Centerlines

Mark on the beam of each frame and the transom the centerline, on both the fore and aft faces. Similarly mark the centerline on the stem on the aft face and on the bottom -- remembering that the bottom is currently facing upward.

Now, with the transom, frames and stem placed on their respective uprights, you will be able to sight down the center to line them up, at least close for now. Final alignment will come after all parts are in their proper vertical positions.

Leveling Frames 2 - 4 and the Transom

Frames 2, 3 and 4, and the transom, must lie level to each other all along their bottoms. Start by determining which of these parts is positioned highest relative to the others. Lay the level along the beam of that part to level it athwarships. Shim as necessary with pieces of thin wood, veneer, cardboard, paper... whatever works. Now clamp this frame to its uprights.

Now you can bring all these parts (2, 3, 4, & transom) level to each other, shimming as needed and clamping to hold things in place. Don't forget to sight down the centerline to make sure they still line up. Use a string line above or below the frames if you do not trust your eye.

REMEMBER: A tunnel boat rides on its sponson pads -- the bottoms of the sponsons -- not the tunnel plank. Make sure these frames and transom are flat and level along the pads. If, due to errors in making the frames, the beams are not also flat and level, then you have two choices: live with it, or fix the errant frames/transom. If your error is and 1/8" or less then you can probably live with it. Take a look at the situation and use your own judgement. If you plan to race your boat, then accuracy will be much more critical.

Now that all is level, flat and lined up, check it all again. Check for level from frame to frame, and along the beam of each frame. Use the level or other straight-edge to make sure the frames line up along the tunnel sides. Sight again down the centerline. Adjust as necessary, or if errors in the frames are discovered, decide whether to fix them or live with them.

Then go have a cup of coffee, or turn in for the night, or take a walk... and then check it all yet again.

Now that you are absolutely satisfied that all is perfect, consider going over it one more time.

By this time, you hate yourself for ever getting into this project, but that will pass. (But it will be back....)

Frame 1 and Stem

Frame #1 is positioned 3/16" lower than frame #2.

The stem is positioned 13/16" lower than frame #1.

Place frame 1 on its uprights. Since its correct position is only 3/16" below frame 2, it is an easy matter to lay a 3/16" drill bit or metal rod along the beam of frame 1 (see picture) to support the forward end of the level. Clamp the frame in position.

The stem can be positioned in the same way using a block of wood (or any convenient object) 13/16" thick to support the forward end of the level.

Final Attachment

Now that you have checked, re-checked and triple-checked to make certain everything is just as it must be, you can replace the clamps with screws. For the frames, attach with a screw through each bulkhead into its respective upright. For the stem, run a screw through the 2x2 into the aft face of stem. Same for the transom, through the 2x2 into the forward face of the beam. Remove all the clamps.

And then -- and you knew this was coming -- check everything again. And don't forget to keep checking now and then as the project progresses.

Now stand back and notice that this thing is starting to look a little bit like a boat.