dinsdag 26 mei 2009

Fitting folding system + floats

This will be a bit long and maybe boring post, but I thought some of the other builders would be interested in as much details as possible about my experiences fitting the beams.

Saturday and sunday me and my brother Hans worked hard to get the folding system and the floats installed. Saturday we worked on the folding parts on the mainhull which was on its trailer in the marina. Saturday evening we pulled the trailer with the mainhull to my workshop. The square in front of my workshop is used for parking cars from monday till saturday, but on sunday it's usually not occupied. So I had one sunday to install everything and move the boat again.

On sunday we started working at 8 in the morning, and worked almost non-stop till 9 in the evening. By then the boat was assembled enough to be able to bring it back to the marina (about 1 hour drive). My idea to pick up the mast on the way back was too optimistic. I'll have to drive back another time to pick it up.

First thing we did was fitting the bushes in the beam mounts. This can be easily done by sticking the bush with some double sided tape on a sawblade and use that to insert the bush in the mount.
Then we leveled the trailer (used a tube with water to level; when you do this make sure there are no air bubbles in the tube). With the trailer leveled we attached the upper folding struts to the hull and then to the beams.
This took more time than expected, because on one beam mount the holes for the bushings were not in line (see last part of the linked entry). The pivot pin would not properly go through both bushes because of this misalignment, and we had to use a lot of force. Destroyed one bushing in the process, but luckily I had a some spare bushings.
The fit of the beams in the aft beam recesses was not perfect. I had to grind one beam end back a bit to make it fit in the recess (but not as much as the line drawn on the photo below).
Because I knew I didn't have much time to install the beams I made two dummy decks of the floats (below - box sections of fir battens with cheapo 3 mm multiplex) so I didn't have to worry about the distance between the beam ends nor the twist of the beams.
I don't know if it would have been difficult without the dummy decks, but with the dummy decks aligning the beams was a piece of cake. First we put the end of the dummy decks on two ladders and put blocks and shims underneath until the beams were level. Then we clamped some battens along the edge of the dummy decks and used a rectangualar piece of mdf to check if the angle between the beams and the dummy deck was 90 degrees (see photo below).
With the level and the piece of mdf it was easy to quickly recheck the alignment now and then during the installation. I was a bit worried the fore-aft alignment of the beams would give problems as I had noticed that at least one beam mount was a bit out of angle fore/aft (it was pointing slightly to the front), and apart from that for some reason I managed to get the location pins of both floats about 8 mm too far apart. But much to my surprise the vertical alignment of the beams seemed near perfect. Maybe by miracle I also installed the beam mounts 8 mm too far apart, but more probably it's just hard to notice the few mm misalignment.

On all four beams it seems the beams are sticking out a bit too far at the beam mount, and I will have to grind the end of the beams (maybe even considerably on some beams) to make space to fit the beam end plate. Thought this part of the alignment would give the least problems and the fit would be the most accurate, but clearly it is not so. Don't know why.

The brackets all fit on the bolting area perfectly. Big relief again.

After aligning and bolting the beams+folding structure we had to hoist the floats down. This time not with a crane, but with some lines and chain hoists.
Yes I know, this is not a very smart way to hoist a float. Still the floats came down with not too many scratches.Bolting on the floats was not difficult either. We folded out the beams, put two workmates underneath the beam ends, lifted the float on the workmates and while one person held the float steady at the bow, the other put some blocks under the keel till the beam bolts stuck in the float deck at one beam. Quickly put a nut a few turns on one beam bolt and it's temporarily fixed. Then fix the float at the other beam the same way. It's not necessary the float stays level: it's possible to put the beam bolts on one side in the float deck with the float hanging, say, 20 to 30 cm below the other beam end.

After fastening four of the six bolts per beam the boat was solid enough to fold in and drive it back to the marina. I still have to glue all the brackets and beams and to fix the beam end plates.
The folding works very well, it's something you've got to see/feel for yourself to believe.
Below the boat is ready for the ride back.

Detail below: I replaced the stainless steel trailer eye by a loop of 6 mm dyneema with a knot on the inside. Easy and it seems to work well.

I never realized how wide the folded boat was at the bow end, but now I do.

Last photo: getting the trailer out was only just possible.

To conclude some lessons learned/things I noticed:

  • It's not necessary to level the boat lenghtwise to install the beams. It's sufficient to make sure the left and right beam mounts are level. When the boat is on a trailer (make sure it's tied down firmly on the trailer) this is easy: put fixed blocks under the front end of the trailer and one of the two aft corners, and jack the other aft end of the trailer until the aft beam mounts are level. Front beam mount should now also be level.
  • Bolting the aft beam compression formers with the four bolts is terrible. There is by no way enough space inside/underneath to get all nuts on with washers. I even had to redrill two bolt-holes at a *very* slight angle to be able to get a nut on. Maybe it can work out right on a computer screen, but I doubt ever in the real world.
  • Important for european builders: I thought the bolt blocks hanging inside the beam mounts would be tapped M12, but (should have known this probably) they were tapped with a non-metric thread. I had no possibility to get the right bolts on sunday, and had to turn in my M12 bolts in anyway. I probably damaged the thread too much and I will have to replace those blocks.
  • When making /installing the aft beam recess mold plates, rather err on the 'big side' because this area is tight when done properly and too tight when you make the recesses by mistake a little bit smaller than per plans.
  • It's easiest to line up the metal hardware on the aft beam mounts by first only putting in the outer bolts left and right, and then use a wire or a long straight piece of wood/metal to put the hardware on both ends exactly in line with eachother. This way you can correct any possible misalignment of the beam mounts (in case they are angled a bit forward or aft).
  • The holes on my beam brackets were all a bit less than 10 mm diameter and I had to redrill all the holes. Better check & fix this before putting the folding struts on the beams.
  • Fix your main hatch while driving. Maybe it's enough to firmly fix the front legs of the hatch. I thought the driving wind would always be pushing the hatch down, but while driving the wind got underneath and the front popped up. The hatch then acted as a big 'wind trap'. Good thing is now my whole boat has had an excellent ventialation.

vrijdag 22 mei 2009

Welding & drilling

I lend a big mig welding machine from a neighbour. Before I had only done some arc-welding. MIG-welding is much easier. Mig welding aluminium is a bit more difficult than welding steel but with a little practice it should be doable (so I'm told).
My plan was to spend a day practicing welding aluminium first, but I ran out of time. I needed to get the mastfoot + mast support ready because I need them this weekend: the boat will be assembled and moved. So after some trial welds I started on the real thing.

First part: the mast support.
Close up: bit messy but the best I could manage at that time.
Mastfoot welded in mast. It was a bit tricky welding intense enough to get the weld to penetrate both the mast and the mastfoot-plate without burning a hole in the relatively thin wall of the mast.
To drill the holes in the float (and my dummy float decks, see next post) as easy as possible I made a mold which centers on the center pins in the float deck. It can be lined up with a laser shining from the other location dowel.
Trial fit of a beam. In reality the beams look much more massiven than shows on the picture. When tapping for the saddle eyes on the beams, I missed a backing plate at three of the holes. Those holes were after consultation with Ian Farrier backed with HD epoxy mix.
Next post hopefully will show the floats two floors lower atached and working well. This weekend (today and tomorrow) me and my brother will get the main hull from the marina and install the floats.

maandag 18 mei 2009

Rig

A few months ago some of the parts for my rig were delivered. Building the mast was mostly just a matter of drilling and sawing holes and popping or screwing the parts into the mast profile. I made sure not to have any sharp corners in the cutouts, as I've read those will be prone to develop cracks. To insulate the aluminium from the steel I used silicone kit, but it would have been better and easier to use 'duralac' - but unfortunately I found out too late about this product.

The upper part of the diamond stays are anchored with T-terminals. The spanners are on the lower part and need to be attached to a tang. To bolt the tang to the mast I cut two pieces of 1 cm thick alu:


Using some solid electricity wire it's easy to drag the piece to its location....

Below the piece is bolted in place. The hole in the middle will be tapped to receive the short M8 bolt which will hold the shroud tang.
I've always tried to avoid marine shops. In my opinion they charge outrageous prices. The last time I had to go there I saw a blister ordinary type 304 nyloc m5 nuts being sold for 1 euro (about 1 dollar) for each nut. I had just bought a 500-box of exactly the same nuts at an online materials-shop for about 10 euro. Maybe most people owning a sailboat are so loaded they don't care what to pay. Or maybe they think they get superior quality, because why else would this small nut be so expensive?

Anyway, to save myself the anger of having to pay 30 euro for two tangs, I bought a strip of 4mm stainless steel for less then 1 euro and worked maybe 10 minutes:

(1) Saw two pieces and drill four holes,

(2) slam each piece two or three times with a hammer, and
(3) file the edges a bit so they're not sharp. End result is for sure not as polished and good looking as the shop tang, but it's good enough for me and I've saved the earnings of working for more than an hour at the office in 10 minutes.
The setup of the mast will be as simple as possible.
I'm thinking of putting in halyards for only the main sail and jib (jib with 2:1 halyard). The halyards exit the mast high, so I can raise the sails by hand. All lines stay only on the mast. The idea is to raise the main by hand, fix the halyard with a stopper, and then tighten the main by pulling a tackle form the mastfoot to the eye at the bottom of the sail.
Maybe I'll attach a fixed rope as a backup forestay, also because this is easy for raising and lowering the mast.
The only expensive cleat on the mast will be the stopper for the main halyard. It is bolted to a tapping plate I made of a strip of 4 mm stainless steel. Because the mast is not flat where I need to mount the stopper, I put a piece of cutting board between the backing plate and the mast. The idea is the cutting board will set to the shape of the mast and prevent point loads of the steel backing plate on the mast.
The stopper was installed using the 'copperwire' method I've shown above.
Erik Precourt mailed me he is working on a version of a bigger version of the Olivier Link for 8 mm lines, but this one it is not in production yet (pictures of the smaller links can be seen on http://www.precourt.ca/). Seems to me the perfect way to attach the shrouds. I'll splice them directly on the links. Clean, easy, light and probably very strong as the link will only pull on the mast from inside and not through bolts. Problem is: will the links be available fast enough? Else I will have to go with the plans, buy the wichard padeyes, make the backing plates and the epoxy pads etc.

The only thing to do is to weld in the mastfoot. More about that later on. I've got the welding machine at home, now I only need the skills to use it. So I'm already halfway there.

zaterdag 16 mei 2009

Floats ready

After filling some small spots I re-primed the whole floats. Then I sanded the primer back with wet-sanding (grit 120 and then 240 if I remember correctly), using the very old sanding machine below. This machine is my favourite machine. For the work on the boat/epoxy/filler it works much better than my two fancy and very expensive festool sanding machines.

I didn't work very hard on the inner side of the floats in between the beams, as no one will ever see those areas under the wingnets.
Below the floats have been painted with one coat. The next evening I painted a second coat.
Looking from really near it's easy to see the paint job is not a professional spay-job, but standing 1,5 meter afway it looks quite good in my opinion. The gloss is OK (see below), I guess it will even shine a bit more after putting on wax.


Below most hatches etc. have been bolted down. Don't underestimate the time it takes to install all fittings and hatches. There are a lot of bolts to fasten, and all rvs bolts in alu parts have to be insulated to prevent corrosion. I'm using a product named 'duralac', a sort of quick drying paint especially meant to insulate metals.
I didn't put non-skid on the bow and stern area of the floats, as I expect I won't be walking there. If necessary I can buy a pot of gray paint and extend the non-skid any time.





zaterdag 9 mei 2009

heavy metal

Me and my friend Eelco worked a bit on parts for the trailer.

End result of a few hours grinding, sawing and welding: two float supports, four adapted trailer supports for the angled support for the main hull and a mast support which will slide into the 45 degree angled winch tube of the trailer. Welding is a bit sloppy, I'm using a small arc-welding machine not very suitable for the thick steel. For the aluminium welding I can lend a big MIG-welding machine and I intend to do a lot of practice runs first before actually welding te parts, to make sure they will come out good looking and strong.