Testing

I took my Michalak designed Vireo 14 rowboat, Sandpiper out for some fairly extensive testing, with and without several passengers between 2 and 42 years old, this week.

She weighs about 63 lbs., according to the bathroom scale. This turns out to be a bit heavier than ideal - for me to lift her onto the roof rack by myself is awkward, since there's no thwart at the balance point, and I end up supporting a lot of weight on my head, which can give your neck a crick if you lean wrong. Or else I have to muscle it around all with my arms, which I'm barely able to do.

Wrestling it off the car and into the water singlehanded was a bit of a struggle compared to throwing around a fiberglass kayak, but it was doable.

But back to how she rows. By the GPS, I could row vigorously and average almost 5 mph (8kph) rowing across a small lake. This was fairly energetic, and I kicked up a bit of a wake. Top speed registered on the GPS was 5.9 mph (9.5 kph).

If I dropped the speed down to between 3.5 and 4.0mph (5.5-6.5 kph), rowing became about effortless, and the boat hardly made a ripple in the water - the rings left by the oars dipping in the water of the still pond were the most prominent part of the wake. So I think I could cruise at about 3.9 mph for hours. With a few kids aboard, or a couple kids and and adult, it wasn't really any more effort to row, if the weight was distributed evenly. But it was easy to mess up the trim if even one person was off center or if all the passengers were in the stern.

Afloat. She glides along nicely, and looks like she'll hold the whole family and gear, comfortably.

Unfortunately, my worries about how I mounted the oarlocks turned out to be well founded. When I drilled the holes through the gunwales for the oarlocks, I worried that the gunwales might not hold up to the strain of heavy rowing, and sure enough, one gunwale has started to crack around the oarlock. I'm going to use epoxy, some bolts, and some plywood to try to shore up that part of the gunwale. Won't be particularly pretty, but I think it's necessary.

Repairs

The Design

Jim Michalak’s plans for the vireo 14 call for gunwales from two strips of 1” x 3/4” wood, to make 1” x 1.5” final wales . A friend of mine cut and planed some 16 foot lengths of clear southern yellow pine for me, and the extra length helped me bend them to shape. I epoxied and screwed (stainless screws) one wale to the 1/4” plywood sides of the boat, then epoxied and screwed the second strip to the first. The design doesn’t specify how to mount oarlocks to the wales. I settled on some bronze oarlocks that mount through the wales, rather than inside or outside. The oarlocks I ordered had a rectangular plate, with holes for two mounting screws.

First wale on

Beginnings of the problem

My workmanship being what it is, I didn’t entirely fill the epoxy joint between the two strips. There were a few places you could see a crack or gap.

I had to decide how to mount the oarlocks. Since the joint between the two strips falls in the center of the wale, do I drill holes there? Or do I avoid the joint and mount them in the inner or outer half of the wale? I decided, since the oarlock needed a 5/8” hole, and each strip was only 3/4” wide, I’d be best off drilling the hole in the center. However, I mounted the oarlocks at something of a diagonal (see photo), so that one mounting screw was in the inner lamination, the other in the outer lamination. Although this may look odd, I felt much better not driving both the oarlock and the mounting screws into the joint, practically taunting the joint to fail.

I mounted the oarlocks at something of a diagonal, so that one mounting screw was in the inner lamination, the other in the outer lamination.

Here’s where another problem came in – I drilled a 5/8” hole for the oarlock with a spade bit, but it was not quite a perfect fit. The hole was a little too snug. After an ineffectual 15 minutes trying to slightly enlarge the hole with the drill and a tiny file, I decided good enough, but in retrospect, it wasn’t. I tapped the oarlock into place and actually had to give it a few good knocks with a hammer to seat it down in that tight hole. The mounting screws went in fine.

The joint starts to fail

I’m six foot three and though I’m no Lance Armstrong, I do put my back into it when I row. I had epoxied some two-by-fours to the floor of the boat to brace my feet against when I pull. I did some fairly hard rowing with various amounts of human cargo (up to 425 pounds, 200kilos, including me) and didn’t notice any problems (I wasn’t really looking, though). Then I let a passenger take the oars, and as he rowed, I noticed a few things.

When you lift the oars too high, this happens.

a) he seemed to feel the oars would work better the deeper he got the blades, so he was lifting his hands high and then pulling on the oars, with the blades a good foot or two deep in the water.

b) This awkward angle put a lot of stress on the oar-boat joint. I think in a rigid metal boat, the oar would probably have popped out of the socket when he lifted his hands so high. However, in the vireo, the sides flexed a bit, allowing the oars to stay in the socket.

c) Not only did the sides flex, but the wale on the starboard side cracked both at the joint between the two laminations, and also within one of the laminations (see picture). The port side was OK.

So obviously I hadn’t built things right to stand up to a little hard use. Time for a repair.

The repair

My first thought was to put some bolts through the gunwale, from inboard to outboard, to hold it together. Bolts holding steel or plywood plates would be even better. The plates would compress and stiffen the wale where it had started to fail. And I’d dribble some epoxy through the cracks that had formed to close them up. Miraculous stuff, epoxy, they say. The last thing I wanted to do was remove and replace a wale. And the second to last thing I wanted to do was cut out and replace a section of wale.

Then I thought I could also make the wale deeper vertically to strengthen and stiffen the oarlock mount. So I set about adding wood to the wales around the oarlock.

The block, clamped in place and belt-sanded flush with outside of gunwale.

For good measure, two 1/4" plywood straps that fit flush to the inside of the boat and the outside of the gunwale and the added block, with three inch long 1/4-20 stainless carriage bolts. When I epoxy, I'll tighten these loosely to hold the joint. After the epoxy cures, I'll tighten them a little more and hacksaw off the extra length on the inside.

I dry fit all the pieces. Looks good to me. I’ll see if I can find time to epoxy it all together tomorrow or the next day.

Of course I watered my garden for two hours this morning, so that meant it rained rained rained this evening, soaking my handiwork before I got it epoxied. Funny, the wood pieces seem somehow bigger now! I knocked the blocks out, but those carriage screws aren’t sliding out again until the wood dries thoroughly, if then. Hmm…..

from above - this shows the damaged side with the cracks still showing - I tried to get some epoxy into them, but I'm sure I didn't get much in.