Friday, March 11, 2011

I have a mast!

Still not finished of course, but at least now it's in one piece.  Here's a summary of what happened the last few days.

The picture of the tube for electrical wiring (anchor light, VHF antenna, maybe wired instruments; I was thinking Tacktick, but inquiries to the factory, the importer and the dealer in Norway, British and American dealers as well as people fitting out carbon sports boats with the system have left me with none answers to the question: Does it work in a carbon boat?)

Mast socket plate with cheek block for main halyard fitted in aft mast half.  Centre web fitted to the cup containment area. A pilot halyard was threaded before glue join.

The probable profile of the lower part of the mast

The shroud attachment tube seen inside forward mast half

The lower centre web being glued to the aft mast half, using the front half as a pressure distributor when compressing with straps.  At the same time I dry fitted the upper part and glued the two front half parts together with microfibre saturated epoxy in the gap and a couple of patches on the outside.

The inside lamination on the front half join heat curing while upper centre web is prepared for glueing

The upper centre web glued in place, compressed as the lower one.

For those interested in the details: The cut off from lower part of the front half, showing the profile, the pre formed flange and the recess for unidirectional fibres as well as foam in low curvature areas in order to improve panel stiffness and avoid buckling under compression.

Centre web prepared with microfibre saturated epoxy for joining, and the forward half with pilot halyards threaded.  Ready for joining.

Joined.  Compression.  One problem arose; the two halves are not totally rigid, and being unable to get inside to expand the profile at the join, the front half ended a few mm narrower over parts of the mast.  This means the bed for the UD will not have a totally even surface, and the exterior will need some fairing to leave a smooth shape.

The shroud tube openings beveled.  I laminated with a light carbon/kevlar hybrid to maximize chafe resistance, then inflated two balloons inside to keep it tight while curing.

I will spend a considerable amount of time working this week end, but hopefully I'll be able to remove the mast and get on with the hull during the week end. I have to pray for a couple of days with weather good enough to finish the mast without the heater running, as it is just too tight to get the rest done in the workshop.


Guy Waites said...

Congratulations Tor,

Super work on your new spar!

Dag said...

I am joining Guy! This is a milestone Tor.


MartinF said...

This is going to very well build mast I guess. Instead off Tacktick you could have a look on Velocitek Prostart. I got the older model and it can show you the same as Tacktick but also VMP (velosity made good) as it is based om GPS. See new model here: and here:

Tor Rabe said...

Thanks, I've been looking at these (the old model). Big drawback with the new one is it doesn't show VMG anymore!