dinsdag 29 juni 2010

Pulpit, furler, tiller-tamer

Yes, this is yet another go at the diy furler: mk3. The all plastic cage on my furler mk2 didn't work as well as my furler mk1, because the furling line had a tendency to slip on the drum. Feeding the line in and out via one big eye works much better (actually it works perfect). For the rest the fuler is the same as my Mk2. From this weekend on I'll be sailing with my family for hopefully about three weeks, after that I can probably tell if this furler works in all conditions or not.
From a distance the boat still looks quite good, in my humble opinion. Here we are anchored in knee-deep water.
Below my 'tiller tamer'. Simply release the shockcord from the camcleat to release the tamer. With the tamer tensioned, there is enough friction to keep the tiller in one position.
I originally planned to put bownets on my boat but after having a good look decided it's probably not worth the effort, as the nets will be very small.
One thing I however DO recommend to install is a pulpit. Originally I thought a pulpit would just be for show, but after having been forced to go to the foredeck a few times with a bit of wind and waves to sort out the jib I know better. It's very uncomfortable and (in my opinion even) dangerous working on the tiny foredeck without anything to hold on to.
I thought making the pulpit myself would be a nice opportunity to learn something about working with metal tubes and a good excuse to finally buy my own MIG welder. I bought a 200A inverter MIG welder. It's about the max I can run on domestic power (even had to put heavier fuses in the fusebox, as it would blow the normal fuses by just turning the welder on).
Step (1): make a mdf mold to make the big bend at the front of the pulpit (here I'm using two 18 mm pieces of MDF).
Step (2): probably not necessary: make recess in the two halves of the mold with a router, after that I glued/screwd the halves on top of eachother.
Step 3: bend by hand. This bend was around a mold with the radius the bend should have in the end. Not a good idea, as the tube has a lot of 'spring back'.
So..... I made a mold with a smaller radius, and did the final bending on that. On the first try I was not careful enough and extended the bend too much. Couldn't rectify that and had to start all over again with a new tube. With the below 'design' for bending it's however easy to carefully bend bit by bit - bend - check - bend - check etc. This worked well, but to bend like this (with a lever) it's necessary to first make a part of the bend by hand on a lager mold (as above) as it's only suitable to do the finishing bending.
Maybe it's because I'm not a metalworker, but the dwawings of the pulpit weren't very helpful to me. In the end it was easiest to just set the pulpit up with some scrap wood and some lines on the floor and measure & cut & grind till all the pieces more ore less fitted the drawings.
For the tube notching I found this tip helpful.
Because I had to do a lot of tube-cutting I had a good excuse to buy yet another tool: an Evolution Rage 3S mitre saw, which is supposed to be able to saw metal, wood and plastic with one blade. That sounded just perfect for me - one machine fits all. Big mistake. This machine itself is pretty lousy build but the worst part is the blades. They wear down very fast. I ruined one blade half way building the pulpit, and the other is already starting to get blunt. I know stainless steel is a pain to saw, but a few cuts in thin walled pipe shouldn't be too much to ask, now should it? In short: I should have known it sounded too good to be true and should have just bought some extra metal-blades for my table saw.
Welding the tube: put all settings of the welder as low as possible, and just spot weld round (starting with 4 welds: top, bottom, sides). This seems to be the only way to weld the thin walled tube without burning through.
Below end result, with welds roughly ground. Total cost material: 35 euro for 4 meter tubing (type 304, 20 mm diameter, 1,5 mm wall) and 10 euro for the ss plate to cut the baseplates from.

Ian Farrier recommends to first test-fit the pulpit before welding. That's not a bad idea. I first welded the frame of the pulpit, and after that test-fitted on the boat. It didn't fit perfect, and I had to make some adjustments before welding the aft base plates. The front base plates should be just in front of the front bulkhead, but in my case this didn't work out. I managed to drill two of the four holes of those baseplates IN the front bulkhead, aaaaargh. I'm not going to correct this: I will just fill those holes with epoxy and tap a thread into the epoxy.

maandag 10 mei 2010

diy furler mk2

The 50-miles race I joined with my brother didn't go too well for us. Right at the start the pin at bottom of my furler broke (I already had my doubts it would be strong enough, see earlier post). After sorting out the mess and hoisting the jib flying, we made good progress, overtaking a lot of monohulls. But halfway the race the attachment of the main halyard on the mainsail broke (what a shame, it was still on my to do list, but I thought it would hold as it had done so last few sails) and we left the race and sailed back using the jib only.

So it was no succes, but at least it was a good test for things to improve on the boat. Lesson learned: don't underestimate the forces on the rig, they are quite big even for such a small boat.

For other multihulls the race was a big succes. Against over 100 boats, line honours were taken by sorry alice (F31), second was Tom Siemerink with F32 Tresoor, third was Arno Molenaar with F31 Thrill Seeker. Fourth place was for the first monohull, a brand new 11,5 meter long carbon monohull skippered by withbread and Volvo Ocean Race skipper Roy Heiner. 5th place was for a dragonfly 970 and 7th place for a corsair 28.

After the failure of the first roller, I was ready to give up and to spend a few hundred euros on a commercial furler, but my brother convinced me it's good fun to try to build a proper working roller for a fraction of the cost. So I gave it another try. Below is the result. This time I made a cage for the furling drum enclosing the whole drum. Unlike with furler Mk1 it's not possible to feed a continuous line, but who cares? The furling line will just stay on the roller.

The roller MK1 had two big flaws.First the attachment points were not strong (enough). Beside that, the cage of the drum of the roller wasn't fixed in place. I mistakenly thought that made sense, but the result was the roller tended to roll instead of the sail. I fixed the cage by drilling through the main bolt and putting a pin into the hole.
The pin fits into a slot, cut in the cage, and locks it in place.
The attachment on top of the fuler is now made by a bent m6 (6mm) threaded rod, locked in place by two nyloc nuts in recesses (see photo below and above).
To fix the eye of the roller to the central bolt I made two threaded holes to put in short bolts. They are not bolted through (because that would weaken the bolt too much and it would snap again). The two stainless steel strips attach to the bow web pin, and will make sure the roller (+cage) can't twist.

maandag 26 april 2010

Still some things to post about

With the start of the new sailing season, I thought it was time to invest some money into proper equipment. Like these two high end fenders (thank you, kids). I'm not much of a salty dog armchair-sailor so these can remind me which is port (green) and starboard (red).
Also, I made a ring of tube (held in place with a bolted eyelet) on the end of my boat hook to be able to dock with a bit more ease (provided there is a pole on the dockside to grab with the ring).

Below is one of my high end fenders. I can use the loop of rope to drag it to the bow of the float. When not in use I can flip the fender to the inside side of the float. Having a fender at the bow of the boat is the only way to safely dock the boat moving forward.


I also made an extra support for the mast. The hole in the support (see first picture of this post) is to put the maststep-ball into, and locks the support in place. The black strap is double sided velcro. Very handy for tying ropes to the mast. You can buy it at marine stores for $$$$$ but you can also buy it at AV-companies for normal prices (about 2 dollars per meter).
I didn't bother to put a masthead on my mast - can't see the benefit. With a bare mastend it's easy to fix the (in europe) compulsery marking sign for 'long cargo'. The sign is held in place with a piece of 6 mm rod sticking through the mast and secured by two rings.

In the category things breaking: with one float unfolded the pads on the beams sometimes bind/jam a bit. I ground the edges of the pads already, but not enough. When I stamped on the beampad to put it in place, the epoxy glue snapped. Not sure if this happened because the surface wasn't prepared well enough before gluing, or because the epoxy is not flexible enough to handle this kind of peak pulling forces. I will clean and sand the gluing area, and then glue the pad again, using pu-kit-glue. This glue is superstrong but also a bit more flexible than epoxy and won't snap as easily.

We tested the diy roller furler (see earlier post), it seems to work ok. Watch for yourself.

video


This saturday me and my brother will join a 50-miles doublehanded sailrace. Just for fun. I only have the main and jib, and no lightwind sails so we will probably be smoked by at least the other 8 multihulls which will be in the race.

zondag 31 januari 2010

diy endless line furler (25 - 30 dollar)

For some time I have been toying with the idea to make a endless-line furler from standard automotive parts. Below is my fist try. It's made of an aluminium pulley (10 euro = 14 dollar), a standard skf double row ball bearing - type 3200 if I remember correctly - (10 euro), some stainless steel bolts and eyes and some plastic parts made of cutting board.

Since I have a backup forestay I can take some risks: even if the furler will fail nothing serious will happen.

The drum is a standard aluminium v-belt pulley (type Z). This pulley is 8 cm diameter. I would rather have a bit bigger pulley, but couldn't because my lathe is not big enough to handle bigger diameters.
I drilled 8 holes through the pulley (hope the photo shows the idea) to make sure the furling line won't slip. Big succes - the line locks in the pulley beyond my expectations.

Below the furler before assembly. From right to left: tang to mount the jib, cap made of cutting board to seal bearing, M10 bolt, bearing, the pulley with a recess for the bearing (made that with the lathe, of course), 3 rings to form a spacer, line-retaining drum made of cutting board (also on the lathe), piece of cutting board with an eye to feed the line, ring, nut with a hole and shakle.
I put the bearing in a liberal amount of grease, and sealed the bearing-recess with a plastic cap. I think this should be watertight enough.
The eye for feeding the furling line is held in place with a small recess in the furling drum (below).
Below a part I'm not too happy with yet: I used a 10 mm bolt to mount the shackle of the furler. Because it's threaded it's effecively less than 10 mm diameter, and with a 6,5 mm hole drilled through there is not much steel to hang on to. To fix this I drilled through the bolt and the nut, hoping this will be somewhat stronger. Added benefit: the nut is locked in place. I will probably replace this bolt by a unthreaded 10 mm rod.
Other part I'm not too happy with is the tang on the topside of the furler. there was not enough space above the bearing to just 'bolt through', soI fixed the tang with two short M6 bolts. Because the shape of the tang (wide, v-shaped), the forces on it will be quite high. I will probably think of another solution, but not before I have done some tests to see if the furler works.
Movie to show the furler: as you can see it can turn and swiffle in all directions, and it's not much work to put the line on the drum.(PS the movie is often down, I'm sorry)


video

dinsdag 12 januari 2010

Working on details

I added cleats in the center of the floats - will make tying up to a dock much easier.
Detail of my new halyard-routing. The halyards exit the mast about two meters above the deck, and run through two blocks, then to an organiser and then to the cockpit.
I found handling the jibsheets without winches too heavy with a bit more wind (even with 2:1 setup) and therefore added two winches. It's a shame in a way the boat gets cluttered more and more with stuff. My plan was to keep the rig very simple and to use as little as possible hardware.
Something I should have known: make sure there is a hole in the anchor locker hatch to run lines or chain through to the locker. I had to make this hole off center because there is a tab in the center of the anchor well to support the hatch.
I messed up most of the trampoline grommets because I didn't have the proper die set to fix the grommets, so I replaced them with a piece of webbing (sandwich webbing-trampoline-webbing).

Without the grommets the trampoline is not so 'bling' anymore, but I believe the webbing-loops will spread the loads much better thant the grommets. I didn't remove the grommets closest to the hull, because the lashings to those grommets have to be loosened every time you fold, and with the lashing throug a grommet that's easier than with a lashing through a webbing.
Detail: the webbing runs through the holes of the former grommets. The 'eye' of the webbing will be on the lower side of the trampoline.
Next project will be: making some sort of removable galley with a kerosene burner because next summer I will be sailing with my family for a few weeks and I want some cruising comforts by then. My plan is to make a sort of box which will stand on one half of one of the cabin-seats. Ideas are welcome....