Why Build Another Boat? How "Grinder" Happened.

I built "Bantam", Phil Bolger's low power, high efficiency trimaran in 2002, and my wife and I used it for 1,000 miles of cruising.

We sold "Bantam" September 28, 2008 to friends who trailered it to Cocoa Beach, Florida, where it is docked right outside their home. I had started a new boat in April, a modified Bolger Cabin Clam Skiff, and it was nearly finished, and there was no room in my brain, or in the yard, for both boats.

I Don't Really Know Why

I needed a project, and I thought I might build something small to get from Jacksonville, Florida to Washington D.C. via the Intracoastal. Just a quick something for semi-camping aboard that would move along pretty well if we needed to. I had the plans for the Cabin Clam Skiff,

which I got because the looks appealed to me, and there was a good review of a completed project in Greece that was published in MAIB.
I looked at Jim Michalek's "Dorado",

and liked the SkiffAmerica, and agreed with Adams on most of his design goals:
"1. Classic style ("head turning" appearance) 2. Modern leakproof construction (epoxy, taped seam) 3. Easily built using quality materials 4. Durable 5. Low maintenance 6. Affordable 7. Trailerable 8. Easily launched from trailer 9. Shoal Draft 10. Beachable 11. Planing hull 12. Efficient 13. Long Range 14. Good load carrying ability 15. Generous storage capacity 16. Sea kindly and safe hull design 17. Smooth riding 18. Great handling and maneuverability 19. Cruising for two or day trips for two families 20. Comfortable accommodations"

At the top of my personal list would be serenity. "Bantam" was very quiet, and the new boat should be too.

I wrote Phil Bolger and asked if I could modify the Clam Skiff for a little more width. I could not figure out a way to get the great live aboard capability of "Bantam" in the five foot beam of the Skiff. I loved the openness of the Bantam, and the combining of the wheel house and living quarters. The cuddy cabin of most small boats seems to me wasted space. Bolger stressed this thought in his Bantam design, and "liked the melding of the cuddy and cabin by the use of the full headroom glass cabin. The cockpit had shelter, the cuddy had a view, and both were twice the size they could have been if they'd been kept discreet."

With "Bantam" you could cruise in fine weather with nothing but the top to protect you from the sun, and in cooler or rainy weather, you could enclose the whole thing, and cruise in comfort with a 360 degree panorama.

Phil replied that he thought the Clam Skiff could use a little more boat in the water, since the photos he had seen of the Cabin Clam Skiff looked like the boat was down at the stern a little. He wished me luck, but had too much going on to help with plans.

The big problem was how two people could sleep comfortably, but yet have room to move , cook, get out of the cabin, etc. in the 5'x 8' space. We slept on the two 2' wide berths on Bantam, and liked it, but I could not figure out a way to do it on the skiff. Could my wife and I sleep on something the size of a standard single bed? Yes. How to get a single bed in a space so small, and still have room for a galley, a table and seats, a steering station, and have space left to get around?
The Bantam had cushions that we used for sitting and sleeping, and I had the cushion thought stuck in my head. Cushions would have to be stored on the Skiff, because unlike "Bantam" I would not be lowering the roof and securing the cabin area when we were not aboard. Here is a photo of "Bantam"s cabin settee/sleeping arrangement.

At some point in my Internet searches for a suitable mattress/cushion solution, I found that there are good inflatable camp mattresses, that inflate and deflate quickly on 12 volt power. Well. If I did not have to figure in how to cut, manage and store at least 16 square feet of 3" thick cushions, the thing looked possible.

Above is a the rough drawing I overlaid on Bolger's plans. I increased the beam 7 inches to 5'7", and added a motor mount extension to lengthen the boat to 19'6". Boarding, working on the engine, getting back on after a swim all get a lot easier if you have that platform, and the extra length would float the 40hp four stroke as a bonus, and watertight compartments float the stern in an emergency.

One thing we did not have in Bantam was a permanent table/seating spot. I ended up hanging a table from the rear step, and it worked very well, but was in the way unless you were moored, and didn't need to get around easily. The real starting point to the new cabin arrangement for the skiff would have to be the table.

Figuring It Out and Building

Bolger designed the Clam Skiff at the request of his friend "Dynamite" Payson. He wanted .."a solid skiff that could stand generous power, carry a big load, and have flat footing right out to the side. Nothing about it should be hard to explain."
Bolger later modified the design to have a small sitting height cabin with a sliding roof, and called it the "Cabin Clam Skiff".

I wanted standing head room, a little more cabin space, and a swim platform/motorboard. I liked that the hull was square sided, and I could make my cabin ends the bulkhead structural members. If I made the chines triangular, I could glass them, and have a very smooth interior.

Water that came aboard could drain right through limber holes on the sides of the bulkheads, through the cabin, and back to a bilge pump.
The boat is flat bottomed, with a little rocker at the bow. It has a huge 16" wide by 1 1/2" deep shoe, which Bolger said came from his experiments with "cutwaters". How will the hull perform? I don't know, but from what I've read, if you just slow down a flat bottom boat when the water is rough, you'll be ok. I want a canal cruiser that can jump up and run if the water is flat, and for some reason I want to get the fun over with in a hurry. I think the big shoe, and the 1" thick hull, will make pounding less of a bother, but...

Here's photo of the hull sides joined with " Payson Joints", and the bulkhead locating battens glued on. If you get to this stage, you pretty much have a boat.

The two cabin end/bulkhead are cut a little long, attached to the floor and stern and motorboard go in. All the fastening was done with sheet rock screws into the battens. After the epoxy set the screws were removed, holes filled and seams taped.


The hull sides are pulled together at the bow, and two layers of 1/2" A/C go on. Then the big shoe, and some trimming.

So far, so good. The basic hull of the skiff builds in a hurry.

The roof of "Bantam" had to be redone because the foam/thin ply/glass sandwich was too heavy. Very stiff, but too much weight. I tried to make the roof of the Cabin Skiff as light as I could, while still using wood, not fabric. I crowned it slightly to make it stiffer. It weighs 48 lbs. without the grab rails or paint, more like a kind of wood bimini. The edges slightly overlap the cabin on the sides, and extend 6'' in the stern, and 2' at the bow.

Making a Convertible

Here's a photo of the cabin top. Eighth inch Okume for the top, and half inch for the frame.

Converting a completely open boat with a roof, to a completely enclosed live aboard cabin cruiser takes some doing. You don't want to make the process take too much time or work, and the whole enclosure still needs to be lightweight.

My first thought was to have split doors like the Bantam, with the top part of the door removable, and the bottom part hinging down, and then to make very light 2' wide clear vinyl faced window panels to close the rest to the cabin. With that in mind, I made the battens for the roof 2' apart, so I could store all the cabin enclosure panels and doors out of the way, on the underside of the roof.
I did a trial fit of a couple mock panels, and did not like where the idea was going. So, I found a source for vinyl fabricating, and had windows and screens made. I'll attach them to the cabin uprights with a combination of "Common Sense" and "Lift the Dot" fasteners. The doors and rolled up windows and screens will store on the ceiling, and I saved a little weight. I'm hoping for less that 15 minutes to go from open boat to enclosed cabin. We'll see.

Mocking up the Cabin and Top

Here is the first mock up of the cabin. The top is held up by spruce posts 1 1/2" square. The uprights on the sides of the doors are laminates of 3/4 inch spruce and 3/4 inch rectangular aluminum pipe. They stop side to side movement of the top.

The posts bolt to the cabin sides and to the roof. The whole arrangement can be taken apart and lowered if the boat is going to trailer any real distance. Probably a few hours work taking down and setting up.
I don't want to trailer the boat at high speed with the roof up for fear of wind damage.

Eureka Moment

The interior of the cabin is 5'6"x 8'. The inflatable mattress is 3'3"x 6'2". I needed storage space, a place to steer, a galley, and a table and seats.

When I figured it out, and did the first rough install, pleased is too faint a word. Here is the first part of the solution. The table lowers and fits on cleats on the bins, and becomes part of the jig saw puzzle that makes up the base for the mattress.


The inside of "Grinder" came out way better than I thought possible, given the space constraints. Although the cabin is narrower and shorter than the "Bantam", it feels as big, or bigger.
I made very lightweight seating/storage bins from eighth inch okume and the quarter inch plywood packing crate that the okume came in. They can be moved around, and even stacked, to change the cabin layout.

The galley has a shelf that makes the final extension of the base for the mattress. So, on the port side, the two 16"x24" seats, the 24"x32" table, and the galley shelf all work as the mattress base. On the starboard side, another identical 16"x24" bin, and one 16"x50".
The starboard bins "L" to give more helm room.
To set the cabin up for sleeping, the table top lowers to the cleats on the two seats, and the starboard bins slide over next to the other furniture.

There is enough room, even when the bed is set up, to make some coffee, get underway and steer, or to go forward to the bow. Getting out the back door means stepping over the edge of the mattress.

An "Origami" folding tender and oars fit under the shelf/ seat you can see on the port side of the bow. How cool is that?

The engine, controls, instruments etc. will go in this Spring. Hard to wait.

"Grinder" First Impressions

Grinder went in the water June 28th. The weather has been mostly rainy and windy, so I have not had many chances to do water trials.

The engine is one of the new fuel injected Honda 40 HP four strokes. The prop is an 11" by 13" pitch 3 blade.

The testing so far shows a hull speed of 5.8 knots at 2200 rpm, then the boat gets up on plane at around 3500 and 11 knots. Both these speeds are pleasant cuising speeds, with little noise and good fuel economy. WOT speed is 21 knots, but that is much too fast to be enjoyable.

There was an initial problem with spray. The water hit between the fenders and was thrown into the cabin. I bridged the first few fenders with fender plastic, and added spray rail of indoor-outdoor carpet at the bow. Very little spray comes aboard now under most weather conditions.

Here's video of a high speed pass.

My wife and I slept aboard soon after we put it in the water. The cabin arrangements worked even better than I had hoped, with the exception of the inflatable mattress. It worked, but I found that 2 self inflating camp pads work better, and one of the pads can be used for napping on the bench/storage boxes.

I'll post more about the interior later.

Another Beauty Shot

Here is a photo with a little more detail. Now that the weather is better, we are using "Grinder" a lot.
When it is moored, the galley and helm are covered with vinyl. The bilge pump works very well. If it has rained, we stand on the stern and the pump goes on and takes out most all the remaining water.

And here's another video of a pass.

You don't want to go this fast in choppy water, but it's fun to let it rip occasionally.

Cabin Set Up

Here are some photos of the cabin arrangement. The boat is loaded with supplies (food, clothes, bedding, etc.) for a one week trip down the Hudson River.

Here is the cabin set up with the privacy curtains in place.
We did a trial sleep-aboard with the new side by side self inflating mattresses. Very comfy, and easier to get around with the aisle in the middle free.
The boat weighs 1750 lbs. with everything aboard: 15 gallons of gas, auxilliary 3.5 hp motor, bedding etc.
We'll see how it does on the river trip.

Hudson River Trip Glitch

We started our trip later in October than we would have liked because windy weather kept the ferry in port, so we could not get from Nantucket to Hyannis. We finally left on the 19th on the noon boat.

Here's a photo of the tow truck about to load our truck and trailer after the transmission failed on I-90, halfway to our destination.
The new plan is the Rideau Canal in June, and a new truck.

Hudson River Trip 2010

We found an '04 F-150 to tow Grinder, and took a four day trip up and down the Hudson the last week in September.
The intention was to cruise at hull speed, around 7 mph, but we ended up getting it on plane at 3100 to 3400 rpm and cruising at 11 to 13 mph. On plane the boat handles a chop better, and the noise level is still low. We used about a gallon an hour, maybe a little more, depending on conditions. Grinder has two 6 gallon tanks and a 3 gallon backup tank.
The big change in thinking was the cabin set up. We ended up keeping the table top down, so we had a bench on each side, with open storage under the table top part of the bench. We slept on the benches using self inflating mattresses and 40 degree sleeping bags. Very comfortable. We had a self timer on our radio, so we would go to sleep listening to some pleasant music in the background, and the radio would turn off after lulling us to sleep.
The absolute best things we bought were two "go anywhere" chairs. They were perfect for the helm on one side and comfortable seating on the other when we were under way, and then dockside when we were at a slip.

"Grub", a Lighter, Longer "Grinder"

Just finished a lighter, similar version of "Grinder" called "Grub".
Here's the new blog: "Grub a Camp Aboard Skiff".
Here is a video of Grub getting on plane.