Wednesday, November 6, 2013

Cutting the main hull panels

Just one more hour in the shop this evening to cut the main hull panels which we drew last night. But first we drew the floor stringer line heights on the top panel and transferred them to the bottom one drilling small holes through both. Here's a view of the half done work

while here's me cutting the sheer

and finally a view of the complete main hull panels still stacked and screwed to the table

Those panels are big for sure! Finally, the various sections were unscrewed from the table and set apart.
Tomorrow we'll fly to Japan for a conference and will be back in a couple of weeks.

Total work time to date: 20 hours

Drawing the main hull panels

Two hours of work last evening. We cut to size, stacked, aligned and screwed to the table 6 plywood sheets in 2 layers for the two main hull side panels. Alignment needs care, and we used a laser pointer to make sure that the sheets were properly aligned. This is important because we use the long side of the sheets as baseline for the measurements... Once the alignment was called good, we drew the panel shape using the measurements given on the plans. The curves were smooth enough without any adjustement. Tomorrow we'll cut the panels, and then we'll stop for a couple of weeks due to a business trip in Japan.

Total work time to date: 19 hours

Sunday, November 3, 2013

Cutting the ama hull panels

3 hours of work today. Cutting the panels took about two hours. We used our small circular saw with a 85 mm diameter blade. The laser pointer helps to cut precisely, but the cutting speed is slow and okoume' sawdust flies everywhere: however we both wear glasses and since dust masks are very uncomfortable we do not use those.

By the time we had just started to cut the second panel, the first blade went dull and started to produce smoke and darker sawdust, so we replaced it.

The new blade allowed us to complete the cutting operation. We also tried to use the big circular saw, but it's a bit scary and more difficult to control so we went back to the small one. Here's an "aerial" view of the ama hull panels, completely cut but still screwed to the table while the offcuts have been removed. On the left are the two stacked outboard panels, on the right the two inboard ones. Remember that we cut all ama panels in one operations, so what you see are actually all four ama hull panels (two layers per side).

All section have been marked, unscrewed from the table and set apart. Then we spent about one hour to clean up the shop and put the remaining 6 mm panels (6 of them, again in two layers) on the table, ready to start the main hull panels. Here's a bunch of plywood offcuts at the end of the day:

Total work time to date: 17 hours

Friday, November 1, 2013

Drawing the ama hull panels

November 1st is an holiday in Italy, so we managed to work 5 more hours. Following the building instructions and the plans, we cut to the specified lengths 6 plywood panels (6 mm thick), aligned and screwed them on the flat out table, stacked in two layers. Here's yours truly cutting the plywood with a noisy small circular saw.

In such a way, one draws the panel shapes on the top layer only, and then cuts through both layers. The ama hulls are asymmetric, so the inboard and outboard hull panels are different. Here is the whole lot already aligned and secured to the table top. This operation took a bit longer than expected since the plywood panels might not be exactly identical, so butting and stacking needs quite a bit of adjustments before screwing everything down.

Next step is drawing the shapes of the panels. This involves drawing the stations and then marking the specified heights (sheer, chine) on each. Then, using a spline (we used a 2 cm wide strip of 12 mm plywood) touching small nails driven in the plywood at each height, the curve is first checked for fairness (we had to move one point by about 2 mm) and finally drawn on the plywood. Here's Cinzia at it

At the end, we have two nice fair panel shapes ready to be cut. By the way, looking at the size of these panels one starts to have an idea of the size of the boat! Here is the aft end of the ama panels, both the inboard (top) and the outboard (bottom). Those panels are almost 5.5 meters long!

Total work time to date: 14 hours