zaterdag 26 april 2008

main hatch 2

Sawing the front end of the main hatch (angled 45 degrees). After that I screwed a piece of foam to the edge to act as a mold plate, and laminated the inner front side with a big filet in the corners to be able to sand a nice radius in the corners before laminating the exterior.
End result (roughly cut)...
Other angle....

dinsdag 22 april 2008

Main hatch part 1

I'm using the hatch cutout-section of the deck to make the hatch. This seems much easier than making a hatch from scratch.
First step is to glue some foam round the edges to get to the required size.
After that I made a mold to laminate the sides and aft side of the hatch. This leaves me some time to think of a way to mold&laminate the front end of the hatch.
Sides & aft-side laminated. Finally something other builders might consider: in the plans the deck stringer is positioned almost against the hatch coaming. That may be the strongest solution, but might be difficult to laminate & get fair. After seeing the picture on the site of Oliver Doms of the coaming-stringer edge I decided to make the hatch cutout 1 cm less deep to get a bit of working space between the coaming and the stringer. Guess this won't hurt the 'integrity' of my boat.

zondag 20 april 2008

side faired and windows cutout

After glassing the wingnet tubes I could start to fair the cabin sides. First step is to put on some lines of putty with a candybag, and sand them flush to act as a guide for putting on the main layer of putty.After that the putty is put on. I do this in two layers (second layer when the first layer has not totally cured), as the first layer is usually a lot lower than the guiding lines. After that sanding with diagonal movement of the sanding board. I was afraid the laminate of the wingnet tube would be hard to fair, but that turned out to be very easy.
Got to get the hang of the fairing a bit again. I put on a too thin layer of putty. While fairing I (almost) sanded through the layer on a couple of spots too quickly, making it very time consuming to finish the sanding in these areas (got to be very careful round these spots).
To mark the 2,5 cm overlap of the window on the hull it's easiest to just hold the window template 2,5 cm lower and mark the cutout line.
Final result...
I will first fill the edges, and then sand them to get rid of some small jigsawing-swaying.
In the process of cutting out parts for this boat I have ruined countless jigsaw-blades - till now. I switched to using an abrasive jigsaw blades in stead of normal blades, and this works perfect. I read this tip on the tips&tricks section (plywood/glass) of Michael Leneman's site

maandag 14 april 2008

forward bulkhead flange + window templates

I used some leftover divinycell foam to make the mold for the forward beam bulkhead flange. Worked OK, you've only got to use the heat gun a bit to form the lower corner. After laminating the flange I'll use the foam to double the cockpit floor. Trial fit of the templates for the windows. Plans state they should be placed vertical in the middle of the flat side..... ehm right...which middle? We decided to put the aft end of the aft window in the middle, and keep the lower end of the windows parralel with the gunwale line. The windows are about 3,5 cm above the level of the top of the beam mounts (I scribed this line on the hull with the laser level this weekend).
NOTE 20/4/08: the vertical line on the picture below is the position of the main bulkhead. When cutting out the windows I decided to put the windows about 3 cm further back than shown on this picture, as the front of the window was a bit too close to the beam mounts to my liking.I find it difficult to judge if the windows are in the right place. I'd like to stand back a little further, but that's not possible in my workshop.

When I'm satisfied with the place of the window-templates I'll drill some holes to mark their position and then first fair the cabin sides before cutting out the windows.

cabin floor + wingnet support tube

I've been doing a lot of small tasks lately (finishing taping etc.) with no visible progress. Yesterday however me and my brother Hans got some new items done....

In the centerboard version of the F22 putting in the forward cabin floor is mandatory. I preformed a flange on the 'front' of the floor....
...and used some cheap&light foam to form the other gluing flanges (same trick I used for the cockpit coaming). This week I'll put the floor in.
With the beam mount laminations complete we could continue to glue the wingnet support on the hull. I'm going for the 'tube' option - maybe a bit more difficult to fair, but much cleaner than mounting a support with a whole row of bolts through the hull.
We first tried to locate the position of the tube by guesstimating where the gunwale edge should have been (the edge is gone because I had to round it prior to laminating) but this didn't work very well. Luckily I recently bought a not too expensive laser level - this worked perfect.
Tube in place with some temporary screws and fixed with dots of glue. I'm fitting a tube for the optional bow net as well.
First pass with putty and almost ready for laminating.