Wednesday, May 8, 2013

Chapter 9 - Deck Raising

Chapter 9 – Deck Raising
With the redwood sill plates in place I could begin raising the deck framing. Thanks to a nice flat concrete floor, the center posts stood in their proper position all by themselves. I considered this a good start and a very good sign. My enthusiasm lasted until I picked up a sill beam with my trusty engine hoist, wheeled it to the concrete wall and discovered that the front supporting wheels crashed into the concrete wall well before the sill beam was anywhere near the top of the concrete wall. It was already time for plan “B”.
Fred, my car mechanic in Pennsylvania, was very enthused by my project. He decided that I needed a cart to move timbers around. One day we went to the junkyard and bought the rear end of an old Dodge. After shortening the wheelbase to about two feet and welding the ends together, he crafted a 1-foot square steel plate and welded it to the axle between the two wheels. He reasoned that I could balance my timber on this plate and wheel them wherever I needed them to go. He was right, except that the plate was very near the ground and getting the timber between the wheels proved challenging. I eventually solved this dilemma by attaching an 8x10 block to the plate, which put the supporting surface at about the same height as the tops of the wheels. Balancing the timber on this extremely rocky axle proved impossible, but shifting the weight towards one end and picking up the other end was easy. Pushing the contraption led to another problem. The timber easily slid on the surface of my block and the other end promptly buried itself in the ground. A ratchet strap came to the rescue. Wrapping the strap around the plate, the block and the timber and cranking it good and tight solved the sliding problem.
Plan “B” involved wheeling the sill beam up the loop driveway to the back of the foundation and dropping it onto the foundation wall. The next problem was that I could not push or pull that 600-pound mass up the hill! This time a rope came to the rescue. I tied one end of a rope to the cart and the other end to my truck trailer hitch. I quickly realized that I would be dragging the end of my planed and sanded timber down the driveway and grind the end to a pulp. Another ratchet strap clamped a sacrificial board to the under side of the end of the timber and solved this problem. Now the only trick would be turning corners. Since the cart turned easily, it was just a matter of turning the timber at the corner in the proper direction and starting again. Since the cart has no brakes, I quickly learned that a long rope was a good idea and going downhill was a bad idea. Despite all these learning curve type troubles, this cart came in very handy for moving timbers throughout the project.
Another Fred invention was a steel plate that bolted to the bottom framework of my engine hoist. To this plate was welded a 2-inch square steel shaft that fit into the receiver of my truck mounted trailer hitch. Though positioning the engine hoist at the proper height to slide into the receiver took some practice, once inserted, my truck became a wrecker. This invention eliminated the long support legs of the engine hoist. I could back the truck to the pile of timbers, put a strap around the timber, hook the other end of the strap to the hoist hook, crank the timber into the air and drive away with it. The problem with this, of course, is that the end of the timber wants to swing around and smack the truck. Two guy lines between the end of the timber and the truck solved this problem. Now I could back the truck into the daylight foundation and place the beams right on the foundation edges. I quickly learned however, that a 40 by 40-foot area is really small when trying to maneuver a truck turned wrecker. Beyond placing the edge sill beams, the wrecker would best be used outside of the foundation.
The cart trick worked fine for the four sill beams accessible at ground level at the backside of the foundation. The two front sill beams were easily placed with the wrecker invention. With the sill beams in place at the edges of the foundation, I could begin to place the cross girts. The steel straps that were embedded into the concrete and protruded through slots in the redwood sill plates not only helped to keep the sill beams from falling off the outside of the foundation, but had been measured to define a perfect square. If all the beams fit within the straps then the structure would be square as well.
By now, I realized that driving the truck around inside the foundation with a timber dangling from the end of the crane was a bad idea. The truck was just not capable of the fine maneuvering that would be needed to exactly place these girts. Besides, I definitely did not want to smack anything into my precious toilet that was perched right in the construction zone! The engine hoist on the nice flat concrete floor would work much better. However, placing half of the girt with the mortise and tenon at one end in the sill beam at the other end on a freestanding post was also a bad idea. What I needed was a temporary support for the inside end of the half girt while I engaged the end mortise and tenon in the sill beam. With the first half of the girt supported, I could then raise the other half of the girt.
The solution to this temporary support problem presented itself upon the arrival of the wayward joist bundles. Although the idea that popped in my head was going to be a lot of work, it was the only solution that I could think of. I re-stacked the bundles of 6x8 joists into a square pile, log cabin style, until the pile was just below the height of the sill plate.
Leaving a space between the concrete wall and the joist pile and placing the joist pile near the center of the half girt allowed me to lift the half girt with the engine hoist and roll it between the joist pile and concrete wall. Lowering the half girt onto this support structure with a few board shims under it to raise its end slightly above the level of the center posts allowed me to slide the half girt tenon into the mortise in the sill beam. I then adjusted the board shims to make the girt approximately level. Next, in order to get the scarf joint end of the first half girt in the correct position, I hoisted the center cross beam into place. One cross beam tenon slid into its mortise in the sill beam scarf joint and the other tenon rested in the bottom half of the girt mortise in the center of the girt scarf joint. Now, I could raise the other end of the girt by sliding its sill beam tenon into the sill beam scarf joint mortise and the girder scarf joint engaged its other half and produced the top half of the crossbeam mortise and the finished girt.
With the three major beams connected and supported by the joist pile, I now needed three support posts that would hold this structure level. The modern way to insure levelness is with a laser level. This being a low-budget project, I used a more ancient and simple method. I had initially stretched a string from one sill beam, across the foundation to the opposite sill beam. This gave me a rough idea of how thick my board shims needed to be to make the girt level and a rough idea that the girt stretched straight across the basement. However, I quickly realized that forty feet of string sagged way too much and if I cut posts to the height of the string, I was going to make my girder sag, just like the string! To find the center post height that would make the girt level, I attached a long plastic tube full of water to the sill beam at one end of the girt and the other end of the tube to the girt where the center post under the scarf joint will rest. This device is known as a water level. With a bit of adjustment of the amount of water in the tube, I made sure that the top to the water level in the tube was even with the bottom of the sill beam. Measuring from the concrete floor to the water level in the tube at the center-post position gave the exact height of the center post (94 11/16 inches) that would make the girt level with the bottom of the sill beam. After cutting an 8x10 post to this length, I positioned the post under the scarf joint. With the engine crane, I lifted the first half of the girt enough to remove the board shims and lowered the girt onto the top of the center post. Then I moved the sill plate end of the water tube around the inside edges of the sill beams to be sure that the girt was really even with all of the sill beams. Being thrilled to find that the water level really did match the level of the sill beams all the way around the back half of the foundation, I confidently cut the other two posts to fit between the girt and the concrete floor.
Before I could permanently install my three supporting posts, I needed to install a 6x8 cross beam for the stairway landing and the mortises for the two perpendicular landing beams. The plan called for the stairway to have thirteen steps and the landing to be seven steps above the concrete floor. I measured from the concrete floor to the top of the girt, and added the planned thickness of the 1 1/2-inch decking and 3/4-inch thick finished flooring. Dividing by thirteen and multiplying by seven gave me the height of the landing surface. Therefore, the landing beam was installed 1 1/2 inches below this level to account for the 1 1/2-inch thick landing boards that would rest on the landing beams.
The rest of the framing of the back half of the deck fell into place quickly. I hoisted the other two crossbeams into place and lowered them into their dovetailed joints. Then the four sets of six joists were hoisted into place and dropped into their dovetailed joints. After cutting two more posts and three 6x8 landing beams, I installed the rest of the stairway landing.

Using the four landing posts as an indication of the height of the sixth center post, I cut this post and installed the 8-foot long cross beams on either side of the central box and rested them on top of their center posts. I was now ready to repeat the installation of the other girt. Using the same stack of joists to hold up one end, I placed the first girt and slid the end 8-inch tenon into the sill beam and the tenon of the cross beam into its mortise in the girt. The other half of the girt was a bit more complicated since the girt and the 8-foot long crossbeam had to be connected before being lowered onto the scarf joint. With the 8-foot cross beam barely into its mortise and a shim under its center on top of the center post, I slid the crossbeam tenon into the girt. Then this assembly, supported by the engine crane was pulled back to engage the other mortise and lowered onto the scarf joint. On June 20, 1996, the back half of the deck framing was done.

 Next came the framing of the daylight basement opening. It was now near the end of June and this seemed like a good time to take a break. Having an invitation to explore the San Juan Mountains over the Fourth of July week, I filled in the time before leaving with some neglected trivia like sharpening my chisels. I also made a few small parts that would be needed for the construction of the west wall such as small braces and posts for the end of the concrete wall return.
 The original plan was to use the daylight opening for two garage doors on either side of a central entryway. When the concrete was poured, I had the concrete guys install bolts in the edge of the 2-foot return of the concrete walls at either end of the opening. I used these bolts to attach a 6x8 post to the edges of the concrete wall returns. The first thing I needed was two central girt support structures to form the central entryway and the opposite side of the garage door frames. Since I wanted a window on either side of the entryway, I made two sets of H’s with high and low crossbeams. The center door frame posts are 8x10s. The rest of the structure is made from 6x8s. I again used the water tube trick to establish the height of all these posts to insure that the girt would be level.

  Contemplating the raising of the two girt halves presented another new problem. Each half would need to be raised above the H’s in order to fit the top tenons of the H assemblies into their mortises on the underside of the girts. This meant that the center end of the girt would need to be supported without the crane so I could use the crane to lift the H assemblies off of the floor and into position under the girt. By now I didn’t have enough joists left to make a tall enough log cabin style pile as a support. At this point, I constructed what was to be the most valuable tool in my arsenal of lifting devices, a gin pole.
My first gin pole was a 10-foot long 2x6 board with a large eye bolt installed near the top of the board. I then hung a block and tackle from this eye bolt. I soon learned that a gin pole has the disadvantage of not being self-supporting like the engine crane. I cut a notch on each side of the board slightly above the eye bolt to provide a slip-proof connection point for three 1/2-inch 50-foot long ropes. Tying two of these ropes to the already constructed deck frame, I could raise this pole by blocking the end from sliding and pulling on the third rope until the pole was upright.

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