Boat Renovation: Cleaning Teak

Cleaning teak is the next step in re-doing our boat’s interior. To see the irst two articles — including the before pictures — see:

• Our Boat Renovation Begins
• Boat Renovation: Choosing Teak Cleaner and Finish

The Project Challenges

Our boat has a fair amount of interior teak — one large wall plus lots of trim — and it was horribly dark with years of teak oil. In some places, it was black with mold. And then there were the light spots where previous owners had pictures and hadn’t oiled underneath. The first step in refinishing it was to clean it thoroughly both to get rid of any mold and to make it a uniform color.

Cleaning with Teak Guard

I am using Teak Guard Super Cleaner and Teak Guard Finish (link to company website – they also sponsor The Boat Galley podcast, click here for a special offer.). The directions here are specific to those products.

You’ll need:

• Blue painters tape — get several widths
• Drop cloths (I used large trash bags as being a better size than large drop cloths)
• Foam brushes — I used 1 inch and 1-1/2 inch sizes the most. I re-used them from day to day but they do disintegrate after a few days. So get a pack of 25 or so
• Small scrub brush
• Smaller brush for crevices (this 3-pack will give you three good sizes)
• Small cup to hold cleaner — plastic is best
• 3 to 5-quart bucket for water — don’t use something that you’ll later use for food
• 60 and 80 grit wet/dry sandpaper. You may want 120 grit for areas with thin veneer. I primarily used 3M Pro Grade Precision. It’s purple colored and if you look really hard on the back of the package it says you can use it wet or dry.
• Sanding block — you could just sand with one of these but they’re expensive and generate a lot of trash. I bought a couple and wrapped the sandpaper around them.
• Rags
• Water
• If your teak was finished previously, you’ll need to send it. You’ll need a whisk broom with dustpan at the very least. A vacuum cleaner is also a huge help in cleaning up.

For large areas, an electric random orbital sander with wet/dry sandpaper (this DeWalt one is mine) is also useful. In that case, you’ll also want appropriate sanding disks (wet/dry) and a good vacuum cleaner.

How I Did It

My technique for cleaning the teak is a little different from the instructions the company gave. This is simply because my teak was so filthy. They say to spray the teak cleaner on; I used a foam brush to really soak the teak with it. Also, since I was working inside on much of it, I couldn’t simply run a hose over it to rinse but had to use rags and wipe it off.

It’s important to note that cleaned teak should have the first coat of finish put on it within 24 hours of cleaning. Otherwise, the natural oils in the teak will rise to the surface and the finish will not adhere as well, plus mold can start to regrow. You can apply the finish as soon as the teak is dry; I always did it the next day. Don’t clean more teak than you can apply finish to the next day — and if you’re working outside, watch weather reports. Next week’s installment will discuss applying the finish.

Pro tip on cleaning: have patience. Don’t try to work too fast or do too large a section at one time. Give the cleaner enough time to work and don’t get overly aggressive with scrubbing or sanding.

Different Methods

I had five different “categories” of teak to clean:

• teak that had to be left in place
• teak that could be removed
• teak that was previously varnished
• teak wall
• teak that was horribly stained with used motor oil

Teak Left in Place and Basic Cleaning Technique

If teak has any sort of a finish on it beyond oil — varnish, Cetol, Semco or wax — you must remove it before cleaning. See section below on my previously varnished teak.

Start by masking off teak, using blue painter’s tape and drop cloths as necessary. The cleaner will not harm gelcoat or Formica — but it will clean it! If you’re using it on exterior teak — say a toe rail — the folks at TeakGuard say to wax the area thoroughly to avoid clean streaks.

Pour about a half-inch of Super Cleaner in a small cup and use a foam brush to apply to a small section of teak. Let sit 3 to 5 minutes. Apply a second coat of cleaner.

Put a few inches of water in the bucket. Wet one of the brushes and scrub teak. Brown gunk will start coming off and collecting in the brush — keep rinsing it out by swishing in the bucket of water. That brown gunk is the old teak oil and dirt. Use a wet rag to rinse off the teak; keep scrubbing and rinsing until rinse rag isn’t picking much up. Then move on to the next section.

Alternate method if badly stained: apply cleaner with foam brush as above. Instead of using a brush, wrap a quarter-sheet of wet/dry sandpaper around a sanding block and dunk in water to wet (try 80 grit first, if necessary go to the coarser 60 grit). Sand area where the teak cleaner is; you don’t want to sand much of the wood away but you need to get the teak oil out. As sandpaper clogs with brown gunk, dunk it in water and use a brush to remove gunk. Rinse with a rag as described above.

Super Cleaner is non-toxic, so it’s safe to use where it may get into the water; treat your rinse water as you do any gray water on the boat.

Let teak dry. I leave it masked off for finishing the next day unless the tape has dislodged with my cleaning.

Teak Pieces That Could Be Removed

Much of our teak had to be removed anyway for reupholstering the settee and it was much easier to clean by taking the pieces out to the cockpit. I could get at the whole piece, sit and stand more comfortably, didn’t have to worry about surrounding upholstery and could rinse with as much water as I wanted.

We removed doors and many trim pieces. Even though it’s a bit of a pain to remove and then replace teak, it does make the overall job easier and I think both cleans and seals the wood better.

The basic technique was the same: brush on the Super Cleaner, wet sand it, rinse and repeat until very little brown gunk was coming off. These pieces were all horribly dirty, so I didn’t just use the scrub brush on any. Let dry.

Varnished Teak

The teak in the head (bathroom) had been varnished to make it more “waterproof” as had all the floorboards. I sanded it all off, using the sandpaper dry.

For the doors and floorboards, I used an electric orbital sander. I was initially afraid to use 60 grit as I knew the wood was a veneer, but discovered that the varnish was tougher than I realized. I was still pretty careful and set the sander to a slow speed where I had more control.

For the trim pieces that I couldn’t remove, I masked off the surrounding area with a double layer of blue tape and put drop cloths where I thought the sanding dust would fall. I did a combination of hand sanding and using a Dremel sanding wheel. Beware: sanding dust will go all over the place. You’ll find it in places you never expected. A good vacuum will help the cleanup.

Once it was down t0 bare teak, I brushed it with Super Cleaner and, for the doors and trim, went over it with a scrub brush and rinsed. These pieces were not badly stained under the varnish and so cleaning them was simple.

The varnish on the floorboards had blistered and peeled in some places, so I had to clean those areas more thoroughly, using the wet sandpaper with the Super Cleaner.

Again, I rinsed everything thoroughly and left it to dry overnight.

Teak Wall

Barefoot Gal has one large “showpiece” teak wall and a couple of sections of teak wall near the companionway. The ones near the companionway were very dark but cleaned up easily using the Super Cleaner and hand wet sanding.

The showpiece wall honestly scared me and it was the last piece I did. I knew it was the first thing you saw when you walked in Barefoot Gal. It was in horrible shape, with light and dark sections where pictures had and hadn’t been, plus there were about 30 screw holes left when those pictures had been removed.

I also knew it was a thin veneer and while I knew I was going to have to sand it to even the color out, I was scared of sanding through the veneer.

Again, I brushed copious quantities of Super Cleaner on and let it sit, then brushed more on, doing a small section at a time. I started by hand sanding the finicky bits, then collected all my courage and got out the electric sander with 120 grit wet/dry paper (used wet) and at very slow speed with a light touch. It worked!

Here’s the wall partly done — I still did a little more on the “done” side to totally even the tone out:

Teak Counter Stained with Motor Oil

I had no idea if I’d be able to get the used motor oil out of what should have been a gorgeous teak counter, but I was determined to do the best I could.

My goal was to get the motor oil out but not make that section of teak noticeably lighter than the rest of the counter. As always, I started by masking things off with blue tape and drop cloths.

Then I brushed on the Super Cleaner and let it sit, brushed on more and wet sanded then rinsed. It took 6 cleanings/sandings if I counted correctly. I did all the sanding by hand. If I were to encounter a situation like this again, I’d use the electric sander with finer grit sandpaper, slow speed and a gentle touch.

This counter and the backsplash and tiny shelf behind it took five days to fully clean, so when it was all “done” I did one final quick clean over it all, using the Super Cleaner and a scrub brush, to get any oil that had risen to the surface while I’d worked on other sections. Then I rinsed and let it dry overnight.

Next week: finishing the teak 

Related Posts

• Boat Renovation: Choosing Teak Cleaner and Finish
• Easy Way to Clean Teak Boat Decks
• Our Boat Renovation Begins

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