Surfski rudder plug for moulding/casting from.

thingiverse

The aluminum rudder measures 240mm deep and holds a volume of 165mm. It is slimmer than the carbon fibre think rudders commonly used in design. Given its density, approximately 2.7 times that of water, an aluminium rudder with these dimensions will weigh around 280 grams when submerged. To shield its surface from damage you can give it a wire brush, have it anodized and dye... just look up the necessary procedures. This rudder features a tapered shaft entry point, narrowing down from 8mm to 4mm in diameter over a distance of 60mm. It also includes an indentation for installing a grub screw but cutting some gripping notches into the stainless steel rudder shaft and casting the aluminium around it would be even better. Research sand casting techniques and gather silica sand and bentonite clay. Then construct a moulding box with interior dimensions that exceed those of the fin itself. Alternatively, you can make a mold around the rudder section and subsequently cast carbon fibre using low viscosity epoxy resin. Opt for infusion moulding resins for the best results in wetting out characteristics. Scaling up the rudder within your slicing program may allow its use as a plane part for tail, wing or rudder sections. In such capacity it would create neutral lift which is particularly advantageous when flying acrobatic planes that require stable performance from all sides of their axis. **Printing Instructions** This print yields the best results with my printer set to Cura parameters: nozzle diameter - 1mm; print speed - 30mm/s; infill percentage - 20%. Opting for finer layer thickness can reduce future sanding efforts needed during post-print processing.