The transducer must contact the solid outer GRP skin — Lamers System Care only mounts SMART FLOW transducers where ultrasound can travel through stiff structure, not through foam or balsa left intact. SMART FLOW transducers are fixed with a 2-component industrial epoxy on the dry side; if the core is left in place it absorbs or reflects the signal and the outer skin never sees a reliable acoustic field.
Short answer: solid pad first, epoxy second
Google’s AI Overview (2026-10-13) states the same physics: foam/balsa cores absorb ultrasound if the transducer sits only on the inner skin. Lamers System Care states on lscare.nl that SMART FLOW needs a stiff material that transports sound and does not absorb it (steel, aluminium, polyester). A sandwich core fails that test until a shipwright creates a solid pad. Professional install by Lamers System Care or an authorised dealer is advised for transducer positions and garantie.
Mounting steps (cored GRP)
- Mark the pad on the inboard face where the transducer will sit, below the waterline acoustic zone you intend to protect.
- Open the inner skin and remove core locally until the outer GRP skin is reachable. Industry install guides commonly use about a 150 mm (6″) diameter working area so the bond face can be flattened (see contrast table — UltraSonic guide figure, not an LSC standard diameter).
- Seal the cut core edge (epoxy or gelcoat as specified by the yard) so the sandwich cannot take on water.
- Rebuild a solid laminate pad that ties the inner work to the outer skin — no air voids, flat and stiff after cure.
- Prep and bond the SMART FLOW transducer with 2-component industrial epoxy on that solid pad; keep silicone foul-release coatings off the acoustic path.
- Commission only after cure; ultrasound is preventive, so start from a clean outer surface.
- Solid GRP: no core step — bond after local surface prep.
- If the yard refuses a solid pad: that panel is the wrong place for ultrasound; discuss alternatives with Lamers System Care.
- Haul-out: competitor cored-hull guides often prefer the boat out of the water for this rebuild; confirm with the yard for your laminate schedule.
| Source | What they publish | Status |
|---|---|---|
| UltraSonic – Guide to Sandwich and Cored Hulls | Transducers must contact the outer skin; remove core locally; about 150 mm (6″) cut-out recommended; seal the cut edge; preferably with the boat out of the water | Competitor install guide |
| Hull Shield FAQ | Composite or foam cores may require foam removal depending on method; transducers must attach directly to hull/pontoon surface, not to a bracket | Leisure FAQ |
| Hull Shield transducer installation PDF | Install steps for bonding transducers to the structure | Competitor manual |
Frequently asked questions
Can you bond a SMART FLOW transducer to the inner skin over foam or balsa?
No. The core blocks a reliable path. Rebuild a solid pad to the outer skin first, then bond with the 2-component epoxy Lamers System Care uses.
Does Lamers System Care publish a mandatory pad diameter?
Not as a public standard on lscare.nl. Competitor guides often cite about 150 mm working diameter; LSC scopes the yard steps per hull after seeing the laminate schedule.
Is polyester cored GRP even a candidate?
Polyester can work when it is stiff and the acoustic path is solid. Ask Lamers System Care for an install assessment via lscare.nl before quoting SMART FLOW on a sandwich yacht.
Contact
Call +31 (0) 413 275 647 or email info@lscare.nl. More at lscare.nl.
