Building Logs

Glassing inside of davits.

Posted by Paul

I had some visitors early so I got a later start to work today but I still managed to get all done that I had set myself for the day, I just finished a bit later than I otherwise would have. Today’s task was to set up the davits (screw the fronts to the sides) glue, cove and glass them.

It was warmer than it felt as I had a pot of resin go off before I had a chance to use it but other than that it was a fairly uneventful day with everything else going to plan. It is surprising how long it takes to do this work. I cut the glass (3 strips of 500g uni off a tape roll already 100mm wide) and 2 layers of 450g double bias for each davit, one for the base layer and one for a covering layer (uni needs to be covered with a layer of double bias to stop its strands from wanting to lift under load) and this did not seem to take long. I filled all of the kerfs with glue and buttered the davit sides (one at a time as I knew it would take too long to attempt to do both at once) then screwed the front back down onto the sides and cleaned out the excess glue that came out of the kerfs and side joins and used it to start filling the kerfs on the second davit.

Once both were glued I had to keep working so that the glue would not harden before I got the glass on. I coved the inside joins on each side of each davit. Again each cove must have taken 15 minutes meaning another hour had passed. I then started to wet out the first strips of glass. I decided to glass each one with the first layer of double bi so as to be sure I had a wet on wet join onto the kerf glue and coves. It had been nearly 2 hours since I put the first glue into the kerfs and it was starting to rubber up a bit. Once each side had the first layer down it bought me enough time to go back to glassing one davit until finished before starting on the second.

davit glassed insidedavit glassed inside 1

The davits will have the lifting line go over a block at the end and travel inside the davit to another block that will have an exit point on the front of the davit so you don’t have to lean out to the down line to haul up the dingy. In order to do this I need a slot in the front of the davit. But the strength for the davit comes from uni running along the front (mostly outside but some inside) and the slot will considerably weaken any uni strands it cuts. To get around this I have run one uni tape along the side wall and front over the cove each side of the slot and the third layer of uni I have run down the middle of the front but cut a slit in it and separated the strands where the slot is so that they wont be cut by the slot, maintaining the uni strength. The final tying layer of double bi finished each davit.

Because I started a bit later and because again I had worked through without stopping for lunch I was quite tired when I finally finished the last cover layer of double bi. I really should have put a layer of peel ply on too but peel ply is a bugger to get around curves as it does not sit nicely so I got lazy and decided I would sand the inside of the davit and give it a finish coat of white epoxy. The davit will also have a back glued on so the inside wont ever be seen, but I will have removable lids in the back over the block so that they can be got at if any maintenance is needed. I will also need a floor and drain for any water that gets inside the davits to drain out.

Next step is to glass the outside including even more uni along the front face and maybe some down each side, but uni does not like to go around curves against its strand direction easily. The davit sides are a fairly gentle curve though so I think I can get some light uni layers on without it bunching on the inside of the curve (shorter than the outside). Another good days work done and a good weekend. Getting the steps sorted was a relief as I was a bit nervous about having to design them from scratch. I think hey work well and look pretty good. Because I am going all the way from bottom step to hull top the steps have to climb a long way (the fusion for example has walk thru transoms so only needs 4 steps, whereas I need 8 to the decks and 6 to the walk through duckboard height) but even so I still think they look ok.

I also finished this week on exactly 2222 hours counted so far.

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