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Tuesday, June 29, 2010

Cleaning the brush: A Chemical Engineer's perspective

This post appeared originally on Windborne In Puget Sound

Good varnishing brushes are definitely not cheap! The quickest way to ruin one is to let varnish dry in the brush - not something any of us wants to do.

But cleaning a brush is not an easy task. You may think that after triple-rinsing it in fresh paint thinner, the brush is clean. But put it away for a couple of days, and when you go to use it next, the bristles are  disappointingly stiff.

As a Chemical Engineer, I learned several things that have made brush cleaning a lot easier.  (What?  Practical knowledge?  Who knew?):
  • Use a counter-current wash system. This keeps the clean end of the system separate from the contaminated end. In a real chemical plant (for example, an alumina refinery) there would be as many as 10 stages or more. Here we will make it simple - we'll use only two.  Do it like this:


    • Save an empty paint thinner container. When you rinse out your brush, dump the now-contaminated solvent into this container. Soon you will have lots in there. As soon as you have enough, this is now your stage 1 rinse.  Squeeze out all the varnish you can from the brush, and then clean it thoroughly in the stage 1 rinse solution. Squeeze out all the stage 1 rinse, and wipe the brush on a rag, trying to absorb as much of the stage 1 rinse as possible. Dump the stage 1 rinse back into the stage 1 container.
    • Next, rinse the brush in 3 small changes of clean solvent. As above, drain all the now contaminated fresh solvent into the stage 1 rinse container, wiping the brush nearly dry between rinses.
    This works because even tho the stage 1 rinse is not pure solvent, it is not very far from it, as compared to the varnish itself. Then the pure solvent is only used to rinse out the stage 1 solvent - not raw varnish. There is a secondary effect: some of the varnish (and paint, and stain, and...) precipitates out in the stage 1 rinse container. When it does so, the stage 1 rinse liquid becomes less contaminated. By doing things this way, your use of fresh solvent will go down considerably, even while your brush gets cleaner.
  • Exclude one of the reactants, and a chemical reaction will stop.  Curing paint or varnish is a chemical reaction between the resins in the varnish and the oxygen in the air (and water vapor, if there are urethane resins involved).  Exclude air, and the reactions stop.  This is why varnish does not cure in the can.
  • Reaction rates roughly double with every 10° rise in temperature. For our purposes here, the converse is the more valuable: reactions rates are halved for every 10° drop in temperature.
Putting these things to work, on a day when I just need to preserve the brush for tomorrow, I give it a quick but thorough rinse in the stage 1 solvent, getting most of the varnish out of the brush, and then wipe it mostly dry on a rag.

Next, I tightly wrap the brush in aluminum foil - this excludes air and water vapor.

Finally, I store the brush on top of one of the holding plates in our freezer.

I really have no idea how long this process will preserve a brush, but I can set a lower limit.  I have pulled a brush out of the freezer (I forgot it was in there) after a month, and it was still pliable, ready to use.

Sunday, June 27, 2010

A floor for the locker

Please welcome new contributor s/v C'est la Vie!  In this project posting from June 12, 2010, Jeff shows us how he installed a floor in one of the cockpit lockers on C'est la Vie, improving stowage and protecting a pump at the same time:
With the paint dried and the wiring installed, we turned our focus back to the cockpit lockers.  We decided to leave the port side locker as is, but add a "floor" to the starboard side locker.  Below is an image of the locker...
The black hose on left attaches to our secondary, large capacity bilge pump.  The pump visible in the lower left of the frame is our primary, small capacity bilge pump.  The bilge on our Morgan is very inaccessible so placing the filter and pump mid-line in this hatch allows the filter to be cleaned and the pump to be serviced easily. Typically in this locker we place winch handles, snatch blocks, boom vang, etc. in milk crates.  The milk crates inevitably slide down an rest against the pump & filter.  Hence the desire for a floor.  In the image above I have already added nail strips along the forward bulkhead and the midships bulkhead (these are the white strips and made from seateak.)

Cardboard was used to create a template for the floor...
Once the fit was correct the cardboard template was transfered to 1/2 marine plywood and the  floor was rough cut.  I added a hatch in the center to provide access to the filter and the bilge pump.  Below are all the pieces of the assembly...
As of this evening the pieces were assembled and the non-visible side of the floor was finished with 3 coats of epoxy...
Since this project will not be exposed to sunlight/UV we simply used west epoxy with the fast cure hardener.  This allowed us to glue up the assembly and get a few coats of finish on in a matter of hours.  Most epoxy is not UV stable so projects or parts that will be exposed to consistent sunlight must be finished with an appropriate product (i.e. varnish or Bristol Finish).  Tomorrow we will complete this project by applying 3 to 4 coats of epoxy to the topside of the floor.
... and here is the completed project:
Looks really nice, doesn't it?

Friday, June 25, 2010

Pledge drive

I continue to be amazed with the attention this blog is gathering - thank you for making this the 6,862,142th most popular site on the entire Internet!

But I can't keep it going forever without your help.  There just aren't that many things on Eolian that are bloggable.  For this to work out for all of us, everybody needs to contribute - think of this as a pot luck dock party.

Come on now.  All of you have a small project of one kind or another that others would be interested in seeing. Contribute to the feast:
  • Write it up and send it to SmallBoatProjects at gmail dot com
- or -
  • If you have already written it up on a blog somewhere and are willing to share, tell me where in the wide world of the Internet to find it , and I'll come and get it.
- or -
  • Give me permission to "mine" your blog for projects. Anybody who is writing a blog about boating has numerous small projects buried in there. I'll ferret them out, if you let me. No, I won't put your content on here without your permission.
- or -
  • Send me what you have, and I'll do the write-up, with full credit going to you as your project, of course.

Every posting will feature a link to your article (if there is one) and a link to your blog (if you have one).  In addition, all contributors will permanently have a link in the "Contributors" box on the right side of the blog. This ought to drive some of the traffic that this site is seeing back to your site.  I will not take any recent posts (unless you tell me otherwise) - that way this site will not be in competition with yours. Instead, it will hopefully serve to "reactivate" some of your older posts.

But the most important benefit you'll get is the warm feeling of having helped someone thru a problem - one that you have solved. And we will all be the richer for it.

Pitch in!

Wednesday, June 23, 2010

The little Dutch boy could have used this...

Mike and Rebecca on s/v Katana have this up on their blog. This stuff looks like magic!  I know that there was at least one occasion on Eolian when having some of this onboard would have been a good thing (but that's a story for another time).
After hearing some strong recommendations for the product and watching the video below, we decided to invest in a medium-sized tub of Stay Afloat. The product, which is billed as an “Instant Water Leak Plug & Sealant,” is pretty cheap when compared to a sunk boat. We’ve had it onboard for a while this season and have yet to use it, which if definitely a good thing!



If anyone out there has any experience with this stuff, please post a comment!

Monday, June 21, 2010

Two birds, one stone

Where this reading lamp had been mounted, directly to the cabin wall, moisture from the failed window directly above had stained the vinyl headliner material.  The window had long since been replaced, but the stain remained.  I made a small teak plaque and mounted it over the stain, and then mounted the lite to it.  The end result?  The stain is no longer visible, and, the installation looks a lot classier.

Thursday, June 17, 2010

Vented loop vent

That sounds kind of recursive, doesn't it? Vented Loop Vent.

But given what it is that the vented loop on your heads is venting, it's probably a really good idea.  On Eolian, the original vented loop fittings were cast bronze, and were fitted with a tiny version of the joker valve on the vent fitting.  That is, the flaps of the duck bill would allow air to enter the top of the vented loop, but would prevent contents (or content vapors) from exiting.

In an Ideal World, that is.

But here in the real world, the occasional  puff, or drop would escape.  And you know, it doesn't take much.

So, I installed the smallest size thru hulls I could find at Doc Freeman's (a famous rabbit warren of a chandler here in Seattle, sadly now gone) into the insides of the bulwarks, and hooked up the vents to them with clear plastic tubing.

This truly is one of those very small projects that makes a big difference in the livability of your boat - especially if the head is near your berth.
 

Tuesday, June 15, 2010

Ventilation: Good

"Out of sight, out of mind" is a concept that may work well elsewhere, but on a boat, a long unopened storage compartment will develop mildew and odors. Chuck and Susan detail on their blog, Voyages of Sea Trek one solution to this problem:
If there is any one thing that people object to on a boat the most, it is unwanted smells. And as a boat gets older, it develops smells from all kinds of sources. There are volumes of information out there on holding tank and head odors so we did not plan to address them with this minor modification. After almost 20 years of living aboard, we have found that certain areas of the boat can develop odors from trapped moisture and condensation in any climate and any season. A bigger problem that can surface is mold and mildew, which can generate odors and also cause health problems in some individuals. We learned all of these lessons the hard way, and the solutions were actually quite simple.

The secret to keeping a boat odor and mold and mildew free is ventilation, ventilation and, of course, ventilation. Fans, air-conditioning and heating systems all help in the ventilation department. Other things like leaving hatches or ports open, even a crack, make a big difference, and fans and solar vents make huge improvements. But none of this will help much if there are compartments all over the boat that have no way to exchange air, and allow air to flow in and out. These enclosed compartments are further insulated by cushions and mattresses, not to mention latches that keep the access closed tight. Almost all boat builders want the interior surfaces to look as smooth and unbroken as possible, but once again, this contributes to the problem.

In our current boat, and the previous one that we cruised and lived aboard for 17 years, we took some time to open up all of the interior space to air circulation. Using a hole saw, we drilled ventilation holes inside the cabinets and lockers so the air can flow from one end of the boat to another. We use 12 volt computer fans strategically placed to assist the circulation process, since they are extremely quiet, use very little power and will run continuously for long periods of time. We also use a dehumidifier that runs all year long when we are plugged into the dockside power. It is incredible how much moisture it pulls out of the air, no matter what season and no matter whether we are running the air-conditioner or the heater.

The weekend was set aside to work on the circulation issues and make some improvements. The forward v-berth was a particularly problematic area. It seemed to always be damp, and since the anchor locker was forward of it and the shower just aft of it, this was a moist environment. The dehumidifier sits in this cabin and blows the treated, dry air up into the main salon from where it sits. But we knew we needed to get the area under the v-berth circulating air and with 5 inch cushions on top, this was only going to be accomplished by cutting vents in the side. The two berths in the aft cabin are the same with the added problem of water tanks under each berth. We store lots of items, including clothing, under these berths so it needs to be dry and odor free.

In the past, we have used a variety of vent grills. Our previous boat had an all teak interior just as this one does. So naturally we use teak grills for that finished look. But aside from the fact that these teak grills are way too expensive, in my opinion, need to be varnished and the slats are easily broken if something heavy inside the locker falls against them. We have had this happen on more than one occasion.We have used stainless steel grills and they work fine, but just don't look right to us. With the areas we wanted to cover done in a dark teak, we were concerned that anything white would stand out too much. So our options were black or brown, and square or round. The brown grills we could find were either too flimsy or designed to have an air-conditioning duct attached, and stuck out too far in the back. We found a nice, sturdy, black, round grill and ordered 6 of them to do the surfaces we wanted to vent.

The installation part was very simple. We used the appropriate size hole saw to drill through in the location we wanted the vent. We measured carefully to be sure it was centered where we wanted it, and took care that there was nothing behind the spot that could be damaged by the hole saw. When a hole saw is used on teak plywood, it is best to start the hole on one side and before it goes all the way through, finish drilling from the other side. This keeps the wood from splintering as the saw passes through the opposite side. Before we attached the grills, we took the time to sand the teak around the area the vent would be placed and put a coat of varnish on the wood. This way, once we start re-varnishing the interior, these areas will be done and we won't have to remove the grills again for a long time.




I wonder where they found those grills?

Saturday, June 12, 2010

Where am I?

This is not a project, so much as a product. But it is inexpensive and handy.

You have paper charts on board, covering the area you cruise.

And you have a GPS (well, most of you do). Often, that GPS is a chartplotter. So, those paper charts don't come out of the drawer too much, do they? You have them on board as a backup against the failure of the GPS, right? Are they current (probably not)? And have you checked the price of paper charts lately? Wow.

To get this straight right up front, I am not advocating abandoning the paper charts. They will work if the GPS dies, if you lose all electrical power on board, and even if the constellation of GPS satellites shuts down.

Another (I am a belt & suspenders kind of guy) navigation backup is available to you if you have an iPhone (and perhaps other smart phones too, but I haven't checked). For less than the price of a single paper chart, you can have all the charts for a huge region in the palm of your hand. The Navionics app for the iPhone cost me $9.99, and that price included all the charts for the West Coast of the US, Alaska (including the north slope) and Hawaii. 

These are excellent vector graphics charts, and include tides, currents, optional satellite overlays, and the ability to record tracks and store waypoints and routes.  Everything is on the iPhone (except the satellite overlays), so once you have downloaded the app, no internet connection is needed for use.

Where else are you going to get a chartplotter for $10?  And all the charts??

If you have an iPhone, you should have this one.  It really is a no brainer.

Thursday, June 10, 2010

Ventilation: Bad

Never thought you'd hear me say that?

When you are a liveaboard, and you live in Seattle, having your weather boards equipped with those ever-present teak slats is not a good thing - they let a lot of heat escape in the winter.

The Previous Owner addressed the problem by gluing a scrap of thin Plexiglas over the slats with (yes) silicone.  It was an ugly solution, but it did keep the heat in, and we had other priorities - it stayed like that for years.

Until, that is, the lower weather board (no slats - to the upper right in the picture) levitated itself in a seaway and dropped into the cabin.  Tho this did amazingly little damage to the cabin sole, it did break some joints in the weather board.  OK, so now there was a need to put the weather boards to the top of the list.

I repaired the broken joints with epoxy, and the loose joints in the larger, upper board as well.  I pulled off the Plexiglas, scraped off the silicone and removed the slats. 

The wood is 3/4" thick, so the plan was to use 1/4" on the inside and outside for flanges to trap 1/4" Plexiglas.  For safety, since pressure from a boarding sea will be from the outside, I decided that the solid flange should be on the inside.

I used a 1/4" rounding over bit in my router to make a finished edge on the inside of the opening.  And then a 1/4" rabbit bit to make a 1/2" deep 1/4" rabbit on the outside.  To make the outer molding, I used the 1/4" rounding over bit again on a teak scrap, and then sawed off the rounded edge, making a piece of 1/4" quarter round.  Bedding the Plexiglas in polysulphide, I installed the outer trim molding I had just made with small brass brads.

Six coats of polyurethane (what you see happening in the picture) finished the project.

Note: we have not made any changes to the weather board "stowage" (the boards just lay on a pad on the cabin top next to the sliding hatch) which caused this project to be bumped up in priority, so if anyone reading this has a good solution for storing weather boards under way, I really need to hear about it.  Add it as a comment, or submit it as a project, please.  Thanks.

Tuesday, June 8, 2010

Carbon fiber, tapered battens, and a slack leach

This project is a copy of an article originally published at Sail Delmarva, reprinted here with permission. This is not a large project, but it is a large post...
Before: different boat, but same model, same sails, identical problem.


I admit it; I'm cheap. And I enjoy fixing anything I can, to prove I can. If I have to fix it though re-design, that's even better, and if the repair method is unusual... better still. I'm a tinkerer.

The main sail leach on my boat had been falling off to leeward in a terrible way, as much in light winds as stronger stuff. No just an inch or so - a regular S-shape as much 12" to leeward. Another PDQ sailor mentioned that thicker battens had been installed in his main by a sail maker and had worked for him. Being cheap and willing to make a simple thing more complicated, I decided that tapering the battens by stiffening the back 60% with carbon fiber TOW (tension oriented weave or unidirectional fiber) would do the trick and not thicken them so much that they would not fit the pockets. After all, most beach cat battens are tapered. The draft of a sail is tapered - more in the front, and less as you move aft. And it was also a fix and improvement I could finish for the next weekend!
Batten stiffness is rated by the weight required to deflect a 40" sample by 4". The original battens were 3 pounds for the upper 2, and 4 pounds for the lower 2. The lamination changed this to 8 pounds on uppers and 10 pounds on the lowers, exactly what my back-of-the-envelope calculations using internet carbon stiffness values predicted. Unidirectional carbon works for this project because it is that it is not just stronger than glass, but also much stiffer. If you were to substitute glass it would take many layers and the battens would get too thick to fit the existing pockets. Unidirectional fiber is required; more of the fibers are oriented in the correct direction and they are not deflected into a serpentine path by the cross weave.The forward part of the batten remains nicely flexible. It seems so obvious; the battens on my Prindle were tapered, and in proportion to the PDQ, much stiffer at the leach that the stock PDQ battens.
A simple job, really, easily accomplished:
  • Sand the batten.
  • Cut the TOWs to size.
  • Laminate one layer of 1" wide by 11 oz. graphite to each side. Taper fibers to avoid a hard spot. I did this by ending the fibers about 6" differently on opposing sides.
  • Sand lightly and add a second coat of epoxy.
  • Sand lightly again, by hand, 220 grit or finer, to get any sharp spots.
  • Epoxy again. Optional; I didn't.
The carbon tow came from West Marine, though it is not in the catalog. Defender Marine has a 3" x 50' roll (http://www.defender.com/product.jsp?path=-1|10918|16458|309345&id=12428), though I think I bought a `15' roll, and that was just enough. I split the 3" roll to long 1" strips with sharp scissors - delicate because it tries to fall apart, but not difficult. There were no tricks to the laminating, other than starting at the leach end of each batten, adding resin to only about 1-foot of each batten and letting that soak while I added resin to the first 1-foot of the others, and then going back to the first to finish the full length. Doing it this way keeps the fiber in place, rather than having it creep as you brush the resin toward the luff end.

I am still going to re-cut the sail. I believe I need to remove ~ 3/16" out of 2 seams, 50-70% of the way up. The "after" photo shows some residual sag. But the stiffer battens were a huge help on the sag and treated some vertical wrinkles as well. I will be happy until fall.
An easy project for any boat with full length, un-tapered battens. Like so many engineering projects, it is invisible when well done... but I appreciate it whenever I look up, I found myself able to walk away from a couple of well-sailed 45-footers (all sail boats heading the same way are racing), and my pocketbook appreciates receiving a few more miles from a good sail. The speed difference is appreciable.

After: not perfect, but much better!

A typically thorough engineering treatment from Drew.

Sunday, June 6, 2010

Easy tasks get done

This project from s/v Estrellita 5.10b, May, 2010. Livia's key observation below: "...easy tasks get done and annoying tasks are easy to push off" is soooo true.
You guessed it. It's HAUL OUT MONDAY!

I can tell that you are excited.

Underneath our cockpit is our 29HP diesel engine, a Volvo MD2030D.
Volvo MD2030D


Our impeller is what moves sea water through our engine which passes around tubes of coolant and cools the coolant so it, in turn, can cool the engine. This is called a heat exchanger and works the same as your radiator in your car except your radiator uses air.

The impeller lives inside the raw water pump and should be checked regularly. The housing for it is not terrible to open but not exactly a "pre-sail" check. Plus, we generally would have to replace a paper gasket because it tears AND you have to shut off the sea water intake (raw water = sea water) so you don't flood your boat.
Raw water pump


The impeller itself looks like a black rubber asterisk. Ours had one blade torn in half and two others cracking. They can still move a fair amount of water when damaged but if they stop, you overheat and when they blow up into bits, those bits get into your heat exchanger and plug it and generally become a PITA. If you look closely you can see the torn blade (clicking on the photo might help if you want a larger size).
Cracked impeller and speed seal

What you can also see in the photo above is a new pump cover with an o-ring instead of a paper gasket. After inserting a new impeller (or after checking an old one) there are two guide screws that are left inside the pump.
Impeller and guide screws


After sliding the cover onto the guide screws and hand tightening those, you insert two other screws, also hand tightened with etched sides that make them easy to handle even when wet.

Speed seal


We can now check our impeller as easily as we can reach the raw water shut off...which is still a wee pain, but much, much less of a pain now. And if I have learned anything about maintenance it is that easy tasks get done and annoying tasks are easy to push off.

Now, complete honesty. We are right on time with all of our other engine maintenance, but we have *never* checked our impeller before this haul out. And, after reading the detailed log kept by the previous owner, I don't know if he ever checked it either. This would mean that the impeller inside was original, from 2004 and had 730 engine hours...and it was cracking...and the gasket was completely decomposed.
Taking Livia's observation to heart, we are going to fit out Eolian with one of these too. Side benefit: you get a new impeller cover plate. It is the cover plate and the bottom of the well in which the impeller sits which form the side seals that keep pumped fluid from sneaking from the high pressure side back to the low pressure side, lowering pump efficiency. A new one is a good thing.

The device is a SpeedSeal impeller cover - it can be gotten direct from SpeedSeal, if not from your local chandler.

Friday, June 4, 2010

For horses, for sailboats

Originally published on Windborne In Puget Sound

I stopped in at our local farm supply store and bought these two fittings for a total of $5. They are solid bronze, and I plan to use them on one of our flag halyards. I priced the same (OK, similar) fittings in the West Marine catalog...
Want to guess?
$9.49.
Each.
A lot of horse tackle is either stainless or bronze, and is priced without the "marine multiplier" - next time you are nearby, check out a farm supply store.

If it is springtime, there will even be real, honest to gosh peeps!

Wednesday, June 2, 2010

The KoolAid boat on the dock

Some of you may be old enough to remember the Kool Aid commercials featuring the "Kool Aid Mom on the Block," an idealized mother wearing an apron and high heels who always served Kool Aid, and therefore always had all the kids on her block at her house (was she NUTS?). Well, I fear that having posted this on their blog, Livia will have all the boats on her dock coming over, corroded brass in hand, looking for some Kool Aid. (I'm pretty sure Livia will skip the apron and high heels)
Two years ago, about a year after the purchase of our boat I decided to finally tackle our seriously gross cabin lights. This is a medium tarnished one, light fixtures near water sources (galley, head) were worse.

Before

We polished a few by hand with Bright Boy and with Nevr-Dull both of which worked but were very labor intensive. I came across a tip online to soak your brass overnight in Kool Aid. I bought Kool Aid packets - the kind you still have to add sugar to. Then I added water but not sugar.

Hand Dye


I soaked the first fixture for about 1.5 hours and it was a lot better. However, I soaked two more overnight (because I was running out of time) and the results were amazing.

After Kool Aid


The Kool Aid cut the elbow grease down to about 10% of what it took without.
After polishing


Anything with citric acid as the first ingredient probably has the same effect.

Brass is a high maintenance item if you want it to look good. It has been 2 years since the Kool Aid project and the fixtures are dull again. No pitting, no grossness, just dull. My thought is that the longest I can get away with doing them is every 2-3 years. If I do them in the next year, it will be a quick and easy job - not painful at anchor. If we wait longer it starts getting back to the big job it was the first time.

That, right there, is the balance we are trying to find. Do enough maintenance, often enough, that painful jobs are avoided when possible but not trying to stay ahead of the curve any more than that.

- Livia

Warning: The Kool Aid *will* dye your hands. Mine were green although they are only lightly green after a shower ;)
Be sure to visit s/v Estrellita 5.10b as their days count down to cutting the docklines.