Replies

1. 
   Ron_Brese | Oct 06, 2001 02:03am | #1

   *
   b From the Workshop of Ron Brese

   Ian I would imagine that a nitrocellulose lacquer would be the easiest thing that you could run thru your gun for the first shot at spraying. Use sample boards to get you thru the learning curve. Start with the material flow adjustment knob barely open and then open it up until you get a decent flow of material with good atomization. You may actually want to run water thru it initially just to get the hang of how the adjustment controls function.

   A turbine driven HVLP will spray medium to light bodied finishes quite well. Make sure you start your spray strokes nearest to you and work away from yourself so that the airflow out of the gun doesn't move the already sprayed finish around.

   I used a turbine for a good while before converting to a conversion hvlp setup. I wanted to start spraying the new Target Coatings Hybrid top coats and the turbine just would not lay down the waterborne high solids finish with satisfactory results.

   Good luck,

   Ron

1. 
   Danford_C._Jennings | Oct 06, 2001 02:04am | #2

   *Ian,Congratulations on the new toy. Liners are a pain, IMO but, then some must like 'em since they make 'em. As for the first time, by all means try the Deft. You gotta' start somewhere.You will find that different products will have different characteristics, always do some tests on scraps of cardboard to get the spray pattern and distance down pat. Just follow what the finish manufacturer recommends. Good Luck. Let us know when you "graduate" to lacquer.b ;)Dano

1. 
   ian_cummins | Oct 06, 2001 08:05pm | #3

   *Ron and Dano, thanks to you both. I just shot some Deft on scraps of cherry plywood and got good results. I couldn't wait to try it even though it's raining here off and on. Also need to get a respirator before any serious spraying.

1. 
   Ron_Brese | Oct 06, 2001 10:41pm | #4

   *b From the Workshop of Ron BreseIan be careful. Unlike some hazardous materials that do harm from extended exposure, the fumes from lacquer and lacquer thinner have accumulative effect. A wif here and a wif there and one day you don't seem to be able to remember what you were doing yesterday. At least that's what I'm blaming for my lack of short term memory. Good luck with the spraying and protect yourself.Ron

1. 
   scott_murray | Oct 07, 2001 05:08am | #5

   *Ron,I've been waiting for an opportunity to bring this up. How many people are using fresh air respirators? I broke down and bought one last year. I just figured that, one, if I plan to be at this wood thing for another 20+ years, maintaining brain cells, etc, should be a priority. Secondly, spreading out the cost of a respriator (roughly 350 bucks american) over that time period versus who knows how many filters I'd burn thru. Lastly, just an uninformed opinion, but I've been told that there are no filters which work effectively for the bad stuff given off by polyurethanes. (Anyone have an educated opinion an that?)We spend a lot of money on tools. I would urge everyone concerned about long lasting health effects of finishes to consider this option. FWIW, here is a link (this is not an ad on my part) for a low cost respirator and more info. (Charles, you'll love the name of this company, "Man of Rubber") http://www.riverequipment.com/ In the middle of the links is the page for fresh air respirators, which at the bottom of that page is the hobby air set-up.the rev

2. 
   Howard_Acheson | Oct 09, 2001 09:40pm | #6

   *>>(Anyone have an educated opinion an that?)Get the Material Safety Data Sheet from the manufacturer of the poly you are using. It will tell you the precautions that should be observed and the saftety equipment used. Every cartidge I have says it can not be used for polyurethane fumes and mist.

3. 
   Jack_Woody | Oct 13, 2001 01:47am | #7

   *When I first started spraying polyurethane it was after reading an article in FWW about filters for "organic vapors". My impression was I needed a cartridge to filter "organic vapors". Polyurethane doesn't sound very organic to me now that I think about it but I don't recall reading on the cartridge or the packaging anything about it not working for polyurethane. Guess I better do some more research.Maybe we can get an article about the latest on spraying, resperators, filters, etc. instead of another router review in FWW.

4. 
   Ron_Brese | Oct 13, 2001 02:49am | #8

   *b From the Workshop of Ron BreseRev I have the same concerns about exposure to solvent vapors as you. This is why I've just gone thru a learning curve on spraying waterborne finishes. Jeff Jewitt fixed me up with an Asturo HVLP conversion gun that will lay down the new Target Hybrid PSL very nicely. I am using a seal coat of garnet shellac in order to have that nice amber undertone, but that still puts me only applying one of 4 or 5 coats of finished with a flammable solvent. The Curly Maple tables I've just finished with this system actually exceed what I think I could have done with all solvent borne materials, and the waterborne lacquer will actually be a harder finish when cured. The other thing about this hybrid lacquer that I really like is that the solids content is about 30%. I could have been at the same surface film thickness after two coats that it would normally take 4 or 5 coats of solvent lacquer to achieve. Don't get me wrong the PSL does have it's quirks, that's why the learning curve is necessary.Ron

5. 
   ian_cummins | Oct 13, 2001 04:03pm | #9

   *Ron, I've called around looking for nitrocellulose lacquer. Of three companies that carry it locally, Duron, Porter and SW, all say they have to special order it and that it comes in 5 gal. only. I'm concerned about shelf life (apparently they are too)and wondering if there are better sources than these typical paint stores. Would appreciate any help.

6. 
   Ron_Brese | Oct 13, 2001 07:44pm | #10

   *b From the Workshop of Ron BreseIan you could just go to the home center and get some Deft spray lacquer, but it is really a little soft even cured for quite a while. Try the Homestead Finishing web site. Jeff carries a wide range of materials and I'm sure he stocks in one gallon containers. Merit Industries has a web site and they carry a wide range of finishing materials also. I would however stay away from the M.L. Campbell high build NC Lacquer, as I had real problems with it this summer and got no help from the distributer or the manufacturer.Ron

7. 
   ian_cummins | Oct 13, 2001 11:42pm | #11

   *Ron, I've been spraying Deft with pretty good results but was hoping that the nitrocellulose would be a bit thinner or at least thinnable. The can says not to thin Deft. I'll check out Homestead, thanks.

8. 
   phil_eves | Oct 20, 2001 02:11am | #12

   *First time spraying? Make sure the lid's up, and clean up before the wife sees!

9. 
   Joseph_Fusco | Oct 20, 2001 02:18pm | #13

   *Ian,

   One thing to remember when spraying solvent based lacquers is that they will tend to "blush" or cloud when using a turbine. The longer you run the machine the hotter the air will become causing the problem. This will not happen with waterborne stuff. In fact the warmer air improves the flow of waterborne lacquers.I use a product from ML Cambell main UltraStar which is an excellent waterborne lacquer. Good luck.

   View Image"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle

10. 
    ian_cummins | Oct 20, 2001 02:57pm | #14

    *Joe, Thankyou for the source. I've been wondering about waterbourne products. I've read that they have a cool appearance and have seen pre-finish products designed to give the warmer look of oil. I see that Ron uses a garnet shellac first for this purpose. Do you find that true with the UltraStar?The main defect I'm experiencing with Deft is orange peel. I can minimize it with adjustments but am still not getting a truly smooth surface and am having to rub out. Have not achieved a final top coat that I'm happy with yet. Any suggestions?

11. 
    Joseph_Fusco | Oct 20, 2001 04:36pm | #15

    *Ian,

    I used to use shellac under may waterborne too. I think I even post that here once or twice. I find that the UltraStar has a bit of a "tint" as compared to earlier coatings. Basically I find it acceptable and not as pale as some others.As far as the orange peel goes, you may not have thinned the material enough. If so the gun can't atomize the fluid well enough. Try adding twice as much thinner then you did and see how that goes. If it's to thin work backwards in 1/4 increments till you get the right mix. One other thing about HVLP sprayer is that you need to stay a bit closer to the work when spraying. I found that between 3 and 5 inches works well. Finally you also need to move the gun a bit slower then with a conventional spray gun.

    View Image"The first step towards vice is to shroud innocent actions in mystery, and whoever likes to conceal something sooner or later has reason to conceal it." Aristotle

12. 
    ian_cummins | Oct 20, 2001 05:30pm | #16

    *Joe, My problem may have been in the thinning. The Deft can says clearly, Do Not Thin, so I didn't. Towards the end of the session, I did add some lacquer thinner out of frustration but maybe not enough to make a difference. Will give it another try. Thanks again for the guidance.

13. 
    Jim_Hassberger | Oct 23, 2001 10:09pm | #17

    *Ian:I've sprayed Deft with very good results, although I prefer SW CAB-acrylics. Go ahead and thin as necessary to get rid of the orange peel.

14. 
    ian_cummins | Oct 23, 2001 11:15pm | #18

    *Jim, I did end up thinning the Deft and got rid of the orange peel. I wonder why they are so emphatic (on the can) about not thinning it. I guess they're referring to brushing and not spraying but it sure caused me some headaches. This time, I really shouldn't have read the directions! Thanks for your reply.

15. 
    Robert_Weiner | Oct 25, 2001 10:00pm | #19

    *In a former life I used to work in the hazardous materials/Haz waste industry. I hope I can answer some of your questions, please feel free to post more or e-mail directly to [email protected] (you guys have helped me with enough info I hope I can return some)First of all... Please please do not spray solvent based finishes -- especially lacquers -- without excellent ventillation. You can very quickly generate a flammable environment and generate a fire or explosion.1) Polyurethanes rely on isocyanates as a curing agent. Isocyanates can not be filtered with a standard organic filter since they saturate it almost immediately.2) The filters you buy for a respirator have a limited useful life. Standard practice is to replace when you smell breakthrough. This is fine except that many finishes esp. shellacs (alcohols) tend to numb your sense of smell as they start to break through. Therefore you can not tell that your cartridges are overdue.3) The above reccomendation about reading the MSDS's that come with the products is an EXCELLENT one. Some things just blow right past respirator cartridges.4) As a generalization, standard respirator cartridges do better with high molecular vapors such as toluene and mineral spirits, and less well with low molucalar weight solvents like methanol and MEK.5) In terms or priorities, I suggest you work in the following order:- Use finishes with fewer toxics. Water based is a good start.- Ventillate as well as possible.- Fresh air respirator is better than a filter respirator, filter is better than nothing.Best of health to you all. Remember, if you want to rot your livers, drinking is a lot more fun than finishing.Peace.-Rob

16. 
    Jack_Woody | Oct 27, 2001 02:51pm | #20

    *OK, So if the standard organic cartridge does not filter isocyanates, and the way to determine a depleted filter is when one can smell through it, than how is it I don't smell anything or get the least bit dizzy, naseaus, using a cartridge that I've had for years?

17. 
    Robert_Weiner | Oct 27, 2001 08:05pm | #21

    *Jack-Maybe you don't use your respirator very often and take excellent care of it when not in use. Maybe you have good ventillation. Maybe your nose gave up the ghost a while ago. I don't know.One thing I do know, if your cartridges have not been replaced in years, then they are probably not much more effective than a cotton rag. They are doing very little for you.I don't mean to pick a fight, but I do take this stuff seriously. If you want to do everything possible to protect your health, then you should take as much time learning and understanding your respirator as you do your router or bandsaw. You have ten fingers, but only two lungs and one liver.I know of people that smoked a pack a day until they were 90, but I would not recommend it a health tip. I can't say for sure that taking fewer precautions will make you sick in ten years, but the odds are more in your favor the more you careful you are.If you want to extend the life of your cartridges, here are a few things you can do:1) When not in use, remove the cartridges from the respirator and store in air-tight bags. Ziplocks work fine.2) The moisture in your exhaled breath can fill the pores of the activated carbon reducing efficiency. Therefore, make sure all of the valves in your respirator are working properly. Air should come in through the cartridge, but out through the exhalation valve. One way to check this is to hold your hand over the exhaltion valve and try to breath out. The respirator should lift from your face and not vent through the cartridges.3) If you use your respirator several hours per week, then replace your cartridges every 1-3 months. If you use your respirator less frequently, then replace them every 3-12 months. These numbers are approximations, but you can actually get a chart from your cartridge manufacturer that gives breakthrough times in minutes for each of several different types of compounds. If you use this in conjunction with the chemical data on the MSDS you get for your finish, then you can figure out how often to replace your cartridges.Be safe.Peace.-Rob

18. 
    Jack_Woody | Oct 29, 2001 12:13am | #22

    *i Maybe you don't use your respirator very often and take excellent care of it when not in use. Maybe you have good ventilation. Maybe your nose gave up the ghost a while ago.]Rob, Thanks for the advice!! Maybe my nose is not as good as I thought it was. I follow your suggestions 1 and 2, and do not really use it all that often. I will get with a local company that specializes in respirators,cartridges, etc., and make sure I get the right ones.]Thanks again,]Jack.

19. 
    Robert_Weiner | Oct 29, 2001 10:08pm | #23

    *Jack-Glad the info was helpful.Peace.-Rob

20. 
    davamoore_ | Nov 17, 2001 03:58pm | #24

    *Guys --I found your safety information to be very helpful. Unfortunately, it's buried in a discussion about sprayers, and since I don't own a sprayer I skipped over the topic for the past 5-6 weeks, until I happened to be screwing around this morning, drinking an extra cup of coffee, delaying a final pass at the leaves in my yard. (Plus, it's deer hunting season here, and I'd rather duck the bullets in broad daylight than in the fuzzy, foggy light of dawn.)Just a suggestion (because I think this safety information is important): maybe one of you could cut-and-paste the respirator part of the discussion into a new topic with a headline that gives a clearer indication of the subject. I would try it myself, but I'm not the author -- and being a freelance writer myself, I'm oversensitive to improper use of people's words! (Even on a public forum such as this.)In any case, thanks for the info.David

21. 
    Jeff_Jewitt | Nov 18, 2001 06:39am | #25

    *I'd like to mention several things here about polyurethanes and respirators and such. First of all, there is a distinction between "unreacted urethane" and reacted or cured urethane. There are many different kinds of resins used in wood finishes, but the two main ones are called two-component urethanes (unreacted) and oil modified urethane/alkyds (fully reacted)Urethane is formed by the reaction between an isocynate and a polyol. The isocyanate portion is what is hazardous. When fully reacted urethane is not hazardous. As the above poster indicated, isocyanates will quickly saturate an activated carbon cartridge, but more importantly, isocyanates are odorless, and once the cartridge is not filtering, the user is unaware of isocynates coming through. That is why there are no negative pressure respirators (cartridge style) that are tared for isocyanates. However positive pressure resiprators are rated for isocyanate use. For normal everyday polyurethane, the stuff that we use from Home Depot and such, a regular cartridge style respirator is fine as the only harmful ingredient is mineral spirits. Since this may or may not make sense, the easiest way to judge is if the polyurethane is a single component finish in a can, you can use a regular respirator. If it's a two part finish, use a positive pressure respirator like an air-supplied respirator. The one I use runs off my compressor. Unfortunately this distinction is not noted nor used by respirator supply componies. If you tell them polyurethane, they'll assume the worst case scenario and say a cartridge style is not recommended. In about several issues, I'll have an article in FWW on respirators and a guide for selection. Jeff

22. 
    johnny_g | Nov 23, 2001 06:48am | #26

    *Hi I have a Q4anyway I don't use liners and have had no trouble cleaning the unit.Deft is actually the first (laquer) brand I used.Be carefull Use a good respirator with a face shield! At first I just used a respirator. It get to your eyes.I'm not like you, I charged ahead didn't read the manual right and still got good results. One thingstart with lighter coatsjohn g.