Woodfinishers Weblog

Wood finishing forum for professional finishers

The Kremlin Air Assisted Airless Spray gun video demonstration

This  is a phenomenal spray gun that I have previously not paid enough attention to.  The great benefit of this tool is the increased transfer efficiency or percentage of materials which are making it to the target. With conventional airless you have about a 60% efficiency meaning that you have lost as much as 40% of your paint to the atmosphere and or your spray booth filters. With the Air-assisted airless the transfer efficiency is about 85 % so you are wasting  25% less of your paint.  This  would mean that for every 100 dollar pail of lacquer you are buying  you are saving  about 20 to 25 dollars. That is a savings that can quickly add up and pay for the rig.

In-essence it is pumping the paint out with an airless pump but it uses two opposing  streams of air to atomize the paint  much like a cup or gravity feed spray gun. With the combination of the air,  less pressure is needed to get the paint out and so more of your paint goes on the thing you are painting and less of your paint bounces off the surface and into the air.

The other benefit is that is applies the materials with less force and so give you a smoother finish, in the following video Jody Toole has been using an airless sprayer but was having some troubles with bubbling on the first coat, this was being caused by too much pressure resulting in the materials foaming when they impacted with the surface of the panel. he solved this by backing down the pressure and holding his gun further away, while that solved the bubbling it gave and even lower transfer efficiency and the material did not flow out as well. With the Kremlin all these issues were resolved.

The cost of the whole rig is about 2700 bucks and that is a little pricy but depending on how muc you spray you’ll have paid for it in savings on materials, which by the way are getting  more expensive by the day with rising gas prices.

For note: Jody is spraying the CIC low VOC acrylic lacquer which is, in essence a cab acrylic on steroids  for those of you that may have used such a thing in the past,  it is 160 gr/lt. VOC,  it is low odor and it won’t yellow.  This is the same product featured elsewhere on the blog that the Church of Scientology’s new Los Angeles and Pasadena church furniture are coated in.

 

I sell the Kremlin so if you are in my neighborhood call me and we can get together for a demo if not you can look them up on-line and find the nearest dealer. There are other companies that have air assisted air less equipment as well.

Since this article Jody has gone off and done a few more video demos and so I though I would add them to this posting  so that you could see some other demonstrations of the rig.


 

I welcome your comments.

best,

Greg Saunders
Annex Paint

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April 12, 2011 Posted by | Acrylic Lacquer, Spray techniques, Tips and Tricks | , , , , , , | 12 Comments

How you apply lacquer to plastic or glass

Lacquer Plastic and or Glass ?? How would you do that?

Simple, use and adhesion promoter, and what is an adhesion promoter you ask. This is a product that has been around the automotive paint industry for sometime, It has made it’s rise to fame in the auto industry with the advent of the rubber bumper. Painting rubber bumpers is a trick as you need something that is going to stick to the plastic be pliable and then match the paint job on the car.  

 That being said the makers of the water based conversion varnish have come up with and excellent adhesion promoter, called “Mustang” The automotive guys seem to love it and I was of the mind that I wouldn’t have that much use for it but Low and behold I has a custom cabinet shop come to me with a unique problem.

Their customer ordered high end cabinetry from Italy and made a mistake on the color so they need the color changed, OK no problem, good work for some finisher but wait the doors are a thermal foil vinyl coating. What do you do? Yup, Use the Mustang adhesion promoter. 

 Two coats sprayed on from an aerosol can let them dry for a few minutes and the lay on your coatings, in this case I was spraying the centurion water based conversion varnish as you can see in this picture.

the use of adhesion promoters for painting plastic and glass

As you can see there is a profile in the panel making sanding all but impossible despite that the paint stuck like glue.  I built this up with light coats but it only took my three light coats to do what you seen here. I used a 1.7 mm siphon feed gun with about 30 psi of pressure, just enough to get the materials to atomize.

 Once the coating was dried if wouldn’t lift or peel. I was able to scrap it off with a knife and even with that it didn’t peel.

 The Mustang and the Centurion water based conversion coating are available from my store as well as will be available on line at  http://annexpaint.com web site soon.

 Greg Saunders
Annex Paint

July 7, 2010 Posted by | CIC Centurion, water based Conversion Varnish, From the Chemist, Spray techniques, Tips and Tricks, Uncategorized, Water based Lacquers, Wood finishing | , | 3 Comments

Sucess story using the Rexcell water based conversion varnish

Walnut Kitchen Island finished with W/B Conversion Varnish

 This is a story from  a gentleman who is a retired air force officer whose hobby is cabinet and furniture building, As you’ll see he is an incredible cabinet builder.

 As his shop is in his garage with limmetted space and no spray booth Dennis was interested in water born products but needed something that was super tough. I suggested the Rexcell  Water based Conversion varnish. As you will see it turn out stunningly beautiful.

Fore note: this product is no longer manufactured by Rexcell but is now being manufactured to spec by another American manufacturing company, the product is as good or better than before, It has been referred to as three different manufactures Renner, Rexcell and now CIC. It is all the same product, a water born Conversion Varnish.

Here’s is the Story Dirrect from Dennis : 

FIRST EXPERIENCE WITH WATER BASED FINISH

 I have been building wooden furniture and cabinets as a hobbyist for over forty years. Over this period I have sprayed, brushed and wiped on all the standard finishes that hobbyist woodworkers usually use. Because I’m in my upper sixties in age, I have looked upon the new water based finishes for wood with skepticism. I recently finished a kitchen island for my daughter’s new kitchen. It’s a walnut cabinet with a maple butcher block top. It measures 50 inches long by 30 inches wide by 36 inches high. And, I sprayed a water based conversion coating (called water based lacquer) for the protective finish. This was my first experience with a water based coating and I’m extremely pleased with the way it turned out. I chose it for it’s touted durability which was demonstrated to me by Greg Saunders, a sales representative for the Annex Company of Reseda, California. Greg showed me samples, coated with the product I used, that he placed in his home shower for approximately two months and the durability was impressive. ( You can see this test in another post on the Blog)

 The material I used is made by the Rexcel Company, and is a water based conversion varnish, meaning that it is tough enough for counter tops and moisture resistant for high moisture areas)

I used a Goldenstar HVLP air spray gun (Advertised as being especially for water based finishes)

( This is an inexpensive but quality spray gun that Annex paint sells)

Fluid orifice: 1.7mm (this size is recommended for this water based product)

Pressure required: 15-50 psi (I used 30 psi)

 I was spraying in 90 degree summer weather and therefore added 3 percent of regular lacquer retarder. Greg, the sales rep, said I could thin the product with water by about 10 percent but I used it full strength and it seemed to spray very well. I am used to spraying regular nitro cellulose lacquer and I used the very same technique with this water based lacquer. It appears milky in color when it first goes on but otherwise it sprays on like regular lacquer. You have to use the same caution on vertical surfaces as with regular lacquer. A good technique is to use a big piece of brown cardboard to adjust your spray volume and pattern before tackling your project.

 I sprayed three coats and sanded lightly between coats. I probably could have gotten by with only two coats. Remember, each coat of this water based finish lies on top of the previous coat. It doesn’t melt into the previous coat as with regular lacquer. As with regular lacquer, this product dries quickly and can be sanded within 20 minutes and recoated. It was hot and dry when I sprayed so weather conditions might alter the drying times. After the third coat, it was a bit too glossy for my preference so I waxed with a steel wool pad which resulted in a soft sheen that I was looking for. I’m totally happy with the way it turned out.

 I kept a bucket of water and a rag nearby while I was spraying. A couple of times when I got runs, I immediately wiped it off, let it dry, sanded lightly, and recoated. I really enjoyed the water clean up – of the runs and the clean-up of the spray equipment. A word here about clean-up – and this attests to the durability — if you wait until this finish dries, you can’t clean up with water – it takes acetone. I sprayed the first coat with my regular glasses on (plastic lenses). I got overspray on my glasses and I still haven’t gotten it off. However, acetone on my plastic lenses would probably not be smart.

 I made a silverware tray at the last-minute for one of the cabinet drawers and I brushed on two coats of finish with a foam brush. That went on very nicely too. Will I continue to use water based finishes? — definitely yes, especially for kitchen and bathroom furniture. Will I use it for living room furniture? – the jury is out, but I’m hoping to.   

Here is another picture of Dennis’ work. For note this stunningly beautiful Kitchen Island was built by Dennis for his daughter who recently returned from active service in the Military in Iraq.

Walnut cabinet finished with Rexcell water based conversion Varnish

 For his privacy, I have left out Dennis’s contact informations, However, you are welcome to comment on his work and ask any questions on this blog. If you are intersted in contacting Denis for custom work please send me an e-mail and I’ll foreward it on to him.

 As always if you have finnishing qustions you can leave me a comment here on the Blog or write to me dirrectly at : greg@annexpaint.com

February 12, 2010 Posted by | CIC Centurion, water based Conversion Varnish, Conversion varnish, Tips and Tricks, Water based Lacquers | , , , , , , | 2 Comments

I’m new to the Finishing Game and have questions

The following are a few questions sent into me by a new finisher  I am posting with his permission.

Hi Greg

I am new to this spraying game and wondered if you could let me know what flash off means, also I’m using Sayerlack Hydroplus: waterborne clear self-sealer and so far so good, the finish is great, though i am working in a cold barn with a home made spraying booth and even though I have extraction and filters I am finding particles on the finish. Also what is a good grit to sand in between lacquer coats?

Hi Loukas,
Ok, the term “flash off” is the term referring to the solvents evaporating generally used in reference to solvent based coatings but does in fact apply to water based materials, the solvent being water.

There is the first period after you have sprayed something; its wet, and the solvents are evaporating, i.e. its drying. After that point the coating continues to dry but at a much slower rate. That first stage is the time the solvents are “flashing off”. After that point it might be dry to the touch but still soft. In essence the top layer of the coating has dried but the deeper layers are still drying. Most all coatings dry from the top down unless they are epoxies and urethanes that dry internally with a chemical reaction caused by mixing a part A and B.

Water base materials generally dry slower than solvent based materials but will dry even slower in cold or humid conditions. To speed things up you do two things; heat your materials and or heat your spray area. As you are using water base materials you don’t need to worry about having explosion proof heating (which is something you do have to have when spraying solvent based lacquers.) heat and low humidity with air flow will dry your work faster. That it is drying so slowly makes it more susceptible to dust landing in the still wet finish.

You can also heat your lacquer. For one, don’t store it on the cold concrete floor over night. Minimally keep it off the ground. Warm it up before using it by sticking your gallon pail in a tub of hot water. Or wrap a heating blanket around the can. There are more expensive fluid heaters that heat the liquids as they are going through the hoses to the Gun, Those things are for the pro shop that you aren’t going to need for a while (you can look up fluid heaters or pail heaters on sites like Grangers, Northern tools, and Mc Masters-Carr)

 Just getting your water based materials above room temperature is gong to make a significant difference in the flow out and drying time of you work. Cranking it up to about 98 degrees and you’ll see a finish like glass. When you start heating up the materials that much however you need to have the ambient air temperature and the work piece temperature relatively high other wise your hot materials are going to start pulling moisture out of the air and that will cause you finish to have a slightly milky appearance, which in essence is moisture trapped inside the coating.

Ok the next question: what grit sand paper should you use in-between coats, good question. I use 220 silicone carbide paper 220 is the grit you need much higher than that and you are wasting your time. the silicone carbide is a great paper as the tiny little particles that make up the sand in the sand paper break down evenly so you get and even scratch. There are other fancier papers, Abernete and garnet some people thing there the best others don’t. The other thing you can use is a scotch bright pad there are several different brands 3M makes a few and Mirca (another abrasives company makes a few)

Hope that helps, send me some picture of your operation in exchange for the free advice I would love to hear how it all turn out.

I’m going to post these conversations for others to view, if that’s ok with you.

Best of luck,

Greg Saunders

ANNEX PAINT

818-439-9297

 

 

 

November 25, 2009 Posted by | Finishing failures and the fix, Tips and Tricks, Water based Lacquers | 3 Comments

Is Rexcel Water based conversion coating flammable ?

I had a contractor ask  me the question is the conversion coating flammable as he was going to finish a wine cellar in a basement where there was a gas burning furnace. Normally when spraying lacquers on a job site you want to make sure that all open flames are extinguished Vapors sometimes being heaver then air can sprayed along the ground to a gas burning water heater and go boom –not good. Matt the contractor wanted to find a water based material that would not have this problem and was interested in the Rexcel conversion coating  the following is my response …

“The materials are not flammable However, they are potentially combustible, you should always spray in an area that is properly ventilated and I would, if at all possible turn off the furnace while spraying. Inert dust, such as saw dust or even flower can become explosive all by itself if there is a sufficient quantity of in suspended in the air. Like wise with a sealed room full of over spray and vapor.

The Rexcel conversion coating is water based but it does have volatile chemicals in it.  If for some reason you can’t turn off the furnace then ventilate the room so that your fumes are being sucked out of the room and not into the furnace.”

All that being said I doubt you would have a problem, but I don’t want to be the on that gets you blown up. What I have done personally in the past when confronted with such situations is to erect a temporary spay booth around the work with Plastic and 2X2s or something similar. Tape it to the ceiling and floor, Home depot sells zippers that you can tape on to the plastic and use as an entry and exit.  Then I would duct in (either with plastic or flex dusting you can also find at home depot) and air supply and an exhaust, I have built some pretty spiffy spray booths in some real swanky homes where the customers did not want to spell lacquers. You can put a A/C air filter on the exhaust side to catch particles before it goes out a window.   

 Let me know if that is helpful.

Greg Saunders

ANNEX PAINT

November 12, 2009 Posted by | CIC Centurion, water based Conversion Varnish, Conversion varnish, Tips and Tricks, Water based Lacquers | , , , , , | 1 Comment

Renner Acrylic lacquer -Tips for scuccess

 

This is a brief write-up from a finisher who has been successfuly using the Renner Low VOC Acrylic Lacquer

Dear Greg,

 As you requested I’m giving you a little write up on the Renner Low VOC Acrylic lacquer from that you have been supplying to me.

 I have been using the Renner Lacquer and really like this product.

 I wanted to detail some of the basic procedural points I employ when using this product that may help other people who use it:

  

  • I generally only need 2-3 coats of the Renner to get a beautiful finish. 2 coats are most common if you don’t thin the product. The product does not need to be thinned. I have thinned the Renner Acrylic lacquer but only on the final coat if you don’t wish to have any further build up than what I already have on the piece I am spraying. You shouldn’t this this any  more than about 5% per manufacture’s specs any way.

 

  • The key to spraying a good finish is having your gun set properly based on your spraying conditions ( mainly temperature and size and shape of the item you are spraying .) I generally have the PSI on my gun set between 20-40 no more than 40 psi. Then watch your spray in reflected light as you are spraying to ensure you have a wet coat over your whole job.

 

  • I have found that the Flattening agent in the Renner Lacquer tends to settle rapidly to the bottom of the can or spray gun. I have picked up a gun that I had sitting with the renner Acrylic lacquer in it for a few hours and sprayed it and the first thing that comes out is the white flattening past that has settled to the bottom of the cup. A light sand and then re-spray with the same product handled that for me. I have also had spots of white spit out of the gun these are just the flattening past that settled. You have to let the lacquer dry and then sand then off and re- shoot it. The over all handling is to stir and strain the materials well and then don’t let your gun sit for too long. If you use a pot system then stir the pot regularly. Shaking the materials well before you use them is also a good Idea. The flattening past goes back into solution very easily.  

 

  • I always test spray something before I lay on a coat and especially the final coat; I want toknow that the gun and materials are all dialed in before lay the materials on the final coat.

 

Hope this is helpful.

Tia D

 Tia has worked in a custom mill that produces a wide Varity of custom mill work that has been shipped and installed around the world. She has been applying high end finishes for about 4 years and is one of the best and most detail oriented people in the trade. I asked here for this little write up to help other customers with this product.  

  In addition to Tia’s Tips I wanted to add a few other characteristics about this material that I have found about it.

  •  This is an acrylic lacquer, the qualities of it are that it doesn’t yellow and it is nearly as hard as a Catalyzed lacquer, however, you can’t mix it with regular nitrocellulose lacquers. You have to keep these materials separate and do not mix them.
  •  You also don’t want to use this material over another lacquer it is self sealing and is used with it’s self spray in a light coat and lat that flash off and then your following coats to the desired build. You can glaze between coats.

 

If you have questions or comments send me a line I’m always interested in hearing what people are running in to.

 Best,

 Greg Saunders

Annex Sales Rep

greg@annexpaint.com

July 1, 2009 Posted by | Acrylic Lacquer, Finishing failures and the fix, Spray techniques, Tips and Tricks | , , , , , , , | 2 Comments

Questions about about what wood finishing product to use and where

I thought I would post an Email that was sent to me with a very valid question. Water Based polyurethanes versus Solvent conversion Varnish. Which is harder which is better?

 

Hello,

 I am in the process of building some pantry cabinets for my shore house.  I want to achieve a nice solid white finish. What would you recommend. I was thinking a white tinted conversion varnish applied w/ a hvlp conversion gun. Any other suggestions. I just need it to be more durable than paint. My other option was to paint then apply a waterborne polyurethane coating.

MR B.

Here is my response and answer to the question

 

Hi Mr. B,

 

You have several options. But what I would recommend is the water born poly or similar product. The conversion vanish is great stuff but is very tough on both the people who spray it and your equipment. The acid catalysis is rough on a body, if you do use it get a spray suit with a hood and wear a respirator. It does produce an incredible finish and fast. On the up side to the conversion varnish it is slightly clearer, but you are not doing a clear over a wood stain so that wouldn’t be a significant issue.

 

The down sides to the waterborne poly is it is a little trickier to spray and requires a larger tip size usually 1.7mm or bigger and you may need to experiment around first to get it to lay down smoothly, you may require a certain amount of retarder so that it will lay out smoothly, 3% is all you would want to add after that it will take forever to dry and will compromise the hardness. Once you have your solution dialed in its pretty simple.

 

I would get a good white primer on first otherwise you will be putting on more coats of the poly that you really need and they are harder to sand. Ellis 1262 water based white primer is a great one. Ellis is however a La company I don’t know where you are. Dunn Edwards and Sherman Williams both make decent primers; a good primer will save you time and money. Get the surface as smooth as you can with the primer then two top coats and you are done.

 

Don’t get a water based poly from Home depot or Lowes the “Minwax” polyurethane they sell isn’t that good and doesn’t do that well. I would get something used by professionals, Renner is what I sell  and I love the stuff this is an Italian manufactured material. Of course there are others that are very good as well. “General Finishes” have a few.

 

I have an incredible product that I really like that is somewhere in-between a water based poly and a Conversion varnish. It is manufactured especially for us by a company called Rexcel I have mention of it on my Blog. If you go to the Blog you can see the Rexcel listings I have there as well as the test I am running with the material. I have three panels I shot my self that are in my shower getting wet daily. So far they have been there a month and show no signs of water damage.  

 

 

  Anyway, that product is interior/exterior and harder than hell, you can also buff it to a mirror finish and is only about 54 bucks a gallon if you are interested in having some shipped. We can do that.  We have it white I believe, the one thing about white is there are several whites so you might want to do some testing first. You can also send us a color sample and we can match it. If you do that you have to provide a board with the color of your choosing that is at least 6”X6” that way we’ll have some thing to work with.

 

 

 Let me know what you decide and how it all comes out. If you are interested send some pictures with a little write up and I’ll post it on the Blog.  There is currently one posting from a guy that did his own kitchen with a water base lacquer and it turned out great. You should read that one as well as there are a few tips in there that are Key. One of which is the fact that all water base materials take longer to dry and longer to Cure. You have to let them cure for a few weeks before they get really hard. You can install them after a day or two but be very gentle with it for at least a week. The Conversion Varnish goes hard with a chemical reaction and will continue to cure for days and weeks but will get harder faster than the water based materials that cure at the rate of water evaporating. That by the way is determined by temperature and relative humidity. You can force dry then with heat and air flow but don’t cook them.

 

 

You got me on a roll here, did I answer your sufficiently?

 

Greg Saunders

ANNEX PAINT

818-439-9297

 

 

 

 

March 7, 2009 Posted by | Conversion varnish, polyurethane, Tips and Tricks, Water based Lacquers, Wood finishing | , , , , , , , | 1 Comment

Spray Finishing Basics

Spray Finishing Basics

by

Thomas Craven

 

All spray systems attempt to achieve one thing, that is atomization. Atomization from the dictionary is to, “reduce to minute particles or to a fine spray”. Whether you chose conventional, HVLP, or airless spray equipment, they all achieve the same thing; that is atomization. A satisfactory finish is produced when the spray material is atomized to the point that the material will flow onto the surface and become a uniform and even coating.

 

Viscosity and pressurization are the two main factors that effect proper atomization. 

 

I looked up the definition of viscosity in the dictionary and found it to be just as hard to understand as the name itself. So I will tell you my definition of viscosity as it relates to spray finishing. Are you ready for it; it’s how thin the material is! Correct atomization occurs when the material being sprayed is just viscous or thin enough that the pressurization provided by the spray equipment in use can break up or vaporize the particles to produce a satisfactory coating. You only thin the material down enough so that your spray equipment will atomize the material while producing a coating that flows out onto the surface. Thinning the material too much will leave a coating that is spotty and runs down vertical surfaces. A coating too thick that is drying to fast will give you dry, rough areas and orange peel.

 

Now that we have our material correctly thinned how do we then atomize it? By pressurization. It is the air under pressure coming out of the front of an air gun that breaks up

 the material. Or in the case of airless spray equipment, it is the pressurization of the material itself in the spray line that is then forced out the front of the gun through a very small orifice or spray tip that causes atomization at the front of the gun.  

 

Spray Equipment

 

Conventional– High-Pressure, Low-Volume air spraying is out dated technology. Rarely in use in California any more. Produces a lot of overspray and hence wasted material. Material is presented at the front of the gun where air ports in the air cap at the front of the gun introduce a low volume but high pressure, (40 – 60 psi.), stream of air into the material to break it up and create a variable fan pattern.

  

HVLP– High-Volume, Low-Pressure, is the standard equipment in use today in California. It atomizes the material in the same manner as the conventional gun, by introducing a stream of air into the material that is presented to the front of the gun. However HVLP guns use a larger volume of air at a lower pressure typically 10-20 psi. Reversing the relationship between pressure and volume. This system decreases voluminous overspray and saves materials.

 

Compressors and Filters. Both of these spray systems need compressed air to operate. This air should be filtered as the action of compressing the air heats it up. While in the tank and hose, this air cools down. The moisture in the air then condenses in the tank and lines. In addition compressors will inject oil and other contaminants into the air supply. An oil and water separator / filter mounted close to the end of the airline is recommended. The compressor should be installed outside the building whenever possible. Remember it will be drawing air from the surrounding area you install it in and blowing it on your work. 

 

Spray cups / guns and spray pots.

 

A siphon cup gun has a one-quart cup attached to the bottom of the gun. When you pull the trigger on the gun, air is released out of the air ports in the cap at the front of the gun. This air stream siphons / pulls material out of the cup. The vent hole at the top of the cup must remain free and clear to allow air to enter the cup so that the siphoning action can take place.

 

A gravity feed cup gun is a new innovation in cup / gun design. The cup is mounted above the gun so that the force of gravity is used to bring the material down and present it at the front of the gun. You must keep the vent hole at the top of the cup free and clear to allow the material to drain into the gun. It is superior to the siphon feed cup gun design. Both siphon and gravity feed cup guns are best used for small amounts of material. Sample work, shading and toning procedures, etc.

 

A spray pot is a two-gallon or sometimes five-gallon pot or bucket that has a pressure regulator attached to the top of it. The regulator allows air to free flow through to the gun to atomize the material, but it also pressurizes the material in the pot. Instead of passively siphoning or allowing gravity to feed the material to the front of the gun, the spray pot will deliver material under pressure to the front of the gun for atomization to take place. This will allow greater production as less air is needed to atomize more material. In addition greater capacity is provided by the two or five gallon quantity of material in the pot.

 

Airless spray machines use a hydraulic pump to pressurize the material that is sucked up in a pick up tube from a five-gallon bucket. The material travels in a ½” diameter spray line that are available in fifty foot lengths. The material is forced out the front of the gun through a very small orifice or spray tip. This spray tip atomizes the material and shapes it into a spray fan of preset widths 3 to 21 inches wide.

 

 

The big advantages to airless spraying are,1. Dispensing with the need for compressed air to atomize the material. You get straight material coming out of the gun without the cold, damp, dirty air that is delivered by most compressors. 2. A uniform spray pattern delivering a consistent amount of material all the time. This spray pattern does not require constant adjustment like the conventional and HVLP guns do. 3. It is a closed airtight system so that you may leave material in the spray rig and bucket for extended periods of time. 4. Only one material line too the gun allowing for more mobility. Excellent choice for high production shops.

 

Spray Techniques

 

Spray finishing skills take a lot of raw gun time to be proficient at. You can speed this process up with proper training and coaching. A very simple concept I express to my spray man trainees is; Spray until the surface just gets wet, no more and no less. If you spray too dry, the material won’t flow and will be rough. If you spray too wet, it will and run and fall down vertical surfaces or pool and puddle. Your goal is to get the material to flow and become one even uniform coating with no orange peel, dry spots, runs etc.

 

Always start from the up wind end of the work and spray away from you towards the face of the booth. You don’t want to spray into the airflow of the spray booth as this will leave overspray on previously finished parts and the spray man too. Shoot all edges first and try to shoot your best surfaces last. Cabinet boxes should be shot from top down, working from inside out and horizontal bottoms last.

 

Lapping the material. The general rule of thumb is to overlap your spray pattern by 50 %. This is not set in stone. It can vary depending on the speed you are moving your spray hand. Just remember the basic principal. Spray until the surface just gets wet, no more and no less. Be sure to overlap the leading and trailing edge of a panel to apply a uniform coating to the edge.

 

Six to eight inches away? Again this is a rule of thumb that is not written in stone. Hold the gun the distance from the surface that produces a coating that is just wet.

 

Watch the material coming out the front of the gun. Don’t watch the gun or the surface you are spraying. Keep your eye focused on the material flowing out the front of the gun. This technique gives you a better perspective on how much material is being deposited on the surface.

 

Samples

 

To live or die by your sample? Variations between samples and finished product are to be expected in natural materials that are assembled and finished by hand. This is a concept that your clients need to understand. It should presented in an educational manner so as not to offend or lead the client to believe you will not try your hardest to achieve the look represented by the approved sample. Variations in color and sheen of finish occur do to variations in natural wood colors, variations in porosity of different wood species, changing lighting conditions, etc. You should express to your customer that every effort will be made to achieve the overall effect depicted by the approved sample. This effort is what differentiates between custom finishing and factory produced assembly line finishes.

 

Stain Finishes

 

Surface Prep – Filling nail holes and minor defects with solvent-based filler is the first surface prep step. You want to leave as little putty on the surface as possible as the filler is hard to sand. The entire surface should now be sanded with 180 grit sandpaper to remove residual putty, dirt, pencil marks, fingerprints etc. I recommend no fill paper as opposed to garnet. If your milling department is leaving too many saw and milling marks in the material, it should be improved. The milling department should be providing the finish shop with stain ready material.

 

Stain Types and Their Uses. The two types of stain we will discuss today are oil based and water based stains. The basic difference between the two will be in appearance and safety. Water based stains and their related finishes are generally milkier or waxy looking compared to oil based stains. However the water-based stains are safer to handle and are more environmentally friendly, as they have no harsh solvents or oil in them. Oil based stains and their related solvent borne finishing systems will produce very transparent and clear stain finishes. Stain rags should be soaked in water in a closed container and disposed of according local regulations.

 

Out Of the Can or Custom Mixed? Use out of the can stains provided by your supplier when ever possible to save time and maintain uniformity between samples and finished product. Mixing stains between stock out of the can stains to achieve a specific color is the next step in providing a custom color for your client. If you desire to take the next step in providing your clients with truly custom colors, you can dive into the world of custom mixing concentrated pigments into the appropriate stain bases. This process requires an understanding of color theory and how the basic ingredients relate to each other.

 

To stain or to glaze? That is the question. Stain open grained woods like oak, birch and ash to achieve a more natural and transparent look. Glaze closed grained woods such as maple, cherry, pine and fir to prevent blotching and promote color consistency.

 

Water based stains on raw wood tend to be blotchy and raise the grain. It is recommended to either glaze the stain over the sealed surface or spray shade the stain on the raw surface with the spray gun and leave it alone; that is no wiping.

 

Glaze is stain medium that is hand applied, “glazed”, (with brushes or rags), over and in between finish coats. This is what differentiates the glazed, finish from a stain that is applied to the raw wood. This finish is typically applied to softwoods or closed grained woods such as, pine, fir, maple and cherry wood. “Glazing the wood”, provides maximum color control and prevents blotching. In addition glazing naturally highlights all details and distressing and creates that warmly aged patina exhibited by fine old furnishings and cabinetry.

 

Sealing – A sanding sealer is usually the same material as the finish with the addition of a sanding paste added to it. It is a slippery soap like substance that allows for easy sanding of the surface in preparation for the topcoat. Some finish coatings like polyurethane will seal themselves with a thin first application. (Demonstrations)

 

Prep for Top coating– Sand with 220 or 320 grit sandpaper. Rub with red scotch brite.  

 

 

 

Top Coating – We will discuss three types of finish today. Lacquer, conversion varnish and water borne lacquer.

 

Solvent based lacquershave been the standard of the furniture and cabinet finishing industry for years due to their excellent clarity, ease of use and versatility. In California they are slowly being phased out as the SCAQMD has deemed them to have too many polluting compounds in them, (volatile organic compound or voc). In addition as they have decreased the voc’s in these products they have become harder to use and not as durable.

 

Conversion varnishis the finish that I am most excited about recently. It is essentially a catalyzed varnish that offers the ease of use of lacquer while eliminating the number of coats applied to achieve the same film depth and appearance of lacquer. My standard eight-coat lacquer finishing process has been reduced to four coats of conversion varnish. In addition as this is a catalyzed finish it offers superior wear and tear and durability. This product sprays and dries almost like a lacquer but has the build and full-finished look of varnish. It is voc compliant.

 

Water borne lacquer is the finish that we will be demonstrating today as it is the material that is used on a daily basis here at the Closet Factory. The paint industry has been continuously improving this product since the late eighties when the SQACMD pronounced that they would be slowly phasing out heavily voc laden finishes i.e. solvent borne lacquer. Many furniture manufactures and other heavy users of solvent based finishes relocated to Mexico and other U.S. states with less regulation during that time. Today some shops are returning and new shops are opening due to improvements made to these waterborne finishing systems. This is a superior product compared to what was available ten years ago and will continue to improve. The advantages of this product are, its very low voc content allowing shops in California to use this material virtually on an unlimited basis. The use of synthetic acrylic resins in this material yield a very durable non-yellowing finish product. In addition due to the minimal evaporative solvents in this material you need less applied coats to achieve an acceptable finish as compared to solvent borne lacquer. The primary disadvantage to this material is the drying time that is still slow compared to faster solvent borne finishing systems. The higher the humidity the slower the drying time. This slow drying time can be improved with warmer, dryer air ventilated through the shop. Heat lamps can be used for work that needs to be finished very quickly. Another disadvantage is the slightly milky or waxy appearance of the final finish detracting from finish clarity.

 

Paint Finishes

 

Essentially all of the information provided pertaining to stain finishes as far as surface prep, priming, (which is basically the same step as sealing), prep for top coating and top coating are the same for painting. The materials are essentially the same with the addition of titanium dioxide and pigments to provide the color and hue.

 

 

Touchup

 

For holes, scratches and minor defects, I use colored wax sticks and putties that are available from furniture finishing suppliers. For larger repairs it may be less expensive to simply replace the part instead of spending hours on repair and touchup that may never be acceptable to the client anyway.

 

Minor color touchups can be performed with colored dye stain markers available from furniture finishing suppliers and art stores. My most often-used touchup marker is a black Sharpie pen. Dab the pen onto the area to be touched up and quickly rub it out with your finger to blend into the surrounding surface before it dries. For touchups that require more than what a marking pen can provide; I use straight concentrated Universal Tint Colorants, (UTC). The dry powder touchup kits that are available are great but they are expensive. I use the UTC stain pigments because I stock them any way for the custom mixing I do. In addition they are ready to apply straight out of the can, thinned with a little paint thinner or naphtha if necessary. 

 

Feather outthe area to be touched up with 220 or 320 grit sandpaper. If you leave a sharp, distinct line between the raw wood area and the adjacent stain it will be very difficult to blend that new touchup into the existing stain color. To feather the area you must sand the affected area until the underlying raw wood color graduates slowly from the raw wood color into the fully stained surrounding area.

 

Start applying colorthat is lighter than the surrounding color. Pad or stipple the color onto the effected area. Simply brushing color evenly onto the surface is usually ineffective as it appears like a paint smear. Padding and stippling the color on diffuses the color onto the surface. You want a slightly busy application that will blend the touchup into the surrounding area. Allow to dry for a little while then apply a couple of coats of finish. Apply your final color to blend in with the surrounding area again padding and stippling as necessary for texture. Apply finish. Rub out and polish to remove overspray and blend finish.

 

Standard rub out materialsare 0000 steel wool with a good quality furniture cream or polish. A lot of polish and light rubbing is usually enough. If the 0000 steel wool produces a sheen that is to shinny try 00 wool; be careful not to rub too hard or you may remove your touchup. Buff with a clean rag. 

 

Reference Materials / Trade Magazines

 

Professional Refinishing is a new free trade magazine. I have been impressed with the quality of the articles. (81 8) 715-9776 / www.prorefinishing.com

 

PWC / Painting and Wallcovering Contractor is another free trade magazine that has good articles once in awhile. (314) 961-6644 / www.paintstore.com

 

Finishes and Finishing Techniques and More Finishes and Finishing Techniques are two books that are compilations of articles published in Fine Woodworking, another trade magazine with some great articles in it. ©

 

Thomas Cravens Shop address

15746 Arminta Street · Van Nuys, CA 91406

Cell # (805) 341-7713 · Fax # (81 8) 908-8061

Email: ThomasCraven@msn.com

Web Site: TCWoodFinishers.com

© November 2008 by Thomas Craven ©

 

 

this materil is copy write protected, please feel free to print  and use the data contained here in If you intened to re publish this material please contact Mr. Craven and gain his specific permission.

January 12, 2009 Posted by | Spray techniques, Tips and Tricks, Uncategorized, Wood finishing | 1 Comment

a few things to be aware of when using waterbase finishes

I have just come  from a mans house who recently refinished his kitchen cabinets, he wasn’t a professional finisher when he started the project but was interested in the game and had the spirit to jump in and figure things out. He came into the store and asked for a water based material as he was going to be doing this work in his house and garage while the family continued their daily lives. choosing a water based material was a correct choice.

The gentleman was friendly, enthusiast and good spirited but not at all familiar with the trade so I told him that if he were to have any trouble to give me a call. Sure enough Saturday morning I got the call. He was having troubles for sure but they were easily resolved with the right spray gun that I lent to him from my collection.

Having the right size gun is essential with water based materials a 1.7 mm tip or a 2.0 is what I prefer.

Now then, all went smooth from there on out until his wife got a little glue on the surface of the finish and tried to take it off with 409 and a rag. To her great shock she took off the glue and all the finish right down to the bare wood. That was the living end, after all that work! the wife was in tears, the husband was in despare after all that work and both decided that the sales guy was going to have to be shot for this grieviouse mis-repesentation of the product!

The next day I got a call from the husband who was now under the impression that the whole system was a failure and that it all  had to be redone — Why was the coating so soft ?

On close inspection he did apply the material correctly and didn’t over load the materials on the surface, he used a water based grain filler and so was OK there (  had he used a solvent based grain filler and had not let that fully fully dry, like 48 hours or more that  would have caused problems). So what was going on here?

The answer?  nothing was wrong! the materials just needed a longer cure time. Mrs Enthusiastic scrubbed the glue a mere 48 hours after it had been applied.

409 shouldn’t be used on your new cabinets in the first place even when they are fully cured.

The point here is that you have to let the water based lacquers fully cure.  and full cure comes after 30 days! not that they are not hard enough to install in a few days but if you think that you are going to have immediate abuse then you should hold the parts a few days longer before installing them.

After 4 days of curing the finish was twice as hard. it still loosen up a little and lost some finish with vigorous scrubbing and 409 but it was twice as hard.

On a close study of the KCMA ( Kitchen Cabinet Manufactures Association) tests that the materials passed.  they make the point in  the tiny fine print that the doors tested had been let allowed to cure for 30 days befor they were subjected to the chemical testing.

When you think about it, the water-based materials have to be allowed to air dry. There are no other solvents other than water. The other thing you have to think with is the fact that the materials are going to dry from the top down, I.e they are going to dry on the surface with the deeper and deeper layers drying last.

I have found that once you have let the stuff fully cure it it actually far tougher and far more chemically resistant than their solvent base counterparts.  Ya, just have to let them dry !  

I have promised the homeowner that I would return in 30 days and would test again the hardness of the materials at which point We’ll have full dry and one heck of a finish.

There are two lessons here:

  1. You have to figure in to your equation letting the materials fully cure. That doesn’t mean that you can’t install them until then but if your do install the cabinets you need to know that you have to be gental with the finish for a month or so.
  2. Have the right equipment and read all the printed materials about the materials you are going to be using so that you know what you should expect.

I’ll post the pictures when I get the from the homeowner after the first of the year.

The water based lacquer by the way was Gemini’s titanium white with the white sanding sealer under that

Greg Saunders
ANNEX PAINT
Reseda, California
818-344-3000

November 20, 2008 Posted by | CIC Centurion, water based Conversion Varnish, Finishing failures and the fix, Tips and Tricks, Water based Lacquers, Wood finishing | , , , | Leave a comment

Tips and Tricks

Tips & Tricks

 

1. Switch out your ¼” air hose fitting to high volume 3/8″ fittings and you will increase you Air volume by 30% This will increase your transfer efficiency creating a better finish

 

2. Take your material pails off the floor 10 degrees colder can make your material 30% thicker. In line heaters are available that will heat material to a constant 90 degrees eliminating the need for non compliant solvents and reducers. Your material will dry faster with less solvent entrapment or blushing. 

3. When switching to a water based product you need bigger tips than what you have been using for solvent based materials Not using the proper tip size or a bigger pump will give you a rough finish.

 

4. Using a solvent stain base rather than a Mineral spirits/ Naptha base and you can Top coat in an hour or less rather than having to wait over night.

 

5. When using a NGR Dye stain and Concentrates add 5% of your top coat material to your Acetone dye solution and it will act as a binder for the color reducing the risk of your top coat lifting due to poor adhesion

2. Take your material pails off the floor 10 degrees colder can make your material 30% thicker. In line heaters are available that will heat material to a constant 90 degrees eliminating the need for non compliant solvents and reducers. Your material will dry faster with less solvent entrapment or blushing.

 

3. When switching to a water based product you need bigger tips than what you have been using for solvent based materials Not using the proper tip size or a bigger pump will give you a rough finish.

 

4. Using a solvent stain base rather than a Mineral spirits/ Naptha base and you can Top coat in an hour or less rather than having to wait over night.

 

5. When using a NGR Dye stain and Concentrates add 5% of your top coat material to your Acetone dye solution and it will act as a binder for the color reducing the risk of your top coat lifting due to poor adhesion

 

October 9, 2008 Posted by | Tips and Tricks | | Leave a comment