Thursday, May 23, 2013

We got the shaft

Out of the boat, that is.  It will not, however, be going back in -- it is corroded beyond repair.  That was our bad news for the day yesterday, after it took several of the guys a few hours to pull it out.  They had already given up on first removing the propeller, which is so badly frozen to the shaft that it won't budge.

The shaft is so badly damaged that the only reason I can see that it had not already snapped in two somewhere along the line is that, at 3" in diameter, it is massively oversized for this boat.  Several of the yard guys mentioned that the propeller nut is the largest they have ever seen, and they've seen a lot of boats.  Unfortunately, they also told me this is the worst shaft corrosion they've ever seen, too.

The shaft is stainless steel or some alloy very close to it.  While stainless normally does not rust or corrode the way mild steel does, it achieves this magic trick by maintaining a continuous layer of oxides on the outside surface.  Deprive it of oxygen and leave it in water, though, and it will be subject to a very insidious form of corrosion known as crevice corrosion.  That's what happened to our shaft, as the boat and shaft  sat motionless for months at a time.

These lines correspond to grooves in the cutless bearing.

At each end of the shaft tube is a "cutless bearing", which is a type of bearing that is supposed to be lubricated by flowing seawater.  The parts of the shaft that lay in these bearings had tell-tale lines of corrosion parallel to the lubricating channels in the bearings.  That was actually not the worst of it, and if that had been the only corrosion, it is possible that a small amount of material might have been trimmed from those surfaces on a giant lathe to make the shaft smooth again.

No, the worst of the corrosion was in between these bearings, where the shaft sat in unmoving and thus oxygen-deprived salt water whenever the boat was not running.  Large patches of rust cover most of this area, and in and among these patches are pits that look just as if a worm had started to eat through the shaft. Some of these pits are as deep as 3/8" -- turning this part of the shaft smooth on a lathe would take it from 3" all the way down to 2.25".  While that's probably plenty of shaft diameter for this boat, the rest of the gear, from the cutless bearings to the transmission coupling to the propeller itself are all set up for a 3" shaft.

My Leatherman awl in a pit.  Thread-eye on the awl is 3/8" from tip.

Tip of awl resting on surface, for reference.

The yard has not yet quoted me on a new shaft, but a quick search on the Internet for 3" x 11' Aquamet or similar shafts tells me we are looking at something north of $7k, not including lapping the prop or any of the other work required to install a new shaft.  We had not counted on this and it's not in our yard budget, so we are back to the spreadsheets to see if we can still get all the work done that we need.  The shaft and prop will be sent to a specialty shop in Norfolk, where the new shaft will be fitted and the prop will be cleaned up and balanced.  We will also spring for a "Propsmith" tool, which will allow us to have the prop removed more easily anywhere in the world, at the additional expense of drilling and tapping holes in the prop for the tool to pull against.

The crew has also removed all the lead from the forward compartment, which is also the anchor locker.  As we suspected, it was unsecured and not particularly well fitted into the space.  I was relieved to find out there was a sump below the lead, so water accumulating in that compartment was not sitting in contact with the lead the whole time (though the lead was pretty thoroughly coated with rust).  The bad news was that there was over 100 gallons of water in there when we finally got down to it.  Also, it's a good five cubic feet or so of empty space that could, instead, have lead in it, which would move the weight much lower in the boat, and also leave us more room up top for the anchor chain, which has several times piled so high as to jam the windlass.

Speaking of anchor chain, we were also disappointed to find out that we only have about 350', not the 400' we thought we had.  Not a real big deal, but it does make a small difference in where and when we can anchor.  Adding chain is not an option, and buying a whole new, longer chain is not in the cards right now.  The good news here is that we think we can fairly easily add a pad-eye near the waterline for an anchor snubber, which will knock six feet off the depth part of the scope calculation.  Using such a pad-eye will actually allow 350' of chain to do the same job that 392' of chain would do without it in normal conditions.

As long as I am talking anchors, in my last post I mentioned that John gave us the storm anchor and rode he had bought for the boat, a very generous gesture.  John had told me there was really no way he could store the anchor on the boat, and so I hauled it up on deck to see if we could get it fitted for some chocks to hold it to the bulwarks on the foredeck, about the only place we figured we could put it.  It would not fit vertically, but we could mount it horizontally if we found the right hardware.

One enormous anchor.

While I was hunting around for chocks on the Internet I discovered that this anchor is actually designed to break down for convenient storage.  In fact, the manufacturer sells a fancy canvas bag for it that comes with the two wrenches needed to assemble and disassemble it, as well as a spare "clip," the part most likely to get lost.  I found the directions on line and immediately broke it down, making it much easier to stow below decks.  $150 sounded like a lot of money for a bag and a pair of wrenches to us, so Louise ordered a bag online intended for skis (about ten bucks, with shipping) and I'll pick up some cheap wrenches someplace to throw in there with the anchor (I already have the two required 3/4" wrenches, but it's nice to have a pair right there with the anchor for quicker assembly).  The assembly directions call out some additional parts, called "mud palms," that we don't seem to have, but they are not strictly required.

Much more compact when broken down for storage.

We met a very nice couple on a 40' Lagoon catamaran in the anchorage here Tuesday, while they were ashore in their tender walking their dog.  They are from the San Francisco Bay area, so we had lots to talk about, and after giving them a little tour of Vector we were invited for evening cocktails aboard their boat Ryana.  When the appointed time came, I simply could not start the motor on our fancy new tender, and we ended up taking the old tender, with its reliable Honda but no lights, which had us heading home before the last light faded.  We really enjoyed spending some time with Diana and Ryan and their dog Stanley, who left the very next morning.

I'm not sure why I couldn't start the Mercury on the new dinghy, but it took me the better part of an hour to get it going the next day, as well -- something I was insistent on doing before anyone showed up to buy the old tender.  I ultimately had to haul the battery charger down to the dock after so much cranking, but eventually I managed to get it to turn over.  Figuring it just really needed to be run hard for a while, something we did not do after getting it going Sunday, I then immediately took it out onto the Piankatank River to get it up to speed.

And speed it does.  I never managed to get to WOT -- I quit at about 27 knots (31 mph), and that was in relatively calm conditions.  I'm sure with a steely operator it could do 40 flat out, but I was not going to attempt that in an 11' boat -- too squirrelly.  This little shakedown cruise convinced me even further that we need a much smaller motor on this boat.  Shortly after I returned, a nice couple came to look at the old tender, but ended up leaving with just the 15hp Honda motor.  I've got the tender and trailer re-listed sans motor, which is not generating nearly the same level of interest.

As for the 40hp Merc, it turns out one of the guys at the yard here has a 25 Merc and is looking for more horsepower.  We might be able to make a straight-across trade, with the bonus that he and one of his buddies in the yard would be available to do the swap.  I have my fingers crossed that it works out, as it will be the most convenient outcome.  I am told that his motor has been painted camo, though, which is more suited to duck hunting than a yacht tender. I am inclined to rattle-can it white to match Vector. Louise thinks the camo motor will simply become invisible, at least while we're anchored in the swamp.

Today we finally made it over to West Marine, which is, quite literally, the largest store in Deltaville.  We're still living on the boat, which has no air conditioning, and we wanted to try one of the 12v fans they sell there.  I also picked up a small grapnel-style anchor for the dinghy, and a new life ring to meet USCG regulations (our old life ring, which is perfectly serviceable, is only certified in Canada, not the US -- go figure).  Mostly, though, I wanted to see how complete their selection of electrical, plumbing, and deck hardware was, before I launch into the many projects on my list.  I'm trying to pre-order everything I need (West Marine, even when they have stuff, is not cheap), but there will inevitably be a missing Mark-I Framistat when I have something half way apart.

On our way back we stopped at the local hardware store, which is convenient (as opposed, say, to Home Depot, which is 30 miles from here) but did not seem to be particularly well-stocked.  Still, I am certain I will be in there any number of times for last-minute items.  The bulk of the items I will need for The Great Electrical Upgrade™ are already on their way here, and we got a half dozen boxes already yesterday.

Among the items that have arrived in the last few days are some of the new window blinds that Louise ordered.  We bought the exact same style we had on Odyssey, and they look and work great.  The boat had some very nice bamboo-type Roman shades when we got it, but Roman shades are a bad choice, particularly below decks, because they simply hang down too far in the fully open position.  On the below-decks port lights, they still covered more than half the glass area even when fully retracted.  By contrast, the double-cellular models we ordered collapse to just about an inch in height, allowing almost all the light in and also allowing us to keep the portlights open for ventilation.

Even upstairs, the new blinds are much lighter and brighter, and open up more of the window area when retracted.  Also, we now have a blind for the windows of the aft saloon doors, which was previously lacking and made for a bit of overexposure at the dock in the evening.  We are still waiting on the ones for the large side saloon windows, and I will try to post some photos when we have them all up.  I've got the ones for the pilothouse windshields, too, but I will need to come up with some kind of track for them before I hang them.

This weekend is a holiday, and the yard will be closed for three days.  I'll try to make some headway on projects, but I expect we will also be collapsing in a heap after a very busy week.  If we get lucky the weather may even get pleasant enough for a swim in the pool.


  1. Oh dear. The shaft corrosion is not something I would have expected, although it makes sense as you explain it. Here's hoping you have no more unpleasant surprises.
    And I'm curious how I paid for 400 feet of chain and you only have 350 feet.
    So I can only say you no longer owe me a dinner, and the next one is on me, with very good wine.

    1. Just to be clear, John, I know you did not know about either of these issues. As regards the chain, I will get back to you after we actually measure it (when we paint new markings on it), so you can know how annoyed to be (if at all) with Dog River.

      When we spooled it all out on the ground here, I flaked it back and forth as much as possible, mostly to inspect it and let it dry out. Once it was out, the yard said it didn't look like 400', so I measured one of the "flakes" and then counted them, and came up with only ~325 or so. Then we counted the red marks, and could only find six, which would make 350' if they were spaced every 50'. That said, it's possible one of the marks is so badly faded we just can't find it, and/or my flake-counting method is off by a couple of feet per flake. Either mistake could account for another 50'.

      I'm not entirely sure how we are going to measure for the new marks, but first we are going to switch the ends so that the old bitter end is now attached to the anchor and vice-versa.

  2. To bad about that shaft being in such bad condition, but it sounds like your other projects are starting to fall into place. We will sit here on the starboard side of BessyBus and toast to your successes. Steve

  3. If there was anyway to get that shaft to Republic Diesel in Louisville KY, they could press the prop off and repair that shaft and repair the prop and rebalance it. They would grind out the pits and build it back up with SS weld then turn it back down to the correct size.They have repaired shafts for us as big as six in by 22 foot for us.

    1. The shaft is probably beyond repair. Even a competent shaft repair outfit would likely spend more money fixing this one than a new one costs; you'd have to start with a metallurgical analysis to determine exactly what alloy it is so the welds could match exactly. Next you would have to grind out every pit. There are not dozens -- there are hundreds or maybe even thousands of them. Then you'd have to weld each and every one. Then you'd have to grind each one down before turning the entire shaft on a lathe for the entire length. Lastly you'd have to X-ray every inch of the shaft to make sure each weld is perfect.

      My take on this is similar to that of, say, running re-treads on the steer axle of the bus. Our lives will very literally depend on this propeller shaft -- it's the only one we have, and if it breaks in the middle of the Pacific Ocean in rough weather we can lose the boat, and have to roll the dice in a tiny inflatable life raft, hoping there is a ship within a couple hundred miles.

      I will reserve final judgment until I see what the shaft shop has to say when they get it, but my guess is that the yard's assessment that it is headed for the scrap pile is accurate.

  4. Another tip... West Marine has a price match policy. If you go to a web site and print off the page showing the item as in stock at a cheaper price, they'll match it. Only way I can afford anything there. :)

    1. Thanks for chiming in -- that's a good point, and probably good for our readers to know.

      That said, one of the myriad problems with West's price match policy is that it only works brand-for-brand. Since West has managed to re-brand many commodity products with it's own label, they won't match them. For example, "Seachoice" is a brand of commodity products found in many retail stores and online outlets that is more or less identical to many WM-branded products, but you can't go in to WM, point at, say, a WM anchor shackle, and then show them that you can get a Seachoice one for 80% -- they won't match it.

      One of my dirty little secrets is that I am generally brand-agnostic, with only minor exceptions. So for example, I don't see a good reason to buy Blue Sea hydraulic breakers when I know that Airpax breakers are just as good. I can usually find Airpax or Carling hydraulic breakers at discounters and surplus sellers on eBay for half or even less than Blue Sea prices. But if I need a hydraulic breaker on short notice and go into West, Blue Sea will be my only option. Again, price matching will not apply.

      Lastly, while I have not experienced this myself, the Internet forums are rife with tales of WM managers finding ways to weasel out of price matching. (I have also heard that this has improved, I think by pressure from HQ.) So I will use it as a tool, but I try not to count on it.

  5. So did you miss the shaft corrosion on survey? I thought mine looked good when we hauled last spring but maybe we just didn't look hard enough.

    1. No way to see it without pulling the shaft out of the boat, not something that is commonly done on a pre-purchase survey. Remember, we have no struts -- the shaft is completely enclosed in a steel tube. All the corrosion mentioned above was inside the tube, between the two cutless bearings.

      Defevers have far less "concealed" shaft -- pretty much just the part in the shaft log and the cutless bearings themselves. By contrast, on my boat only about 18" of the shaft is visible, out of a total length of nearly 11 feet. Also, on your boat, there's less opportunity for stagnant water to sit against the shaft like this.

      You probably have nothing to worry about. If you wanted to inspect, though, you'd only have to move the shafts back a couple of feet, not pull them all the way out of the boat as we did.

  6. You might check out the shaft used in a water lube turbine pump. This is like one used in a well for a city well. The shaft is 10 ft long and can be make longer. they have a chrome sleeve where the bearing runs. also they run at 1800 rpm (+/_). they last for yrs. running in water. You could use a smaller size and have the chrome sleeve sized to 3". I know
    this is a lower cost way than you have talked about.

    1. Thanks, Charlie.

      These are completely different applications -- conventional stainless is a bad choice for salt water. Also, a well pump seldom sits idle; even if it does not run continuously, it runs at least daily -- the opportunity for crevice corrosion to develop is minimal. By contrast, a propeller shaft sits idle more than it turns, sometimes for days, weeks, or even months at a time.

      Trying to fit a smaller shaft would also be more expensive than just replacing with one of the same size, For starters, the propeller itself would need to be changed; I haven't priced a 32" nibral wheel, but I am guessing it's close to what the shaft is going to cost.

      As I said earlier, our very lives will depend on this single component. It's probably not the right place in the project to be trying to reinvent the wheel to save maybe a couple thousand bucks, which is all you might be able to save. When all is said and done, the cost of a prop shaft is less about the difference between, say, Aquamet and stainless, and more about the equipment and labor involved to machine the proper taper and threads on the ends, true it, fit the prop, etc.

  7. It sounds as if you're going to do the Great Electrical Upgrade yourself. True? By the way...why is this necessary? Just wondering.

    1. Yes, I am doing all my own electrical work. The same is true for plumbing, electronics, HVAC, and many other parts of the project. We just could not afford this boat if I had to pay yard rates for that kind of work.

      What we are having the yard do are the things for which I lack either the tools or the skills. I can't weld, I can't cut holes through 1/4" steel plate, I can't spray paint (especially in confined spaces), and I can't remove or install shafts and bearings. I'll admit I probably could have removed all two tons or so of lead pigs from the chain locker, but that, too, seemed like a job for younger men than I.

      As to "necessary," that's a trick question -- the last two owners used the boat just the way it was, so really nothing we are doing is necessary in the strictest sense. That said, yes, it is required for us to be able to use the boat as we envision.

      I will post more details as we get into the project, but the short version is that I could get neither an alternator nor an inverter/charger large enough for our needs in 12v. The existing inverter and alternator are working "OK," but the charger is so noisy that the VHF hums, and the inverter is so dirty that we can't run the microwave, induction hob, or electric blanket without fear of destroying them, and air conditioning is out of the question.

      Running the generator every time we want to cook or even warm up our coffee, while probably cheaper in the short term than upgrading the electrical system, is not really how we want to live. If we used the boat only occasionally, we'd just live with this limitation, but these are tasks we perform every single day of the year.


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