The problem with spraying Deft brushing lacquer is that they put retarded in the brushing lacquer to keep it from drying too fast. When brushing it, you want it to flow out before drying to get rid of the brush marks. That makes it more difficult to spray on a vertical panel - it runs unless you're very careful.
Even on a horizontal panel, it takes longer to dry which means more time for junk to settle on it.
But I have to question why you want to use lacquer. If you're doing cabinet door panels for a kitchen, for example, why not spray polyurethane? You can even use water based poly. The advantage of poly is that it holds up better in wet. You might say, "But these are doors and they won't get wet." What happens it that people have wet hands from the sink and they open the cabinet doors. The top of the door (on the bottom cabs) starts to wear out from the constant wetting.
But if they're your doors, and you know what's happening, just sand the top of the door lightly every couple of years and brush (or wipe) on more lacquer. Where that fails is if you stain the doors. Every time you sand them, some of the stain comes off and it gets noticeable.
Anyway, I like lacquer for furniture that doesn't get a lot of wear or wet and poly where you have wear, heat and/or wet. Also, if you're looking for a real high shine, lacquer rubs out much better than poly.
So they both have their places.
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