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Applying a Lacquer-Based Finish


It is frustrating to turn a bowl or hollow form and then have trouble

getting an acceptable finish.  This was my experience when I first

started turning.  I could use the tools to shape the piece, and, given enough time, I could get the sanding done.  But yet I was reluctant

to offer anything for sale or even as a gift because the finish was

usually mediocre at best.  A poor finish essentially ruins the piece.


My initial approach was to keep spraying on additional coats of

lacquer, thinking that the finish must improve with each coat.  But

this was not the case; the finish usually got worse.  


The breakthrough came when I learned how to prepare the surface

for the top coat and how to use the Beall buffing system.  I also

learned what buffing cannot do – it will not remove wrinkles and

large blemishes from a finish, and if a finish is piled on too thick,

buffing will not make it appreciably thinner.  However, if the finish

is properly prepared, buffing will work wonders.


In the following, instructions are given for applying a high-gloss,

lacquer finish the way I do it.  The process goes in a series of steps,

and I don’t move from one step to the next until a satisfactory

result is obtained for the one I’m working on.  This way, I can be sure that the overall process is going to be successful.


This is not a quick procedure.  Because of the time that must be allotted for the various coats of finish to cure, the overall time span may be a week or more.


Sanding.  All tool marks and sanding scratches must be removed

before putting any finishing material on the surface.  A detailed

description of the sanding process is given in the articles on sanding. Check the articles index.

  

Brush on lacquer sanding sealer after the sanding is done.  

Applying sealer with a brush floods the surface.  The liquid penetrates

into the wood as opposed to quickly drying on the surface as a

sprayed material is prone to do.  I usually apply the first coat of

sealer while the piece is still on the lathe.


If the wood is even slightly degraded (spalted), the surface is likely to have tiny pits and regions of soft wood that soak up the finishing

material.  Applying the sealer with a brush gives it a better chance of flowing into and filling the pits as well as saturating the soft spots.  

Many coats of spray would be required to achieve the same result.


The disadvantage of using a brush is that brushing always leaves

brush strokes on the surface.  You can do two things to minimize this. First, thin the sealer (with lacquer thinner) so that it will flow out

before drying.  I find that thinning from 20 to 30 percent works best.

More importantly, use a good quality, fine-bristle artist brush that’s

about 1” wide.  A red sable brush is probably the best.  


Evaluate.  After the brushed-on sealer is dry enough to handle,

examine the surface and decide what should come next.  If there are

pits still showing or if the sealer has completely soaked into the wood

in some regions, a second brushed-on coat may be in order.  


However, if you are working with good, tight-grained wood and the

surface is completely covered by a film of sealer, you may elect to

spray the second coat of sealer instead of brushing it on.  This will

avoid producing a second batch of brush strokes that would then have

to be sanded away.  


Either way, you must now make another decision.  Does the surface

need to be sanded (with 320 or 400 grit) to smooth the surface before applying the next coat of sealer?  There may be dust nibs or other

tiny, prickly things on the surface, or prominent brush strokes which should be removed. If you decide to sand, put the piece aside for

another hour or so to let it cure enough so the sandpaper will not clog. Otherwise, go ahead and apply another coat of sealer.


Only very light sanding should be done at this stage because the film

on the surface will be thin. It’s easy to sand all the way through to the wood, which is a step in the wrong direction.


This process is repeated as many times as necessary to build a film

on the surface that is smooth, continuous, and free of pits.  I

typically apply three coats of sealer, sometimes more, with the last

coat or two being sprayed.  This is to ensure that the film is thick

enough to sand in the following step without the risk of sanding

through to bare wood.  


At the end of this process, set the piece aside and let the finish cure

for at least 48 hours in anticipation of the final sanding.  


Sand to obtain a uniformly dull surface.  The objective at this

point is to obtain a perfectly smooth surface that will be sprayed with lacquer.  This is done by sanding with 400 grit to obtain a surface that

is level and uniformly dull. If the surface is particularly rough,

relatively speaking, you may begin sanding with 320 and then finish

with 400, to save a bit of time.


As the sanding progresses, you will probably observe striations of

dull and gloss as the high points of the surface are leveled.  Keep

sanding until all the glossy regions are gone and only a very thin,

dull film of sealer remains.  If the thickness of the film is observable,

it is probably too thick and should be reduced.  


Spray the piece with high gloss lacquer.  Only a very thin film of lacquer is required when the surface has been prepared as described above.  The first time you try this, you will almost certainly apply too much.


Do not spray on enough to make the surface look wet and shiny.  Two

or more very light coats will give better results than a single coat that

wets the surface.  An additional coat can be applied after the first is

dry to the touch.  Do not stand the surface between coats.  


Spraying a coat that’s too heavy can lead to problems with orange

peel.  This happens when the lacquer does not flow out smoothly

over the surface and gives an effect that looks like the peel of an

orange.  If you get it, the surface will have to be sanded again.


Keep in mind that what we’re doing at this point is preparing the

surface for buffing. The buffing will add the shine. If you build up an observable thickness of lacquer, the surface may wind up looking like plastic.  


If you mess up, you must let the finish cure before doing any sanding

to remove sags, runs, or orange peel.  Pure lacquer does not sand

nearly as easily as the sanding sealer.  The best option is to let the

piece sit for several days before coming back to do the sanding.  


Let dry and then buff.  After the lacquer is applied, let it cure for a

day or two before taking it to the buffer.  If you attempt to buff

before the full thickness of the finish has cured, you can buff through

the top layer and get patches of smearing and streaking.  This is a disaster; you have to sand it back and start over with the top coat.


Details of the buffing process are given in the article on buffing.


Cleaning the brush is easy.  After brushing on a coat of sanding

sealer, you have to clean the brush. It’s easy to do, and takes about 30 seconds.  


Simply blot as much sealer from the brush as possible by squeezing

the bristles inside the crease of a folded paper towel.  Don’t pull on

the bristles as you do this; they may come out.


Then swish the brush in lacquer thinner.  Again, squeeze the bristles

in a paper towel to remove most of the thinner.  Finally, run a finger across the end of the bristles to fan them out so they don’t dry

together in one hard clump.  And that’s it.  


The next time you go to use the brush, dip it into lacquer thinner and

it will soften and be ready for use in just a few seconds.


Variations.  There are many other methods being used to apply a

lacquer finish.  The one described here is what I use, primarily

because I work a lot of crappy wood and the method allows me to

build the finish in a series of steps.  If I get a good result with each

step, the final finish will be good.  


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