Are Separate Spray Guns Necessary?

The cost of a good spray gun is not negligible – at around $350 to $400 apiece, they cost as much as lower end personal or notebook computers – so the question naturally arises whether it is necessary to buy a spray gun for primers and another for paint and finishes.

Although many auto painting gurus recommend this arrangement, others argue that there is no logical reason for it in most cases, since the paint or primer will need to be cleaned completely out of the gun in any case, and remnants of paint would probably crosslink and ruin the device before you got around to using the next color.

There are some circumstances where separate spray guns for primer and paint might be appropriate, of course. At a large auto painting shop, some painters may be undercoating cars, while those in adjacent booths are painting or clear-coating others.

In this case, if the primer has specific characteristics and needs – for example, if the nozzle size varies between the primer and paint, or if compressor calibrations are preset for the different materials in different booths– then the process might be streamlined by using separate guns for each purpose. The whole “set-up” can be left in place, and the car taken to the appropriate gun for the layer of surfacing material that is about to be applied.

On the other hand, for smaller operations – including individual hobbyists or part-time car painters – keeping a separate spray gun for each material could prove to be a needless expense. You can only use a single gun at a time in this instance; the gun will need to be cleaned thoroughly after each use regardless, so that it will continue to function, so there is no chance of cross-contamination between materials; and since your projects are more infrequent, changing the nozzles and compressor settings is an occasional task that will not be much of a hardship.

If you need more flexibility for applying small areas of paint, or reaching inaccessible spots, then buying a touchup gun, or jamb gun as it is also called, is a good option for your workshop. This gun will be much cheaper than a second full-size spray gun and will add to the versatility of your painting in any case – a perfect combination for smaller painting operations.