Replies

1. 
   TomT226 | Nov 05, 2003 03:25pm | #1

   I use both nitro lacquer and water base lacquer. I like nitro lacquer for pieces that don't get hard use.

   The water base stuff I use is Target PSL. It has 100% burn-in between coats, and is much, much harder than nitro.

   The water base is easier to clean up after, as you use water to flush pots, hoses, and guns. Smells faintly of cat piss, but that goes away after it's dried.

   Both have roughly the same drying times in low humidity, 70-80 deg. temp range.

   Go to http://www.homesteadfinishing.com and check out the info.

1. 
   PlaneWood | Nov 05, 2003 09:31pm | #3

   Tom -

   Here around Houston, we NEVER have low humidity days!  Would that be a consideration??

   Also, I just use an air compressor and an el-chepo hand held gun with a quart tank.  Would that be a consideration in which to use?

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood

1. 
   Paul_Snyder | Nov 06, 2003 02:48am | #6

   Environmental issues are a consideration to choose a waterborne finish. With tightening regulations on solvent emissions, waterborne finsihes may be the only option in the future.

   But there are some other good reasons to choose waterborne (WB) finishes that come to mind.

   - They do not present an explosion or fire hazard.

   - You don't need a storeroom of chemicals like lacquer thinner, lacquer retarder, acetone, MEK, MAK, butyl cellusolve, toluene, zylene, naphtha, mineral spirits, etc.

   - They don't blush in hot, humid weather.

   - They are not sensitive to moisture in the airline (though water drops that come through the air line will leave a spot in the finish).

   - The fumes are less hazardous to personnel (you still need a respirator if spraying).

   - They don't have the strong odors associated with solvent finishes which makes them a good candidate for on-site work.

   Some brands of WB are better than others. The common complaints, like those listed in the other responses, are not true of all waterborne finishes. The Premium Spray Lacquer (PSL) from Target Coatings is my favorite (I've tried a number of brands; some in large quantity). In addition to the properties that Tom cited, this finish has outstanding clarity (ask Jeff Jewitt as Forest Girls suggests), there is no bluish "haze," it rubs out very well, its chemical and water resistance ratings are the same as CAB lacquers and its hardness rating is on level with conversion varnish. It's not the most durable WB finish Target has, but it's the most versatile (in my opinion). Target has an oil-modified varnish that can be brushed or sprayed and it has an amber color like some oil-base varnishes.

   Learning to use WB is like learning to use any other finish. If you click on my name in the "From" line, you'll see a poor picture of a weeks finishing I did (with a helper) using PSL.

   Paul S

1. 
   Tao | Nov 08, 2003 07:35pm | #11

   Paul, most of your observations are correct, but there are a couple of them that  could be dangerous misconceptions.

   I was looking through some of the MSDS sheets on waterborne finishes that I have on file, and here's what I found:

   Health hazards:  Most of the waterborne lacquers I looked at had the same HMIS health rating as lacquer, that is, 2.  They warn of lung damage as well as permanent brain and nervous system damage.  They should never be used without the same ventilation as solvent lacquers.

   Flammability: HMIS rating 1 as compared to 3 for lacquer.  Definitely less risky, but still flammable.  They all say do not expose to high heat, sparks, or flame.  The dry overspray consists of urethane and acrylic resins, which usually burn easily in powdered form.  In thirty years of industrial  and custom finishing, I have never seen or heard of a fire resulting from actual spraying.  However, I have personally witnessed five fires involving the ignition of dry overspray.

   Chemicals found in waterborne finishes include many that are found in sovent systems: n,propoxypropanol, proylene glycol monomethyl ether, dipropylene glycol monomethyl ether, 1,2,4 Trimethyl benzene, aromatic naphtha, 2-propoxyethanol, butoxyetoxyethanol, propylene glycol n-butyl ether, etc.  I believe all the glycol ethers ae flammable. and none of them are good to breathe or ingest.  I believe the same can be said for aromatic naphtha and the benzene compounds.

   Bottom line is, waterborne finishes should probably be handled and applied just like solvent lacquers.  I think they are more dangerous because the term waterborne or water based implies safety to most people, and they won't be nearly as careful with them.

   It would be a great service if FWW and other publications would do some articles examining these issues, if they are not too afraid of their advertisers.

   Michael R

1. 
   Paul_Snyder | Nov 08, 2003 09:15pm | #12

   Michael - I agree that the material safety data sheet (MSDS) is a good source for safety and hazard information. It's a good idea to consult the sheets when using finishing products sicne they all contain chemicals of one type or another. When the manufacturer of a product produces an MSDS, they make sure to err on the side of safety. They advise the strongest safety precations to ensure they are not liable for any mis-use. If you follow the safety guidelines in the MSDS you will remain unharmed.

   The MSDS for the waterborne finish I like (Premium Spray Lacquer [PSL]) from Target Coatings has the following information in their MSDS (PSL MSDS);

   Section VI - Respiratory Protection - none required in well ventilated areas. An approved organic vapor full face respirator is advised for poor ventilation or spray application.

   Ventilation

   Local Exhaust - none required

   Section IX - Fire and Explosion Hazard Data

   Flammable limits

   Upper - not applicable

   Lower - not applicable

   Section X - Hazard Rating Information

   Fire - 0

   The best advice that comes to mind is to always get the MSDS for the products you (anyone) plans to use. Follow the guidleines in the MSDS; the manufacturer advises a level of safety that will keep you from any harm. The number #1 concern I've seen with all the different brands of waterborne I've used is the requirement to use a respirator when spraying. Airborne particulates and solvents present the greatest hazard. As part of any good "housekeeping" policy in a shop, don't allow dust to accumulate.

   Paul

2. 
   Tao | Nov 08, 2003 10:34pm | #13

   Paul, it seems that PSL is not only one of the better waterbornes available, but one of the safer ones, too.  The MSDS sheets I have are for Valspar and M L Campbell products, and they all show a flammability rating of 1.

   I do notice that the toxicity level is still the same as for solvent lacquers, and that they recommend  a full face respirator for spraying.

   They also recommend to keep away from sources of ignition, even though the flammability level is zero (?).

   I confess I don't understand the part about local exhaust - none required.  I wouldn't find that necessary if I were brushing it, but for spraying it I would either want to be in an open area with a cross draft, or have a good exhaust system.

   What I am primarily trying to warn against is people thinking they can spray this stuff in their basement with little or no ventilation.  You're a pro, and a good one by the looks of it, so I know you take appropriate precautions, but some folks seem to think that because it says "water" that it's as safe as water, and that's far from true.

   What you said about housekeeping is very important, too.  Acrylic dust burns real nasty.  The fires I saw were in industrial situations.  One was from welding sparks hitting a surface coated with overspray, two were from overheated motors covered with overspray, and two were from spontaneous combustion where stain dust was mixed with lacquer dust.

   Michael R.

3. 
   Paul_Snyder | Nov 09, 2003 02:55am | #14

   Michael - there's a line from an old TV show that sticks in my mind (even after these many years);

   "Let's be safe out there."

   Sage advice. Thanks for the reminder. ;)

   Paul

2. 
   TomT226 | Nov 07, 2003 02:33pm | #9

   Well, I'm up here around Elgin, TX, so our humidity levels are about the same.

   I don't think it matters. I spray with both conventional and conversion HVLP and get good results. If the day is real cool and humid, just spary light coats with a minumim of 2 hours between. No more than 3 coats on a day like that. I also like to keep some air moving around the piece with a fan set on low.

1. 
   PlaneWood | Nov 07, 2003 07:16pm | #10

   Tom -

   An old retired gentleman that worked all his life for Ethan Allen as a furniture refinisher here in the Houston area once told me to always keep air moving over a piece when spraying lacquer.  It certainly helps to prevent blushing!

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood

2. 
   forestgirl | Nov 05, 2003 08:04pm | #2

   I consider "ease of clean-up" a major advantage.  However, water-based finishes can be deficient with respect to the "depth" they add to the wood when finished.  Jeff Jewitt's site should be a good resource.  His book, "Great Wood Finishes" has a good pros-and-cons section on water vs. oil.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

3. 
   RANGERP75R | Nov 06, 2003 01:49am | #4

   Mike

      The only time I have ever used water-based is when I don't want the amber-tint from finishes containing oils. It drys almost clear (very slight haze). It is not quite as hard when cured as oil-based poly. About the only time I use any poly period is for peices that will get high steam exposure (kitchens and bath-rooms).

   Luck...

   sarge..jt

4. 
   Shep | Nov 06, 2003 02:29am | #5

   I think that the biggest advantage, besides the easy clean-up, is that most water-base finishes dry very quickly. I use Crystalac, which can be recoated in about 30 minutes. This means I can put 3-4 coats on in just a few hours.

5. 
   Joe_Fusco | Nov 06, 2003 04:39am | #7

   PlaneWood,

   Another reason is how easy they clean up. Some warm water is all that I use. One excellent product that I've used is Fuhr 255. You can brush, wipe it or spray it. After it fully cures it has excellent durability. You can find out more about other Fuhr products here.

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1. 
   PlaneWood | Nov 06, 2003 04:53am | #8

   Ok, looks like there's certainly enough reason to try it!  Non blushing really would be a plus down here for the lacquer!

   Thanks all!

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood