All fair now

Yea, it took a couple of months to modify the daggerboard because there really wasn’t a deadline and we worked on it only when convenient. Here’s the end of the fairing process, almost ready for primer.img_0277

and finally into Interlux Perfection paint…

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Keith, I’m quite happy with the final shape:

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Final step will be to measure for the standing waterline inside the dagger trunk, and paint the bottom 1.5′ or so of this board with the same bottom paint (Petit Trinidad) the hulls got in November.

Well since we can’t go sailing, we keep our eyes open for other water fun.  Last week Colin led us on a hike along Yosemite Creek, originating about 8 miles north of the valley. It was pretty great to experience the creek growing with every little stream tributary feeding in. img_0336

After three hours of hiking we saw the acceleration towards the falls…

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Then you get to the cliffs’ edge, and hang on tightly to the railings. We had lunch with this Raven, and I was trying to get a photo of it taking off, still working on the elusive just-right artwork of “Ravenswing” to paint on the float bows of the boat. img_0319

And over the water goes, dropping 2,400′ to the valley floor. Griffin had never seen Yosemite Valley – getting their from the top down was an amazing experience – highly recommended!

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Visiting the park during waterfall season is magical. If you’re in to water. :)

Next up on Ravenswing is touch-up painting around the new starboard side port lights (windows) – recall that repair from a few months back had to be suspended because the weather at the marina has been too cold for the LPU paint to ‘kick off’ and turn glossy.

And a big hurrah! to Arlene and Glenn for sailing their Lagoon400 cat Wahoo from the Caribbean to her new home on the Chesapeake. Sounds like they had a great 1,300 mile run northbound. Hopefully they’ll let us raft up at their swanky looking dock (nice house!!!) You can check out their adventures here:

https://wahoosailing.wordpress.com

 

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Bogged down

For my son, master of word-play…

Ravenswing’s daggerboard is almost ready to paint. We’re being rather methodical and not-rushed about the fairing work. (Because the mast is still months away).

To finish shaping the board, we needed to add back the 1″ wide knife-edge taper to the trailing side. It was done in solid fiberglass on one side, a bit of thick putty in the middle, and another glass strip for the other side.

Then as the Aussies say, we coated the whole board in fairing bog. That’s epoxy mixed with the red micro balloons, mixed up like a very runny peanut butter and spread on as evenly as possible.

Also note the 4mm thick wood strips added to both sides of the portion of the board that stays in the trunk while underway. This finishes the ‘solve’ to the board having been too loose in the trunk case while sailing. (Geoff, I didn’t use plastic because this wood was sitting right in the garage and was easier to rip to the exact thickness needed)

Here’s the fairing bog after the first session with the long-board sanding paper. This nasty task brought back bad memories of the long-boarding purgatory from hull fairing a few years ago. Builders, are your arms burning yet, just reading this?

The dark spots are the too-low points, ie the sanding board isn’t hitting there to turn the red bog to the dull pink. We sanded further, looking for that fair-surface balance. You don’t want to go too far, though, and destroy the intended overall shape. getting better with a second fill and sand pass, but you can see we went too thin with the bog for a long section about 4″ in from the trailing edge.

There was another pass done after this photo, and by the weekend we should be able to show you the finished fairing work.

Update on the little 4hp Johnson: took the carb apart a second time and cleaned even deeper, but it still ran funky. Punt. It’s with Outboard Bill in Sausalito. I authorized two hours of search and rescue…

So when your wife gets you a shiny new pickup and you scrape together some dough to get it lifted up and accessorized, you DON’T expect the 4×4 shop to call with “well Mr. Carter, we had an incident on Saturday…”they got the suspension upgrade done and winch bumper mounted, then backed it into a partially rolled shop door. Geez. At the body shop now.

More reasons the daggerboard is taking too long: excellent rolling distractions. Who wouldn’t want to try out a genuine 60’s dune buggy on the Plumas County dirt track?!and while we’re in the north Sierra, hit some excellent single track on the new Hightower LT. holy cow, this bike is a bad ass! If any of you Ravenswing fans want to do some mountain biking when we’re not sailing, just holler. They’re lined up in the garage :)

Thanks Mom for road tripping to the Sierras with your kid. That was fun.

Ok, we’ll get a bunch of boat painting chores done this upcoming supposedly hot weekend. Literally watching paint dry!

Found our shape

You were probably wondering why it’s taking so long to reshape that daggerboard. Truth is, we split just after the last blog post. A great vacation trip to UT and CO. Once back home and the trailer cleaned up for the next adventure, we got out the shaping tools. Mom, the red stuff is the fairing compound applied directly to the foam core, getting the understructure shape just right before the final outer skin of fiberglass is applied.

Keith should be happy with this new foil shape. We’ve gone from a 12:1 aspect ratio to about 9:1. And remember there’s still a final 1″ knife trailing edge to add back once we get more epoxy on hand.

Next up was wrapping the whole board again with 17oz double bias glass. you’d think we’d be old hands at this by now. Got all materials prepped in advance and decided to wet out the glass on a table in the shed. Well, the combo of a fast epoxy hardener and the big cloth being folded many times to fit the tiny table led to heat build up. As I draped the wet cloth over the board the epoxy started kicking off. There was some frantic pressing in place, then realization that some had to be cut away and (thankfully there was enough) new glass cloth added. And of course, because the project is quite large, our normal “stretchalon” vac bag wasn’t quite large enough. I used 4mil basic plastic taped into a bag but that stuff just doesn’t handle as well. Only saw this on the pump and today we found some air pocket lumps on the board that mean a bit of grinding and reglassing.

Ugh, guess we’re not to be called pro yet.

Seattle Geoff stopped by today as he’s curious about current examples of upwind foils (he’s building a high performance 37′ cat now) and I was embarrassed he saw my vac bagging flub. He was kind about it :)

It’s been a few months since we finished the portabote seats and transom makeover. Today it finally got wet, using the Petaluma River launch ramp that is two miles from the house. Carlos, that thing still leaks – I need to lift it up, get some dye in the water and search for the hole in one of those seams.

The 4hp Johnson hadn’t been run in three years, including the fact that our 2016 oak tree fall had sideswiped it. Couldn’t get it started the other day so we put on the bravery pants, watched some YouTube and tore into the carb.

I cleaned out nasty old varnished gas and bad particles. But there’s still something affecting the main jet (?) because today it wouldn’t rev up beyond about 1/2 throttle. If any of you know what I should try next, please holler. This is an early 90’s OMC 2 cyl, 4hp. It’s VERY clean, acquired by a nice old man who only used it in Donner Lake.

We “ordered” the new mast six months ago now. The anxiety level about the time delay is high. Spoke to the builder on Thursday and he’s finished the ones ahead of us. Now they are doing some maintenance on the 144-head braiding machine and reloading it with the right weight carbon filament for us. It will also be used to make a boom for a J-Class boat. That’s pretty incredible sounding and somehow ironic that our main mast is the same construction as another boat’s boom! The builder won’t bother giving me a target finish date at this point – we just need to stay on top of the progress.

Alright, you’ve read this far, so maybe you’ll be mildly interested in the Carters’ western road trip. It can’t always be 100% about sailing after all. Here’s the trusty co-pilot in her pickup truck

Once into Nevada we jumped on to America’s Loneliest Highway (US 50)

Went underground in Great Basin NP at Lehman Caves

Then had the young’uns with us in Moab for their spring break. Jeanne rented us two of these

It was Jeep Safari Week in Moab

We spent a Saturday afternoon on the CO river

Met up with our Sierra Buttes Trails Stewardship team for awesome mountain biking

Jeanne found her hiking legs again and we promised each other to do more of it! Doesn’t she look great?

After Moab the SBTS team went to a conference in Telluride, which was nice but at 10,000′ on a cold morning I somehow pushed the new truck into a throttle sensor fault mode, which devolved into this on I-70 a coupe days laterthat was late on a Friday, so Grand Junction Chrysler handed us a loaner car for the weekend and we explored the beautiful area

Got more riding in at Fruita’s “lunch loops”

And the truck turned out to be a 30 minute fix on Monday for some electronics minor recall thing. A few extra days in the American West and we found various decorations to make the new trailer more homey. It’s just missing a nice framed portrait of Ravenswing in there! Maybe once the new mast is stepped…

Dagger Bagger

Sometimes it’s possible to worry too much about these projects. Last time we wrote of not knowing a reasonable technique for bulking up the daggerboard shape. After some careful measuring, it needs 5/16″ at the most, and most of the add will be 1/4″ or less.

We dug around in leftover building materials for some 1/4″ divinycel 80 (5lb density) foam core that had been saved for anymore interior panel making. Fortunately for timely efficiency (hard to get this stuff quickly) there was just enough.

The little pile of scraps was all we had left of three 4×8′ sheets from 2015.

Next we made a fresh vacuum bag with the last of the Stretchelon plastic, but it wasn’t quite big enough. So for a first, tonight we’re trying standard 4mil plastic sheeting from the hardware store. For a simple, flat part like this it’s working fine.

Thanks again to whoever dreamed up laminating curved panels under vacuum pressure. So satisfying to watch it work. This extra foam core will be very well formed on to the board.

Along with running out of vac bag film, we’re out of the fabric breather that lets air flow inside the bag, and soaks up excess resin. A quick web search at lunch today turned up an airplane builder who uses paper towels! He said use four+ layers. It was soooooo much easier to keep in position tonight, and nearly free. We’ll let you know next time how it worked.

In that last shot notice the darker seams in between the pieces of tan foam. That’s epoxy being forced up, and that will make the shaping process more difficult. The tools need to move between the hard glue lines and softer foam without gouging. There’s the downside of using all the scraps instead of single full sheets. We’ll just have to be careful.

Sunday with a glue gun

We got back to the daggerboard reshaping this morning by digging out a bag of foam core scraps. This would take longer, piecing together odd bits. But it’s better than waiting days for a new shipment, and that stuff is expensive. So with the little tabletop bandsaw we got busy.

I’d forgotten that the 5lb density foam core is difficult to shape with sanders. For anyone else doing this, these abrasive wheels on an angle grinder so a nice job without leaving bad gouges. Easily found at Harbor Freight, etc.

Here after rough shaping.

Then we cut off the last trailing 1″, which will get rebuilt later with solid glass and putty so as to achieve a sharp knife-edge for smooth water exit.

After lunch we ran down to Napa Autoparts for some body filler. Since this will be buried under the fiberglass, we’re not worried about exposing bondo to the sea. And it has the huge benefit of hardening in 20 minutes. So the afternoon was spent flipping the board over, sanding one side while the other had its next skim coat hardening up. It took four passes to get where we’re happy this new core will give a fair fiberglass’s surface.

Ok, the tail end is ready; now we need a plan for bulking up the forward portions. Here’s how much it needs to grow:

Anyone have a clever idea of what to use for bulking up the board? Jeanne thinks craft-shop balsa that come in thin strips, adhered to flexible matting. Or we could rip very thin cedar strips on the table saw. I’ve heard of “core mat” but don’t know anything about it. Any good experience is most welcome.

Ah, the smell of cut cedar!

When we built the big daggerboard from the same cedar stock as the hulls, there were a couple of days where the workshop smelled like Christmas and the forest as every plane stroke during the board shaping released more cedar aroma. And then it all got sealed up with epoxy, glass and carbon, never to be seen or smelled again. Until today. It was major surgery, but at least it smelled great.

Recall the prior post where you saw how “high aspect” the foil shape was. Over 12:1, and that’s likely causing some stalling, and contributing to the howling noises when Ravenswing got up to speed. The experts agreed, it needs a more aggressive rounding shape up front and more severe taper. So we pulled out the original plans, did some tracing, resulting in some fattening and shortening fore/aft.

The board is a bit under 2-3/4″ at its widest. The exit slot at the bottom of the hull is 3-5/8″. So the new shape is going up to 3-1/3″ and 28-1/2 wide, for a 9:1 ratio. The last 11″ wide aft are too thick, so that has to go. The front 18″ or so are too narrow, so that area will be augmented over the existing shape.

Step 1, saw in to one’s well built, but poorly shaped big ass board.

Then we cut 1-1/4″ off the aft edge of the rectangular head of the board so it will fit in front of a new shock-absorbing heavy rubber insert we’ll add to the back edge inside the daggerboard trunk on the boat. Great idea from Keith!!!

Got the board level and plumb up on a makeshift table, ready for a new tail end. This feels like we’re building an airplane wing – fun.

Now we need to transfer the skinny pattern into wood and foam core. We had the off-cut from the shape-checking guide board to use in transferring the angle to the table saw. Note the light piece of wood against the saw fence is the same as what was on the dining table earlier.

So while the rest of you were out partying Friday night, we played with string and wood blocks in the tiny shed.

And in this final photo, see how the new shape will butt up against the rectangular head section. It’s those little sharp triangular areas on each side that sit on the exit slot block at the bottom of the boat when the board is deployed. This weekend we’ll fill in between these wood blocks with foam core and get this new tail shaped and ready for fiberglass. I have a feeling adding the right shape to the board on the front half will be much trickier than this aft-half job.

For those Farrier builders reading this, fear not, this surgery did not touch the super-strong area of the board (embedded hardwood insert and 6 layers of carbon uni the full length of the board). Thankfully the surgery started about 4″ aft of all that.

And while on the subject of good smelling wood, here’s a gratuitous shot of last weekend’s homework. This time the missus didn’t just hand over a photo, it was a whole how-to book of iron pipe projects. This is marital bliss – Jeanne gets to display her treasures and Greg gets to see all her treasures find a nice consolidated home. Win win, and the vacuum glides along like the shelves aren’t even there!

Boatyard punchlist

Ravenswing came to the Spaulding Boatworks yard for minor repairs to the deck and port float hull from the mast fall. We had a small list of “well, while we’re here…” things to do. 

First up was maintenance and installation adjustments for the engine. In retrospect we should have bought an extra-long (30”) shaft, to get the propeller lower in the water and avoid some of the cavitation we’re experiencing in waves. With some surgery we could lower the motor 2.5” in its mount box. 


Then we bought longer control cables to facilitate routing them up higher out of the way in the equipment room. Also changed the lower unit oil for the first time; it was in good shape after the break in period. 
The big task turned out to be a redo of the escape hatch. It had been installed with the hinges on the forward edge, but when it opened, the swing was deep through the water. Also, the hull recess didn’t properly match the metal hatch frame, and I had offset the hinges a bit to compensate. Which of course had led to some water getting past the seal at high speeds. So what we thought was to be a couple hours maybe for hinge adjust and reset turned into a job across four days. The hull flange had to be chopped 3/4” along the top and then that offcut bonded down on the bottom edge. Then the hull had to be rebated around the hinges for the new (proper) swing pattern. We think the hatch will just clear the water now when opening. 

Those pics show you the new black Petit Trinidad bottom paint. Gone is the snazzy white look,  but this proper bottom black looks pretty serious. And we paid the yard pros to do a real boot stripe this time. (Straight, unlike our amateur wavy job last year).

We’re tackling our daggerboard vibration / howl issues in two ways. First is stopping the slop when the board is down. The trunk is 88milimeters wide inside, except for the top and bottom three inches that had extra glass wrapped over from the deck (and hull bottom) into the trunk. The hull builder did that for strength, but not to the plans, and it made the opening only 81.5mm. I made the daggerboard head (via shims) just a hair under 81mm to fit the opening, allowing 6.5mm slop once the Board was down. So to compensate we ripped long 3mm clear fir shims to bond on each side inside the trunk. They got epoxied coated and painted on the workbench, then epoxy-putty bonded in. That was tricky; buttering the 5’ long pieces and carefully sliding them up into the trunk, not letting the putty hit until the placement was right. Four went on each side. Bottom paint still needs to be applied to these inside the case, up to the waterline. 

Part two will be some reshaping of the board, to be tackled when we take it back home after weighing the boat. 

Final finish paint to the deck repairs went on Saturday so we could launch today.  But a 9am call from the manager informed us that paint didn’t get warm enough and had glazed over dull. So they’re redoing it, hopefully for a Wednesday launch. Also meaning we still don’t have the boat’s weight for the mast builder. 

On Friday afternoon I helped the project manager attend to the 54-yr old hydraulic scale. Turned out to be a simple low-on-fluid problem. As the sun was setting we hatched our plan to check the calibration. Here was our victim. 

The data plate shows its curb weight at …6,970lbs. Crazy to think that little forklift weighs close to our 40’ x 28’ boat. Anyway, up it went

And the scale shows …

… a very accurate match to the tagged weight. Certainly good enough for our mast-build needs, and we’ll put this scale in the crane rigging on Wednesday. 

As much as we need fall rain, we’ve had enough to totally screw up this haul out trip so just another 36 hours sans rain would be great. 

Anybody wanting to go for a motorboat ride Wednesday, Sausalito to Richmond, get in touch.