dinsdag 27 november 2007

Main Bulkhead, cockpit floor & mast support web

After taping the main bulkhead, taping the ruddermount on the inside and making some flanges I could glue the cockpitfloor. I also glued the mast support web in place (not taped yet).

Cockpitfloor flange + plenty glue

Cockpitfloor glued and temporarily held in place with woodblocks and a piece of wood between the beam bulkheads to keep the floor straight.

Mast support web tacked in place prior to taping.

As I'm almost done taping the interior panels, I have to prepare for the dreaded longboarding. I'm experimenting with a poor-man's longboard: it's just a piece of foam with one layer of tape on top and two wooden blocks as handles. I tried to glue sandpaper with spray glue, but that didn't stick. After that I used ready made wallpaper glue: this works ok but takes a while to set enough. If the longboard works well, I'll make a few so I'll never have to wait for the glue to set.
Once I've done some sanding I'll report if the longboard works. I hope so: it's cheap to make and VERY light.

vrijdag 23 november 2007

Bunktop & Rudder Web

The second half of the bunktop has been glued in the hull. First I had to make a flange in the most forward section, as the underside of the top can't be reached in this spot. I was in doubt if it would be easier to use the alternative for a flange as described in the plans (drop panel in a bead of putty and tape the underside and upperside of the panel only 'up') but decided it would probably be stronger to form a proper flange. This turned out to be much easier than I thougt (nearly straight section).
Flange mold...

Second half of bunktop glued in place. I use wooden blocks with screws to temporarily fix the panel. The screw-holes will be filled while taping the joints. It is very satisfying to put these large panels in the hull - it really makes a big difference in the way the hull looks on the inside.

Glueing the ruddermount with a level to check it's ..ehm..level. It's held in place with some wooden sticks, one screw and the tube (which is held at the right height with a piece of wood clamped to form frame 12).

My plan is to do all the internal taping of the ruddermount before placing the second cockpitfloor panel, instead of doing it later. To me doing it now seems much easier than trying to tape the mount through a temporary hole in the cockpitfloor (as per plans). Or am I missing something here?

dinsdag 20 november 2007

Internal taping

Most of the internal taping and extra laminates have been done now. Instead of using peel ply I experimented using plastic on top of the fabric.
First impression:

  • it's very easy to see where there's air in the laminate, and its very easy to get rid of the air by squeeging the bubble to the edge of the plastic;
  • it's difficult to know for sure, but to me it seems the cloth is much more 'compact' and well adhered;
  • after removing the plastic the surface is very smooth with the weave (almost) filled; it will probably be easy to sand it without sanding too much into the cloth;
  • unlike working with peel ply it's easy to see what is happening to the cloth;
  • the edge of the cloth blends in very nice;
  • the plastic-trick works for flat surfaces and doesn't work in corners (can't plie it without a lot of wrinkels)

The first results are encouraging and I''ll go on using this technique. For now I only used it to laminate on top of already sheeted foam, I'm not sure it will work as well on bare foam. We'll see.

I tried to take some nice pictures, but I wasn't able to get very good ones.
Posting them anyway....

deck stringer glued to roof
laminated with UD + C + P(lastic)
plastic removed
foam bedded for placing rudder web
Laminating the last layer of cloth (UD) on the rudder web, this time in an ordinary garbage bag, heated to speed up curing

woensdag 14 november 2007

Bow and little things

Unfortunately I did not make much progress this week. I've been busy closing in the bow with foam and taping that section. Not much fun: difficult working laying twisted inside the hull. Luckily it's done now. Before I can fit the second half of the bunk top I have to finish the bobstay anchor.

Bobstay anchor: foam with putty insert.

Bobstay anchor: middle section cut.

Bobstay anchor: wow, that is a lot of carbon!
Laminating the bobstay anchor wasn't a big succes. Laminating ('wrapping') pieces this small is still not my cup of tea. To continue moaning: the fit in the hull wasn't very good either. But it's no use crying over spilled milk. Currently the final layer of C is curing so tomorrow I'll glue the anchor in place and be done with it. I decided to try use vacuum to force the last layer of cloth tight around the piece. I used an ordinary shopping-bag and a tie-wrap. This works really well.

poor man's vaccum bag?

I'm also working on the rudder web. I made two jigs to glue the gudgeons exactly alligned.

vrijdag 9 november 2007

Hull joined!

When trial fitting the hull-halves I noticed some gaps, especially in the bow section (ranging from a few mm to app. 1,5 cm). Maybe the upper half distorted a bit because I was not able to support it much (as I had to lift it out of the way), or maybe this will always happen a bit in the areas where there is some tension in the foam and the marine ply insert (because of all the bending).
Luckily this didn't turn out to be a problem. To be sure of a very tight join, and for ease of mind, I thought out a way to clamp the halves together. Here is what I did:

On the outside of the upper half I screwed a batten along the whole joint, held in place with scrap piece of wood which overlap the joint. See the picture below. In the bow section I couldn't use woodblocks, so I only used screws (the joint is not flat in this area). Picture of the extra batten on the outside.
The preparation took about one hour (taking it easy mode) and was well worth it. After putting some putty on the joint it was simply a matter of clamping the battens together - 2 meters at a time, starting from the bow - and correcting any misalignment by screweing some extra blocks to the outside batten to pull the battens in line. See the picture below. By the way: this part had a gap, and needed more clamps than usual.
After aligning and clamping the battens together, I fixed them with some screws and went on clamping the next two meters. The whole process only took about one hour (taking it easy mode).
Result: an IMO very nice joint.

maandag 5 november 2007

We 2 are almost 1

Trial fit of the two hull-halves. A plunge bob is used to put the halves straight on top of each other. I used the beam-bulkheads at gunwale level as a reference point, as they are by far the most accurately placed parts in the hull halfs.
Impression of joined hull (rotated, of course). Looks quite roomy for a relatively small boat.

Bow web - part 2

Laminating the bow web. I did the first layer with one piece of DB. Not a very good idea (duh), just too much curves and overlaps to wrap it nicely this way. No pictures of the rest of the laminating. Let's just say 'wrapping' is not my favourite work. For the last layer I worked with several pieces of bi-axial tape (15 cm wide, I cut it in half for taping bulkheads etc.) and this went much better than the first layer. This tape is really bendable and doesn't fall apart the moment you cut it (unlike the DB cloth I used for the first layer).I screwed a piece of scrap foam to the bow and 'surformed' it level, to make a nice fitting foam insert to place the bow web on top.
I bedded the foam-insert in glue, then glued the bow web on top and used the squeezed out glue to more-or-less form a fillet on the inside. After that I taped on the inside in the still wet fillet, thinking this would give a better bond than waiting for the glue to set and trying to sand in this difficult to reach area.

I wasn't really pleased with the way the bow web looked, as it was a bit chunky and messy because of all the glass overlaps and carbon-tapes. However, after fitting the bow web it became clear how little of it will ever be visible again. Of course I knew that by reading the plan, but somehow it's different to see it right before your eyes in stead of on a piece of paper. The front of the bow web is the only 'messy' place visible. I'll tidy it up after glassing the outside of the hull.

donderdag 1 november 2007

Bow web - part 1

I can't work further on the main hull because I didn't finish the bow web in time.
Ian sent me the G10-tubing necessary for making the web. Wow, those tubes are............expensive. I guess the mechanical properties of the tubes justify their price.
I left the foam of the bow web a bit oversize to hold the G10-tube in place. After filling I'll cut it back to the correct size.
Filling complete. I only have to fill the HD-insert for the bow pole before I can laminate the web.