This blog documents the modifications necessary to get seaworthy (warts and all), then the adventures (hopefully) on board our Trailer Sailer 6.1 metre Jarcat6 Catamaran, Kismet.

Saturday 10 November 2018

The Chainplate story begins

I retrieved Kismet from storage a couple of weeks ago but haven't had much time to do anything. I did investigate the chainplates though.

It turns out the a suspicion I had since I got Kismet was correct. The timber wedges supporting the chainplate bolts that are supposed to be epoxied to the inside of the hulls - aren't.

So there is a self tapping screw and one 3/16" bolt attempting to prevent the chainplate from being extracted up through the deck.



In additions, the wedge shown below used a combination of hardware and some softwood like oregon. The shorter piece is the softwood.

I guess that the shape of the wedge would provide some support as it bears against the lower edge of the timber running along the edge of the hull. Not good though.

I won't be replacing the chainplates but the plan is to add an extension and increase the bolt size to 6mm. I'll then add a second bolt for the extension. I'll increase the size of the screw as well. The screw and top 6mm bolt will join the extension to the existing chainplate strap.

The new wedges will be wider and be long enough for both bolts plus a bit.
(I'll also be sanding back the paint before epoxying them to the hulls.)

The fact that the wedges were not glued in helps me enormously as it allows me to simply make a whole new pair of wedges rather than attempt to add material to the existing wedges. I'll use about the left 2/3rds of the extension piece below (Ronstan RF47). Using the elongated hole (the very top of it) and the next hole down lines up exactly with the holes in the existing chainplate. The next hole along (about the centre one) will be the extra 6mm bolt going through the timber wedge and hull. I have stainless steel mudguard washers for the outside of the hull. I'll pre-tension the extension as much as possible when doing up the bolts.

I have had to store Kismet again but I have changed storage places and can now get access to the boat every day - about 20 minutes drive away. I am allowed to work on it while in storage (no welding or grinding or mess), so I'll be able to progress now without killing our front lawn.


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