Case study 5 - New Keel Pattern

Petticrows Ltd of Burnham-on-crouch - builders of the Team GB Olympic Gold medal winning Ynglings yachts use En-scan to create new keel pattern. When Petticrows Ltd needed a new casting pattern for the keel of their world famous Dragon racing yachts, in keeping with their innovative approach to a traditional sport they asked En-scan to give them precise data from one of their production yachts.

The iron keel casting for the Petticrows Dragon in encased in a fibreglass shell with a gap between iron and glass of 2 to 3 mm.

In order to get a perfect keel shape to fit inside the pre-prepared moulding, En-scan scanned the exterior of the fibreglass moulding picking up on the hull station marks in order to get a proper origin for the data.

Once the data had been captured, which took four hours, and converted to NURB patches En-scan manipulated it within SolidWorks to get the size of the casting pattern.  Using this data weight estimates for the cast keel were calculated and compared with expected values.

The data was also used to investigate the symmetry of the mouldings which reassured Petticrows that their vessels are indeed symmetrical.

A full-size foam model of the keel shape was CNC machined and offered into place to prove the shape. The result was a perfect fit.

Once the final keel shape has been approved, the data will be issued to Thurton Foundries in Norfolk to produce a CNC machined casting pattern ready for casting in iron.

www.petticrows.co.uk