Assembling the Frames

Laser level aligned with the center of the Strongback

With all frames complete we are ready to start assembling them on the Strongback and excited to start seeing the form of the vessel take shape.  As was mentioned during the Strongback construction, we used a Bosch crossbeam laser level to establish the centerline and horizontal plane.  Before starting, this was checked again and looked to be within 1/16" or so along its length. Plenty close enough for a material that shrinks and swells with temperature and humidity anyway.
Initially I was going to use the string shown in the photo (illuminated by he laser) as a guide to align the center of the frames but thought it would be a great idea to use the laser instead.  It proved to work well with a few practical considerations: 1. Start from the furthest frame and work toward the laser so as not to create a shadow from a frame set in front of another and 2. get these set in one day because it was tedious to realign the vertical plumb on the level.  Even turning the switch on and off will knock it out of alignment.
With that said we proceeded from Station 20 at the back and worked forward.  For this portion my Father was there to help as this is a two person job trying to steady the frames and screw them in place (temporarily) at the right height.
Using the plan below...


Top View of Strongback with station measurements along the top of the drawing

We laid out the stations on the horizontal deck of the Strongback on both sides and checked the diagonal on the first set of marks to be sure that we were square to the centerline.  Within 1/16" so I was happy. Now, let me stop for a second and explain myself.  I am not by nature extremely anal about such things.  I don't mention "diagonals with 1/16" to show out or "top the knob".  What I have learned over the years is that if you can get the foundation of anything as nearly perfect as possible, then you will find the rest of the project falling into place if you take reasonable care.  What can kill a project and turn it into an exercise in tedium is to have something a little un-square or un-level and then fight it with ever cut and corner from then on out. 

Station 20 Frame clamped and ready to screw into 2" x 3" horizontal support

Okay, with that said we started setting the frames. Remember that this is built upside down at this point.  What you see to the left is the first frame (Station 20) clamped off at the proper height measured from the deck of the Strongback. The horizontal member that the frame is clamped to is screwed in place to the Strongback. The ends will be sawn off flush when done.









To the right you see me screwing in the horizontal member before setting the next frame.  Now that we had established a proper height based off of the plans from the deck of the Strongback to the top of the upside down frame, it is time to center this using the laser's vertical plumb line.



Pencil center mark sitting in the middle of projected laser line.

To accomplish this without constantly rechecking the height, we clamped a temporary board to the frame resting on the  horizontal cross member and simply slide it back and forth until centered.  Here is a view of what I'm talking about in sequence of construction...

1. The C-clamp is holding the darker, horizontal board firmly to the frame maintaining the height of the frame. 
2. The blue clamp is released and the frame is slide left to right to align the centers.
3. Once centered, the blue clamp is reapplied to free the hands.
4. The frame is screwed in its final position and everything unclamped... next.

This was continued from frame to frame and took about three hours total...

Completed up to Station #4

 I have to complete the transom and stem at this point and they will be a page to themselves.  Then its off to the chine installation, and then ready to skin with marine plywood.

 

BTW... 6/27/2014

For those checking the blog my ply is on backorder.  I have a road trip ahead of me and am anxious to get back on this. Stay tuned and I'll announce new updates when I finally have material.

Thanks...

 

UPDATE!!! 8/5/14

 

40 sheets of 1/2" and 6 sheeets of 1/4"... No problem.

The marine ply finally came in. I agonized over what to buy, weighing benefit vs. cost.  I finally decided on Roseburg Marine Grade AB Fir.  If I weren't covering every square inch of this ply in either epoxy coated fabric or a layer of decorative wood, I doubt this would have made much sense.  The Fir can be a pain to get a good level surface on when sanding as the darker and lighter grain is of two different desities and it's easy to hollow out the softer grain while leaving the harder grain proud and the surface wavy.   I ordered from Menards, a midwest building supply.  The closest store was in Owensboro, Kentucky but well worth the drive.  The savings compared to what I would have spent locally was significant at almost 35% once the gas to pick up was factored in. 

Next I start cutting this up and move along with the project...