Spraying Nitrocellulose Lacquer
NITROCELLULOSE FINISH HISTORY
Nitrocellulose was the first documented man made "plastic", and was created in 1862. It was composed of cellulose treated with nitric acid and a solvent.
Celluloid was developed in 1869 by John Wesley Hyatt when he created a material called camphor nitrocellulose, the first "thermoplastic". His invention was a contest entry to find a new material to make billiard balls that were originally made out of ivory.
In the early 1920’s nitrocellulose lacquer became the preferred finish on high-quality furniture and musical instruments. It is an exceptionally fast-drying solvent that provided a durable finish was was easy to work with. Hence being still used today. And making it over 100 years old in the instrument business.
It is a myth that nitro "needs" months to cure before sanding and polishing. It's a thermoplastic finish. Meaning it softens as it's polished due to the heat caused by friction and hardens as it cools when finished. Anyone who says this should learn their chemistry. (Thermo(heat) plastic(moldable). *Greek
Big builders like Gibson and Fender spray the same nitrocellulose lacquers you can buy here. They aren't chemically altered, catalyzed or changed to cure faster. They sand and polish well before the "1-2 month secret" myth cure time.
It is also a myth that nitrocellulose lacquer is or was illegal in Canada. We've sprayed our colours for years and years perfecting them with our private instrument/lacquer business. You never saw the stuff available for purchase for basically one reason. There was a contract between a large supply company in Canada and the manufacturer that spanned some 30 years for distribution rights. Unless you mixed your own colours like us you were SOL.That contract is now over. This may be why you see other companies offering it as well as other "nitro type products" that are similar to our colours/the originals.
Nitrocellulose is historically a very forgiving finish. Many mistakes have been made and fixed within 1 coat. Spatter, runs, orange peel. It is all repairable. Nitrocellulose is a highly sought after finish for a reason. It is all top manufacturers most expensive/ top of the line finishes. It has been used in the finishing of musical instruments for over 100 years. It provides a durable finish while aging with the player. It is light and thin and lets the instrument resonate and vibrate more freely than any other protective finish. Poly finishes do not. Poly finishes are very thick, weigh a ton, and when they do chip or crack it looks terrible. Oil finishes are nice, but a custom colour oil finish? No way. Nitrocellulose only has one real downside. It isn't good for your health. So people, please be smart about it. Don't spray indoors (your house...ever). Use a well ventilated area (ex. garage, spray booth, shed, or outside). Always wear a respirator and safety glasses. If you have any questions at all, please feel free to email the shop. Or read the back of the product, look up the SDS or product information sheets. We will answer all of your questions to the best of our ability.
Spraying Nitrocellulose Lacquer
Spraying Nitrocellulose lacquer has a few rules (guidelines). That being said, many manufacturers have their own way of using/changing these rules and it all works. A couple of quick "guidelines",
1) Make sure your work area is always clean and dry
2) Spray when conditions permit. Humidity being the most important factor. Try not to spray much over 60% humidity to be safe. An increase in humidity can cause blushing.
3) Spray warm lacquer. Never cold. Cold lacquer will spatter. Large builders use heated lacquer, but you can use hot tap water. Warm your can a few minutes before spraying for best flow. This step makes sure the lacquer flows out like it is supposed to. (Very Important)
4) Spray enough lacquer, but not too much. Too little can result in orange peel or an "over spray" effect (a rough surface caused by lacquer drying before it hits your guitar). Too much can produce a run or sag.
5) Spray approx 8-12 inches away from your guitar or neck. Overlap as much as possible usually 50% is enough. To close can produce runs and to far away can create and effect when the lacquer dries before it hits the guitar body.
Our lacquers and toners are mixed to the perfect spraying consistency allowing you to have all of the control over your finish. Unlike other lacquers which are thinned down considerably. These lacquers tend to run easily, and blush more due to their over thinned properties.
6) If you have a run or sag, STOP! Let dry and sand out with 400 grit. Remember it is fixable. Just let it dry. This is key. It doesn't have to be 24 hours, 1 hour should be fine.
7) Do not sand metallic. The small metal particles suspended in the colour coat is what makes a metallic a metallic. The particles are meant to be suspended. Sanding will ruin this effect and more colour will need to be applied.
8) Let dry an absolute minimum 3 days after spraying your final coat. It needs time to cure. A week is better, and it will harden more each week it cures. Gibson and Fender don't let their guitars sit for a month before sanding and polishing. Draw your own conclusion, but a week or two is recommended for first time finishers.
*It is a myth that nitro needs months to cure before polishing. It's a thermoplastic finish. Meaning it softens as it's polished due to the heat caused by friction. Anyone who says this should learn their chemistry. (Thermo(heat) plastic(moldable). *Greek mythology.
9) Wet sanding and polishing is time consuming. Take your time. Sand in one direction. I have found it produces less obtrusive scratches than a circular direction. Use a block to help stay flat and always use a lubricant (water, naptha, etc.)
10) Have fun. Enjoy learning what makes these guitars so special. If you have questions, ask.
Aerosols are easy to use with less equipment and they store when not needed. There is enough product in our cans for up to 3 coats of lacquer on a normal guitar body. Usually the first coat is lighter, followed by wetter coats. As far as coverage goes. you only need good coverage on the primer and colour coats. The sealer will build a flat level surface and the clear is what needs to be built up due to wet sanding. Hence needing more cans of clear lacquer.(Always clear nozzle after spraying) you can also put it into thinner. Our colours are supplied with a cone tip and a fan tip. Use the cone for more precise application in the cut aways and sides of the body. Switch to the fan tip (larger) for a wider pattern for the front and back of guitar body. Clean your tips with lacquer thinner if needed. Our larger sized fan tips are interchangeable with all of our spray cans. These tips are interchangeable and can be used on any can. Always keep thinner handy. Drop your tips into the tin of thinner for best results.
Spraying with Spray Guns
If you have the equipment and know how to use it this method is great. Our colours come in a variety of containers. These provide enough lacquer for any project you have. Clears and sealers are also available in a variety of containers.These both should leave you with enough product to get good coverage while not wasting lacquer or having a bunch left over. If you know how to use your equipment you should not run into issues. If you are spraying with a ton of over spray and wasting good quality lacquer you may need more product. Make sure your gun is set right before spraying the lacquer. Guitar bodies and necks are smaller than most projects. You don't need the same settings as you would for a car to get good coverage.
If your nozzle appears clogged, stop. Remove tip and place into lacquer thinner. This will remove the clog and you can continue. This can happen if your lacquer is cold. That is why you should use warm lacquer. Should you run into any other issues please feel free to contact the shop for help.
Wet Sanding and Polishing
When you feel your finish has hardened you may start your wet sanding and polishing. There is no "one way" to do this. When you start wet sanding you can start anywhere from 800 to 1500 grit depending on your finishing experience. This is because wet sanding and polishing overlap based on products. Polish is just a "liquid" sandpaper so to speak. The more coarse the polish is the more it will "remove" scratches still leaving behind smaller ones. Nitrocellulose is a "thermo-plastic" finish. This means it "softens" as it heats up (polished/rubbed). No matter how hard your finish is, 1 or 4 weeks cured. It will still need to be softened when polished. This is how Gibson and Fender can wet sand and polish after only 6 to 8 days of curing. If this is your first time finishing we would recommend letting your finish cure one week minimum to two weeks. Sand up through the grits starting at 1000 moving to at least 2000 grit "p" grade wet sandpaper. Then polish with a medium fine compound followed by a fine compound/swirl remover. Let your finish cool after buffing a few minutes. (because it's thermo-plastic) It's still soft due to the heat caused by buffing. After it's cooled, clean off the leftover compound with a soft cloth or clean buffing pad and move to the next step until you are finished and have a mirror shine. If you are doing a relic job you can stop at any point you feel your guitar looks the way you like it.