PVC Transom Board Base, Grey – 25 mm Stern Support for Inflatable Boat

A transom board base is a specialized PVC component designed to firmly attach the wooden motor-mount board (transom) to an inflatable boat’s tubes. In inflatable boats, the transom board is held in place by two of these PVC supports (one on each side of the board), creating a stable bond between the flexible inflatable hull and the rigid structure that carries the engine. Code 66.080.20 refers to a bracket sized for a 25 mm thick transom board, in light grey color (RAL 7035) to match the standard color of most inflatables.

Dimensions and design: The base features a large rectangular pad – 540 x 100 mm – which is glued to the boat’s tube. This broad footprint is crucial for load distribution: when the engine pushes or vibrates, the forces are transferred through the transom into the bases and spread over a wide area of the tube, rather than concentrating in one spot. The clamp “socket” thickness – 25 mm – corresponds to the typical thickness of wooden transom boards (very small outboards sometimes use 18–20 mm, but 25 mm is common for strength). The “pocket” height of the bracket is about 47 mm, meaning it grips the transom board 47 mm up its side for stability.

Material and durability: The entire part is made from molded PVC – the same type of material as the inflatable boat fabric, but in a thicker, more rigid formulation for structural elements. Critical points may be internally reinforced or thickened for extra strength. The PVC is formulated to be UV-resistant and marine-grade – it won’t crack or embrittle under sun exposure, nor delaminate due to saltwater. This is important because transom bases endure constant stress: from the engine’s weight and thrust, from pounding through waves, and from the mounting/dismounting of the motor.

Installation: To install the base, typically the boat is inflated and the transom board positioned between the tubes. After carefully marking the placement, the base is glued onto the tube with a proper 2-part PVC adhesive. The large 540x100 pad ensures a strong bonding area – it’s important to apply the glue evenly across the entire surface. Often additional strips or patches are glued over the edges to smoothly taper and reinforce the attachment. Once glued, the wooden board slides into the “pockets” of the two mounted bases. Usually, these bases have pre-formed holes for bolts or pins that secure the transom board to them (preventing it from lifting out). For example, this model might have two small stainless locking bolts to clamp the board from the outside. After proper installation, the transom board becomes an integral part of the boat – as solid as if it were factory-installed.

Applications:

• Replacing an old transom mount: If your boat’s transom supports are peeling off or cracked, this product is the perfect spare part. The size is universal for many inflatable boats with small to mid-sized outboards (typically up to ~15–30 HP, where the transom board is ~25 mm thick).
• New boat builds or kits: For those assembling a boat from a kit or doing custom modifications, these bases provide a ready-made solution for attaching a transom to the tubes.
• Upgrading for a bigger engine: If you’re moving up to a more powerful engine, you might want to reinforce the transom attachment. Installing new, fresh supports (in place of old ones softened by years of use) will provide extra security.
• Note: Usually one transom uses two pieces – this product is sold individually, so you’d purchase two (left and right) for a full set. Some customers also buy an extra as a spare to have on hand for future repairs.

As the critical link between your outboard motor and inflatable boat, properly installed PVC transom bases give you confidence in your engine mount. They eliminate wobble or looseness in the transom, keeping your boat structurally sound even under power. With this product, your transom assembly will be restored to factory standards, and your inflatable will carry its engine securely and steadily.