vrijdag 28 december 2007

Exterior almost lamiated..

Cabin side + upper hull have been laminated. Now I only need to do the lower hull and the extra layers on the keel and at the beammounts to finish the exterior laminate.
The hull is still light enough to move around on my own.

dinsdag 25 december 2007

Deck laminated

With the hull on the laying on the ground it's much easier working. This picture is prior to laminating. I made three rebated areas for glass overlap with the electric planer: two on the side of the deck and one about 50 cm in front of the beam-bulkhead.
Deck is now laminated with UD in place and plastic on top. With the help of my brother it took about 2,5 hours with preparation.

zondag 23 december 2007

Hull out of frames

The hull is out of the frames and hanging in two loops from the ceiling. Now I have to get rid of all (the remains of) the battens and frames and strongback before I can put the hull on the ground and continue laminating.
I'll glass the deck first, so I can turn the hull upside down without risking damageing the foam.

vrijdag 14 december 2007

Job done

Laminating the lower half of the hull in one go took me 5 hours without any break. Over all I'm quite pleased with the results. No bubbles and as far as I can judge a good resin-cloth ratio.
This is the quality of the laminate I was aiming for.
However, on some spots I just couldn't get this quality. For some reason the cloth kept some wite-ish small spots, no matter how much epoxy I added. The cloth is laying flat against the foam, no bubble. This problem (or is it?) has occured on all laminates till now, pre-wetted or not, pre-coated or not and with and without peelply and plastic. I think it looks a bit like the 'bad' spots Grant (see link section) found when laminating with peelply and plastic.

donderdag 13 december 2007

That is a lot of glass!

Foam pre-coated with a thin coat epoxy (hull-half took one kg epoxy). Carefully sanded 80 grit with orbital sander. Vacuum-cleaned (twice) and cloth is already laying in place smooth. All heaters in the workshop have been turned on this morning to get and keep it at 20 degrees celsius.
Now I only have to take the afternoon off from work and properly wet out this 9 square meters of cloth within 4 hours. Easy enough..........hopefully.

maandag 10 december 2007

First exterior laminate

Cabin side + gunwale area + part of deck are laminated with plastic on top. On the deck I made a rabbet with the electric planer as this is supposed to ease the fairing of the overlap of the cloth. Although I'm not really convinced it is necessary in this spot (deck will need a lot of fairing anyway because of the extra layers glass) it's not a lot of work on a flat surface like the deck, so I decided to go along.

Here is the laminate with plastic in place....
...and here the plastic is removed. The 'plastic without peelply-technique' results in a very smooth shiny surface with the weave of the cloth filled. It's not difficult to sand it 'dull' without sanding (too much) in the fibres.
Lesson learned: don't try to 'plastic' multiple-curved surfaces with one big sheet of plastic, or you'll mainly be busy trying to get rid of creases. The creases fill up with epoxy, leaving a ridge after removing the plastic. It's much easier to work with overlapping 70 cm wide pieces of plastic. Luckily it'ts easy to remove the ridge.
I'm happy using the 'plastic' technique (not a single bubble this time), although like with most things it takes some practice.
Some lessons learned the hard way:
    • It's still important to wet out and smooth out the cloth as well
      as you can before putting on the plastic: with the plastic on it's easy to get rid of small imperfections and air-bubbles and excess resin, but NOT to shift the cloth in a major way, and
    • I hoped it would be possible to use the 'dry-method' with plastic, but that didn't work. On the spots I didn't pre-wet I still had a hard time to get the cloth well adhered to the foam: it just doesn't tack to the foam right away on all spots, and adding more epoxy is of no use. Does this sound familiar to other builders using divinycell? On spots with putty/ply I don't experience this problem. So it's obvious: I should build a ply stich&glue boat!
      Now serious: I'm planning to see if it helps to coat the foam with a thin layer of epoxy and let it cure before laminating so I can use the 'dry method' for the lower hull half exterior.

vrijdag 7 december 2007


Working hard to get the hull ready for sheeting.

I'm pre-filling the edges of the anchorwell hatch with putty. My idea is this will give a better result than digging out the foam after laminating and cutting out the hatch. I intended to use a router to dig out the foam, but couldn't because aera in the forward section is not flat.
Instead I used a screwdriver: I 'cut' the inner and outer outline by pricking the screwdriver in the foam and then it's very easy to dig out the foam. Maybe it would have been even easier to cut the outline with a knive or chisel, but I didn't think of it. Anyway, this was much easier than using the router. Why do I always forget to do it the simple way?
Next photo's show the way I rounded the edge of the deck to the cabin side.

Marking lines at 2,5 cm from the edge. I tapered (??) the flat area a bit at the front of the cabin to end up about twice as small at the start of the cabin-deck edge.
'Fire up your planer' - to make a flat side
Two more flat areas are planed on the edges of the first planed flat area. The 'rounding' now consists of three flat areas. I tried to mark the outline of the two new flats, but that was pretty useless (not accurate enough)
Finishing: sand the four edges of the three flats down a bit, then round the whole edge with diagonal strokes of the longboard (lonboard of course in line with the edge). It came out pretty decent. Maybe some small highs and lows, but I can't fix that in this stage. The foam is too soft: when I fix one spot I'll probably sand a bit too far on another spot of the edge. I'll get it totally right when fairing the exterior with putty.

maandag 3 december 2007

Starting exterior

The last interior panel has been taped. I'll leave the interior for now until I can put the hull upright.
I had forgotten how easy it is to sand the foam (using grit 40). It's actually quite nice and quick work. My twinbrother sanded most of the lower half of the hull in one afternoon. The bow stilll needs some work. By the way, the foam-strip-longboard (see foregoing post) works ok, but so does a much more rigid longboard I made from a two-side laminated foamstrip.
Centerboard case has been trimmed with an electric planer to roughly match the hull. First I'll fill all the gaps, then I'll sand the last bit with a longboard.
Yet another picture of the sanded hull....
I'm also starting work on the deck. In the cutout-areas of the deck I'll put some putty in place before laminating. Afterwards I can just cut the section without having to dig out and fill the foam-edges. Here is an example of the pre-filled edge for the hole in the bow. I use a very accurate festool router to remove approximately 19 mm of the 20 mm foam thickness.

Next I'll have to round the edges of the deck to the cabin-side and the hull. The plans state it can be well rounded, but how? Should I do it just with a longboard and some guesstimating (flatten the corner with a longboard - I mean: sand the corner down to for instance a 3 cm wide flat ridge and then round the two 'new' corners with a longboard)? Or maybe I can do the edges with a piece of PVC-pipe with sandpaper glued within, but it might be difficult to get a nice even corner on a long stretch.
If anyone has a good trick or tip I would be really glad.