Make and Make Do  

By Rob Rohde-Szudy - Madison, Wisconsin - USA


Motor Well Modifications – Part 2
Review Part 1

Motor Well Slot Cover for the Bolger Light Schooner
…or other boats with similar motor wells

Last time we talked about some of the problems with the motor well on the Bolger Light Schooner, and dealt with the pain-in-the-butt slot cover. But unfortunately, that wasn’t enough for me.

To review, Bolger drew the schooner for a 2hp, 1 cyl motor, which barely fits. Here in “Beerbratistan” itty-bitty motors are much more expensive than the 5-20 hp models favored by fishermen. So I have a Johnson 5.5, which is every bit as large as a modern 15. This presented a problem in the schooner, because the motor couldn’t tilt all the way up. In fact, it couldn’t even clear the slot until I cut a notch in the motor well bulkhead.

Obviously, I lose freeboard this way, which is probably not good. Also annoying was that fitting a noise deflecting hood would be much trickier, assuming I ever got around to it. Worst of all was the lack of clearance for fitting the motor with remote controls. The motor well decks are flush with the “transom” that holds the motor. You need a few inches below the top of that transom for the cables. Otherwise the cables have nowhere to go when the motor is tilted up. And you need it clear all the way to the side of the boat if you want remote steering too.

That pushed me over the edge. It was time to rebuild this thing properly. My idea of “properly” is a Michalak-type slop well forward of the motor. Here’s one on an AF4B.

This one doesn’t have the air boxes beside the motor like on the schooner, but the well in front of the motor provides space for the motor to tilt up without losing freeboard, and lets the splashed water and leaked fuel drain easily.

Changes already made

I had already made some changes to the design. I had widened the motor well from 8” to 9”, and I’m very pleased with the result. It is just enough room to get the slot cover in and out. 10” might be better. But 8” surely isn’t enough for the bigger engine.

I also decked over the rear “pockets” next to the motor well. I think everyone does this to the light schooner. You need the buoyancy back there if you ever capsize, and you don’t want pockets for gasoline vapors to collect and explode. Deck the pockets over and those vapors drop right out the bottom.

Motor clearance

The first thing to do is figure out how much clearance the motor needs. Tilted all the way up, the top of this motor is about 12” forward of the transom it’s clamped to. The schooner design only allows 7”. I decided to give an extra inch just in case, so the motor well bulkhead needed to move forward 6”

I was toying with remote steering the motor, so the other important dimension is how far below the transom clamp the steering sheaves will wind up. These are about level with the decks underway, but when the motor is tilted up, the cables interfere with the flush decks. So the motor well decks would have to be cut away by at least a couple inches. Again, I allowed an extra inch to make things easier.

New bulkhead

This part is actually pretty easy. First I marked a lines roughly 5” and 6” forward of the old motor well bulkhead. A heat gun and putty knife removed the bulk of the old paint, and the belt sander finished up. The object is to obliterate those lines, since they represent the glue lines. We want nice fresh wood. It’s pretty hard to get it well-sanded up under the decks, but get as close as you can. Modern adhesives will do the rest. When we have bare wood, we re-mark the line 6” for’d of the bulkhead. This will be the front face of our new bulkhead.

Now we get to do one of those simple procedures with fancy names – spiling. It’s not a big deal at all. Cut a piece of scrap cardboard to fit the new bulkhead’s plane fairly closely. It only needs to be close enough that you can tape it in place.

Then find an oblong scrap of wood and cut a point at one end. This is your “tick stick”. An irregular shape is preferred, so it can only fit one way. Then you put the point in all the corners you want to mark on the final stock, and simply trace the shape of the tick stick on the cardboard. Be sure to get all the points you want the first time, because you’ll never get that cardboard taped in the same way.

Here’s the cool part. Remove the cardboard and lay it on your plywood. Now when you match up the tick stick to the marks on the carboard, you can trace the point onto the plywood and replicate the corner points of the final bulkhead.

Then connect the dots. If you are a confident sort and don’t mind buying more plywood, you can cut right to the lines. I did. PL400 can fill gaps to 3/8”. (Mine were smaller, but not small enough for Titebond III.)

To get it in place I had to cut a bit off the upper corners and from the hidden part of the slot that fits around the deck carlins. Because of the boat’s taper, it still took a hammer to get it into place. It never would have fit with the framing sticks already attached, so these have to be added in situ.

Now you have a choice. You could fit this bulkhead by stitch & tape, which requires no further wood-cutting. I hate it because it is messy and I’m not good at it. So I fit this one by nail & glue, just like the rest of the hull. This means ripping some frame pieces. Getting the bevels from that piece of cardboard, we rip some 1x framing sticks. Bolger calls for 2.5” wide, and that’s what I did, using a circular saw with a rip fence.

But to make framing we need bevels. Lay a bevel gauge or divider against each edge to get the bevel. Be sure the gauge is standing 90 degrees off the cardboard, or your bevel will come out smaller than it should. I use a square to make lines on the bulkhead perpendicular to the edges. Line up one leg of the bevel gauge with this line and record the bevels. I dry fit all the parts first, bottom then sides then top.

Not much to it, really.

Trace these angles on the cardboard pattern so you don’t have to go to the boat and measure for every cut. Also record the bottom-to-side bevel while you’re at it.

The only real “hard” part of this was getting the boat partly off the trailer so I could get screws through the bottom. I untied the boat from the trailer and tied the light bar to a tree, then towed the trailer forward, about 4 feet out from under the boat. Then I tied down the forward end of the boat, so it wouldn’t fall off the trailer, and untied from the tree. Afterward, I got the boat back in place by using the same tree to shove it back on the trailer.

Back to the bulkhead. After dry fitting everything, I took it all apart and moved the bulkhead just far enough to get PL400 in the cracks. Then it’s a simple matter to glue and re-screw. The hull is watertight again, even though the project isn’t done. Could be handy. Of course it’s not as watertight if you added hatch cover frames like I did. We’ll get to how that works later.

Next time we’ll start chopping out old stuff.

Rob Rohde-Szudy
Madison, Wisconsin, USA

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