Monday, April 21, 2014

EV battery pack replaced

The new 12 volt EV batteries have been installed. It went better than I expected! Nice surprise. The 8 new batteries shaved off 480 pounds of weight over the 6 volt ones but with their lower 150AH rating there will be a loss in range. Time will tell as I learn and record their performance.
 Plenty of room in the battery box.
 $1100 worth of replacements.

Used the rest of the week to work on models for the new log cabin.
First round of logs will require blind dovetail joints to lock in the 4 corners of the bottom logs.

With a saddle carved into the top of the first log the second log can be scribed and notched. The notch can be seen but the groove in the bottom of the log is hard to see. In the background of the picture you can see how it fits together when assembled. This process would continue until the walls are the desired height.

The top log is also the bottom chord of the King post roof truss. A lock notch will be cut to secure it in place. The lock notch design keeps more wood in the bottom chord notch area for more log strength. This is important because much of the roof load is carried by the out rigger perlin at each eave.

And the final result of the roof truss system mated to the cabin walls looks like this.

Next up?  The foundation logs and floor system.

Wednesday, April 16, 2014

Model cabin work

Model building will be the key to the success of this next cabin project. My design calls for a 12' by 16' cabin with a 5' deck in front. To get the feel for this area I laid it out with some boards I had on hand.

This is just the cabin area. The 5' deck will extend the footprint on the 12' wide end to the right.

I was pleasantly surprised to see that I had more logs than I had originally estimated and will put this excess to use in the construction of roof trusses for this cabin.

With 98 logs I decided to make a spreadsheet and sort them by length. This gave me a good picture of the quantity of each length that I had for construction.

After doing some searching and sketching I decided to use whole log King Post trusses with log perlins exposed to support the roof boards. Then if necessary go with a built-up roof on top for as much insulation as desired by the buyer.  I bought some 1.25" and 1.0" dowels and set about making a model of the King Post truss and perlins to help me visualize how everything would go together.

The trusses will extend beyond the cabin side walls by 3'. The final detail will be to model up how the trusses will mate up to the walls and the eave sofits be enclosed. To see this I will model a few rounds of the cabin wall. Because I will be using a Saddle notch so I will use my first model I made in 2004 for my first cabin to refresh my memory and then cut the dowels for the new model.

So for now I'll pause on my cabin model work switching gears to spend a little time on the electric vehicle battery change over from sixteen 6 volt batteries to eight 12 volt batteries.