Friday, January 21, 2011

Pathfinder/Chinook Progress report # 2

January 21, 2011
I have now completed all frames, transom, centreboard and centrecase. I found that rather than rely on a multitude of clamps to hold the doublers together I used cheap steel screws which I removed and threw away when the resin was set.

To assist with the speedy orientation of frame parts, when glueing, I used 12.5mm dowels through the frame and doubler.

The centreboard was made from all Tasmanian Hardwoods, mainly Myrtle (Beech) and some Blackwood.

To form the profile of the centreboard I used a design I found on another Blog, sorry I have forgotten who's. This proved very successful. The picture says it all.

I calculated that I poured 26kg of lead directly into centreboard cavity. The only problem I had was keeping the melting pot hot enough to ensure that the lead was still molten when I poured it. The singed areas around the lead are where I directly flamed the lead after the pour to better distribute the lead after the final pour.

To hang the centreboard in the case I used 16mm SS tube inserted directly into the centreboard and centrecase with a shallow rebate to hold a small amont of thickend glue. This not only holds the bush in place but seals the timber from water ingress.

To hold the 12.5mm pin in the bush I made up blank plates from 9mm ply with a gasket of inner tube underneath.

No comments:

Post a Comment