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How to Prep for a Flawless Painted Finish

Jun 22, 2016 | Expert's Corner | 0 comments

While we may think that applying a film finish such as lacquer or polyurethane over natural wood can be a challenge, here’s a much tougher one: achieving a flawless painted finish. Blemishes in a clear film finish are disguised by the color and grain pattern of the wood. There’s no such hiding place with paint. Light playing across a painted surface only draws attention to any surface defects – and any pattern of wood grain showing through paint now becomes a defect instead of a feature.
As with most things, there’s good news and bad news about this. The good news: you can achieve a finish so flawless that it looks as if it belongs in an automobile showroom. The bad news is mainly for the “I want it finished NOW” crowd: doing this right takes time and patience. But that’s about as bad as it gets, so even if you’re a touch on the impatient side you may find this isn’t too hard to bear.
Whatever kind of piece you’re building – whether it’s free-standing or built-in – it’s almost always easier to finish individual components before they’re assembled. For a paint finish, that means filling, sanding and caulking all surfaces so they’re dead flat and free of imperfections before the paint goes on. It also means filling, puttying and sanding every single joint and crevice. The tiniest hairlines will look like the Grand Canyon once paint is applied. Paint won’t flow into the cracks so they’re as obvious as if they had searchlights turned on them.

As a result, your prep starts with filling the surface of every component so that it’s absolutely flat. You can use a spackling compound to do this, but for larger areas a light drywall finishing compound may more economical, plus it sands well. Apply the compound using a 3-inch wide putty knife, and then remove as much as possible using the same knife. DAP latex caulk can be handy when trying to smooth curved or textured surfaces. You can use your finger to apply it and it’s ideal for filling nail holes in moldings after an installation.

A low, raking light across the work surface will show up hills and valleys as you sand the first application of filler. Bright and portable shop task lights work well for this. Once the first application of filler dries that raking light will show where you need to fill or sand a bit more. You will need a second application of spackle or filler; you might need a third. Be sure to use a sanding block so the surface stays level when you’re smoothing flat panels. Cork glued to a hardwood block is ideal for this job. Joints between components are best filled with a thin, flexible putty knife.

A while ago I noticed that none of the newer putty knives I owned did as good a job as an old knife from my grandfather’s tool chest. I habitually reached for it because it was better at forcing putty or filler into joints than any new knife I had. The secret, as it turned out, was drop dead simple: the old blade had been worn to an ultra-thin and flexible edge, allowing it to go where no knife had ever gone before. A bit of time spent honing the blades of newer knives soon improved their performance until they were on a par.

You really must be meticulous about filling. Carefully fill the joint, packing it with putty or spackling compound using your new improved knife, and then use the knife to remove all excess filler, leaving a clean right angle. Small artist’s palette knives such as a small set from Lee Valley Tools ( part no. 35K09.01) can come in handy.

You want any corners to be square, not rounded over with caulk so they look as if they were coved. If all is not perfect after the filler dries, any bits standing proud of the surface can be smoothed using a piece of folded P400 grit wet-or-dry sandpaper. Any remaining valleys must be filled with another application of filler, again taking care to keep all corners sharp and square.

I have to emphasize that if you’re in a rush, this prepping and filling will make you crazy. But if you’re impatient it will show in the final result, so take a deep breath and try to chill. Rome wasn’t built in a day, and a top quality paint finish can’t be done in a day either. If it’s Tuesday and your clients expect the job to be finished by Wednesday, you’d better have a chat with them. Whether the pressure on you is external from a client or internal nederlandsegokken online casino from your own impatience, the only result from rushing and cutting corners will be a lousy final product.

Always set aside adequate time to simply look at the piece to be delivered or installed. It’s remarkable how many little imperfections jump out at you when you take the time to look a piece of furniture over carefully, seeing it from different angles or with different lighting. Now is the time to fix them. Meanwhile that little voice in the back of your mind will be telling you, “Okay, オンライン カジノ that’s good enough. The paint will cover the rest.” Ignore the temptation. The オンライン カジノ paint will not online casino gids cover the rest; it will highlight it.

Take great care to mask and drape all areas near the work for any on-site job where you must paint after installation. Neither a client nor your spouse will be impressed with paint overspray dusting their artwork and upholstery, so do be thorough. If you have to mask around hardware that cannot オンライン ブラックジャック be removed before painting, here’s a few tips to help you get neat results.

First, use a good professional quality masking tape. If you’re unsure of what to buy, call a paint retailer who supplies the trade and ask for their recommendation, telling them the type of paint you will be using. When you apply the tape, burnish its edge down with your fingernail. Before removing it, score all around its edge with a razor blade to cut through the film of paint, leaving a precise edge. This is especially important with latex paints which tend to be more elastic and will tear, leaving a ragged edge when the tape is removed.

A good way of protecting hardware is first to mask around it but with the tape applied to the furniture unit, leaving the hardware exposed. Then apply a thin coat of Vaseline to the hardware, covering it completely, and remove the masking tape. Spray the article, including the hardware, and then once the paint has dried, wipe it and the Vaseline off the hardware with a clean rag or paper towel.

Once you’ve done your best job possible with surface prep, the final, most revealing coat of filler goes on: your first sprayed coat of primer. This is really the acid test. With the primer dried hard, use your low lighting to inspect every panel, edge and corner with light from all directions. Fill any low spots and then sand all imperfections smooth. Lightly wipe down all surfaces with a tack cloth to remove dust from the sanding. Use your compressed air line to blow dust out of any corners.
The best way to make a final inspection before your finish coats of paint go on is to lightly buff all surfaces with a broken-in piece of the P400 sandpaper. By broken in I mean sandpaper that has already been used to smooth the back, bottom or inside surfaces of a project so it doesn’t cut as aggressively as new paper. A gray Scotch-Brite® pad or a pad of 0000 steel wool also work well for this final light once-over, and are a better choice to use on any edges to avoid cutting through the primer.

Be methodical and meticulous. Look at each panel and frame, turning them over, checking the edges. As I mentioned earlier, spraying will be much easier if any individual components of a piece, such as doors or drawer fronts, are painted separately before assembly. I support these pieces on nail boards or with small finishing nails tapped into their edges so they can be maneuvered easily.  Also, if you can paint them horizontally, you’ll reduce the risk of runs and sags in the paint. Once done, I remove the nails, fill the holes they leave, and then use a fine artist’s brush to apply a couple of coats of the final color over the filler.

(“Painter’s Pyramids” – little plastic pyramids about 2” in diameter – are being widely marketed as a means to support components during finishing. I always found that a few brads driven through a piece of plywood worked just fine, but by all means get the pyramids if they’ll make you happy.)
You’ve probably gathered by now that prepping for a paint finish is quite a bit of work. It isn’t all that hard necessarily, but it can be repetitive and tedious. To avoid the trap of “close enough is good enough,” budget enough time so that you can walk away from the project when you need to, take a break, and then come back to it with fresh eyes. Just a few short breaks when your patience wears thin is usually all it takes to get back on track. And with this work, patience is more than just a virtue; it’s the real secret behind – and underneath – a super paint finish.