Drop Bag for Testing Roofing Materials – DB400
While many of our bespoke enquiries focus on lifting bags, we occasionally take on more
specialised projects. This particular request was for a drop bag designed to test roofing
materials by simulating the impact of heavy debris.
The bag needed to be filled with glass beads up to 50kg and dropped from height onto roofing
samples. To achieve consistent and reliable results, the design had to be quite specific: a
rounded, ball-like base for even impact, combined with a narrower neck and durable webbing
straps for safe lifting.
As this was not a shape we had produced before, we began by developing a series of prototypes to explore the most effective way to construct the bag. While our standard bespoke lifting bags rarely require prototyping due to our experience, new designs are always carefully assessed to ensure the best possible outcome.
Our first prototype was based on our existing round-based bag designs. Joanna, one of our skilled sewing machinists, developed a method of shaping the base from a single piece of fabric, with the upper section made from four panels. Although this approach was workable, it didn’t quite achieve the desired shape and proved less efficient to sew.
We then refined the design. The second prototype, constructed from eight fabric panels, delivered a much more consistent and accurate rounded shape. It also simplified the manufacturing process and made it easier to incorporate key features, including reinforced webbing straps, a double-layered base for added durability, and D-rings for secure handling. The final result was a strong, practical design, with a form similar to a wrecking ball-style punch bag—well suited to its purpose.
Summary
This project highlights our ability to adapt to new and unique requirements. Through careful
prototyping and design refinement, we developed a durable and efficient solution that met the
client’s needs. The finished drop bag provides a reliable way to test roofing materials under
realistic impact conditions.
