Sunday, 15 December 2013

Not a five minute job....

The centercase is finally assembled and glued up.... this is a complex bit of kit and it takes quite some time to get it together.
First I found myself struggling to source the 40x70 hardwood logs... I ended up finding out that a neighbour living a few houses from mine runs a fine supply business for all sort of construction and joinery wood. He cut my logs from some nice sipo  mahogany he had in stock.

The inside of the case is epoxy primed then glassed before a further coat of epoxy is applied. These areas will be exposed to water and potential surface scratching as the board is lifted and lowered.
I also spent quite a bit of time figuring out my lifting mechanism (see previous post). In addition to that, before you can safely go on and seal the box you have to have the centerboard itself made to make sure it fits and swings correctly as intended.

All in all quite a bit of work, but I am pleased with the result.
You can see the slots routed in the forward log that will house my pulley based lifting mechanism. I "scavenged" the 35mm pulleys from some Barton blocks I purchased on eBay.

To support the centerboard pivot I opted for some brass oarlock sockets that are permanently epoxied to the box' sides. They are made to take a 14mm stainless steel pin; I will use two brass plugs with o-rings at each end to seal out the water.

The centerboard is now built as well (see previous posts). Today I drilled a 35mm hole where the pin goes and subsequently filled it with thickened epoxy using a high density additive. I will drill the 14.5mm or 15mm whole for the pin at a later stage.

Next is moving further aft preparing frames 5, 6 6a and the transom.... not too much to do there, just pull out the CNC precut frames and add the doublers (seat supports, etc.) as detailed in the drawings.

P.S. : ... back to the centrercase: there is a slight error in the dimensions qoted in the drawings for the seat and deck supports to be glued each side of the box. I figured out the right ones using the corresponding heights in frames 3, 4, and 5