Showing posts with label HVLP. Show all posts
Showing posts with label HVLP. Show all posts

Thursday, May 9, 2013

Getting Your Spray On: Working on a project

 
With the right equipment and work environment any job is easier!
After spraying 20 plus Tater Tot sculptors, a kitchen cabinet job doesn't seem so scary.  But you don't get all you can drink Diet Cherry Lime Aides either. 
 
In the last two posts, I covered how a HVLP spray system is put together and how to use/trouble shoot the equipment.  Knowing the parts and how they work together can mean the difference between....
 
 
 
Mud Pie
 
or
 
a pie made of mud
 
 
The final part of using a spray system is creating an environment both on the job site (to work on the frames) and off-site (for doors and drawers) that is clean, safe, comfortable, and climate controlled.  I am very lucky to have an industrial spray booth that I use for commission projects and to teach cabinet classes.  Our local finishers have also enjoyed renting it for 8 years now.
 
 

Most people will not have the space for this type of investment and it is the biggest challenge for every cabinet finisher.  The best space is one that has adequate ventilation and climate control.  And usually the two spaces most available are the basement, which has climate control but poor ventilation, or the garage, which has good ventilation but poor climate control.

If you opt for a basement set-up, make sure you have windows that will open and use a fan to circulate air towards the window(s). A garage is easier to get cross ventilation. To keep either area clean and limit air-born debris, you might consider a Zip Wall system which allows you to create a pop-up spray booth.

A water-based system is great because you don't have the build-up of smelly chemicals but you still need to protect your lungs. A paper dust mask is sufficient when spraying most water-based product especially in combination with open doors/window and a fan.




And make sure you have enough air hose length to keep the turbine outside your Zip Wall, spray booth, or small closed rooms like powder bath.  For large areas, such as a kitchen, I keep the turbine 15-20 feet away from where I am spraying.  If you have asthma, talk with your doctor about spraying as a respirator might be recommended.

The ideal climate for spraying is between 65-75 degrees with little to no humidity.  Good luck with that!  It does mean that you have to be aware of the average seasonal climates for you area and the weather guess report for the week.  Working in the home, talk with the homeowner first about setting the thermostat to the appropriate temperature before you start the job.  New construction is harder because some builders are cheap and won't turn on air conditioning or heat.  In the summer I would spray first thing in the morning and in the winter I would spray in the afternoon on new construction sites.

Be careful of using forced heat and air. Your finish may craze (spidery cracks) if you spray in a colder room and then roll your pieces into a room with too much forced air/heat because the very top of the finish is drying too fast.


The two simple things that will make your life much easier spraying at home are:


1) Buy a cake turner or Lazy Susan.  These are also great to use when you are glazing and detailing cabinets.  You have to be careful not to get fingerprints on the back of your piece. And you don't want to touch areas you have just sprayed.  It is better to get the cheap cake turner-the better ones will tilt under the weight of heavy cabinet pieces.

 
 
2) Invest in a racking/drying system.  There are a few companies that make actual cabinet drying systems and these can be particularly useful where climate control is a problem.  In our situation where the room in climate controlled, we use metal racks on wheels from Costco.  The open shelving allows air to circulate and I can easily see drawer fronts to make sure my pieces are matching. The wheels make it easy to move pieces from spray area to dry area.  Racks like this are also easy to label because sometimes you have 2-3 finishes going in a single kitchen. You don't want to paint a door that was supposed to be stained!
 
 I spray my doors laying flat on the cake turner and start by spraying around the sides.
 
 

Remember I am turning the actual cake stand so I don't need to touch the sides of the door.  Then I spray across the top of the door.


If you  spray the top first and then the sides you will be blowing air and product into the area you just sprayed.  The key is to not spray too thick so it pools in the recesses of a door.




Spraying on site is even more worrisome for some people.  Clients are very concerned about over-spray and dust.  Some clients will flat out refuse to let you spray.  You can brush and roll a cabinet frame and spray the door and drawers.  Just plan on taking additional time to keep those frames smooth.



Masking the frames is what takes the longest time when you spray on site.  I like to use a mix of painter's plastic and masking paper with low tack painter's tape.  Always confirm with the client which areas are to be painted/stained and which will be natural wood that only gets clear coat. This has become a popular furniture look for cabinetry.  I mask the floor from the base molding out at least 1 foot and then drop cloth the rest of the floor. Bring clean sheets to drape any furniture that can't be moved from the room.  Always plastic electronics, appliances, vents, and openings to other rooms.
 
Yes it is labor intensive to mask a room but once it is done you can spray a whole kitchen in under 20 minutes.  Your product dries faster, goes further, and you have less sanding.  Plus the extra effort to mask a room lessens that chance you will get paint somewhere it shouldn't be.
 
 
 
 
 
For this job we were working on Birch which is a smooth wood that skews softer then Oak.  Stain blocking is not usually an issue with Birch although it does get fuzzy with the first product layer.  I sprayed the cabinets with water based matte primer from Zinsser and then sprayed a custom taupe silver metallic.
 
Always do a drawer and door from start to finish before you begin a project.  These are your guides for working in your shop and on-site.  I also recommend finishing the frames first. It is a psychological relief to your clients to see progress and get the kitchen unmasked and cleaned up. 
If they are happy with the frames, you can relax while doing the doors and drawers which are the "stars" of a project anyway!
 
 
 
With a little practice and some confidence you will be able to deliver a factory level artistic finish that will keep you ahead of your competition and increase your profit. 
 
 
 
 

 



Thursday, May 2, 2013

Getting Your Spray On Part Two: Using the System

 
 
 
 
FAUX FORCE FOUR...
Fighting for Truth, Justice, and Better Finishes
 
 
(Talented Kansas City Finishers Brenda Macaluso, Kerry Phillips, and Mona Kurtz.)
 
 
 
Ah... the first signs of Spring.  Bruce is dry cleaning his Hawaiian Shirts, the dogs are leaving grass stains on the carpet, and I have monkey palms because I still don't know the right way to apply self tanner.  But most importantly (and to the point of this post) it begins the optimal time for many finishers to use their garage for cabinet/furniture jobs!
 

In Part One, I talked about the basics of a HVLP spray gun and reviewed the parts.  Of course, what you do with those parts is another story....
 
 
 
For example, these are parts to a car
 


 
and depending on how you use them, you end up with a DeLorean
 
 
or this.  Where do you think he put the Flux Capacitor?
 
 
So let's assume that you read the last blog post or your owner's manual and your spray gun is correctly assembled. But you are still having problems getting that fine factory finish you (and the client) are hoping for and the reason you purchased a spray gun in the first place.
 
The first thing to check does involve the parts. Make sure you have the correct sized needle, air nozzle, and air cap for the viscosity of your product. Thicker products such as base coats and crackle medium need a larger numbered set-up. Thinner materials such as topcoats and crackle size require a smaller set-up.  If you match the thinner topcoat needle to a base coat sized air nozzle your product will just stream out the tip.
 
Next, make sure your product is thinned properly.  The beauty of a water-based system is that you can thin your product with tap water.
 
 

The product line I use, Faux Effects, is on the thicker side.  That can be a good thin because thinning with water and spraying gives me more product square footage.  I use Setcoat as my base paint for cabinets and thin it about 1/4 cup of water per quart of Setcoat.  You want it to resemble half & half.
For topcoats, I again start with 1/4 cup water per quart of product.  Topcoat should be the consistency of whole milk.
 
Make sure your topcoats are well mixed by dumping in a separate container to get the solids and liquid well blended.  Just spraying the liquid without the full benefit of the solids will create a shiny surface with spotty coverage.
 
 


After thinning, you need to strain your product. It should flow easily through a medium to small screen.  I usually thin and strain my product beforehand rather then on site when I am spraying on site.  In a pinch, you can make a strainer from folded cheesecloth (or pantyhose if you happen to be wearing them or robbing a convenience store later in the day).

The only products I do not strain are crackle size and crackle medium.  For the size, I thin 10% with water and use the topcoat setup.  For the crackle medium I thin to paint thickness and use the basecoat (larger) setup. If you strain these products you will end up spraying tinted water and nothing will crack.


Put some petroleum jelly around the gasket in the spray gun lid-this will improve the seal.  Getting the lid tight and straight are two different things. You should feel a click if your lid is on properly.  If product is bubbling around the lid then the top is not on straight even if it is tight.


Attach the gun to the air hose and make sure the hose is open. In the picture above the air hose lever is in the open position.   In the picture below, the air hose lever is closed. You should hear the turbine strain.




This lever is a great way to control air speed-especially working off a ladder or scaffold.  By adjusting the lever I can slow my speed which reduces over-spray and increase precision.


In the picture above, the needle is even with the air nozzle and air cap opening. This is the "normal" setting for covering a cabinet door with some overspray and is a good setting for a spray booth situation.  The air cap in the above picture is set on the diagonal which means my spray pattern will be an elliptical:


I use this setting for corners, dental molding, and when I spray heavy material like crackle medium.
The air cap is usually turned for horizontal or vertical spray directions. This is one of  two adjustments you may make with this set-up to control over spray and spray direction.  The other adjustment is made with the black ring on the front of the gun.

By turning the black ring (seen below), the needle either moves out further or retreats back.  The further out the needle is, the larger the spray. You cover more area fast but you also get more over-spray.





For less over-spray and precise spraying, rotate the black ring counter-clockwise and the needle retracts (picture above).  This also means that covering an area will go slower. My air cap is turned to a horizontal pattern.

The biggest concern most people have is spraying in the home. But, with a little practice and the right settings, you can control the overspray!




 In the picture above I've used 9"masking paper around my door. The door covers 2"inches of the paper.  I retract my needle to even or less then the air cap.  And I barely turn my air hose lever to reduce the airspeed. 
 


Hold the gun about 6 inches from the surface, compress the trigger, and slowly follow the rails and stiles of the door.  Going slow will give you better coverage and minimize drips.  Don't bring the gun in closer as you move across the surface. The movement is fluid-not a windshield wiper.  Release the trigger when you get to the end of an area.


When I want to spray the vertical sides, I only need to turn the air cap to the vertical position:

And here is my door:


And here is my over-spray on the top:



And on the side:


To show you how easy this is, I sprayed the door with my right hand and took the pictures with my left hand while I was spraying.


This is sprayed topcoat on black so you may see it.  My needle is slightly out compared to the nozzle (rather then even or recessed) and the air cap is set in the vertical.


Common Problems and Solutions:

The product is spitting out of the gun. First check that the air hose lever is open. Next, with turbine off, remove the lid and make sure the air spout at the top is not clogged using a paper clip or spray gun cleaning kit.  If both things are fine then your product is not thin enough.  Add more water and stir into your cup.


The product is running down the surface.  Product may be too thin.  Also you may be spraying too heavy-tighten the back ring setting on the needle. This will make the trigger harder to pull all the way back.



There are bubbles or rings on the surface.  This is a fish eye.  Usually it means there is a containment on the surface or in the product.  I only spray water-based products in my gun and make sure any cleaners such as Latex Lift-off or Lacquer Thinner are thoroughly removed.  If on the door, rinse or wipe the finish off.  Clean and re-sand the door.

The finish is dimpled.  You are standing too close.  Setcoat actually lays out really well even with a few dimples.

The finish is spraying unevenly.  Make sure that the all the air cap holes are clean.

There are 3 holes in this set-up including tiny ones on either side of the air nozzles.  See that gold bracket on the side? It attaches to the gun air tube and needs to be cleaned as well.


The topcoat is drying white in the corners.  This is from spraying too heavy and the product settling in the corners of the door.  It is always better to spray multiple thin coats (following 2nd coat instructions based on product) rather then one thick coat. The other reason for this has nothing to do with spraying.  You need to put a gloss topcoat on a dark finish. When the gloss dries, you may apply a satin, matte, or dull finish.

The best thing you can do is practice. I have sprayed bed frames with the mattress on, closet doors with clothes in them, and crown molding on a curved staircase next to a freshly painted ceiling.

All it takes is confidence, good plastic/paper masking skills, and a client out of town.

In the final installment, we will cover how to set up for a real spray job both in your studio and on the job site.





 
 

Wednesday, April 17, 2013

Getting Your Spray On Part One: The Parts

 
 
 
 
Spray Guns don't harm cabinets...Bad finishers do!
 
 

Wouldn't all those Charlie's Angels poses done at Girl's Night, Bachelorette and Wedding Parties be way more interesting if they were holding spray guns?

After 16 years of a cabinetry business and 10 years of teaching cabinetry, the only thing that gets people's hands to really shake is the thought of using a spray system.  Unfortunately this fear keeps many from enjoying an easy way to deliver a higher quality finish, save on product, and spend less time hand painting and sanding.  With the right instruction and a spray system that you feel comfortable with, anyone can produce factory finished furniture grade cabinets...or spray tans.


(Warner Bros.)
 
 
Obviously not done by a trained professional-probably a pageant mom with a paint roller.
 
 
 
I use a HVLP system which means High Volume/Low Pressure Sprayer.  This is different then an airless system which uses a compressor.  Each system has pluses and minuses and it really depends on what and how you spray.  If you have a commission business that involves lots of wall and trim painting then an airless system is a fast way to cover a lot of surface.  It also helps to have a large space with good ventilation to spray.  Because you may run tubing to the compressor and separate tubing to your paint, you can work with large amounts of paint or topcoats which saves time having to fill a gun.  Of course there are several cup guns that will also work with a compressor.
 
A big concern for the faux finisher that wants to spray cabinets is controlling the process. Meaning they want to direct the product with the least amount of over spray or drips. This is where a HVLP system can be a more manageable choice.  HVLP sprays high volume at pressure that is generally less then 10 pounds per square inch compared to 80-90 pounds in a traditional set-up.  Your transfer efficiency is higher at 65%-90%.  But, in general, you have to go slower and refill your cup gun more often.  You may also need more coats because you have to thin the product you are spraying.
 
Most HVLP spray systems work the same-the difference is in the details and the price.  I've seen cheap systems that work OK and very expensive ones that are too much machine and not user friendly.  I am so picky about what I want in a gun after all these years, Bruce had a system built for me so I would stop coming home with dented cup guns...because I had thrown it. That is the system I sell at Surfaces. There is nothing wrong with other systems and this blog will give you good info regardless of  what brand/type you have. Just make sure that wherever you buy can give you tech support and replacement parts (a problem with buying used systems sometimes).
 

 
And yes a spray system is an investment.  But it is one that will pay for itself in one cabinet job.
 
 
 
 
 
Many finishers like a turbine system that is compact and easy to carry or place on scaffolding. The turbine is the motor/fan assembly and comes in different stages. Stages indicate the number of fans.  More fans mean more stages which equals increased airflow and increased airflow in the gun.  A 2stage-4stage is usually enough power for most faux finishers. My system is a 3-stage.  Just enough to spray heavier products like crackle while still maintaining an airspeed I can control in a home.
 
My system has no speed control-I control it with the lever on the hose.  Other systems have a dial where you can control the speed from 1-10.  I lessen my speed when I am precision spraying a piece such as a table base and want as little over spray as possible. 
 
The turbine is about as loud as a vacuum cleaner.  The tubing length should allow you to move easily around a room and to place the turbine outside of small rooms such as powder rooms while you spray.
 

The above gun is a siphon gun-it sucks.  No really, that is not a judgment call, that is how to works. The advantage to this cup gun is it tends to be larger and hold more product-you have to refill it less.  Some people find having the cup underneath makes it easier to see what they are working on. Others find it heavy on the wrist. 


This is a gravity feed cup gun-it blows.  Literally the air blows down from the top.  In my usage a gravity feed cup gun clogs less with thicker product because gravity is working with you.  Plus the smaller size fatigues my hand/wrist less.  You do have to refill this size of gun more often. It holds a quart of product and I can spray about 25-30 pieces with a single coat of thinned product before refilling the gun.

The above gun is metal but you can also get them in plastic.

The plastic gun is a little bit lighter and does allow you to see your product as you are spraying giving an indication of when you are running low.  The lid of this particular gun is easy to screw on but the hole at the top that allows air to enter the cup could be a little larger.

One of the things to look for in a gun is the exposure of the fluid needle.  In both the siphon gun and the plastic gun, the fluid needle can be seen between the trigger and the air cap.




 
 
In the second gun, I've removed the fluid needle so you can see the gap.  Again there is nothing wrong with the design but this is a place where people have leaks.  Make sure your needle is fully engaged before loading your product. The upper gun needle loads from the back while the lower gun needle loads from the front.  For the lower gun I place the needle in and then gently press the needle against a solid surface to make the needle fully clicks into place.  When you pull the trigger, you should see the needle move.
 

The gun I use the most has the needle loaded in the back and is fully enclosed in the gun barrel. There is no leaking between the trigger and the fluid needle.


Above are the gun parts that stay the same regardless of what you are spraying.  Below are the parts that change based on the thickness of what you spray:
 
 

Start with selecting you Fluid Needle.  The larger needle is for thicker products such as basecoat. The thinner needle is for thinner products such as topcoats.  I keep it simple with 2 sizes. 2.4 for basecoats and 1.4 for topcoats.
 
Next is the fluid tip which I like to call the nozzles (it just sounds fun).  As you can see the hole size is different.  The larger hole is for thicker material and the thinner hole is for thinner material. The sides are marked with 2.4 or 1.4 like the needles but you would have to wear these to see it:

 
 (Warner Bros.)
 
Actually I got a pair when I turned 45
 
 
These are the parts that need to match:
 

This fluid needle, fluid tip and air cap are marked 2.4 and are for basecoats/thicker materials.  In other set-ups this is marked as 6.



The above set-up of for a topcoat or thinner products like crackle size. It is marked 1.4 or a 3 in some systems.

Putting a gun together is easy because the parts makes sense once you know what they do.  The fluid needle should be put together like a pogo stick:

 
I had one of these as a kid-the fact that this one looks like a crutch
 is more accurate then most parents know.
 

Pogo stick! The spring should bounce the spacer up and down if assembled correctly. This is what moves the fluid needle back and force when your compress the spray gun trigger.

If your set-up has the spring above the spacer then your needle won't move when the trigger is pulled.


For this spray system, the needle with the spring and spacer is loaded into the gun from the back.  It is held in place by the fluid adjustment screw:



This has a larger spring.  If this spring is left out, your needle will not engage fully and product will just spill out the front of your gun.  The black screw and the gold piece work independent of one another.  The black piece may be screwed out further to allow the trigger to be pulled lighter which allows more product to come out.  If the black piece is tighter then the trigger is harder to pull and less product comes out.  The gold nut is tightened to secure the setting.


The back of the gun is ready to go with the fluid adjustment screw set at a Quarter width.  Next, you have to set-up the front.  The needle should be sticking out the front.




Select the right sized fluid tip and hand screw it over the needle.  This set-up comes with a weird looking tool-it is used to tighten the fluid tip. There is another spring (the largest) to drop in.
This works with the Air Cap.





 

Next is the disc that gives you the ability to turn your Air Cap.  I call it the Egg Poacher because you want the dimples in it facing down-like you are poaching eggs.

The dimples (for your eggs) fit the bumps on the under-side of the air cap.  When these are put together correctly you can turn your air cap to spray vertically, horizontally, or an the elliptical.

The Air Cap is placed on next-remember it is also marked with a size based on what you are spraying.

Then a black ring is placed over the air cap to hold it in place. By tightening or loosening this ring you control how far the fluid tip pokes out of the air cap hole. 



Now our gun is ready to spray. Next time I will show you how to make adjustments with the spray gun and simple troubleshooting solutions.

And maybe my nails will look a little better in the next set of pictures.