Saturday, 13 February 2016

CNC Machining a 1/10th Scale Sailboard

Here is a quick video of a 1/10 scale model I machined of the HD Slalom 83.  The objective was to view both the hull and deck concaves and to check all of the other contours looked ok before I sent the template files off for laser cutting.  The plan is to cut the full sized board when I have finished my large scale CNC router.

Normally the hull would be machined before the deck since it is more critical for performance than the deck.  Also you can vac dag the hull before machining the deck for added dimensional stability, and machine trim the hull sandwich and rail tuck below the wide point of the rail.

In the video the deck was machined first as it was easier in this case, but, unfortunately I squeezed the polyester bog supports out wider than the tape on the foam and a few small strips of the deck got eaten.

Hopefully I can post about modelling the board in SolidWorks and what works for me.

Sunday, 7 February 2016

HD Customs - Slalom 83 (150L)

I have finally finished my latest build - the Slalom 83 (formally Creeper 83, I am reserving creeper for the speed boards ;)

The final specs are:
Width: 83cm
Length: 247cm
Volume: 150L
Weight: 8.5Kg

I went in a new direction with this design and incorporated a double vee flowing into a tri-panel vee in the tail.  The intention is that it will plane early but not become flighty at speed or with smaller sails.  I tried the board out yesterday at the top of its range and couldn't find fault. The shoulders never caught in the chop or dragged in the troughs and wheelies were predictable and easily controlled.

Gybing was fascinating as there was so much variety on offer.  I could bury the full rail for a drawn our slalom style turn or snap it around quickly off the back foot.  Alternatively, I could use a combination of the two which worked well in the lulls - Fast entry with a sharp tail turn after the rig flip to enter the new tack squarer to the wind.  Also since the board planes so early and the straps are free from the flow I was going a slow as 8 knots on the exit and remained on the plane.

The board is made solid and there is a bit of extra weight in twin delta stringers, this board is made to last and take the punishment of the chop and my local.

Needless to say, I can't wait for my next session closer to the middle of the boards sail range.