting.


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## East Broad Top (Dec 29, 2007)

I know with the "old" Krylon, there was what I'd call a "window of non-opportunity" during which you had best _not_ put a second coat on the model. If you painted the top coat on top of the primer within about 1 hour of each other, you'd be fine, but much beyond that, you had better wait a day to avoid the paint crazing. I don't know if the "new" stuff is similar, as I've just gotten used to painting primer and top coat within an hour of each other and plan my painting days accordingly. 

Personally, I've not had any trouble with the "new" Krylon paints. I've not mixed "old" and "new," and I wonder if there's some incompatibility there that may be giving people fits. But for my experiences, I've not noticed any difference in performance at all when using the new formulations on my models. 

Later, 

K


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## David Leech (Dec 9, 2008)

Yes, the NEW Krylon still has a time where you should NOT add another coat. 
i just managed to find that out the other day!!! 
Also, it does NOT like alcohol. 
So do NOT paint live steam loco parts if they are alcohol burners. 
A spill while refilling will result in 'melted' paint. 
All the best, 
David Leech, Delta, Canada


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## Ralph Berg (Jun 2, 2009)

Krylon and Rust O Leum both have the same directions...........second coat before 1 hour, or after 24 hours.
Ralph


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## Bill Martinsen (Mar 4, 2008)

Instructions on the can of "new" Krylon Gray Primer (51318) say "Recoat or topcoat anytime." Instructions on the can of "new" Krylon Safety Yellow (1813) say "Recoat: Anytime." These are the two cans I used, with very poor results.


Bill M.


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## tmtrainz (Feb 9, 2010)

As I mentioned before, Krylon has a high solvent content. It dries relatively quickly, but in return, you often need more than one coat to cover whatever your base preparation is. Krylon will ususally be dry to the touch after an hour or so, sometimes sooner. 

Rustoleum products, on the other hand, have relatively low solvent content. Rustoleum is excellent for those that have time and patience to let what ever item you paint sit for at least 24 hours to dry. Before 24 hours, don't touch it to see if it's tacky, it still is. 

There's trade offs with each product. Krylon wins for quick drying time, but you need several coats to achieve full coverage. Rustoleum loses for drying time, but full coverage can be achieved with one coat. 

You can decide for yourselves what product you like better. 

Tom


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## Jim Schulz (Aug 10, 2009)

Third coat, each application after a two-day wait: 










And for comparison purposes, the first coat:


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## East Broad Top (Dec 29, 2007)

Looks sharp! Now, the rest of the locomotive...  

Later, 

K


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## tmtrainz (Feb 9, 2010)

Looks good!!!!!


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