# Hvlp lacquer first try - what's going wrong



## sammy.se (21 Mar 2015)

Hi

My first go on HVLP spraying, using morrels 40% waterbased lacquer. 

not a good first attempt to say the least. I used it neat, and these were the results. I was expecting an even, smooth covering, but got this instead. This is the first coat. Any ideas on whats going wrong?

It's a 1.6mm needle, on an earlex 4000.

Thanks


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## sammy.se (21 Mar 2015)




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## sammy.se (21 Mar 2015)




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## sammy.se (21 Mar 2015)




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## mailee (21 Mar 2015)

I don't use water based lacquer myself but from what I can make out on the pics it looks like the paint is too thick. Your first pic does show far too much build on the lacquer which means it needs thinning a little and the flow control needs turning down slightly. Did you also make sure the timber was clean and free of any silicones? I can't make it out in the pics but are those fish eyes in the finish or is it bubbles? As I state i do not use water based only solvent so I could be mistaken. HTH. :wink:


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## sammy.se (21 Mar 2015)

Thanks mailee. I will try thinning it down. I dont think there's any silicone - it's wood dyed, then steel wool. 

It's definitely not bubbles, its little droplets (is that fish eyes i presume).

Am I right to be expecting a smooth finish on the first coat?


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## niagra (21 Mar 2015)

I use waterbased paint with an Earlex. My first results were similar. I haven't found the need to thin down the paint at all, the stuff I use is very thin already. Just turn down the pressure quite a lot and do a lot of thin coats, recoating every few minutes or so and spray closer than you would do with a rattle can. I'm no expert, but I've had fairly decent results like this.


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## n0legs (21 Mar 2015)

The material is too thick, insufficient atomisation.
Thin the lacquer down, reduce the flow through the fluid tip [wind the screw in] and try lighter coats. 
Keep the gun about 8-12 inches from the workpiece, moving at a steady rate across it. Overlap each pass by 50%.
Pin some paper up an test the gun setup and lacquer mix on it first. 
Don't be tempted to rush. When spraying application is quick but preparation can take a bit of time.

Your last pic isn't so bad for coverage bu the laquer hasn't flowed out, hence the surface appearance.
Don't give up or get disheartened with it, apprentice painters learn for two years, it's just practice you need.
Good luck.


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## RobinBHM (21 Mar 2015)

Although you may be able to get a reasonable fan pattern with unthinned lacquer, the coat wont flow out and will dry as per your first image.

Alomost all lacquers will need thinning before spraying, especially through an hvlp set up. I would buy some 600ml mixing cups and then thin the material by ratio. Water based materials should only be thinned by a maximum percentage but I would try between 5% and 10%. Although its tempting to slosh a bit of water in and spray, I would recommend doing it somewhat methodically and measure out accurately and record what you do, so once you get it right you will be able to repeat the set up.

Experiment with spray-outs on some card or wallpaper etc. I would never go straight to the work, a spray-out will always tell you if the set up is right. Its useful to start by having the gun stationary and trigger the gun, this will tell you if the fan pattern is the correct shape and help with establishing distance. Once happy with that, spray a horizontal stripe and check wet film and see if it flows out nicely. Once happy with that try a spray-out over an area, over lapping by 50% and look at the result to see if your overlaps are giving an even coverage. When spraying an item remember the first pass with the gun needs to be with the gun almost in line with the edge, so you achieve a full wet coat right to the edge of the work.

Its also valuable to keep checking your sprayout as it dries so you can see how the film changes as it flashes off -a coat too thin will have dry patches, too wet and you will see runs develop at edges, too thick and you will notice the coat does not flow out and the finish dries as orange peel

I find spray-outs are actually best done on a smooth surface like an offcut melamine faced chipboard, it will make it easier to see the film build and more like your second coat would be. Its difficult to see the quality of the wet film on bare timber as the film is soaking in as you spray.


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## sammy.se (22 Mar 2015)

Hi all, thanks so much for the detailed responses and advice. Ill try again this evening/tomorrow and share the results


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## Mike.S (22 Mar 2015)

I'm an inexperienced sprayer but having sprayed Morrells lacquer with an HVLP I'd like to share a couple of thoughts. 

I found the Morrells doesn't need any thinning but did manage to achieve poor results, similar to your pics, by either spraying too close (therefore, lacquer has insufficient room to achieve the optimum spray pattern i.e. it's applied too thick) and/or by applying too many coats too quick. I'd recommend you try to find the right spray pattern and distance first, then flow rate (ratio of air to paint) and only then consider thinning.


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## kfenelon (10 Aug 2015)

Do not thin the lacquer place the plastic container in a bowl of hot water for about ten minuets and also make sure the work you are about to spray is not cold Then apply a mist coat followed by a full coat within 10 minuets if you allow the mist coat to dry hard nibb the surface using an Abralon pad 1000 grit as you only require a very fine nibb to the surface.


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## Roughcut (12 Aug 2015)

Even though the post is several months old here's my two pennies worth:
Pre-warming the laquer or paint especially when the ambient temperature is cold should help.
Regarding the Earlex adjust your spray fan pattern first so that you are spraying in a vertical or horizontal pattern depending on the object you are spraying.
I usually wind the paint volume knob in until it's closed and then gradually back it off and open it up while test spraying a piece of scrap material until the correct amount of paint is coming out of the gun.
Holding the spray gun 6-8" from the piece being sprayed seems to be about right for getting a nice even coat on while moving along at a steady pace.
Spraying too far away can have an effect on the atomization of the paint/laquer and cause paint runs and an uneven finish.


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