Spraying SW ProClassic - Dilution needed? Revisiting (and recanting earlier statements)

Henry W

HenryW
Senior User
A few weeks ago someone asked about spray guns for wood finishes, and a SprayIt 33000 LVLP gun was recommended; I have and use this gun.
Here's the link:
Seeking HVLP gun advice

OP later asked if this LVLP gun was capable of spraying latex - because he saw that in his future.

I commented that product choice was paramount (I still stand by that part), and that I had successfully sprayed Sherwin Williams Pro Classic acrylic enamel paint UNDILUTED (because I did not recall adding water; this is the part that needs revisiting).

Golfdad's commentary was :
Pro Classic won't spray directly. If you do get it to spray, you will probably not have a great finish. (HW edited for clarity, not content)
Well in later work (after this discussion) I tried the experiment; the results spraying this product undiluted (straight out of the can) were acceptable (to me) but the process was not. Comparison on the next coat, which I thinned by 5-15% (by eye, not measured), was that the results were also fine but that the process was easier. Recall that I am not a finishing guru, and this SprayIt 33000 is my only tool and my only spraying experience.

Undiluted the finish delivery was uneven - when the finish was delivered in the flow, it seemed to lay down fine, but the amount latex being delivered was NOT consistent. There were no blobs or anything (i.e. atomization was acceptable), but there were times when there simply was no product in the air stream. That makes laying down a consistent finish much more difficult.
Diluted spraying (done 3 or 4x since the experiment spraying undiluted) has not had any issues.
Note that this was a single experiment and there may have been other issues that caused my results (improper/insufficient gun cleaning prior to first usage with the latex, for example).

So for maybe slightly different reasons than Golfdad described (oh so briefly) I absolutely AGREE with him:
Diluting SW ProClassic Acrylic Latex Enamel before spraying works better (caveat - under the conditions I tested; your own tests likely needed for your own equipment).
 

Gofor

Mark
Corporate Member
Adjusting viscosity has always been an important facet of getting an even spray distribution. For latex-based paints, using a additive medium like Floetrol will also help reduce viscosity without getting a "watered down" result from using too much water.
 

agrieco

anthony
Corporate Member
Thanks for the follow up. This is great info.

two follow ups
1) did you dilute with water or something else?
2) what tip size did you use?

thanks
 

JimD

Jim
Senior User
I do not have that gun, I use a Fuji Mini-Mite 3, but I had to thin the Resisthane I was using recently. I used Flotrol. I do not even mix the paint up well, apparently, before dumping it in the gun and I was getting inconsistent results. Sometimes I had a nice spray pattern and other times, little was coming out. Once I even had a few globs. But a quick splash of flotrol in the cup resolved the issue. Great thing to have on hand.
 

Henry W

HenryW
Senior User
Two follow ups
1) did you dilute with water or something else?
2) what tip size did you use?
1) Water dilution - in the cup and shaken (not stirred).
2) I believe the max size tip supplied with this gun is 1.7 mm, which is what I used.
 

golfdad

Co-director of Outreach
Dirk
Corporate Member
Guys this my formula based on my gun and compressor. I always spray around 22psi. Using pro classic I use 3oz water to 16 oz of Pro Classic adding about 1/2-3/4 oz of Flotrol. As Henry said this is sprayed with a 1.7 tip. I would say any tip from 1.7-2.0 is fine but you might have to adjust your formula to your tip
 

chris_goris

Chris
Senior User
I recently sprayed a project with SW Pro/Classic Latex.... it did not go well. I did dilute it some, but my gun just didnt like it ( a Fuji). I WOULD NOT RECOMMEND IT!. Use the ALkyd version instead if you can. I say if you can because I learned they cannot tint the oil to dark colors for some reason. I was using a near hunter green color. I ended up having to topcoat the whole project with Polyurethane to even out the surfaces and texture.
 

Robb Parker

Robb
Corporate Member
I am curious as to why any of you use a house paint on cabinets rather that, pre-cat CV, post-cat CV or some water base lacquer made for wood and cabinet finishing? Is it the cost, availability, lack of knowledge of products, or of spraying those products. I am not trying to be insulting, just curious.
 

Henry W

HenryW
Senior User
I am curious as to why any of you use a house paint on cabinets rather that, pre-cat CV, post-cat CV or some water base lacquer made for wood and cabinet finishing? Is it the cost, availability, lack of knowledge of products, or of spraying those products. I am not trying to be insulting, just curious.
Robb
Can't speak for others, but I don't do what you are suggesting. I have sprayed 'house paint' (SW ProClassic Acrylic Enamel) on passage doors (for my home), and used shellac, pre-cat CV, and water based lacquers on furniture. I have not sprayed cabinets at all.

Not sure anyone else has specifically mentioned spraying cabinets, but maybe they have. haven't re-read the entire posts sequence.
 

Bas

Recovering tool addict
Bas
Corporate Member
I am curious as to why any of you use a house paint on cabinets rather that, pre-cat CV, post-cat CV or some water base lacquer made for wood and cabinet finishing? Is it the cost, availability, lack of knowledge of products, or of spraying those products. I am not trying to be insulting, just curious.
In my case, lack of knowledge. I had no idea you could tint lacquer white. That would have been a much better choice for my project. I was able to spray the ProClassic using my Earlex HVLP 5500, but it took considerable dilution. The result looked OK, but the dilution made the paint completely flat. I ended up topcoating it with poly to get some shine back.

I have since then discovered the joy of pre-cat lacquer. Yes, the fumes are awesome, but it goes on smooth, dries ultra fast, no sanding in between coats (other than smoothing), and you can do three coats in a day.
 

agrieco

anthony
Corporate Member
I am curious as to why any of you use a house paint on cabinets rather that, pre-cat CV, post-cat CV or some water base lacquer made for wood and cabinet finishing? Is it the cost, availability, lack of knowledge of products, or of spraying those products. I am not trying to be insulting, just curious.
For me- it is lack of knowledge.

I’m going to be doing table legs in white soon...will get lots of wear and abuse...can you recommend some reading materials and products for a pre or post cat white tinted lacquer? I’d love to get smarter but a bit of searching leaves me unsure to say the least.
 

golfdad

Co-director of Outreach
Dirk
Corporate Member
SW Pro Classic is not a Latex Enamel it is 100% Acrylic which gets much harder than reg Latex
 

Gofor

Mark
Corporate Member
Back when I got into the coatings discipline (50 years ago), "Enamel" meant an alkyd oil-based coating that dried by oxidation, although baking it produced a harder coating. It would continue to oxidize over time. Then the automotive industry developed an acrylic enamel, which was still oil-based, but was more flexible. About the same time, came polyurethanes (more UV resistance) and epoxies. What has evolved is that the term "enamel" being used for any coating that contains pigments and has a sheen to it when cured. It now may be a water-based acrylic or latex, a true lacquer, alkyd oil-based coating, etc. Best way to tell what it actually is, is to look at the solvents used and recommended for clean-up. Mineral spirits would indicate oxidation cure oil-based; Lacquer thinner indicates it is a evaporation drying lacquer; and water would be a latex/acrylic.
 

Henry W

HenryW
Senior User
.... Can you recommend some reading materials and products for a pre or post cat white tinted lacquer?
Target Coatings has water-borne finishes - including lacquers, pre-cat conversion varnish, varnish, stains, polyurethane, sanding sealer, and shellac; they are mail-order with no local distributors (closest is a place in TN I believe). I have not used their phone line, but they offer phone advice.

Other brands are carried locally; Klingspor's carries General Finishes products (and others), including some water borne products, but I am less familiar with their lineup. A visit to their store or website will tell you more. I am certain they can order products that they may not have in stock. The great thing about a local store is that you can get advice, and Jay the manager at the Raleigh store has lot's of finishing experience.

Not having s separate finishing space, I decided to as much as possible stay away from solvent born spray finishes - the only except I make is that I do use SealCoat shellac (alcohol based).

I have used Target's waterborne shellac, but discovered that it is NOT direct substitute for 'normal' shellac (i.e. it is NOT suitable a top coat the way normal shellac may be, given all the caveats about shellac as a top coat). Water on the Target shellac re-emulsifies the product the way that alcohol re-dissolved normal shellac.

My advice is to find a product range you like (and can tolerate the price) and learn to spray it. For me that is Target's product line, but that is simply what I have used - without trying any of the other brands. No connection to company, no paid endorsements, ... yada yada.

I have Target's black lacquer in house, and you'd be welcome to try a few ounces (so you don't need to buy a quart or gallon only to discover that your spray equipment is unsuitable). I expect it sprays similarly to the white lacquer (which I do not have). I have found their lacquers to be the easy to use (I am relative novice at spray finishing).
 

Hmerkle

Board of Directors, Vice President
Hank
Corporate Member
It might be good to organize another "Spraying workshop"
I have Dirk's (Golfdad) old earlex and know that it will not spray a "Heavy paint" (latex etc.)
I have two cheapo HVLP guns and I struggle with the consistency - I think it is the operator, not the gun.
One time it seems super easy and the next I get spatter (too much paint) or mist (not enough paint)
 

UncleJoe

Joe
User
This worked very well for me, it took several tries to get it right so one I had it dialed in I made detailed notes. I have been able to repeat the results and achieve a flawless finish every time. I am a "serious hobby guy" not a professional.
Earlex 5500 with a 1.5 tip a 2.0 also works well and may be better. I will try that the next time
SW Pro Classic thinned as follows: ( mix exactly)
  • 32 oz paint
  • 4 ounces distilled water
  • 2 oz floetrol
  • 1 teaspoon 90% alcohol (Charles Neal tip. He says the alcohol relaxes the paint and we all know how alchol relaxes us)
A real key is to use a paddle type mixer in a drill and mix for more than 2 minutes. A fellow on one of the other interwebby sites claimed to be customer service from SW and he said the long mixing breaks down the molecules which tend to string like spaghetti (in the microscope) and by stirring more than 2 minutes with a paddle it will atomize better.

On the second coat spray it wet. I like to have the main parts flat if possible. (doors and drawer fronts) I found that if I sprayed it just a bit wetter than I thought was right it looked orange peel at first but this stuff is designed to flow so do not judge it when you first apply. Allow it to flow and in about a half hour the piece looks perfect.

I just examined some cabinets I built for my wife about a year ago and they look great. It sure looks like someone with more talent than I have did them. Most of our guest think that those cabinets are store bought.

Some folks say you don't need floetrol and they may be right. All I know is this worked for me with my equipment.
 

Our Sponsors

LATEST FOR SALE LISTINGS

Top