 |
For decades, the welded A-Frame has been the "pickup truck" of the glass industry—reliable, simple, but blunt. While excellent for bulk storage of identical sheets, it fails miserably in today's high-speed, custom fabrication environment. |
The fundamental flaw of using A-frames for Work-In-Process (WIP) is accessibility. A-frames are designed for bulk packs where every sheet is the same. But in custom window production, every sheet is different.
If your production schedule changes and you need a specific lite buried in the middle of an A-frame stack, your line stops. Operators waste valuable minutes shuffling glass. With a random access harp rack, every single slot is independent. You can pick any sheet, in any order, at any time. This flexibility allows your sorting team to adapt instantly to rush orders or re-makes without disrupting the entire batch.
A hidden cost of A-frames is freight. Because they are typically large, welded triangles, they consume massive amounts of container volume while being mostly empty space. You are effectively paying to ship air.
Our Harp Racks feature a smart Knock-Down Design. We can disassemble the uprights and base into a flat-pack format. This allows us to fit 400% more units into a shipping container compared to pre-welded A-frames. For international buyers, this logistics savings alone often pays for the upgrade.
Smart engineering: Disassembled shipping drastically reduces ocean freight costs per unit.
On an A-frame, glass leans against glass. The weight of the stack creates pressure, and any vibration during transport causes friction between the sheets. For standard clear glass, this might be acceptable. For soft-coat Low-E or high-performance architectural glass, it's a disaster waiting to happen.
Harp racks use an isolation strategy. Each lite sits in its own private slot, guided by PVC/Nylon tubes. There is zero glass-to-glass contact. The weight is carried by the base, not by the glass surface. This design eliminates the "rub marks" and coating scratches that frequently occur on A-frames.
Individual PVC-lined slots ensure zero contact between sensitive coated glass surfaces.
The initial unit cost of a harp rack is typically higher due to the complexity of the materials (many individual rollers and dividers). However, when you factor in the reduction in shipping costs, space savings, and reduced glass breakage, the ROI is often achieved within the first year.
Not necessarily. A-frames are still excellent for long-term storage of raw glass packs (uncut sheets). Harp racks are best deployed in the "active" zones of your factory: sorting after cutting, pre-tempering, and IGU assembly buffering.
No. We design them for intuitive assembly using standard tools. Two workers can typically assemble a complete harp rack in under 30 minutes. We provide detailed visual guides to ensure correct torque and fit.
Standard A-frames cannot handle curved glass safely. While standard harp racks are for flat glass, the "slot" concept can be customized with wider spacing to accommodate bent or curved glass much more securely than a flat leaning rack.
This depends on the model and glass thickness, but a standard unit typically holds 50 slots. Compared to a similar-sized mobile A-frame which might safely hold 20-30 loose sheets, the density is significantly higher.
