Whether you have a new or aging paint booth, the steps you take throughout the painting process — from prep work to the final finish — can significantly impact how well your booth performs. If a spray booth is not properly used and maintained, a paint booth often ends up creating a bottleneck in a paint shop. By following the proper paint booth procedures, you can not only improve the quality of your paint finishes, but also increase the overall productivity of your spray booth, boosting your business’ bottom line.
Prep for Success
Proper paint booth operation begins before you even enter the spray booth. The preparation you put into each job plays a critical role in achieving the highest quality results. Consider the following factors prior to painting a vehicle or part:
If your part or vehicle is coming from storage, pay attention to potential temperature differences between the storage area and the spray booth. Temperature differences between the product surface and the coating can cause problems with adhesion or gloss and other defects.
Cleaning the Vehicle or Part
Before painting, make sure the vehicle’s surface has been properly cleaned of any chemical contaminants it may have been exposed to. In a prep booth, use compressed air to clean loose contaminants. Follow this with a lint-free wipe or tack cloth. For best results, wipe in a unidirectional method from one side or end to the other.
Always handle parts with lint-free gloves during and after prep work. Naturally created oils and particulates from human skin can contaminate part surfaces and create blemishes in the finish.
Bringing Vehicles or Parts into the Booth
Before you open the doors to your paint booth, make sure it is operating in spray mode; this ensures that any airborne contaminants will be drawn to the exhaust filters. Also, if you have a drive-thru paint booth, keep the opposite doors closed as the vehicle enters and exits the booth.
Improve Your Spray Zone
Once you are in the paint booth, maintaining an efficient spray zone is key to achieving the best results. The following steps will help you to maximize the spray zone in your paint booth:
1. Position the Vehicle Properly
In a downdraft booth, center the vehicle over the grating to promote proper airflow. In crossdraft, side downdraft or semi-downdraft booths, place the vehicle in the center of the booth so that you have plenty of room to move around. All items to be painted should be placed within the surrounding spray zone.
When masking in a downdraft spray booth, make sure you are not blocking the grated areas. Extend masking paper or plastic at most 6 inches below the vehicle and mask wheel wells and wheel covers only if they are within the area being sprayed. The remaining wheel wells should be open to create a consistent air path.
3. Balance the Air Pressure
To keep contamination off the vehicle, you should make sure the air pressure in your paint booth is correctly balanced. A slightly positive pressure will ensure the cleanest paint job. That pressure causes a layer of slow-moving air — known as boundary air — to form on the vehicle surface. Boundary air shields contaminants from painted surfaces.
If the booth has too much positive pressure, more air is being introduced to the spray booth cabin than can be removed. This causes contamination from the booth’s walls and floors to enter the spraying zone.
Negative pressure, on the other hand, reduces the shield of clean air that is created and draws in contamination from door leaks or booth openings. If you need to make any pressure adjustments, do so when the vehicle is in the spray booth cabin and all the doors are closed.
4. Control Paint Booth Temperature While Spraying
In addition to air pressure, spray booth temperature is also important. Your spray temperature should remain constant, ideally between 72 and 75 degrees Fahrenheit. As temperatures increase, airflow slows down. Paying attention to each of these factors will help you produce the best possible paint finish.
5. Refer to Paint Data Sheet Before Spraying Base & Clear Coats
When it is time to paint, apply your base and clear coats according to the paint manufacturer’s recommendations. This ensures the best paint finish results.
Keep Contamination Out of the Booth
After the necessary coats have been applied, allow the paint booth to flash at least three minutes before changing over to the cure cycle. This allows overspray in the air to be removed, providing a clean atmosphere for curing.
After the cure cycle, wait at least five minutes for the booth to cool down before removing the vehicle. Do not shut off the paint booth between paint jobs; any contamination in the booth will become airborne and land in the paint.
Maintain Optimal Booth Performance
A contaminated paint job is often the result of a dirty or poorly maintained booth. A few simple booth maintenance steps will help create a safe and efficient working environment for higher quality paint jobs. They will also extend the life of your paint booth. Follow these recommendations to ensure your spray booth is well maintained:
Regularly Change Booth Filters
Spray booth cleanliness begins and ends with your intake and exhaust filters. Changing these filters on a regular schedule will ensure safe and effective airflow. Your paint booth or filter supplier can work with you to design an effective schedule to maintain your spray booth’s performance while keeping cost efficiency in mind.
Keep Dust Out of the Booth
It is important to keep dust out of your spray booth. When not in use, keep the paint booth doors closed. When you need to open the booth doors to bring an object in, make sure the booth is on and running. Other tips include not leaving unnecessary items in the booth, limiting traffic in and out of the booth, never sanding in the booth and never spraying without a lint-free painter’s suit and head cover. Painting attire should be stored in a clean area.
The painting process often leads to overspray that needs to be carefully cleaned. Overspray can end up on booth walls and floors, as well as paint guns and air hoses. If you do not take proper care of it, paint can become airborne or flake off onto painted surfaces. Whatever method you choose for cleaning, make sure it is approved for use in hazardous locations like your booth. Peelable booth coatings such as Booth Shield or booth protection paper are great options for protecting your investment. You can find more tips for cleaning your paint booth in the Paint Booth Cleaning Checklist post.
Ultimately, proper booth operation and maintenance are key to achieving the best finish possible for each vehicle while also increasing shop throughput and booth longevity. It begins before the vehicle even enters the booth and does not end when the spray gun is put down. Emphasizing proper prep work, optimizing your spray zone in the booth and focusing on booth cleanliness and maintenance build good habits that elevate the quality of the work coming from your shop now and into the future.