Thinning Latex for HVLP

[gdoebs]

Hi guys,

I have a Fuji Q4 Pro HVLP system and I'm going to start painting my new kitchen cabinets (poplar and MDF). I hope to use the same paint as I did on the trim in our house, Behr Premium. I know I'll have to thin the paint down but since I've never done this before, I'm not sure where to start. According to my searching online and reading the manual for the Fuji, I should be ok with the needle set that I have (#4). I think I read to thin the paint no more than 25%. But, what does that mean!?! If I wanted a quart to spray would it be 75% paint and 25% water? or 1 quart of paint and 1/4 quart of water? I'm guessing 75% paint and 25% water but I just want to be sure. I'm planning on adding some floetrol too.

I'll also be building a knockdown spray booth. As well as a drying rack that'll go inside the house to dry.

I do have some 4x8 sheets of cardboard to practice on, and some scrap poplar.

Any other tips?

 

[Bas]

I have the Earlex 5000 HVLP. It came with a viscosity measuring gadget. The idea is that whatever finish you have should flow through the opening within x seconds. If it's too slow, then thin it. Does the Fuji have a similar cup? That'll provide a good start. My suggestion is that you thin it no more than 10%. I'd go with 5% water and 5% Floetrol. If you add more (which I was forced to do), you'll need a lot more coats, and the sheen will drastically dull. I sprayed gloss and it came out flat. So if you're on the fence about a sheen, go one glossier. Excessive thinning will also affect the paint adhesion and durability.

As for the paint, make sure you use a 100% acrylic paint. This can be confusing, as many companies call all water-bourne/ water-based paint "latex". If you use paint with actual latex in it, the finish will be soft and remain "tacky". Which means that if you actually put stuff inside your cabinets, they'll stick. I've used Sherwin-Williams Pro Classic with good success. Note that this paint is called "latex" too.

Spraying primer was even harder than spraying paint. I suggest you do that with a brush/ roller, and then sand any brush marks smooth.

 

[BSHuff]

I can agree with everything Bas said. Floetrol and Sherwin Williams Pro Classic. it dries hard and solid. No blocking, and quite durable. I got my settings so I could spray it unthinned w/floetrol and a large needle. Ended up with almost glass smooth finish.

Another thing that helps is if your doors can support it, is to hang a clothes line and put cuphooks on the most invisible side when done and hang the doors by cup hooks on the line. makes it MUCH easier to paint & recoat doors.

 

[petebucy4638]

Hi guys,

I have a Fuji Q4 Pro HVLP system and I'm going to start painting my new kitchen cabinets (poplar and MDF). I hope to use the same paint as I did on the trim in our house, Behr Premium. I know I'll have to thin the paint down but since I've never done this before, I'm not sure where to start. According to my searching online and reading the manual for the Fuji, I should be ok with the needle set that I have (#4). I think I read to thin the paint no more than 25%. But, what does that mean!?! If I wanted a quart to spray would it be 75% paint and 25% water? or 1 quart of paint and 1/4 quart of water? I'm guessing 75% paint and 25% water but I just want to be sure. I'm planning on adding some floetrol too.

I'll also be building a knockdown spray booth. As well as a drying rack that'll go inside the house to dry.

I do have some 4x8 sheets of cardboard to practice on, and some scrap poplar.

Any other tips?

I have a Fuji HVLP as well as a Titan HVLP. Both guns are used primarily to spray high-quality 100% acrylic latex paints. The Fuji was purchases in late 2005. It is a fantastic HVLP system that can be adapted easily to spray a wide range of paint. I use Behr 100% acrylic paints for all of my trim work. The Fuji sprays it right out of the can. Still, I like to add just a little water and make sure that it is well mixes.

Paint is affected greatly by temperature. Humidity can cause you to have to make adjustments too. My suggestion is to do a little experimenting. It should not take long to get a perfect setting.

Pete

 

[pirate71]

I have a fuji and have sprayed only Ben Moore water based paints. I had to thin those paints about 25-33%. The right amount of thinning is determined by the viscosity cup and the manual(which tells you how many seconds it should take for water based paints to flow thru). I used distilled water to minimize any opportunity for rust to develop.

My experience is that water based paints tend to want to run a little more often than oil based paints. For that reason, I painted all my doors in the garage laying down. I used a lazy susan that I got from Woodcraft to spin them around to keep from me having to move. Also, I built a rack to put the doors on for drying. The rack holds about 24 doors. The rack does slow you down some since you have to wait for one side to get dry before spraying the other side. The good thing about it is you can do the backs first to improve your technique. In fact, if you are around Durham, you can borrow my racks.

In the kitchen, I painted the insides of the cabinets by hand and then sprayed the frames.

As far as paint goes, use the best paint you can get for your kitchen. Some latex paints will do better at developing a hard enough suface to withstand oil/grease/grim and the constant cleaning that is needed. Other latex paints may not do so well. I would not worry about the cost since it will only take a gallon of paint and a gallon of primer.

Evans

 

[Bill Clemmons]

Spraying primer was even harder than spraying paint. I suggest you do that with a brush/ roller, and then sand any brush marks smooth.

I've been using Zinsser's B-I-N Primer. It's shellac based and can be used under any topcoat (oil or water based). Thin it a little w/ denatured alcohol and it sprays great w/ HVLP equipment. Drys quick too.

HTH

Bill

 

[Gregory Paolini]

I've sprayed the behr paints before with my HVLP conversion gun - I don't really like to thin Water Based products more than about 10%, so that's all I thined it, using nothing but distilled water.

I swapped out the needle and aircap in my gun though to a 2.2mm, and got great results. I don't remember my pressures or anything, just experiment a bit. But then again, if you're using a turbine, adjusting pressure won;t be an option.

Hope this helps

 

[Howard Acheson]

Water Not a Thinner

>>>> I think I read to thin the paint no more than 25%.

Water, in waterborne finishes in NOT a thinner. The function of water is to keep certain other chemicals in suspension and separated. When applied, the water evaporates and allows these other chemical components to come into contact and to sort of "melt" together (coalesce) into a film that flows out, cures and forms the protective film. Adding water may cause these chemicals to become so far separated that they do not come into contact and begin the coalescing process.

The best answer you can get is contact the tech department of the manufacturer of the finish you plan to use and ask them how much water or other chemical can be added. Unlike traditional oil based finishes, each manufacturer of waterborne finishes has their own mixture and chemicals. Don't assume that a thinning process that works for one finish, will work for others.

Finally, spend some time spraying good sized sample panels to learn how your selected product handles and how it looks when fully dried. No tears.

 

[petebucy4638]

I've been using Zinsser's B-I-N Primer. It's shellac based and can be used under any topcoat (oil or water based). Thin it a little w/ denatured alcohol and it sprays great w/ HVLP equipment. Drys quick too.

HTH

Bill

Zinsser makes a water based primer that sprays great through an HVLP too. The alcohol based product is great for outdoor projects in the winter, it is virtually immune to freezing.

Pete

 

[gdoebs]

Thanks guys! This site rocks.

I do have the viscosity cup to test.
I'm going to give the Zinsser water-based primer and the Behr paint a shot.

I'll post pics of the results...

 

[Alan in Little Washington]

I have a friend in N. VA who does A LOT of paint grade custom kitchen and built-in work. He recently switched to Sherwin Williams acrylic. He shoots it with a Graco airless.

 

[JimD]

There is an article on the website of the woodworking dealer who sells mail order in Atlanta (can't remember the name right now) about thinning latex with Resisthane - a water based clear finish. It makes the paint also more durable. I haven't tried it.

I have a Fuji mini max 3 and the manual says you can spray latex but they think something like a Wagner is better - because of the thinning required.

Jim

 

[petebucy4638]

I have a friend in N. VA who does A LOT of paint grade custom kitchen and built-in work. He recently switched to Sherwin Williams acrylic. He shoots it with a Graco airless.

I have an airless sprayer too that we use in new construction. An airless is faster for painting large areas and with some tuning it can work will with trims. The problem with an airless is that it produces a lot of overspray. An HVLP has very little, sometimes no, overspray. It is an easier gun to manage, especially when putting down thinner coats of paint.

Pete

 

[Alan in Little Washington]

I have an airless sprayer too that we use in new construction. An airless is faster for painting large areas and with some tuning it can work will with trims. The problem with an airless is that it produces a lot of overspray. An HVLP has very little, sometimes no, overspray. It is an easier gun to manage, especially when putting down thinner coats of paint.

Pete

I won't argue that. You should see his paint room/booth! You could remove all the framing lumber and drywall and it would still stand up from all the paint on the walls!! About 60-70% of his commissions are white work so he is really good with the airless.