The work continues on the halyard guide, something I can be doing without going into the cockpit and, potentially, spoiling the new varnish. Some tasks will require work in the cockpit but I'm hoping that I can do this without touching the new varnish. For now, however, the halyard guide is one of today's tasks.
The halyard guide being glued together. The pieces were cut out from marine plywood using the test shell as a guide for the size and the gap made slightly too small for the sheaves.
Here I am sanding the guide to fit the camber on the coachroof. The guide at this point has been sanded, the corners rounded and the two bolt holes drilled. The 40 grit sandpaper is laid on the coachroof and the guide moved from side-to-side. Since the sandpaper lies flat on the camber the bottom of the guide quickly wears away where the camber is highest and the bottom of the guide becomes curved to fit the camber.
As you can see from this photo. I could sand it a bit more but with some sealant under the guide and screws in the ends the slight remaining gaps at the end will be filled in.
The bolts being used to hold in the sheaves will have Nyloc nuts as the bolt does not need to be tightened down hard, just enough to the bolt from moving. However, the heads of the bolt need to be recessed into the bottom of the guide so that the guide still fits flush with the coachroof.
There are two ways to achieve this. The first is to recess a hole into the wood that is big enough to get the head of an 8mm spanner in to allow the nut to be tightened and the second is to drill an 8mm recessed hole in the bottom and then hammer the bole home. The second method is what I have used as you can see from the photo. The 8mm hole is not quite large enough for the "corners" of the bolt head so they are forced into the wood and hold it firmly.
A spacer is used between the top and bottom so that when the bolt is hammered into the wood it does not damage the wood or the glued joint as the force is transmitted through the guide and onto the rest upon which the guide was placed before hammering.
Here is a close up of one of the holes and you can see how the flat sides of the bold head have forced the wood to adopt the shape of the bolt.
Moving on, the guide now has the edges of the slot rounded over and the mounting screw holes drilled and countersunk. Here it has been fitted into position and you can see that it is a reasonably good fit to the camber.
The guide is mounted in the same position as the two bullseyes since this is also where one of the beams under the coachroof lies allowing the screws to penetrate through the coachroof itself and into the beams.
Whilst the outer part of the guide will be painted with the same deck paint as has been applied to the coachroof, the inside needs protection that will not reduce the width of the sheave slot. To achieve this I masked off the slot and coated the interior with an exterior grade wood oil from Cuprinol. Once that has dried I will paint the underside of the guide after the sheaves and bolts have been fitted.