Wednesday 23 December 2015

Varnish

Varnishing isn't easy. It takes a while to get good results. The good thing about it is you can always just apply another coat. I think I'm getting better at this, after (thinks!) six coats on my rowing thwart, I've got a reasonably good recipe that looks set to provide a tolerable finish, at least after a few more coats...

My ingredients are Feast Watson spar varnish, Penetrol and real gum turpentine to help the stuff flow, and a proper varnish brush, which is wide and very thin, so it doesn't hold too much varnish, with super smooth bristles, so it doesn't leave great big ugly brush marks. I'm thinning the varnish out with ~15 percent penetrol and a further 5 odd percent turpentine. That gives me a mix that flows out nicely. Of course that's a recipe that's highly dependent on environment, brush, technique...

I started sanding with 180 grit, but found 400 works better in the latest coats. Here's the rowing thwart thus far. There's a bit of general lumpiness but the gloss level I'm getting is fairly good:

My rowlock bases and tabernacle have had a couple fewer coats. In the case of the rowlock base that doesn't seem to be an issue, but the tabernacle still needs some love.

I find when I'm putting it on it's good to keep a little container with mixed varnish+penetrol+turps, plus one with half an inch of pure turps in it handy, so I can thin out and clean the brush periodically, to keep it from sticking to everything.

Sunday 20 December 2015

Camouflaged cat is camouflaged.

See if you can spot the cat hiding in this picture:

Of course like all good cats, Mogget's goal in life is to ensure his paw prints are in all varnish.

Saturday 12 December 2015

Finished the coamings

After gluing the coamings in place, the next step involved trimming them so they were the correct size. This involved a process not-unlike trimming my fringe. Take a little off one side, look at it from afar, take a little off the other side, look at it from a distance, take some more off... Luckily I managed to stop myself before I reached the deck.

Then I sanded things smooth, coated with epoxy + filler (this 4mm ply has a pretty crap open-grained face ply, which swallows epoxy), then a couple of coats of unthickened epoxy, then sand down to 180 grit, and finally toplac paint.

Here's what it looks like tonight.

The shaped bit in the bow is to allow clearance so I can flip the forward thwart hatches over. The coaming is about 65mm above the deck at the bow, and 22mm above deck where I'm likely to sit on it.

Next job is to complete sanding the decks out to 180 grit and then paint them with top coat. No, I'm not using undercoat. I really dislike the stuff - it clogs emery way too fast for my liking.

Wednesday 2 December 2015

Metalwork!

Here's a padeye for my mainsheet. The usual arrangement for a dinghy is that one end of the mainsheet is terminated at the end of the boom. The sheet then goes through a block attached to a traveller or bridle across the transom (I still haven't made my mind up which way I'll go), then back through a block at the end of the boom, along the boom to about half way, then via another block mounted to the boom down to a block mounted to the centreboard case.

I have concerns about pulling a padeye out of the back of the centreboard case, as the loads might be fairly high, especially given that Geraldton is a windy place. It's hard to get inside the centreboard case to add a plate inside do through-bolt, so instead I'll use screws but screw into a couple of different faces, so that the screws are at an angle to one another. So here's that custom padeye so far. It mounts to both the vertical rear of the centreboard case as well as the sloping part, and will be held in by half a dozen #8 screws:

After welding with oxy-acetylene and CIG "Com-weld" filler, it looks really ghastly. I'm calling this piece "snot on bronze".

The below picture shows it mostly finished in-situ, poking up at the top of the aft end of the centreboard case - note the angle isn't 90 degrees (are they ever?).

I'm probably 70 percent of the way through the finish work. I've got to cut down to the bottom of some pits and polish it properly. Even so, from the regulation ten feet I reckon it looks okay.