This came about by studying the chart of brick cutting angles developed by JCG31 and the work done in the "Its time to go vertical" thread.
jcg31 has a great idea for cutting 2 or more dome bricks from a single brick with minimal cuts. I just took this idea one step further.
In his presentation he describe the use of c clamps and stops to hold the bricks while cutting and as this is very efficient from the standpoint of investing time in building a jig The clamps must be repositioned carefully each time a new chain is created.
Here is my table design and I will have a follow up to this describing the cuts to the bricks.
The table is simply two 2 by sixes that are attached to each other with hinges. A single larger hinge would be satisfactory.
The 1st 2 x 6 is just a base and a way to clamp or attach the cutting jig to the sliding saw table. The 2nd 2 x 6 both supports and provides a cutting angle for the brick. As you can see from photo number 1 and referencing JCG31's chart on bevel and angle calculations all of the bricks are cut at 5? up to chain 11.
This static angle would be true of most dome sizes even though in smaller domes the angle might be larger and in larger domes the angle smaller.
His calculations were based on a 42 inch oven.
When creating this jig the top board is cut long enough to support the brick on the left and the right, a groove is cut to allow the saw to cut entirely through the brick without hitting the jig, and a thin board is attached to the top at the 5? angle being used for most of the cuts.
After attaching the board at 5? angle it is cut through so the saw can pass. By attaching a single stick screwing it down and then cutting it later this guarantees that both sides of the jig are the same angle.
The bevel can be adjusted for every chain easily because the hinge between the 2 boards allows the angle to be propped up with shims or thin pieces of brick. I also put a long screw in the far left end of the upper board and screwed into the lower board to hold the angle constant and shims in place while cutting all the bricks in a particular chain.
Please view the annotated photos or feel free to ask questions regarding the jig.
Chip
Attached Files