Monday, March 31, 2014

Main hull, port panel (3)

Just one hour today.

We first unscrewed the panel from the table. It all went smoothly.

We then closed the holes on the external side with tape to be ready to fill the screw holes with epoxy. This is a big panel!

Total work time to date: 83 hours

Sunday, March 30, 2014

Main hull, port panel (2)

Just one hour today to glue everything else

Total work time to date: 82 hours

Saturday, March 29, 2014

Main hull, port panel (1)

Six hours of work today. We spent about one hour to grind off the epoxy drained through the screw holes of the ama inboard panels, which the masking tape was not able to stop. We then turned to the first of the two main hull side panels. The main hull panels are mirror image of each other and we started with the port side.
Here are the three sections aligned and screwed on the flat out table

We then prebored the stringers on 30 cm centers, prepared the thickened resin (we used 350 gram plus thickener), spread it on the gluing surfaces and screwed down the stringers. Here's Cinzia spreading the glue for the sole stringer.

By the way, one drawing in the plans shows that the sole stringer is screwed from the outside, but the building method does not allow it for now. We won't use those screws at all, both because the epoxy glue is so strong, and because the sole stringer is also supported by the vertical stiffeners between it and the bottom stringer.
Here is the panels with all stringers glued and screwed down.

Finally, we cut to size and prebored the butt blocks, the vertical stiffeners and the bulkhead landing stringers. Since we use 5-ply plywood, we can avoid the upper vertical stiffener (between the sole stringer and the deck stringer).
Here's a view of all this stuff ready for the gluing (which we'll hopefully make tomorrow).

Total work time to date: 81 hours

Friday, March 28, 2014

Filling the screw holes

Just one hour last night to fill the screw holes (the photo shows Cinzia at it with a syringe). We put some masking tape to close the holes on the plywood side of the panel (you can see it in the previous photos), but is some case the resin seeped through...

Total work time to date: 75 hours

Tuesday, March 25, 2014

Much better this time!

It went much better this time. Last evening Cinzia worked one hour (alone) at the boat: all screws came out without any problem, and the plastic sheets covering the table worked just fine in preventing adhesion. This morning we stacked the panels face to face and they are indeed identical to within 1-2 mm. Note the large bevel at the keel stringers.

Total work time to date: 74 hours

Saturday, March 22, 2014

Two more panels done

Six hours in the shop today. We completed the two inboard ama panels in a significantly shorter time with respect to the first two (outboard) ones: experience pays! This time we cut a few corners: we did not do a dry run first, but instead we first glued and screwed down the longitudinal stringers. Then we cut to size the stiffeners and finally glued them down. We prepared about 750 grams of epoxy resin and thickened it as usual with microfibers. Here are some photos.

Anything may come of help when drilling holes on 5+ meter long stringers (that's my bike btw)

Here's Cinzia spreading the epoxy glue with a brush

and here's how the thickened resin looks like

Here's Cinzia again while we were measuring and cutting to size the stiffeners.

And here we go: everything done!

Total work time to date: 73 hours

Saturday, March 15, 2014

Hull panels again (ama hulls, inboard panels)

Two hours of work today. After finishing the work on the stringers (ripping and cleaning), we cleaned up the flat out table and started assembling the two ama inboard hull panels. 

Here's Cinzia taping the plastic sheets to the table top

here are the various panels laid down on the table

and this photo shown the panels and stringers pinned down to the table 

Total work time to date: 67 hours

Tuesday, March 11, 2014

Tids and bits

We worked a couple of hours in the last two evenings, mostly to repair a broken scarf joint, remove excess epoxy from the scarfed stringers, and so on. We discovered that the epoxy/microfibers mixture must be much thicker than we thought: something like thick mayonnaise (we do not have peanut butter available around here!), so the correct ratio in volume between resin and microfibers is more ore less 1:1. Gluing is much easier this way: no voids, no runs.

Total work time to date: 65 hours

Saturday, March 8, 2014

More stringers

3 more (boring) hours in the shop today. We removed the first couple of panels from the table, ripped new stock for the stiffeners and started to make the thicker beveled stringers for the main hull bottom.
Next session we'll start to make the other two float hull panels.

Total work time to date: 63 hours.

Wednesday, March 5, 2014

Filling the screw holes

Today we managed to work 2 more hours to fill the screw holes with epoxy, using a plastic syringe and a toothpick. We counted about 80 screw holes per panel, and used about 160 grams of resin.

Here's a photo showing the external faces of the panels with all the holes closed with masking tape.

We then covered the table with some plastic sheets, turned the panels inner face up, and filled the holes. Several of them required repeated refilling (mostly those which required additional "work" to estract the screws). Here's a photo which gives an idea.

Total work time to date: 60 hours

Saturday, March 1, 2014

Waste of time, and lesson learned

4 more hours of hard work today to recover the gluing mess. The day has been devoted to grinding away the chunks of particle board which were ripped away (mostly along the plywood butt joints) and removing the several screws which had remained glued into the stringers or butt blocks. We now have several fairly sized holes here and there which will be filled with thickened epoxy. Even if I had worked again with epoxy, I'm very impressed by its holding power which is nothing short of phenomenal.

Anyway, we succeeded in getting the panels quite clean with no major issues. And the most important thing: at the end of the day, we stacked the two panels face to face (they are mirror images of each other) and they do match to within 1 or 2 mm!

Total work time to date: 58 hours (but should have been 52!)