Monday, June 5, 2017

The Sanding Arsenal

My Dad always said that "tools are half the job".  When it comes to sanding, that is for sure the truth.
If you use sandpaper that is too fine or a sander that is too small, it will take you forever to do a big job.

Efficient sanding usually involves starting with a coarse grit paper to remove the bulk of the material and then working toward finer grits to get rid of the deep scratches made by the coarse grits and leave you with a smoother finished surface.

Velcro, Softie Glue On, Hard Glue On, and Bolt On
 Here are the sanding pads we use on the 8" variable speed polisher/sander. 
Stick On (velcro) and Glue On Discs
The Velcro pad (yellow) is easy but the paper is expensive and not readily available.  The Glue On (white) is great for whatever sandpaper is locally available but 60 grit is usually coarsest available.  Sandpaper is stuck to the Glue On pads with 3M Spray Adhesive.  The Smoothie (blue) is a Glue On but is soft and normally used for surfboard finishing because it conforms better to curved surfaces.  

The last one is a Bolt On which is used with coarse resin impregnated discs for aggressive sanding.  It uses 7" hard discs that are available from the hardware stores here.  They are available in 20 and 36 grit.

Polisher, Mouse, and Dremel
The grinder on the left is an 8" cheap Chinese tool.  It is my 3rd one.  The first one died from lack of grease.  The 2nd one dies because water killed the electronic speed controller, and this 3rd one is a plain vanilla cheapest one available and has been the best.  Always disassemble and re-grease even a brand new Chinese angle polisher. 

The middle sander is a Black and Decker Mouse.  It is a vibrating sander and takes Velcro backed sandpaper which is not always available so I use 5" or 6" Velcro orbital sanding disks and trim them to size.

The last sander is a Dremel.  This is great for preparing and repairing gouges and cracks but not very useful for finish sanding.

Adapt SAE to Metric
When working in a metric country (most of the world), the spindle size is 14mm whereas the US size it 5/8-11.  If you need to buy a pad anywhere except the US, it probably won't fit.  That is why I bought this adapter on ebay.  Now I can use any attachment from anywhere in the world, on my 5/8 thread polisher.

Finally, hand sanding is how you want to finish most surfaces.  Foam blocks do a good job but if you are confined to small spaces, cutting up rubber squeegees may be the best bet.

Saturday, May 13, 2017

A job we never wanted to do.

Initial Sanding to the Yellow Primer
For almost the past 2 months we have been sanding the antifouling paint off the hulls.  It has been the most miserable and dirty job we have ever done.  The paint was thick and hard but we couldn't be too aggressive and sand through to the epoxy hull and damage it.  A yellow primer was used in Grenada and now, when we were sanding, that primer coat was our indication that we were almost through the paint.

Wet Sanding to the Yellow Primer

20 Grit Sanding Disc got dull way too quickly


The Tyvek Taliban
We went through a stack of Tyvek Suits, hundreds of sanding discs, and hundreds of sheets of sandpaper.  The dirt under the boat turned blue from the river of paint slurry that the drained off the hulls.

There was even Blue under the Yellow
Blue Slurry Sludge
Most of the hull was easily accessible and you could usually sit on something.  Down lower, you were sitting on boards on the ground but the worst position was sanding the very bottom.  The sander was usually overhead and the slurry was spraying off the disc at Booker and draining onto my head.  The face shield helped but would get so dirty, it was impossible to tell if I was approaching the yellow layer.
All Sanded and Ready for Paint

I remember applying every layer of antifouling paint over the past 10 years.  Over the past 2 months, I got to see every one of those layers again. 
Never again will I let the paint build up this thick.

Spray Painting the Epoxy Primer (Jotun 87)

Tuesday, May 9, 2017

Out of the House

Mike and Pom

We have been house sharing a nice 5 bedroom house with Mike from FYNE SPIRIT since last January.  Mike has finished his refit and is getting ready to cruise Thailand with his Thai girlfriend, Pom.

Pangkor Island Marina and Lumut.
Booker and I don't need an entire house for ourselves.  We spend our days at the boatyard and just need an air conditioned place to sleep.  So we have rented an apartment in Lumut.  There are at least 5 other cruisers also renting at the Lumut Valley Resort Condominiums. 

Lumut is a ferry port for Pangkor Island and located just outside the Lumut Navy Base.  There are only a handful of restaurants but lots of shops that sell tourist junk.

Royal Malaysian Naval Base, Lumut
View toward town. monkeys in trees below
For $225/month, we have a one bedroom apartment on the 11th floor with a view of the river to the north.  

From our deck, we can see the Navy base piers to our left and town is to our right.   

 Yesterday we watched monkeys jumping between the trees 30 feet below us.

The house was nice, but this is great.

Sunday, May 7, 2017

Wet & Wild Sanding

Most antifouling sanding is done with electric or air grinders.  This makes lots of toxic dust which is unhealthy to breathe and also gets deposited and tracked all over our boat and neighboring boats.  It also clogs the sandpaper rapidly.   

I have had good luck in the past with water sanding.  The water washes the paint off the sandpaper and keeps everything cooler so the paint doesn't melt and clump up.  In Mexico, I strapped the hose to the grinder head, made a fiberglass cover for it, and it worked well.  In Australia, Booker sprayed water on the sanding disc while I sanded.  The big problem when using water and an electric sander is the potential of getting shocked.  

Hutchinson Sander
To solve this problem, I bought a Hutchins 7544 Random Orbital Sander.  This is a pneumatic sander with water injection.  Once arranging for the use of an air compressor, we found out that 'Random Orbital" actually means "vibrating".  There is no "orbital" whatsoever.  It just didn't have the guts to sand thick antifouling even with 30 grit sandpaper.  So we need to find a plan "B".

Malaysia is a 240 volt country.  I can't use their electricity to run my power tools.  I have to use the onboard AC inverter.  This makes 110 volts from the boat's batteries and I have discovered that it acts surprisingly like an isolation transformer.  

The best way to explain this is that after doing it's work at the motor, the electricity only has one path to return to the battery, which is through the power cord.  Since there is no path to earth, it can't travel through your body and out your feet giving you a shock.  This is called a Floating Ground.   

***Please do not try this at home or tell my Mom.

Here we are doing the wet sanding.  Booker is doing the spraying and I am doing the sanding.  The green tint is from the sun shade cloth. 

Unfortunately the water sprays everywhere so we are wearing Tyvek suits and hoods.  It is about 100 degrees and we are always trying to work in the shade.

Saturday, May 6, 2017

Cheap Labor is Not So Cheap

I contracted with some guys in the boatyard here in Malaysia to remove the antifouling paint.  The daily rate for a worker is about $45. That may sound cheap but when the skills that we normally take for granted are not accompanying that labor, inefficiencies result.  

I can sand with 20 grit (very course) sandpaper on a grinding disc and stop at just about any layer of paint that I want.  An unskilled Malaysian will oversand and destroy the bottom of the boat with gouges when using 20 grit sandpaper so I have to give them 80 grit.  The sander with finer sandpaper takes 4-5 times longer and also uses up that much more sandpaper.  Our Malaysian worker was able to sand one and a half square meters per day.  At that rate, it would take 60 days to remove the antifouling paint at a cost of around $2700 plus sandpaper plus I would have to add my time to supervise.  Almost the same price as I was quoted in Australia for removal via abrasive blasting.

If you're doing anything more complicated than ditch digging, cheap labor may not be the way to go.

Monday, April 24, 2017

Autopsy of a failed thru-hull fitting

Overboard is to the left, hose connects on the right

A thru-hull is a fitting that is used to connect the outside of the boat to a hose on the inside.  They are usually used for water intake and overboard discharge (In and Out).  Bronze is used below the waterline because a failure there could be catastrophic.  Plastic is usually used above the waterline on fiberglass boats.  Tortuguita has 25 fittings above the waterline and 15 below.

In order to prepare the boat for gelcoat work, all the plastic thru-hulls were removed and will replaced with new ones when the work is done.  

I really didn't suspect there were any problems but had quite a surprise and can now explain some mystery water leaks.

This is a thru-hull that is for the forward shower drain pump.  Since we don't use these showers, we didn't notice any significant leaking.  However, when a wave would splash up, it was apparently leaking in through the crack and had been seeping into the boat.

By the yellowing of plastic, these were old cracks
On the other forward shower drain, I found a broken 'tail' under the hose clamp and a crack at the outer hull.  Privilege likes to hide things like thru-hulls in hidden compartments that require quite a bit of work to access.  Since I never needed to replace one of these hidden thru-hulls, I had no reason to dig into these false compartments.

Many of the failures are from over-tightening the big nut on the back.  This cracks the plastic at the outside edge.  This particular thru-hull was also cracked at the inside edge which is usually caused by vibration or pressure fatigue.

New supply of 25 TruDesign fittings
Cheap thru-hulls like the ones that were just removed are made of nylon.  My research led me to only 2 brands of decent replacements.  Forespar (US) makes a product out of a proprietary plastic called Marelon.  TruDesign (NZ) makes their thru-hulls out of fiberglass reinforced nylon.  In this part of the world, it made more sense to go with the New Zealand brand.

Besides having a boat that is not leaking, the really cool thing about this whole project is now I know of more secret compartments to store things.

Monday, April 17, 2017

The Workbench

The normal boatyard workbench, pallet style. (Australia 2014)
When working on a boat, it is important to have a table or the like where you can put  things that are being worked on.  In a boatyard, that usually consists of something scrounged like a pallet or boards and if you are lucky, maybe a sawhorse or two.

Marina Island is different.  People are here for years working on their boats, and we may be also.  After all, we made the investment to buy a car and we really do like it here in Malaysia.

If you happen to be carrying carpentry tools on the boat, it is easy to knock out a table or bench.  Our woodworking tools reached the end of their lives in Mexico and since the voltage here is 240 volts, anything that I buy will be all but worthless in the US.

I had the opportunity to buy a workbench from Andy on SPRUCE that was originally built by Jeff.  The price was a reasonable $90 US and it was even equipped with a vise.  In the end, I will end up selling it to someone else and recoup some of the cost.

Even rolling on wheels, it was a hard push
The really nice thing about the bench is that it has locked storage underneath.  Instead of chucking tools in the car at the end of the day, everything can be stored in the bench.

This thing is really heavy.  It has to weigh 250 pounds and is built from some type of local tropical hardwood.  A forklift would have been nice to move it from the shed area to Tortuguita but since there wasn't one, we examined all the options to move it about a hundred yards.  We found an engine hoist on wheels sitting around and commandeered it to do the heavy lifting.

Workbench, vise, all out of the sun and rain in our catamaran garage

Now we have a proper workshop under Tortuguita which is so much better than the rickety pallets that we have used in the past.

My only regret is that I can't keep it.  Sure would look nice at home in the US.