Sanding in Tight Spots

RANTAN, my Tony Dias–designed Harrier, was launched in 2008. She’s a glued-lap boat planked in plywood; her hull is round sided but with a flat bottom to easily take the ground and live on a trailer. Since her launching, she’s not had much maintenance thanks to a well-fitting cover and a secondary top winter cover. I’ve refinished the brightwork on her cherry seats, refinished the removable floorboards, and redone the orange paint on the rails once. This winter, while she didn’t need any wooding—none of the finish needed to be taken back to bare wood—she did need to be painted inside and out.

Photographs by the author

RANTAN (seen here at The Apprenticeshop in Rockland, Maine, where she was built) has lengthy decks in both ends that prevented me from reaching the stems. However, when I used the homemade extender, I could access every inch of the boat’s interior.

I set her up on benches 18″ high, which are 48″ long and 15″ wide. The height is great both for reaching the interior structure and working on the topsides of a small boat, and with RANTAN’s flat bottom I needed nothing in the way of props to keep her upright. The biggest problem was figuring out how to get to all the places that were easily reached during the boat’s build but are now tucked away. There are decks and benches that restrict access to the ends and sides, and the open gunwale structure has lots of small spaces between the tops of the ribs, the inwale, and the sheerstrake, all of which need to be sanded and painted but are difficult to access.

Possibly the best Christmas present ever: a portable tray that holds four rolls of sandpaper and four sanding blocks.

For sanding, my favorite tools are rolls of sticky-backed sandpaper coupled with soft hand blocks. Years ago, a friend gave me a portable tray with a bar that holds four rolls of sandpaper. Below the bar, the tray carries my sanding blocks and the scissors I need to cut the paper. The paper can be pulled off the roll straight onto a block; it can also be stuck to other tools suitable for tight spaces, and doubled back and stuck to itself for sanding small spots. Sandpaper rolls are expensive, but for an amateur like me, a roll could last an entire career of boat maintenance—after a decade or so of building and maintaining half a dozen small wooden boats, I’ve only had to replace the 80-grit roll (my boats are mostly painted workboats—80-grit is fine enough). I do use power sanders, but there are so many intricate spaces in RANTAN that most of the interior work is done by hand.

My overall plan for RANTAN’s repainting was to tackle the hardest parts first. I began with the challenge of sanding the inside of the sheerstrake. The spaces between the inwale and the sheerstrake are too narrow for sanding blocks to access, and I couldn’t get the pressure I needed with folded paper; there also seemed to be no way I could sand the small areas of planks beneath the ribs. I solved these problems by wrapping sticky-backed paper around a wooden paint stick and around a narrow 6″ length of 3⁄4″ × 6″ aluminum bar stock that I had in my scrap bin. With these I could access all the smallest nooks and crannies.

Narrow gaps, such as between RANTAN’s inwales and sheerstrakes, can be extremely difficult to get to for sanding, but with the help of some homemade tools, even the tightest of spaces become accessible.

Next, I moved my focus to the ends of the boat.

I lowered RANTAN from the benches and set her on the floor so that I could step aboard. Now, however, even when I lay on my chest or side in the boat, I couldn’t reach all the way under the foredeck or the sternsheets to sand, so I had to come up with a way to extend my reach. I had some 1 3⁄4″-wide hardwood battens with which I could make an oversized pincer tool that could hold a sanding block and (later) a paintbrush. I thought about cutting one of my sanding blocks down to a width of 1″ but then discovered some mini foam sanding blocks at the hardware store that were ideal for the job.

The tools for sanding in hard-to-reach places: the extender is homemade using a couple of battens, three bolts (two with wing nuts) and a mini foam sanding block; for accessing tight nooks and crannies, sticky-backed sandpaper can be wrapped around a paint stick or anything else thin, such as the short piece of aluminum stock seen here.

I rounded the ends of two battens, and drilled 1⁄4″ holes into them, equally spaced along their lengths—unsure of exactly where I would need them to produce the desired tensions, I drilled five holes. I then drilled same-diameter holes through the mini foam block—two, so that I would be able to adjust the angle of the block. In the squared end of the battens, I inserted a 1⁄4 × 20 bolt tightened down with a simple hex nut. In the middle hole I threaded a bolt with a wing nut (this would be used to adjust the tension of the pincers). Finally, I placed the sanding block between the two rounded ends of the battens, threaded a third bolt through both battens and the block, and tightened it down with a wing nut. And there it was, a 16″-long sanding-block extender that allowed me to reach into the very ends of the boat. I later used the same tool for painting by replacing the sanding block with a 1″ paintbrush into which I drilled a hole through the handle just above the metal ferrule (I also use this hole to hang my brush after use).

The job of prepping RANTAN for painting was time-consuming and not always comfortable, but with my simple and affordable tools I was able to reach into every spot on the boat.

Tools used for sanding RANTAN’s tight spots

Foam sanding blocks—standard and mini sized (I used a Gator Zip Micro Tool—1″ × 3 1⁄2″—which came with 80-, 120-, and 220-grit paper. I bought an extra pack of 120-grit paper)
Sticky-backed sandpaper in grits from 80 to 220
Paint sticks and aluminum stock bar
Bright rechargeable headlamp—essential when working in the ends of the boat
Battery-powered portable vacuum with crevice and dust-brush attachments (handier than a regular vacuum because it stayed with me in the boat and didn’t get in the way)
N95 face mask
Thin leather gloves (I use disposable nitrile gloves for painting)
Knee pads

Ben Fuller, curator emeritus of the Penobscot Marine Museum in Searsport, Maine, has been messing about in small boats for a very long time. He is owned by a dozen or more boats: kayaks, canoes, a skiff, a ducker, and a sail-and-oar boat.