How to match a spray gun to a compressor?

[darklightBoy]

Hi all,

Looking to find my way in the spray painting world for DIY, but I'm getting a bit confused about matching a compressor to a spray gun. In this thread here the advice given is that the free air delivery of the compressor should exceed that of the spray gun. Yet the Ozito 3 Piece Gravity Feed Air Spray Gun Kit page states "an air compressor with a minimum delivery rate of 85 litres per minute is needed to run this spray gun" even though the air consumption in the instructions states 141-283 litres per minute.

Is the product page wrong? In the same vein, the Ryobi Airwave spray gun gives a figure of 210 litres per minute, yet Ryobi's own Airwave compressor has a FAD of 120 litres per minute, or maximum of 190.

Insight appreciated.

[EricL · Accepted solution]

Hello @darklightBoy, 

Welcome to the Bunnings Workshop community. It's sensational to have you join us and thanks for sharing your question about spray guns.

Matching a spray gun to a compressor can definitely feel a bit tricky, especially when product specs seem to send mixed messages. Let me break this down for you, using current Bunnings products like the Ozito and Ryobi tools you mentioned.

The key to pairing these tools is understanding two critical figures: the spray gun’s air consumption rate (measured in litres per minute or LPM) and the compressor’s free air delivery (FAD). FAD is the actual air the compressor can supply, and it’s often less than its maximum or "theoretical" output due to efficiency losses.

For the Ozito 3-Piece Gravity Feed Air Spray Gun Kit, the product page says it requires a compressor with a minimum delivery rate of 85 LPM. This is likely a base figure to keep the gun functional for light or intermittent use. However, the instructions give a more realistic air consumption range of 141-283 LPM depending on the nozzle and task. This means that for continuous spraying, you’d ideally need a compressor with an FAD closer to the higher end of that range—certainly much more than 85 LPM.

Now, take the Ryobi Airwave Spray Gun, which has an air consumption rate of 210 LPM. Ryobi’s Airwave compressor has a max output of 190 LPM but only an FAD of 120 LPM. This mismatch means the compressor will struggle to keep up with the spray gun during prolonged use. It might work for short bursts, but you'll likely experience pressure drops that impact your spray quality.

So, why the confusion? Manufacturers often list minimum compressor requirements that can technically power the tool, but they don’t always specify whether the compressor can handle sustained usage. If you’re planning to spray continuously (eg. painting walls or large surfaces) the FAD of the compressor should exceed the gun's air consumption rate. This ensures smooth performance without pressure dips.

For tools like the ones you’re considering, you’d need a more powerful compressor—likely one with an FAD of at least 150-200 LPM or more. I'm sorry but the store doesn’t currently stock compressors at that performance level.

If you’re just starting out, consider the Ozito Portable Electric Spray Gun instead of air-powered models. These plug-in guns don’t require a compressor and are excellent for most DIY tasks like furniture, walls, or even fences. They simplify the setup and work well for beginners while avoiding the compressor-spray gun compatibility headache entirely.

Spray painting can be super satisfying, so don’t let the numbers overwhelm you. If you want more advice, chat with the friendly team at the store they'll be more than happy to provide further information.

If you need further assistance, please let us know.

Eric