Tuesday, March 9, 2010

Vega Standing Rigging Overhaul.

I've finally decided to address an item on the boat that's been concerning me for some time: replacement of the forestay, hidden for years under an ailing and worn out CDI furler.

After removing the old furler I decided I didn't want it back on, so spent some time researching and decided on the Harken MKIV Unit 0 model.
My rigging wire appears to be the original sized 5mm diameter 1x19 stainless steel wire. The nearest size to this is Imperial measure  3/16", which is slightly smaller, hence weaker. Given the fact the wire is completely enclosed by the furler foil, and subject to more strain with the weight and windage of the furler,  I chose to upsize to 7/32" wire.

I've always wanted to try swageless fittings for the wire ends, as they make it possible to repair rigging in the field (ocean?) without extensive tools. More research here convinced me that Hayn Hi-Mod fittings fit the bill.

They have re-usable innards, and a unique crown ring that holds the outer wire strands perfectly even in individual grooves.
Unfortunately they arrived with the wrong sized crown rings, so I've been busying myself overhauling the rest of the standing rig, while I wait for the correct ones to appear.

I discovered a cracked spreader hound on one side, so replaced both sides, promptly supplied by Steve Birch in the UK. It's amazing to still get parts for a 40 year old boat ... thanks Steve!

From  posts on the Albin Vega Yahoo Forum it seems the early (gold-coloured mast) Vegas were fitted with rigging turnbuckles with 5/16" pins and rigging eyes on the wires with 3/8" holes. The mast tangs are the same: 5/16" pins into 3/8" eyes on the wires.

I read somewhere that this causes "point loading" because the pin is smaller than the hole, and can reduce strength by as much as 15%.

Now I realize the boat is almost 40, and the rigging has held up well, but when replacing things it gives me a warm fuzzy feeling to do it right. I know it's definitely a "no-no" to simply drill out the tangs and turnbuckle jaws from 5/16" to 3/8", as this would weaken them further.

So I've compromised by installing bushings through all the 3/8" eyes to reduce the hole size to 5/16", so the pins are now a good fit. This was easy to do as I found some SS tubing of the right size, and just had to cut it to length on the lathe.
When the rest of the wire gets replaced I'll install new turnbuckles and tangs with 3/8" pins.

Meanwhile, let's hope those crown rings arrive soon ....

No comments:

Post a Comment