After the guitar has 5-6 coats of lacquer applied, allow it to cure for a week before sanding with 320, 400, 600 and, maybe, 800. At this point, if one wants a matt (satin) finish, you could be done.

     If a glossy finish is the objective, there is still another step… buffing.

Step 6:    SEAL & SAND

    This is the 13th and last chapter of Overview installments, thus completing the Home-Shop Guitar Building 'Book'. Step-by-step guitar building presentations have been posted here each month since last June. 


      Woody has, more than once, referred to 'Finishing' as 'Starting All Over!’. The tools of finishing are different. The skills required are different. The shop itself is different and should be located in a different space separate from the guitar-building shop. A few years ago, Woody built a backyard shop specifically dedicated to finishing.

         All of this, as well as the details of applying a lacquer finish to the guitar, will be explained here. It has taken many words and photos to explain the 'starting all over' process. Get comfortable.


EPILOGUE Comes Later
    The subject of the next post will be the refinishing the sunburst of the ES-125 pictured below. It will take a while to get it together. 
    

Step 3:   PREP

                There are several steps to complete after the guitar is assembled. These steps are necessary to make the instrument ready to be sprayed (or brushed) with vinyl sealer and nitrocellulose lacquer.

      Final Shaping and Setup:     Final Shaping of the neck is done at this point, if it is needed. Woody also likes to string up each guitar, set it up and play it before spraying the first coats of sanding sealer. This way I know the feel of the neck in the musician's hand... before nothing can be done about it.

      Cleaning the Guitar:     During the guitar building process, the guitar is kept as far from damage and dirt as possible. In a small shop it still gets dirty and occasionally dinged as it nears completion. A first step in the finishing process, therefore, is the cleaning and final sanding of the entire instrument. This shouldn't take more than a couple of hours if one has been careful along the way.  There are always tooling marks and smudges that need to be removed.

     To clean a bare-wood guitar of surface oils, acetone is reliable and effective... and leaves no residue or smell. A caution is needed, however, with the use of acetone on rosewood.  Acetone will draw the oils out of rosewood which will stain any lighter colored wood (like maple bindings or perflings). This staining is one of the reasons that most guitars have plastic bindings these days. Woody, of course, finds wood bindings to be preferrable. So, I make the effort to keep the bindings clean and use no wood stains of any kind on the guitar if possible.

     Masking:   The last step before spraying is the masking of the parts that are not to receive lacquer.  This includes the fretboard, the bridge, and the sound hole.  When masking the fretboard, be sure to snug the masking tape tight around the end of each fret. Otherwise, there will be a little mess of lacquer that creeps under the tape and onto the ebony or rosewood at both ends of the fret.

     The five guitars shown below are ready for spray except for the masking of the sound hole from the inside to keep lacquer out of the acoustic box. Usually, I stuff rumpled newspaper inside the box and that presses a circular cardboard cutout against the sound hole from the inside.

​​To Be Perfectly Clear...

     The instruments that Woody builds are (unless the client insists) finished without wood stain or toners.  That is, they are finished with only clear lacquer sealer to fill wood pores and clear lacquer on top, back and sides. As a result, the various woods appear in their natural colors. Because Woody prefers wood bindings, stained filler and/or stained surfaces complicate the finishing process unnecessarily.

      An extra coat (or two) of clear vinyl sealer, fully cured and sanded down, will fill the wood pores adequately. The result is that the application of the finish has one less concern to worry about, i.e., wood stains bleeding into the light-colored, wood bindings (like maple), which are a favored characteristic of Woody guitars.

      The tradeoff is that every hand-tooled joint and/or cosmetic imperfection is 'clearly' visible. For some people, slight cosmetic issues would not be acceptable, for others, it is further verification that the instrument is unique, and hand made. For the luthier, clear finishes are added incentive to keep the building process clean.

    Appropriately, all 'Woody' instruments, have a clear, lacquer finish that displays the natural tone and beauty of the wood. The only exception is the rare sunburst finish that Woody applies by special request. More on that in the ReFinishing segment in the final chapter.

​​Q&A    

     Often, the more questions one has about finishing, the more confused one becomes when searching for answers online. Don’t panic, everyone feels this way.  Finishing requirements are different for every shop and every project. You will have to pick and choose ideas that will work in your shop.


THE BEST INFORMATION:    I have found that the most reliable information comes from individuals in live presentations like at Woodcraft Supply or comparable local wood/hardware or finishing shop

Finish Surfing

     Much on-line finishing information is found in internet forums.  Some of that information, however, comes from people who know less than you do… still, they post recommendations as if they come from stone tablets recently unearthed from the Dead Sea.

    Other on-line information comes from people who know waaaaay more than you do … but they are generally not luthiers. Furniture requirements are similar to luthiery requirements, but different. All of this is OK if you can sort the wheat from the chaff.  Bear in mind that the limitations of your shop in regard to space, ventilation and equipment will make the biggest impact in one’s choice of methods.

     e.g., The first several years at Woody Strings (1976), I applied lacquer only with a brush. Why? Because I did not have the equipment or space to spray lacquer… and I was living in Fairbanks, Alaska. Woody Strings was a rented space inside a retail music store. I had to brush on lacquer after store hours.

     For brushing there is a special formula ‘brushing lacquer’ which can be purchased by the gallon. With a lot of shoulder work sanding the finish flat between coats, and thinning the lacquer mix as one progresses, good results can be achieved (but not recommended here). 

     The compressor is the heartbeat of the finishing system. In choosing a compressor, it's a good idea to avoid oil-lubricated machines in order to reduce the chance of fouling the tank, air lines, and gun with oil. In-line filters are a good idea. When shopping for a compressor, be sure to know your gun's air delivery requirement and the air delivery capabilities of the compressor. That information is a nameplate standard and in the machine specs, i.e., xx scfm at 90 psi and xx scfm at 40 psi. The smallest compressor one might use in setting up to spray guitars would have at least a 10-gallon tank and deliver at least 6 scfm at 40 psi.  (scfm = standard cu. ft. per minute) Check the nameplate.

​​     Another point to be aware of with compressors is that they are often driven by large electric motors (3-4 hp or larger).  The nameplate amp rating is a good thing to check. It will be written something like 15.0/ 7.5A (see above).

     The 7.5 A is the running amp requirement, and the 15.0 A is the in-rush amp draw. When the compressor is first turned on, it spikes the power supply (in-rush) in order to get the motor spinning and up to speed.  If the compressor is on a normal residential 15-amp circuit it could trip the breaker every time it's turned on. It may need a dedicated 20-amp circuit and require a 12-awg extension cord. Think about it.

 USED COMPRESSORS

     When buying a used compressor, these are just a couple of things to check. Was the tank routinely drained? (to keep condensed water from rusting the inside of the tank) Is the intake filter intact and clean or easily available for replacement?  Do I have an electric circuit that I can dedicate if needed? Are the tank and spray volumes adequate? (Recommend at least 8.0 cfm @ 40 psi and a 12-gallon tank)

 ​     After 2 or 3 coats of sealer have been sprayed and allowed to cure for a couple of days, the guitar is ready to be sanded flat to ensure that the pores are filled.  Woody uses the sealer as a filler because 1) it is clear and 2) wood bindings pick up stain from wood fillers.  Woody, as one might expect, likes the look and feel of wood bindings (usually maple, as seen below). No wood stains are used on Woody guitars (unless it is a rare sunburst).

     After the sealer has been sanded flat there might be some spots where the 320-paper sanded though to bare wood. That’s a problem that you don't want but can overcome. One final coat of sealer sprayed on the entire guitar will set you up for the application of the lacquer… usually 5 or 6 wet coats applied over 2 or 3 days. Some luthiers apply more lacquer, some less... luthier's choice, but spray and sanding techniques are the same whether it's sealer or lacquer that you're spraying or brushing on. The objective is to have a finished surface without orange peel or sunken grain pits... smooth and flat.

Step 8:    BUFF

     Pictured is the Stew-Mac ¾ hp buffing machine.  To one wheel Woody applies a medium buffing compound and to the other apply a fine buffing compound.  This machine is not cheap. Woody bought this a couple of years ago for about $600 (I think) and that was without the ¾ hp motor which I already had.

     This is a great machine and has saved old Woody many hours of rubbing guitars by hand to make them shine. I have wanted something like this all the way back to my Fairbanks days. Pictures are truly worth a thousand words.

     Woody’s ‘shed’ is designed, organized, and maintained to be a guitar-finishing space primarily.  It also has two workbenches set up for miscellaneous projects as needed. Woody has made it a point, however, to NOT let these 192 sq. ft. become a storage area for family junk.

     The shed pictured below is 12'x16' and was built for spraying lacquer. It cost less than an actual spray booth and it is much more versatile. It has two work benches and tools for miscellaneous luthiery tasks and teaching when not spraying lacquer.

    Woody tries to keep the shed organized, clean and free of dust during ‘finishing’ season.  Because there is no temperature or humidity control, the shed is used for spraying lacquer only when the temperature is above 60 F and the relative humidity (RH) is below 55%. That translates to a few hours in the afternoon on about half of Virginia’s spring and summer days.

     The shed is ideal when the ambient conditions are right. Guitar finishing is tedious at best, and a dedicated work space has helped significantly. (and it has added to the value of my home)

Step 4:    SPRAY

 ​     Imagine this: You are wearing your 3_M, volatile-compounds spray mask; the compressor tank is pressurized (regulator set to ~30 PSI); the spray gun cup is full of lacquer; the spray pattern has been tested on scrap cardboard.  NOW, you are ready to spray. The objective is to lay down an even layer of lacquer over all parts of the guitar that are not masked.

     The guitar body is sprayed first.  Holding the guitar by the neck with the left hand, (as shown below) will put the body of the guitar directly in front of you.  It is important to maintain the same distance between the spray gun and the guitar while spraying.ALTERNATIVE: One can hang the guitar with a Woody Strings Hanger Gizmo* (or similar) and spray the whole guitar while it hangs vertically in front of you. 

​​The Wait

     Finishing requires the application of several coats of instrument-grade lacquer. Woody applies two or three coats of sanding sealer wet sanded between coats. Then, 3-4 coats of lacquer are applied in order to build up a hard, durable finish. As the Woody shop is producing only a few instruments each year, I can afford to wait 12 to 24 hours between coats.  This allows more than enough time complete the chemical adhesion between coats. The worst thing one can do is to put on too much finish, too fast.  As I am only applying, maybe, a total of 6 coats, I allow a week to apply the finish. 

     Then the hard part... waiting. One should allow the lacquer to cure for a month before returning the hardware to the instrument.

​​Step 2:   EQUIPMENT & MATERIALS

The Compressor

     Pictured here is a good, but relatively inexpensive, 4 hp; 15-amp compressor that can deliver 8.8 cfm @ 40 PSI; with a 12-gallon tank. This compressor is about as small as one can get by with for spraying lacquer and/or sealer.

      The 15-amp rating is the in-rush current requirement (when it starts up). A dedicated circuit is a good idea.

Step 7:    CURE

Materials    

     A quality vinyl sealer; musical instrument lacquer; lacquer thinner; a quality retarder; and acetone are essential chemicals for spraying instrument-grade lacquer.  Different brands for different folks.  Mohawk/Behlen have always worked for Woody.

PolyUrethane

     A few words of explanation:      Polyurethane is used on many guitars sold in retail stores.  Of course, plywood guitars are also sold in retail stores and online and these, almost invariably, have polyurethane finishes. Polyurethane is not suitable for a solid-wood guitar, in my opinion. It's just too hard and inflexible. If one is buying a plywood guitar the buyer is probably more interested in cost than in guitar resonance. Hand-made and high-quality manufactured guitars deserve much better.

     Instrument grade lacquer is made to be flexible and that is what large, resonating, solid-wood surfaces (like guitar tops) need. Polyurethane is hard...very hard... and, for one thing, impossible to repair. Guitars are large, lap instruments and difficult to keep from bumping and scratching occasionally. The extreme hardness of polyurethane is good for the rough lifestyle that almost all guitars must endure. That hardness, however, is a double-edge sword. It seriously inhibits the flexibility of the guitar top and the sound of the guitar.
     Resistance to change in humidity is not the purpose of the finish. The finish should protect the exterior of the instrument from damage while minimizing the dampening effect on the transfer of sound vibrations through the wood. For a guitar, minimum sound dampening means using instrument-grade lacquer.

      Unlike polyurethane, lacquer finishes continue to shrink over the life of the instrument and this is one reason why guitar tone improves as it ages. My experience is that the tone of an acoustic guitar does not fully 'mature' until both the wood and the finish of the instrument are 10-15 years old. I will never advise refinishing an old guitar. Restoring the day-it-was-built look will come at the loss of sound quality. This type of restoration is contrary to Woody's perspective that a guitar is to be played and enjoyed for its sound, and admired as a museum piece... well... Later.

​​Ventilation

     If your 'spray booth' ventilation system is the same as your home HVAC system... forget it. To spray 6-8 coats of lacquer and sealer on a guitar, one needs to take it away from the air that you and your family are breathing (i.e. take it outdoors).  Be mindful of humidity and bugs and you will be OK. Inhaling finishing fumes while you're sleeping is not OK.

     When spraying lacquer, WEAR A MASK. This is not optional. The damage that you can do to your lungs very serious. We are talking here about a commercial, volatile-compounds mask as pictured below. It comes with charcoal filter cartridges that can be easily replaced.

     When spraying, the guitar is always hung, as pictured, directly in front of the double-door entry to the shop. Overspray, therefore, either goes directly to the outside or is blown out as a window fan on the opposite wall blows air into the shop creating a positive pressure which forces everything that is airborne (including tiny bugs) out the double doors.     


     Lacquer fumes and overspray never pass through the fan.

Step 5:    CLEAN

June, 2021

Chapter 14_ FINISHING
 

​​Step 1:    SPACE 

     The finishing process is not very technical but the skills required are entirely different from the wood working skills of shaping and joining wood. Spraying finish requires a dedicated finishing space that is well-lighted and, importantly, ventilated by something other than the same HVAC system that heats and cools your home. If not, lacquer overspray and off-gases will be carried into all parts of the house including the bedrooms and kitchen... not good. 

     Woody has looked into contracting out the finishing work, but most finishing and re-finishing shops are set up for furniture and don't have (or don't want) experience with musical instruments.

      All this is to say that a few years ago I spent most of April and May building what would be a ‘finishing shed’ in the back yard. The plan was to create a space that could be used primarily for finishing guitars.  If you ever wanted (or needed) to build a shed in your back yard, here is a good excuse.

​​​Begin with the End

      As always, begin with the end in mind. What are your preferences on this spectrum of importance? (ignoring cost for the moment)

                     Acoustics--------------------Shine

Acoustics:   The best sounding acoustic guitar would probably have NO finish, or a very thin finish.

Shine:   The standard today is an instrument that has a deep shiny finish. Shiny sells… especially to novice or first-time buyers. As a home-shop luthier, every guitar/client is different.  That’s part of what you offer.


FINISHING: NINE STEPS

       Step 1: SPACE
       ​Step 2: EQUIPMENT/ MATERIALS
  ​     Step 3: PREP
       Step 4: SPRAY
       Step 5: CLEAN
       Step 6: SEAL & SAND
       Step 7: CURE
       Step 8: BUFF
       Step 9: LISTEN  
 

Purpose and Scope


     The finish on an acoustic instrument cannot protect it from changes in atmospheric temperature and humidity. That’s what cases are for. The goal of applying a finish to an acoustic instrument is to seal and protect the outside of the instrument from mechanical damage. That is: dings, scratches, spills, dirt, and all of the above if you drive around town with your guitar untethered in the bed of your pickup.  

     Finishing a guitar at Woody Strings means spraying, leveling, and polishing nitro cellulose lacquer. For this process, Woody built a dedicated shop specifically for finishing.

 

Temperature and Humidity

   In the Southeastern US the ambient relative humidity is a serious factor in the application of volatile finishes like lacquer. Ambient moisture (humidity) in the air can become entrained in the lacquer spray and carried onto the guitar surface. This moisture causes blushing. ‘Blush’ appears as foggy areas in the applied finish.
     To avoid blushing, Woody adds about 2 oz. of retarder to a 24 oz. cup of lacquer.  Retarder slows down the cure so that moisture entrained in the spray can escape from the lacquer as it cures on the guitar surface.

     Moderate coats are best when trying to keep the lacquer from blushing.  The worst mistake one can make is to apply too much lacquer. When a heavy, double coat of lacquer is applied, even retarder can’t hold the lacquer open (volatile) long enough for the moisture to escape.  The final cure will appear to have a misty cloud in spots.


     Woody does not spray when the outdoor relative humidity (RH) is above 55%. From my observations, when the RH is below 55% and falling, that’s the best time to spray. In Richmond, VA the best months for spraying lacquer are in the spring and early summer. For the home-shop luthier, that might be only a few hours of the afternoon between 1:00 PM and 4:00 PM.
     Large manufacturers have the benefit of climate-controlled, well-ventilated finishing booths and curing rooms. For the most part, home-shop luthiers do not. There are major challenges, therefore, in a small shop... humidity and temperature control, as well as safe [A picture containing watch, gauge Description automatically generated] [A picture containing text, watch, device, gauge Description automatically generated] and effective ventilation.

​​​​     THE COMPRESSOR TOO. When finished using the compressor for the day, one should always drain the tank. This allows the moisture (H2O condensate) that has accumulated in the tank to drain out. Otherwise, rust forms inside the tank.

     Condensate moisture accumulation while one is spraying can be filtered with a moisture filter in the compressed air line. Also, be sure to maintain the intake filter on the compressor. If the intake compressor filter is broken or removed, dirt and water will accumulate in the tank and will eventually end up in your hose and possibly in your finish.

     Finally, open the drain cock on the bottom of the compressor tank.  Allow the air and water to blow out.  Leave the stop cock open until next time.

​​​The Finishing_ Shop Safety

   Spraying lacquer creates immediate safety challenges in the ventilation of overspray and fumes. Lacquer is extremely volatile and any spark in the spray area, such as from a compressor or fan motor, or fluorescent lights, can trigger a fire or explosion. I do not mention this casually or as an incidental. Safety precautions MUST be taken to avoid what could be catastrophe when spraying volatile liquids like lacquer.  If not properly ventilated, lacquer overspray will accumulate on the walls and ceiling of the spray area, and this is like painting the walls with nitro-glycerin. Small-shop luthiers have three choices:

•Build a dedicated space and ventilation system for finishing
•Brush finishes in a space with a dedicated ventilation system
•Spray outdoors
•Buy a completely equipped and inspected commercial spray booth and have it installed in a space that is NOT in your home.

     This Overview of guitar building is for home-shop luthiers. Commercial spray booths will, therefore, not be discussed here.

     Woody has used a combination of the first three of the options above and the results have been acceptable, albeit with considerable effort. The Finishing Shop, described below, was built primarily to move all finishing procedures out of the Wood Shop... which is attached to my house and on the same ventilation system. Safety first.


EPILOGUE Comes Later

    The subject of the next post will be the refinishing the sunburst of the ES-125 pictured below. It will take a while to get it together.


In the mean time...


Play Safe, Stay Healthy, 
    

The Final Forum

      All that being said, on-line information about finishing musical instruments can be found at several forums. (Re- Ranch; Ultimate Guitar; Acoustic Guitar Forum; etc.) I am not endorsing ANY of these… but they are a place to start.  Everyone seeks a process that they can understand and can afford. Pick and choose the information that applies to you and your shop.

    Woody’s notes and recommendations (presented here) apply generally to the home-shop luthier building less than a dozen instruments per year.

How Much Finish is Enough? 

      Acoustically, there is no reason to fill the grain, apply multiple coats of sealer, build and flatten the finish. It’s a lot of work and there is really no acoustic gain in making the top of the guitar look like the top of a bar stool.

     One or two finish coats over a sealer coat is completely adequate for a guitar that rarely leaves home. Such a finish might be called the ‘Cowboy Finish” which would suit me fine if my clients would ask for it… they don’t.

     The point is, in a home shop, the Broadway Finish could be 20 hours more work beyond the Cowboy Finish. Nonetheless, the deep, high-gloss finish has become the standard and what people expect. That process will be explained here.

Lacquer

     The guitars that one sees in retail music shops these days are generally finished with polyurethane (low end) or nitrocellulose lacquer (high end). Lacquer is the choice of most of the small, high-end instrument makers at present. Woody Strings uses Behlen or Mohawk instrument-grade, nitro-cellulose lacquer (or equivalent). What's "instrument-grade' lacquer?  It's more flexible than furniture lacquer. That's all that I want to say about that right now.

     Like most finishes, lacquer comes as a high-gloss or some grade of satin. Satins are graded according to their respective sheen (10, 20, 40, 60, 80). Number 80 sheen is Classic Instrument Lacquer clear gloss. 10 sheen is flat and 20 sheen as very low gloss matte, almost flat. 40 sheen is what Mohawk calls satin. 60 sheen is semi-gloss. I like to use 80 sheen for a full gloss.  If I am going for something a little flatter, I use 60 sheen...semi gloss. It's a personal thing. (See Mohawk Finishing Products)

​​     A gallon of instrument lacquer will cost $40-50... about the same as high-grade Sherwin-Williams paint.  BUT... they probably don't sell instrument-grade lacquer at your local paint shop so one has to order it (Mohawk Finishing Products, Asheville, NC) and pay the freight.  Woody's experience is that the freight charge is the same up to three gallons.  If that is still the case, one might as well buy three gallons and only pay freight charges once.

 

Step 9:     LISTEN 

     Overlap the spray pattern as you reverse course across the back of the guitar. When the entire back has been coated with horizontal strokes, some like to cross again with vertical strokes. If one feels it necessary to do this, be careful not to apply too much lacquer.  Applying too much lacquer is the worst thing that you can do.

     NOTE:  When you change from a horizontal to vertical spray path, be sure to change the spray pattern out of the gun from vertical to horizontal by rotating the spray cap 90 degrees.  The spray pattern should be across the spray path to avoid runs and drips. (i.e., spray path horizontal, spray pattern vertical)

​     Apply lacquer to the top and ribs of the guitar in similar fashion as described above, holding the guitar by its neck.  The sides of the guitar are sprayed crossways with a vertical spray pattern_ back and forth across, not up and down. Keeping the gun the same distance from the work surface is a challenge when spraying the guitar sides. The surface of the sides of the upper bout, the waist and the lower bout are all in different planes.  Again, holding the guitar by the neck, Woody sprays the ribs while changing the position of the guitar with one hand and squaring up the spray gun with the guitar surface with the other. 

     If one is a novice, this might sound tricky.  Actually, while one hand keeps a firm grip on the guitar neck, not allowing the guitar to touch you (or anything else), the other hand is moving the spray gun and overlapping the spray pattern, as necessary.

     When one becomes good at this, it becomes more art than craft. Learning to lay down an even coat takes lots of practice. Woody tolerates spraying and polishing lacquer finishes as a necessary evil. The only thing worse is having to strip the finish and do it all over again. That alone, is a good reason to take your time and do your best the first time.

​​​*Woody Strings Hanger Gizmo

          This little DYI home-shop gizmo works great for hanging and spraying a guitar.  When the entire guitar has been sprayed, the wire loop and dowels also give you a place to lift the guitar and carefully carry it to a place that is out of the way without hanging it by a freshly lacquered neck.


​     KEEP IT CLEAN:  Spray gun operation can be frustrating. Starting out I have this advice. Keep your spray system as clean as possible (spray area, spray gun, hose, compressor, etc.). This means putting air and water filters in line before the air reaches the gun and cleaning the gun after every use.  The degree of cleaning depends on what has been sprayed, how long it will be before using the gun again, and if one intends to spray the same finish and color.  Changing from tinted sealers or lacquers to clear top coats should be applied from an entirely different gun to ensure no surprises.

     No matter how clean you keep things_ bugs happen (meaning hair, dust, wood slivers, fingers). Be prepared to remove minor bugs in the lacquer immediately... before the lacquer begins to set. While the just-applied lacquer is liquid, it is gracious. Little digs and rubs can be blended with the next coat if applied immediately... i.e., while the present application is only beginning to cure.

      After a spray session, one should keep the spray gun clean in order for it to spray efficiently and in a predictable manner the next time.  It’s OK to leave the gun hanging with a half cup of lacquer for a few hours. Or, if you have a HPLV gravity gun remove the lid on the cup, pour out the lacquer into a clean jar, put a few ounces of lacquer thinner into the cup, and spray until the cup is drained. This will clean the nozzle.  It’s not a good idea to leave the gun loaded with lacquer overnight. *

     After the final spray of the day, clean the needle and nozzle parts with acetone (needle, nozzle, spray cap, cup, and orifices).  It takes less than 5 minutes, but it does require a small bit of disassembly. Also, blow out the orifices with an air nozzle while there is still pressurized air in the tank.

     Now, reassemble the gun and put a couple of ounces of acetone in the cup.  Spray the acetone through the gun until the cup is empty.

 * If you have a siphon gun, remove the half-full-lacquer cup from the gun and dip the intake tube from the gun into a small jar of lacquer thinner and spray thinner through the nozzle for a few seconds to clear any remaining lacquer residue in the nozzle. Then, re-attach the gun and the cup and hang it on the wall.


​​The Spray Gun

     Today there are HVLP (High-Volume, Low-Pressure) guns that deliver the finish more efficiently than siphon guns. That is, they deliver more volume (more lacquer) and require less air pressure.  These are generally gravity guns_ meaning the canister is mounted on top of the gun. Gravity guns also require less air to move the finish from the canister into the air stream through the nozzle. (i.e., gravity is helping).
     Another advantage with a gravity gun is greater ease in spraying at angles. It's best to keep the gun upright at 90 degrees to the work, but sometimes, that's not practical.

     Pictured below is an Eastwood Concours PRO HVLP Paint Gun 1.3mm needle/nozzle. The gun costs less than $200 and when I bought it, I also committed to cleaning it immediately after every use. I've done that and it works great!
     This gun it totally adequate to spray instrument lacquer and sealer. It comes with a smallish nozzle (1.3 mm) which is all that you need for lacquer.

     Using a clean, quality spray gun is the only way to even hope to get a quality finish.  Control is everything and cheap spray guns can be extremely frustrating when they clog, spit, spray erratically or just plain don't work at all.
     I recently visited a furniture refinishing professional to get some tips on buying a spray gun. His comment was that "None of them are worth a sh_t!“

    I have since learned that he is right... IF YOU DON'T CLEAN THE GUN RELIGIOUSLY. If you don't know how to clean a spray gun, it is very easy and takes less than 5 minutes.
     Give an acetone bath and cleaning to the nozzle, the cap, the needle, and the cup after each use.  There are many videos out there that explain how to clean a spray gun if one needs help. The trick, however, is to clean the gun with acetone immediately after use... everytime it is used. It takes only 3-4 minutes. More on this in Step 5.