Tech Tips for small plywood boats

TANKAR's Tech Tips for small plywood boats.
Making the most of your mini-max or doodlebug type hull.
The problems
The wrong (and right) cure to try first
The wrong angle
The correct angle set up
Hook, Warp, and Rocker
"Old School" steering
Horsepower; How much is enough? How much is too much?
35 Horses on my mini max style hull.
25 and the hybrid:
Lower unit exhaust mod for a 1950's Evinrude Big Twin
My old mini max style boat
About the author

The Problems:

Low top speed on plane, bow "kniving" or steering wander, prop cavitation, hull deformities from mods, poor balance and lack of response to changes.

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The wrong (and right) cure to try first:

If your hull is true and not warped, hooked, or rockered, the best way to set up your motor's lower unit angle is to use the angle adjuster built right in to almost every outboard motor.

There are several different types but most that I have seen are simple pins with some sort of lock device that pass right through the motor's transom mounts and vary the distance that you run your lower unit "out" from the back of the transom.

Many people make the mistake of altering the hull's keel by thinning, shaving, or completely removing the last foot or more of the hulls keel. This will help somewhat with cavitation problems but simply altering the "out" setting or angle is a far better technique to try before altering your hulls strength and integrity. I have actually noticed that most home builders and first time riders of this hull never even try this method to fix the cavitation and handling before they make the keel modification. In the extreme worst case scenario, a hull modification like this can actually cause the most important part of your hull's wet surface running area to become warped, hooked, or rockered!

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About the author:

About the author of this page:
TANKAR is the name I use as a jack and master of all trades and I have lived on the shores of Lake Erie nearly all of my life
in Toledo, Ohio.

I spent summer months at an inland freshwater lake named Marble Lake in Southern Michigan's Branch County which is
home to a chain of seven man made lakes with the large and shallow Coldwater Lake at the southern end and Marble Lake
at the northern end. Marble lake is a nice sized piece of liquid real-estate and TANKAR spent weeks in both summer and winter on an island in Marble Lake called Treasure Island. It is with fond memories and even after years, still, a feeling of thanks to my old friend Bob and his family who had me there
every summer like a member of their family.

While there I had boat piloting privileges for a family fleet of one eighteen foot aluminum canoe, one sixteen foot aluminum rowboat, one Hobbie style catamaran sailboat, one twenty foot deck boat/pontoon boat, one Glastron sixteen foot I/O 120HP Hydro Tri-Hull, one ten foot balsa cored, fiberglass skinned three point hydroplane that was red and had a Merc Keikhafer Mark 20 with a bullet gearbox/lower unit, short shaft, and cleaver prop. Add to that my first semi vee stressed hull plywood skipper boat of my own design which had a twenty five HP Evinrude on it, a friend from across the lake's canvass decked doodlebug hydro with a ten HP Merc, and a couple of friends from the other nearby lakes who let me drive their super nimble GW Invader boats. One of them had a 40 HP Merc on it! As you can see, I have a lot of boating under my belt even as a teenager. My first boat piloting experience was when I was eight years old. My uncle Chuck had a thirty foot twin screw inboard Chris Craft cabin cruiser. He liked to go out on the boat but what he really liked to do was shoot the BS with his guests. He found out that I loved boats and we sort of teamed up for a couple of years. Eventually he was letting me head out from the dock and then I even began docking the monster. Not to mention that he just set me free on the lake after pointing out his directions. That is how I really started to love boating. Eventually I built a mini-max style hull of my own and put a way too large thirty five HP Evinrude Big Twin motor on it. After a lot of fun I finally tore the motor board off of the boat in a flip accident. I decided to get a fishing boat and relax for a while. I wanted a boat that I could afford and could trailer. I didn't care if it was an antique even (which is what I ended up with) because I was feeling like restoring a vintage boat anyway. I eventually bought a thirteen and one half foot 1958 Crosby early fiberglass hull runabout that had a plywood deck. After tearing off the old rotten deck I replaced a couple of rotted pieces of framework here and there and replaced the deck with some one quarter inch plywood covered with urethane varnish. After a while I re-arranged the cockpit by moving the steering back to the center console making it look like an antique bass boat of some sort which also made it a lot smoother and faster!

I eventually got tired of fishing and lately I've been itching to fly low again. I AM OFFICIALLY LOOKING FOR A RIDE HERE! IF ANY TEAM WANTS TO HIRE TANKAR HE WILL GO GET HIS APBA MEMBERSHIP AND EVEN HIS UNLIMITED LICENSE IF YOU WANT! JUST DROP ME AN E-MAIL AT tankar1@yahoo.com with your needs! TANKAR also has many skills above and beyond wood boat building and outfitting and driving. He is also a professional welder (15 years of various kinds of welding at an auto factory,) a certified auto mechanic (with more marine experience than most marine mechanics) and he is also a Citrix Certified Administrator in the computer networking realm.

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