Worldwide, there are hundreds of diver fatalities per year due to forgetting to check an air supply. In the vast majority of those fatalities, the “dive buddy” never knew that his partner was already dead. An innovative design for an extra air supply was made possible through 3D printing.
If diver safety is ever to be a priority, redundant air systems—which have been around for a long time—must become comfortable and easy to wear. Whether for sport and recreational diving, for search and rescue teams, or for certifying organizations to promote, redundant air systems must maintain the freedom and enjoyment of the diver in order to be most effective and useful, as well as to gain global industry acceptance. Redundancy is not a requirement of the business, even though hundreds of fatalities happen every year because divers forget to check their air supply during their dive. If redundancy isn’t a requirement, then it won’t be used unless it’s comfortable.
Most redundant air supplies are simply a second tank attached under one arm or to the side of their main tank. This affects a diver’s center of gravity, rolling them onto their side. The PonyPak eliminates this problem by placing the spare tank in front of the diver. With the PonyPak, the diver can gimbal without becoming off balance, and without the redundant supply getting in the way—it’s hardly noticeable.
The PonyPak is a harness system designed to transparently hold a second bottle of breathing gas for Scuba Divers. The internationally patented innovation is the attachment of the bottle, horizontally across the front torso of the diver, with an additionally patented four-point quick-release connector system. The solid harness system holds the tank securely without buckles or adjusters that can fail or come off adjustment. The harness requires no tools to assemble on the tank.
The harness—including the connectors, as well as the seals within the gas block—were produced by Midwest Composite Technologies of Hartland, WI. Each component was designed using SolidWorks 3D CAD software and uploaded to Midwest Composite Technologies to be analyzed, verified, and prepared for porting over to their in-house 3D printer machines. Since different materials were used for different parts of the harness, each component had to be ported to the correct machine after the drawings were saved in an STL format. All drawings and translations are double-checked for accuracy, then uploaded to the printer for production. Because of advancements in 3D printing technologies, prototype or production parts can be produced by some of the machines.
The harness system components were all dive appropriate coming right out of the 3d printers. According to William Messner, CEO and Chief Engineer for the PonyPak project, “The product has been in development for 6 years, and for the last five Midwest Composite Technologies has provided the components using their 3D printers for every iteration—printing several hundred parts, in total. With six years of design gestation and input from many industry professionals, the PonyPak is coming to market as a mature, time tested solution to a significant dive industry problem—avoiding fatalities with a second independent air supply.”
For full-face-masked divers, such as in public safety, the PonyPak gas block has a four-port gas block arrangement. Three gas sources enter the block horizontally, then exit vertically through the use of a selector knob and shaft assembly.
The 3d printed components included the main harness connectors, hose clips, bolts that hold the straps, and daughter brackets. Some of the components were made of plastic, while others were printed in stainless steel. As mentioned above, the seals within the gas block were also produced on a 3D printer. These seals (smaller than a dime in size) were printed using two different materials—a Viton-like material for sealing that is rated at 30 durometer was printed (overmolded) a hard ABS-like strength core. These seals have operated successfully under 200 psi internal pressures in 40 degree water. Overall, the harness has gone through and survived over 100+ test dives.
Benefits of the PonyPak
The PonyPak has a gas block, redundant system, and a second stage, which is the bail out for the main diver, a buddy diver, or for a victim (for search and rescue teams). The redundant PonyPak has a fourth port that allows another diver to patch in his main tank so that two full-face mask divers can buddy-breathe off the same tank without having to remove their masks. Plus, when a diver wears the PonyPak, the gas is delivered from under the full face mask instead of behind it. So, it’s easier to operate and less likely to be accidently caught on something and entangle the diver.
The patented, four-point quick release system retains the unit in any diver orientation (including upside down). And in an emergency, the PonyPak is instantly available to the diver or deployable to his buddy. The clips (plastic “D/G” Clip and SS “StrapSnap”) used to secure the PonyPak, are unique, patented parts with wide application in a multitude of non-related industries, and the general consumer.
Midwest Composite Technologies
www.midwestcomposite.com
PonyPak Inc.,
www.ponypak.com
