another hvlp thread

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Okay, the last hvlp thread went so well, here's a question I've been meaning to ask.
Everyone (ok, not everyone, but notably Robert, Swingman, BARRY, etc...) has been talking about shooting lacquer (flammable), oil poly (flammable), shellac (flammable), stain (flammable).... What kind of explosion proof set up/equipment are you using? Or are you? (I won't tell if you're not). My thinking has been that I can't spray any of that stuff since I don't have the 'right' spray booth with the 'right' fan/exhaust etc... What I do have is some heavy weight plastic hanging from both runners of one of my garage/shop doors, a third which basically lays across the inside of that door (I have it hanging from a piece of conduit laid across the door tracks) and one more that I can pull across the top as a cover. This creates a nice booth, but I worry about combustibles.
Any advice on what I should/should not worry about? Your experience?
Thanks,
Joe
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With that setup you should be more worried about ventilation than combustion. I paint with a similar setup - hanging plastic from ceiling to floor making up two walls, but that creates a paint are two car bays wide. I use a 24" ventilation fan to suck the stuff out of there, and that's often not enough. Especially when I shoot clear coat on a large area. You're not likely to ever encounter a combustion problem, but I can assure you - you have encountered ventilation problems. This stuff is bad to breath and unless you're using positive pressure ventilation, you're breathing what you're shooting. No matter how good you think your mask is. It isn't.
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Mike, while I agree with your caution about the health danger I disagree with "You're not likely to *ever* encounter a combustion problem".
Many finishes are quite flammable, especially laquer, and adequate ventilation is essential for that danger too. Compressor or turbine motors (even when not within your spraying enclosure) present a spark hazard that should not be disregarded.
Cheers.
Michael
p.s. Here's a tip that I learned decades ago when spray painting cars and it's applicable when spraying finish on any project. After throughly sweeping the floor in your spray area, wet the floor lightly (no puddles) and this helps keep micro particles of dust from being kicked up as you move around the work area.
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The potential is always there with combustibles, but the likelihood isn't always. You have to hit concentration levels. Certainly, one can, but it is far less likely than the exposure issues.
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What Mike said.
And don't be fooled by water based finishes. Some have formaldehyde, ammonia, glycols, and all manner of other nasties in them. In some cases I think they are probably more dangerous than the solvent based stuff.
Every year around here, we seem to have some ignats blow himself up by spraying something flammable in his garage that houses his gas clothes dryer or water heater. Don't spray anywhere around any kind of flame.
I often shoot in areas that aren't conducive to proper ventilation, so I time my spray schedule. I spray, I leave the area. I usually don't go back into the spray area until it is time to test for dryness, so that can vary. The point is, I don't hang around. When the sprayed material can stand some air, I open things up. I don't worry about explosions.
Once again, I agree with Mike. Your mask is a must, but it ain't all it should be. DO NOT - DO NOT - DO NOT save money on your mask. Get the best one for the job, and change those damn cartridges out often. I know finishers that have had the same cartridges in their masks for a year or more. They don't seem to understand that the charcoal filtering goes stale and won't work.
Wear clear eye protection to keep your eyes from getting any finish in them.
After seeing an old painter I have known for a long time a few years back, I noticed he had the shakes. His doctor told him it was because of his constant exposure to mineral spirits, lacquer thinner, paints, etc. from the days when they didn't use any kind of protection. I now wear cheap nitrile gloves most of the time when I spray, and always when I clean.

Everyone should frame that and hang it in their finishing room.
Robert
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Take a look at the 3M 6800.
Can be used to shoot L/P in the boat yard.
(VERY NASTY)
Next step up is a self contained unit with a bottle on your back which pop up from time to time on eBay.
Lew
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snipped-for-privacy@aol.com wrote:

I use a 36" industrial fan from Costco and with taped-on filters to draw air through the shop with WB. Makeup air comes from upstairs in the house.
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wrote:

I was thinking about one of those, especially with the size of the booth. What kind of filters do you tape on to the face of it?
Joe
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joe wrote:

"Furry" woven furnace filters.
The only purpose is to catch finish droplets before they get to the fan blades. I think paper would also work, but would probably clog sooner.
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wrote:

Got to be a bit careful with them also.
Before converting the manufacturing plant to powder coating, used a ransburg liquid system with filters to catch the paint solids and solvents. At the end of the day, they would be taken down and replaced, the used filters put in a steel dumpster to be taken to an incinerator. Sometimes they would spontaneously combust on the forktruck ride to the incinerator. Caused great excitement.
As long as the air is being pulled through them OK, but if you take them down, wad them up, let heat build up......
Frank
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Frank Boettcher wrote:

I only use them for water base.
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Since we are another theme, let's talk about the various water based products.
I was told that you couldn't "rub out" a water based products, because it would leave scratches.
Is that true ???
What products do you shoot ?
B A R R Y wrote:

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Absolutely not. Of course you can rub out water borne, it is just a question of technique. These guys say it better than could. Have a look:
http://tinyurl.com/2jahcr
http://tinyurl.com/3ccc88
And finally for an idea of some methods:
http://tinyurl.com/3yu4e3
I don't have it any more, but I used to have a picture of a can of Oxford coatings wb lacquer sitting on a table that had been buffed to such a high polish it literally looked like it was sitting on a mirror.
I'd bet too, that very few people outside of the professional community know that the vaunted Piano Lac is actually water borne.
If I were to shoot water borne, I would go with MLC Cambell Ultrastar. Never used it, but is ease of application, compatibility with equipment, and its durability is well known and established in the finishing community.
Besides, if I did that I could PING Barry when I goof up!
Robert
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On Wed, 5 Mar 2008 07:50:49 -0800 (PST), " snipped-for-privacy@aol.com"

I intend for that to be my plan.
Frank
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I keep forgetting about the WoodWeb for some reason. That's a nice little series of posts on the subject.
My problem is just getting the product at times. My area is heavy tourist and very little industrial, so finding the better finishing materials can be trying.
A lot of finishing folks can't ship certain products from what I have seen.
The water based stuff sort of appeals to me but I'm very rookie in the spraying business.
I'm determined to learn the process.
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Pat Barber wrote:

Some of the waterborne products don't "burn in" between coats, so rubbing out can leave lines where the different layers are.
Quite a few people like Target's "Oxford Ultima Spray Lacquer". This stuff is waterborne but each coat chemically melts into previous coats so that it can be levelled and rubbed out properly.
I haven't sprayed it, but have brushed it. I've only used it once so far, but plan on using it again.
Chris
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Pat Barber wrote:

I use one water based product on a regular basis, ML Campbell Ultrastar. I prefer the dull sheen (same as nitrocellulose) for most furniture, but have tested satin mixed with 30% latex paint for an excellent pigmented lacquer look.
With ML Campbell Ultrastar, I certainly can rub it out. There are other WB lacquers (Fuhr, Target, etc...) that claim the same, but I have no first hand knowledge of them. Certain products can leave "witness lines", which are visible lines as you break layers. I haven't seen them with Ultrastar, and I shouldn't, as ML Campbell claims "full burn-in" between coats.
I use Ultrastar because it works well for me, dries very slightly amber - no "blue cast", I can get it locally (Pratt & Lambert paint sellers can get it), and I get it for $28/gal. Some of the good "boutique-sold" WB lacquers sell for $25 or more per QUART! 8^(
The problem with statements about what "Water Base" can and cannot do, are the wide variations between products. In general, home center water base polyurethanes have never lived up to my expectations. I personally think they flat-out suck, are way overpriced, and leave a "dead" look.
Where I want a solvent lacquer look, say on red or white oak, I rub the wood down with "Robert's Sealer", an equal mix of real Turpentine, Seal Coat shellac, and boiled linseed oil. After an hour or so, I scuff it with 320 and rub it again. The next day, I apply one coat of Ultrastar sanding sealer and two coats of clear, in my desired sheen. The sanding sealer and first coat of Ultrastar are scuffed with 400 grit after ~45-60 minutes, depending on the temperature. The sanding sealer dries quite shiny, making it easy to see where you've scuffed.
If the room temperature is below ~72F, I warm (DO NOT HEAT IT, only _warm_ it!) the product in a hot water bath to improve flow-out. I spray unthinned Ultrastar directly from the can, with no additives, but run the well-stirred product through medium mesh stainers (from the same paint store) as I put it in the spray cup. On the Fuji 4 stage, I use a #3 setup with a suction feed cup or pressure pot, and a #4 with gravity feed cups. (2) 2x500 watt work lights (Home Depot) set up to provide low-angle, raking light, further warm the surface and make it easy to see what I've sprayed. The lights shine across the surfaces, highlighting missed areas. I haven't seen any humidity related issues with this product.
I spray the edges, then do one coat the long way, and another the short way. Each coat is made up of overlapping strokes that move into the overspray. I apply full and wet (this is what takes practice), but not overly thick coats. Do not "tack coat" with Ultrastar. If you screw up big time, LET THE FINISH DRY, then fix it. Both of these procedures are different than solvent lacquer. Many times, what looks like a screw-up will dry just fine, but attempting to mess with the wet finish will make it worse. Building too thick of a shell will look ugly, but most any film finish product will look like crap in a too-thick shell.
A properly sprayed surface will dry dust-free in 10-15 minutes, max. If it's not dry, it's too cold, or you sprayed too heavily. Under applied product will come out gritty. Properly applied, 1 or 2 "Robert's" rubbings, a coat of either Seal Coat or Ultrastar sanding sealer, and 2 coats of Ultrastar, will still not overly clog the pores of red oak, leaving a very, very nice look.
If I used an oil-based stain, I verify dryness by rubbing with a clean cloth, and usually substitute a barrier coat of Seal Coat for the Ultrastar sanding sealer. Ultrastar goes over natural maple or birch with just a tinge of ambering, almost water clear.
As usual, use some time, properly prepared scrap, and plenty of finish, as practice to invest in your finishing skill. No matter what the product, I usually spray a few ounces on the wall, my bench bases, practice panels, etc... before I aim the gun at the project.
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Well, that pretty well covers it. I'm like Swingman, I'm saving all the posts on the subject from certain people. I'm behind but I'll catch up someday.
B A R R Y wrote:

Snipped the rest of the finishing manual on water based products.
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"Pat Barber" wrote in message

Yeah ... and I forgot to add B A R R Y to that list of 'must save' finishing info, along with Mike Marlow and Robert (nailshooter).
Mea culpa ...
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Sheeee-it, B A R R Y's in MY list of must saves. Of course Robert is also, but I'd already admitted that a while ago.
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