Monday, July 28, 2014

Filling the screw holes

Today Cinzia worked two hours to fill the screw holes in the ama bottoms with resin. And she discovered that in summer it's better to prepare small batches of resin, and work in a hurry!



Total work time to date: 146 hours

Saturday, July 26, 2014

Fairing the ama bottoms

Four hours of (hard) work today. First, using the power plane, we faired the bottom edges.


At a certain point we had to swap the hulls on the table because the inner side is almost impossible to work on. This allowed us to take a photo of one of the amas almost rightside up.


We rounded the edges with various Surforms and a rasp. Here's a view which gives an idea of the result


Total work time to date: 144 hours

Thursday, July 24, 2014

Gluing the ama bottoms (2)

Two more hours today to glue the second ama bottom.

The first photo gives an idea of the amount of resin squeezing out of the joint when the bottom is screwed on. This is removed and reused for the following panel


Almost done:


Second bottom on


In the meantime, we bought a new batch of epoxy/hardener (15 kg), 80 m of fiberglass tape, plus some other thickeners (silica and a light filler).

Total work time to date: 140 hours

Saturday, July 19, 2014

Gluing the ama bottoms (1)

Six hours of work today. We dry screwed the 10 mm planks on the bottom stringers, making sure they fitted snugly at the butts.


Here's Cinzia scribing the outline of the bottom panels


We then removed the scribed planks to cut them to shape


We cut a few mm outside the lines. We started with the small circular saw but the blade went dull quite soon. So we gave a try to this jigsaw which I've had around for some time but never used. Well, I don't know what that is, but it proved a badass jigsaw, probably 5 times faster than the circular saw. Cuts through plywood like butter!


Here's the whole bottom ready for the glue


We used about 700 g of resin thickened with the usual microfibers for a quite thick putty. Here's Cinzia starting to spread the glue on the bottom stringers


We wanted to be sure to fill voids (fairing was far from perfect) so we used liberal amounts of putty. Another good thing is that the bottom panels, at 10 mm thick, are quite rigid and hence "self fairing".We than prebored the planks and screwed them in sequence, using, as usual, 3.5x40 mm screws lubricated with some WD40. Quite some putty squeezed out of the glue line, which we cleaned both inside and outside. We decided to install the internal, 2 cm thick butt blocks specified for the bottom later, i. e. when we'll turn the floats rightside up. Here's the final view with the usual milestone beer.


Total work time to date: 138 hours.

Thursday, July 17, 2014

Bottom planks

This afternoon we started to prepare the 10 mm plywood planks for the ama bottoms. The exact shape and size is not given in the plans, so the various planks must be aligned and outlined directly from the hulls. The remaining 10 mm plywood (after having cut the 3 floor panels for the main hull) is a very tight fit for the 8 planks. Luckily enough we had one more 10 mm panel so we could be more relaxed. At the end we decided to cut 8 rectangular planks, each 25 cm wide by 120 to 140 cm long.

Total work time to date: 132 hours

Saturday, July 5, 2014

Fairing

Hiya everybody. Here we are again after more than one month of stop due to several trips abroad by both Cinzia and me. Today we spent 4 hours in the shop to do the fairing of the bottom stringers of the amas. There's a significant amount of wood to remove in order to allow the bottom panel to lay flat on the stringers, particularly at both ends of the hulls. We used the power plane, the various Surforms and the rasp. This work is not trivial and need attention as well as elbow grease. We checked the fairness using the hand saw as shown in the pictures below.

Here is a good spot


while this part needs some fairing


One has to be careful in order to remove the right amount of wood from the right place. In any case, the filling properties of thickened resin will take care of mistakes.

Total work time to date: 130 hours