How to spray nitrocellulose lacquer

Nitrocellulose lacquer is a fast drying solvent based spray on lacquer.

It is suitable for use over the following finishes:

Cellulose Sanding Sealer
Shellac Sanding Sealer
Tinted (Coloured but see-through) Nitrocellulose Lacquers
Solid Colour Cellulose Paints
Metallic Cellulose Paints

It may be possible to apply over other finishes, but this is not something we would officially advise. The solvents in nitrocellulose lacquer are strong, and have a tendency to melt and react with non-cellulose finishes. If spraying over a finish not listed above cannot be avoided then ensure that the first coats of nitrocellulose are very light sprays so that most of the solvents have evaporated before hitting the surface, thus minimising the chances of a reaction occurring.

Preparation

Wood

For a natural finish (a clear, see-through finish where the colour of the wood is not changed and the grain is still completely visible) the wood should first be filled and sealed.

Open pore woods such as Mahogany and its substitutes (Khaya Ivorensis, Sapele etc.) should be filled using a grain filler, such as our Thixotropic Grain FIller. Use a colour which most closely matches the colour of the wood itself. See our guides What is Grain Filler? and How To Apply Grain Filler.

All woods then require a Cellulose Sanding Sealer. See our guides What is Sanding Sealer? and How To Apply Sanding Sealer.

The sanding sealer coat should keyed in to 600 grit.

Shellac Sanding Sealer

Shellac sanding sealer should be applied as per the manufacturer's instructions and then keyed to 600 grit.

Tinted and Coloured Lacquer

Tinted lacquers are see through - they give colour, but the grain is still visible. The intensity of the colour depends on the thickness of the coat. Therefore, any keying in of tinted lacquers should be done with great care, and it is usually best to avoid entirely. Unless the keying is uniform across the whole surface then the sanding of keying in can lead to an uneven finish, something that is tricky to fix on a tinted lacquer.

Solid Colour Paint

Solid colour paints should be keyed to 600 grit.

Metallic Paint

Metallic paint should not be keyed before applying nitrocellulose lacquer, as any sanding can give an uneven looking colour and metallic effect.

Spraying Aerosols

Do not spray in cold or humid conditions. Cold and humidity can lead to moisture becoming trapped in the finish as it dries, giving a cloudy appearance. This is known as blooming. See our guide How To Fix Blooming.

IMPORTANT: Always work in a well ventilated area and wear suitable breathing and personal protection equipment.

Our Nitrocellulose Lacquer Aerosols are pre-mixed and ready to spray.

The lacquer can and workpiece should be at room temperature. If the lacquer has been stored in a cold shed or garage the can should be given a few hours to return to room temperature before spraying (approximately 22 degrees Celsius). It is not necessary to warm the can by soaking in hot water, etc.

Shake the can for two minutes immediately prior to use.

Aerosol cans are activated by depressing the nozzle on top of the can. The nozzle should be depressed fully - only partially depressing the nozzle can lead to a weak or spluttery spray. Coat thickness can be controlled by speed of movement over and distance from the workpiece.

Move across the workpiece at a consistent speed, changing direction off the edge so that the lacquer does not pool around the edges. Overlap each pass by 50%. Work with the workpiece laying flat, not hanging up, to reduce the risk of drips forming.

Depending on the surface onto which you are spraying 2-5 coats will usually be sufficient. Spray coats 4 hours apart. Key lightly before spraying new coat. Do not spray more than three coats in one day.

Spray Gun

Do not spray in cold or humid conditions. Cold and humidity can lead to moisture becoming trapped in the finish as it dries, giving a cloudy appearance. This is known as blooming. See our guide How To Fix Blooming.

IMPORTANT: Always work in a well ventilated area and wear suitable breathing and personal protection equipment.

Our neat bottled lacquer should be thinned 10-30% before spraying using anti-bloom thinners. If the lacquer has been stored in a cold shed or garage it should be given a few hours inside to return to room temperature (approximately 22 degrees Celsius).

Move across the workpiece at a consistent speed, changing direction off the edge so that the lacquer does not pool around the edges. Overlap each pass by 50%. Work with the workpiece laying flat, not hanging up, to reduce the risk of drips forming.

Depending on your thinning ratio and the surface onto which you are spraying 2-5 coats will usually be sufficient. Spray coats 4 hours apart. Key lightly before spraying new coat. Do not spray more than three coats in one day.

Finishing

See our guides on How Long Should Nitrocellulose Lacquer Be Left To Dry Before Polishing and How To Polish Lacquers and Paints.