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Hi all. This is my first time on a forum like this and I am relieved to have found it. I am having a lot of trouble getting a smooth finish on a dining table top. I've been spraying an M.L. Campbell pre-catalyzed lacquer through a relatively new Earlex HV7000 hvlp turbine spray system. I have had to sand off 4 failed attempts at a top coat. I am getting either a rough dry coat or orange peel . No happy medium seems to exist. The smaller test pieces come out smooth yet no luck once I move to the table. I've tried thinning the lacquer by 5% and also using no thinner at all. Should I thin it at a greater ratio? Have also tried with a 1mm needle and a 1.5mm. Also cannot seem to eliminate brighter stripes on the surface even though I am doing a 50% overlap. Feel like I've tried everything. Would love some suggestions.
Thank you.
 

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The problem may be the HVLP gun. I've never been impressed with them. I prefer to use a siphon sprayer and for wood finishes doesn't have to be a high dollar gun. I finish table tops with a cheap harbor freight #97855 siphon sprayer I get with a coupon for about 16 bucks. The problem may also be that the finish is not thinned enough. I haven't used that brand of lacquer however you may need to thin about 40%. The only lacquer I haven't had to thin that much is one that is labeled "Ready Shoot". I don't like to use it but sometimes it is necessary to use retarder thinners to eliminate the lap marks, especially in hot weather. It slows the drying time down so the finish flows together better. The downside is it takes a great deal longer for the finish dry between coats and even longer to cure after you are done.
 

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Hi Red, Steve is right for sure. I've used the Campbell product before in fact that is what i sprayed when i was learning. It is very hard to get a smooth finish on a large piece like that. Even though you are over lapping 50% your previous pass is already setting as you make your next pass therefore leaving you with stripes. You can look for a product called Chemcraft
Vericure precat. This is the only product I've ever used with an hvlp gun that melts together like glass. I sprayed it right out of the can no thinner no retarder. Made my table tops look awesome with no Lapp marks or orange peel. You can try adding thinner to what you are using along with a retarder and lower your pressure and increase the liquid. Try to move a little slower increase your over lap. Hvlp guns tend to spray paint in the middle of the fan and the edges of the fan are air and dry lacquer. This creates the bounce over on your previous pass. Hope this helps
 

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Lacquer is a very easy finish to spray. Sounds like you have too much air pressure at the gun. The HVLP guns I've used run much less pressure at the gun...like 10-20 PSI IIRC.

I would try this. Add some retarder. It will allow a better flow by delaying the dry time. Instead of using a straight retarder, you could just pick up some "slow" lacquer thinner, and thin your mix. But, I've not used a lacquer that worked best "out of the can".

Basically to get more output, the air should be reduced, and the fluid control increased. You may have too large of a pattern, which can reduce the concentration of the spray. Or, too far from the subject. Or, too slow or too fast of gun movement. And for improving your finish would be to have a lot of light on your subject matter, so you can see the "wet line", by have a glare from it.






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I especially agree with getting a lot of light on the project. You may not be getting the overlap you think you are getting.

Set up a place where you can lay down a sheet of builders paper that is as long as your project and lets you spray your finish just like you would have to do on your project. It looks like Kraft paper and goes for about 10 bucks a roll at HD. You should get a good picture of your spray pattern because it will give you good contrast.

Orange peal and dry / rough may mean the finish is drying before it can level, if so, retarder should help. I wonder, though, if you aren't picking up some dust from your environment. Horizontal surfaces can be like dust magnets. If you are using a tack cloth between coats, you may be leaving varnish behind to mess up your finish. Remove the sanding dust with mineral spirits and then wait until you are ABSOLUTELY POSITIVE that it has completely dried before you apply the next coat.

I agree that lacquer is an easy finish to lay down.
 

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Discussion Starter #7
Thank you to all of you for taking the time to offer assistance with such great advice. I look forward to trying out the suggested techniques tomorrow after I have picked up some retarder. Heat could be a factor since I am in Hawaii. Would you suggest a certain ratio of retarder?
 

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Thank you to all of you for taking the time to offer assistance with such great advice. I look forward to trying out the suggested techniques tomorrow after I have picked up some retarder. Heat could be a factor since I am in Hawaii. Would you suggest a certain ratio of retarder?
I normally thin the lacquer with lacquer thinner ready to spray and only add about a tablespoon or two of retarder per qt . Retarder is also helpful spraying lacquer in humid weather. When the humidity is close to 70% the lacquer will dry cloudy. It's caused by moisture in the air getting trapped in the finish. It's called "Blush". A retarder thinner will slow the drying time down to where the water can get out of the finish before it dries.
 

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Hi all. This is my first time on a forum like this and I am relieved to have found it. I am having a lot of trouble getting a smooth finish on a dining table top. I've been spraying an M.L. Campbell pre-catalyzed lacquer through a relatively new Earlex HV7000 hvlp turbine spray system. I have had to sand off 4 failed attempts at a top coat. I am getting either a rough dry coat or orange peel . No happy medium seems to exist. The smaller test pieces come out smooth yet no luck once I move to the table. I've tried thinning the lacquer by 5% and also using no thinner at all. Should I thin it at a greater ratio? Have also tried with a 1mm needle and a 1.5mm. Also cannot seem to eliminate brighter stripes on the surface even though I am doing a 50% overlap. Feel like I've tried everything. Would love some suggestions.
Thank you.
i spray lacquer all the time i use the same M.L.CAMPBELL lacquer you use, i dont have the turbine system , just the HVLP gun, i have a 2mm nozel and i use 30 lbs of air , i have not problum's sometine's i thin about 10 percent , spray from you to the edge , not from the edge to you, you don't want the spray to fall back on the coat you just sprayed , other than that ? I use a sanding sealer, than 2 top coat's and done, I wait maybe 20 min between the sanding sealer and sand down to 400, and make sure to wipe down or blow the stuff off, than i spray the first coat, than i wait maybe a hr. than spray the other coat, and i am done, i let it cure over nite , that what i do, good luck check the nozell and air preasure
 

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Discussion Starter #10
success

thanks to all of you for your great suggestions. I thinned the lacquer to 40% and had success. Still going to look into other spray guns though.
 
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