Adjusting Cracking Pressure: Aromic Ss1 Tips And Tricks

Cracking pressure is the minimum upstream pressure required to open a check valve enough to allow detectable flow. In scuba diving, cracking pressure is the pressure it takes to get the regulator to start delivering air to you. The adjustment knob on the second stage of the Atomic ST1 can be used to control the pressure needed to crack the reg. This knob is known as the AFC (anti-flow control) knob and can be turned clockwise or anti-clockwise to adjust the pressure.

Understand what cracking pressure is

Cracking pressure is a critical specification for check valves, which are widely used in applications involving the flow of liquids or gases. It refers to the minimum upstream pressure required to open a check valve enough for a detectable flow of liquid or gas to pass through. In other words, it is the pressure at which the first sign of flow is observed.

Cracking pressure is typically measured in pounds per square inch (psi), pounds per square inch gauge (psig), bar, or kPa (their metric equivalents). It is important to understand cracking pressure when choosing a check valve for a specific application. Selecting a check valve with the correct cracking pressure ensures consistent flow and prevents premature wear.

The cracking pressure of a check valve depends on its design and can be influenced by factors such as the condition of the valve, orientation, and contamination in the fluid passing through it.

In the context of the Atomic SS1, which is a regulator used in scuba diving, cracking pressure refers to the pressure required to activate the regulator and allow air to flow. Adjusting the cracking pressure on the SS1 involves using the AFC (anti-flow control) knob, which controls the pressure needed to "crack" the regulator and start the flow of air.

Learn how to test it

Testing the cracking pressure of a second-stage scuba regulator is a straightforward process that can be done using a Magnehelic meter and a test bench. Here's a step-by-step guide on how to test the cracking pressure:

• Calibrate the Magnehelic meter: Start by locating the small screw at the bottom of the meter and gently turn it left or right until the red pointer is in the "0" position.
• Connect the meter to the test bench: Push the black plastic stint on the red rubber hose into the test bench adapter.
• Remove the original mouthpiece from your regulator.
• Connect the regulator to the meter: Slide the black rubber part of the hose over the mouthpiece of the second-stage regulator.
• Breathing during the test: Use the white part with the hole in the middle of the test bench adapter to breathe in and out during the test.
• Measuring the cracking pressure: Inhale as slowly as possible and watch the Magnehelic meter. The moment when a light airflow is created is the "cracking pressure." Write down the number indicated by the meter.
• Compare to the service manual: Refer to the service manual of your regulator to find the ideal cracking pressure. If the value you measured deviates significantly, you may need to adjust your regulator or check for broken or leaking parts.
• Optional: Connect an intermediate pressure gauge: For a more comprehensive test, you can also connect your inflator hose to the test bench or use a digital Magnehelic meter with a separate intermediate pressure gauge. Repeat the breathing test while also watching the intermediate pressure gauge. The Magnehelic meter will show the cracking pressure when the first airflow occurs and the pressure in the intermediate pressure gauge drops.

It's important to note that cracking pressure is a critical aspect of scuba regulators, and making adjustments should be done carefully. Always refer to the manufacturer's service manual for specific instructions and guidelines.

Know the ideal cracking pressure for your regulator

Knowing the ideal cracking pressure for your regulator is essential for a seamless diving experience. Cracking pressure refers to the amount of inhalation effort required to open the valve of a second-stage regulator and start the airflow. This is a critical factor in determining how easy or challenging it is to breathe from your regulator while underwater.

The ideal cracking pressure for your regulator can vary depending on several factors, including the specific model of your regulator and your personal preferences. Each brand's second-stage regulator will have an ideal cracking pressure stated in its service manual. This value is determined by the manufacturer and serves as a guideline for divers to adjust their regulators accordingly.

To find the ideal cracking pressure for your regulator, you can refer to its service manual. Look for the section that specifies the cracking pressure or inhalation effort required. This value is typically given in "inches of water" as a measurement unit. However, if your service manual provides measurements in "mbar" or "millimeters of water," you can use online calculators to convert these values into "inches of water" for comparison.

It's important to note that the ideal cracking pressure may differ between your primary and secondary (octopus) regulators. Generally, an octopus regulator is set to a slightly higher cracking pressure to reduce the likelihood of free-flowing air when it's not in use. Additionally, some regulators feature an adjustment knob or dial that allows you to fine-tune the cracking pressure according to your comfort level and diving conditions.

Remember, the ideal cracking pressure is crucial for a comfortable and controlled breathing experience during your dive. By consulting the service manual and making adjustments as needed, you can ensure that your regulator performs optimally and provides you with the necessary airflow while underwater.

Understand the role of the adjustment knob

The role of the adjustment knob on the Atomic SS1 is critical to its functionality and performance. This knob, known as the AFC (Anti-Flow Control) knob, is specifically designed to control the cracking pressure of the regulator. Unlike typical regulators, the Atomic SS1 is unique in that it does not freeflow, even when the knob is turned to the extreme counterclockwise position. This is by design and does not indicate the need for any adjustments.

The purpose of the AFC knob is to allow divers to control the pressure required to "crack" or activate the regulator. By adjusting this knob, divers can fine-tune the sensitivity of the regulator to prevent unwanted freeflow. For example, when diving against a current, increasing the pressure via the AFC knob can prevent the regulator from freeflowing due to increased pressure on the face of the second stage.

The AFC feature on the Atomic SS1 is a significant advantage, especially when compared to other regulators in the market. This feature ensures that the regulator's cracking pressure and inhalation resistance are optimally set, providing a seamless and controlled breathing experience for divers.

It is worth noting that while some divers prefer their regulators to freeflow, this is not a standard setting for the Atomic SS1 or other similar models. Any adjustments to enable freeflow should be done by a trained professional who understands the intricacies of regulator adjustments.

Learn how to adjust the knob safely

Learning how to adjust the knob safely on an Atomic SS1 is a straightforward process. Here is a step-by-step guide:

Understanding the Knob:

The knob in question is the AFC (Anti-Flow Control) knob, which controls the pressure required to "crack" the reg. It is not meant to make breathing easier or harder but to prevent free flow when diving into a current.

Adjusting the Knob:

• Initial Position: The AFC knob is typically kept fully counter-clockwise, ensuring the reg does not free flow.
• Adjusting in Currents: If you encounter a current and the reg starts to free flow due to increased pressure, turn the knob clockwise in half-turn increments. This will prevent the free flow.
• Fine-Tuning: Depending on your specific needs and preferences, you can fine-tune the knob settings. For example, if you want to reduce the sensitivity to head-on currents, you can force the AFC lever into the flow by turning the knob clockwise.

Additional Tips:

• Dive Conditions: Keep in mind that the knob settings may need adjustments depending on your diving conditions. For instance, if you're swimming into a current, you may need to turn the knob clockwise to prevent free flow.
• Maintenance: Regularly inspect and maintain your SS1 reg to ensure optimal performance and safety. Refer to the SS1 manual or seek advice from experienced divers or professionals for maintenance tips.
• Safety First: Always prioritize safety when adjusting the knob. Ensure you understand the purpose and impact of each adjustment, especially when diving in challenging conditions.
• Seek Expert Advice: If you're unsure about adjusting the knob or encounter any issues, don't hesitate to seek advice from experienced divers or professionals. They can provide personalized guidance based on your specific setup and diving conditions.

Frequently asked questions