Friday, September 12, 2014

Paint

 I am going to finish up this part of the blog by saying that I came very close to my goal.  But I have given myself permission to quit obsessing over this project and get back to my normal life for awhile, whatever that is.  This photo shows the present status of the seat...upper seat back with a gloss coat of enamel, side panels and lower seat back sanded and ready for same.  The sanded coat is the third coat of enamel that was allowed to remain. Perhaps as many as six coats were washed off with solvent before they dried.

This pretty shiny surface does not hold up in the light of day.  Because the lighting was poor when I painted, and because the painting area cannot be made dust proof, the surface actually has an irregular gloss and a lot of dust in it.

Shortly after this photo was taken we had a wind storm and the inside of my painting tent looked like a tornado had blown through.  That was the end of the project for now.  Fortunately, nothing will be harmed by allowing the paint to cure before being "flatted down" again and recoated.  The important thing is that the wood is all wonderfully protected.

Happily, I learned a great deal about the paint, what I should expect to see with each coat, sanding, brushes, light and the all-consuming need to control dust.  I will share with you what I have learned.

So, what happens next, after I get my fill of riding and driving my neglected horses and catching up on all the heavy yard work and house work that have been neglected as this little wooden crate has dominated my every waking hour this summer!

I am going to prepare the body for paint.  That will be the next phase of this blog.

I will move the painting into the shop, which will have improved lighting and a "clean room" enclosed in clear plastic, with filtered air.

I will buy a different paint brush.  The one I am using tended to "split" and force me to work an area of fresh paint more than was good for the finish. I think that is where I got into trouble with the areas of faded gloss.

I will resume the painting project with considerably more confidence!

So here's my experience!

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Carnation Milk is the best in the lan'
Comes to the table in a little red can.
No teats to pull, no hay to pitch,
Just punch a hole in the sonofabitch!

That silly old advertising jingle pretty much sums up my understanding of paint until a few days ago.  I took my expensive paint, dipped in my expensive brush, brushed the paint on my meticulously prepared surface and ended up wiping off three consecutive coats before they could dry.  The results were hideous!  Brush marks and runs, no matter how carefully I applied the paint.  Time to retreat into the information packed halls of the internet.

When one is spraying modern automotive paints - which we are not - there are precise formulas to follow when combining ingredients to prepare the paint for spraying.  In brush painting, we do not have "instructions" to follow, so to speak.

As it turns out, the expensive paint may not be ready for brush painting right out of the can, just as Carnation evaporated milk isn't exactly the same thing as whole cow's milk.

The paint usually has several methods of application; brush, roller,"roll and tip", airless spray, conventional spray.  The manufacturer has no control over the method used for application, the surface to which it will be applied, or the expected results.  Nor does he have control over the conditions of atmosphere under which the paint is applied. So he offers a product that can be adapted to suit the requirements of the painter.  That generally means thinning.  Yes!  Even for brushing!

I always thought that thick paint, the way it generally comes out of the can, meant that it had enough substance to flow out into a smooth coat.  I don't know how many times that incorrect assumption caused paint failure for me.  The instructions always say to apply several thin coats, and I always try to put that paint on in the thinnest coat possible, but it usually doesn't work well, even on a horizontal surface that's been sanded as smooth as glass.

There is more.  Modern environmental laws and regulations specify limits as to how much VOC - volatile organic compound - that paints can contain.  VOCs are solvents that evaporate into the air.  Sufficient solvent is required for the paint to flow out correctly.  But your paint may not have enough solvent to give you the glassy surface you seek on your carriage!

You will see a notation on the label stating the VOC content,or you can look it up on the Material Safety Data Sheet available from the manufacturer.  You may see a warning that adding solvent will increase the VOC.  As a consumer, I have been uninformed about the relevance of that.  In simple language, it means that there may not be enough solvent for proper paint flow out, and if I add more, I may actually be breaking the law!

Further, the manufacturer's instructions may allow you to "add up to 10% solvent" for brushing or "10-15%" for spraying.

Translation:  That is all you can add to keep the product VOC within legal limits.  It has nothing whatever to do with paint performance.

Since we do not have a "tech sheet" to guide us beyond this wilderness marker, we need to gain experience with our chosen paint and various thinners/reducers which MUST be compatible with the paint.

Take no chances! Use the thinner recommended by the manufacturer!  Some explanation of common thinners:

When conditions are cool and damp, we may want a thinner that will dry faster, so it won't take a full day for the paint to become dry to the touch!


Naptha can usually be used, as it dries a little faster than ordinary paint thinner.  In some cases, "Japan drier" can be added sparingly.  It is an additive that I believe, causes catalytic (chemical reaction) drying, but it can make paint brittle.

For slower drying, I think plain mineral spirits or paint thinner can be used.  You would want slower drying on hot days because the paint may dry too fast for you to control it.  Your brush will get sticky and the paint won't flow out.

At any rate, I am guessing that in order for a thin coat of paint to flow onto your carefully prepared surface, it should virtually have no brush marks in it as you lay it on.  Don't take that as gospel from an experienced painter,but that pretty much paraphrases a passage from one of my coachpainting books. It seems that after this recent experience, that is just about what the thing needs to look like as you are working, and that very well may mean thinning your particular paint with a suitable thinner.

Pettit offers a "brushing thinner" and a "spraying thinner".  I believe the spraying thinner dries much faster.

Following the paint can instructions can sometimes guide you in thinner selection, but you are somewhat on your own when determining how much, if any, thinner you are going to add to your paint.  Experience is your friend. The paint needs to be thin enough to lay on perfectly, but not so thin that the pigments are diluted too much.  You need good coverage. Whether you are within legal VOC limits when you are done is none of my business.

When I finally arrived at the earth shattering epiphany that I needed to thin the paint in order to achieve proper flow-out, I started with one half ounce of Pettit brushing thinner to five ounces of Pettit EasyPoxy paint.  I painted part of the carriage seat with that and was ecstatic with the results, but I didn't feel it was just right yet, so I added another half teaspoon of brushing thinner to my remaining paint.  It reduced the slight brush strokes by at least 50%.

Ultimately, for the seat back above, I came up with a mixture of 4 1/2 ounces EasyPoxy, 1/2 ounce Penetrol (which may dilute the pigments, but adds shine and adhesion and improves flow-out) and 1/2 ounce Pettit brushing thinner.  I got gorgeous flow-out with this, and good coverage, but my light was poor enough to be difficult to see the black surface well, and my paint brush was splitting, leading to missed spots which had to be gone over too many times, and some of which remained in the final film.

This is pretty much where the thread ends for now.  But here are some photos of the process, and some comments.






Before the main event, while the wet-sanded exterior of the seat was drying, I took the opportunity to put a coat of enamel on the inside of the seat.  A great shot of what *no* surface preparation looks like after painting. Very rustic.  This will of course, all be covered with upholstery.  But all surfaces of the seat are now protected.







My first coat of paint, while it was still wet, was enough to bring a normally mature, rational adult female to a state of sniveling self pity!  I had sanded the guide coat off the primer with 220 grit wet sandpaper.

I KNEW that 220 grit sandpaper was too rough!  But it was several grits finer than the manufacturer's 150 grit. If you double click on the photo you will see that the surface is anything but glassy.

NOW...much wiser than when I took this picture, I realize a number of facts that were unavailable to me before.  The first is that with meticulous surface preparation, it is likely very unnecessary to use a "high build" primer as I have on the seat.  The seat surface was nearly perfect before I proceeded to prime.

When the guide coat was all sanded off, what I could not see is that the surface was still a bit far from level.  That, and the visible sanding scratches in the paint made me feel like a failure.  But actually, what I was seeing wasn't all such a bad thing.

It was just the first coat of paint, and the first coat of paint needs a rough surface to grab on to, so although I still think 220 is awfully coarse, it provided the necessary roughness for the enamel to grab on to.

The dark gray of Schwartz sanding primer is quite a bit easier to see when the primer coat is level, so that should be a help when I prepare the body for paint.

Back to the first coat of paint.

As the paint dried, it did an amazing job of leveling, and didn't look half as bad as when it was wet.  So I felt a lot better.










Here is a macro of the surface.  I'm sharing these pics so that first-time painters will know what to expect.  Look at the sanding scratches that have "photographed through" to spoil the shine.  Nothing could be more graphic to demonstrate the need for a perfectly prepared surface!  You can double click on any of these images to get a closer view.

The speckles of dust are very difficult for me, or anyone, to eliminate, as I do not have a dust-free environment.  Right now I have an air ionizer going in the tent to try to help eliminate some of the dust, but it is very breezy and hot outside today, so it wouldn't be a good day to paint.

Now, for comparison, here is a singletree that I painted a day later, with its first coat of the same paint!

The difference is the primer and the sanding.

For the seat, I used a heavy bodied, "high-build" primer (Pettit) and sanded it back "level" with 220 grit sandpaper.

On the singletree, I used a less heavy bodied, hard drying sanding primer (Schwartz).  I sanded it back part way with 220 grit, then finished with 400 grit.  The first coat came out nearly flawless.  All coats of primer and paint were brushed.  The difference is in the primer and the sand paper.

Now!  The rest of the carriage comes down to primer selection.  After seeing the results of my first coat of enamel on the heavy, high-build primer, I had to ask myself, with all the laborious surface preparation that preceded the first coat of paint, why did I elect to use a "high-build" primer in the first place?  There were no defects to fill!

The only answer seems to be, it seemed like the right choice at the time! For now, it looks like I will be leaning more toward using the Schwartz sanding primer for the rest of the body.  I expect no further need for high-build products, particularly since the wood on the body is so beautifully preserved.

And even now, it doesn't pose a problem.  We sand between coats of paint anyway.  The seat, in its present state, just poses a little bit more work.


And so once again, the little carriage seat is trotted outdoors into my shady sanding place.  Ugh.  This shows that the "guide coat trick" is not foolproof.  Especially with white primer!  At least with the dark Schwartz primer you can really see the results of your sanding!

So here, I've taken a few careful strops with 400 grit wet sandpaper, and immediately, we can see why our first coat of paint came out so dismally dull.

Once again, these brush marks and dust must be sanded out completely before the next coat is applied or they will be WORSE! Happily, these defects are now quite shallow and sanding is considerably easier.

IMPORTANT TIP!!  Just putting on more paint will NOT solve the problems shown here.  Adding paint to a surface like this will only make it WORSE!  Like cutting a board twice and discovering it's still too short!  Or adding more saddle pads under a too-narrow saddle to try to make it fit a wide horse. Defects in the surface must be leveled by sanding or the quality of the job will just continue to deteriorate.

IMPORTANT TIP NUMBER TWO!!  It's going to take at least 24 hours in good weather for your paint to be dry enough to sand!  If your sandpaper clogs up easily while you are wet-sanding, STOP and wait for the paint to dry another day or so, believe me if you don't, you will be sorry!  The paint will roll up in sticky wads on the surface and it will be practically impossible to get them off!  If you have big, thick drips, you may want to shave the surface off with a razor blade to allow the paint underneath to dry.


(Following was written as "stream of thought)

An hour or so of light but thorough wet sanding with 400 grit paper yielded a really nice, smooth surface.  Yes, I cut through to primer in a couple of places, but that's not a problem!  There were a couple of almost-drips that were a little too soft yet to sand well, so those will be last minute touch-ups before Coat Number Two.  Today, it's too hot and windy to paint.  Hopefully tomorrow.

And yes, of course, learning to use a paint gun would eliminate 90% of the labor.  But not everyone can buy a big enough air compressor and a paint gun.  And the number of problems an inexperienced person can create with a modern spray gun and a traditional paint is mind boggling. I really want to stress that you can do a great job of painting with just a brush, if you have the patience to do all the necessary sanding.

Sanding got easier on the enamel, because the surface lumps and bumps (basically, the primer and the poorly-flowing paint) became fainter and fainter.

I ended up sanding what I thought would be my last time, with 600 grit sandpaper, as 400 grit was still showing sanding scratches.

 When I painted this time, I ran into problems trying to "control" the paint in the hot, dry weather, and even once I found my "magic formula" I wiped off coat after coat of wet paint because things would begin to go wrong, the brush would drag, and I would panic.

At one point I did a beautiful job on the seat back, and while it was still tacky, I made a horrible mess of the lower part of the seat.  I carefully solvent-wiped all the wet paint off the bottom half, and in the process, the cotton rag rained lint all over the tacky seat back! So that all had to be wiped off again, and it was nearly too late!

So!  That is why the upper seat back is painted, and the bottom is sanded as I end this part of the blog.  I learned not to be greedy and try for too much all at once.  I got that upper seat back painted on a good day and QUIT.  A couple of days later when I wanted to try for the bottom part, the wind had turned my painting tent topsy-turvy.  I was so fed up, I finally said QUIT, BARB!  BEFORE YOU REALLY SCREW UP!!  REST, BUILD A BETTER PAINT BOOTH, GET A NEW BRUSH, AND OPTIMIZE YOUR CHANCES FOR SUCCESS INSTEAD OF BLUNDERING THROUGH.

Happily, most carriages come with handy, built-in "sections". One need not get the whole thing painted in one day, and as beginners, learning to control the paint mix, the application and the brush, it might be best to stop for the day when you're ahead, instead of experiencing such heartbreaks as I described above.

And so, my friendly readers, I will leave you alone for awhile.  I'll pick up again with carriage body repairs, new priming, sanding and painting strategies.  Thank you for sharing my adventure with me!







2 comments:

  1. HI Barb CDLer Kay here. I have found your writings very interesting, as I, too, like to do "projects" and have struggled with the paint and brush streaking. I have learned a lot from your tutorials, and say Thanks for the info. It has taken me years, to learn the little I know, however, I do have lots of fun with the projects. Dust and bugs in the finish are sure hateful. Plus the wind here in TX. Best wishes, Kay

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  2. Hi Kay! I'm looking forward to trying a few new ideas, a cleaner paint room, and new brush in the upcoming weeks! Learning is slow,when a person only does one of these vehicles every few years...and there's no real central source of information! Thanks for writing!

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