Possible - New idea for brick cutting table

[mrchipster]

I think i may have come up with a very efficient and effective brick cutting table.

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

[mrchipster]

The cutting of the bricks then becomes very simple.

1) Set the desired bevel angle on the jig by shimming the upper board to the desired angle. This gets rid of the inverted V's.

2) Set the brick on the left side of the jig so as to remove enough of the right side of the brick to get a full cut on the brick. Make cut #1.

3) Turn the brick over 180 degrees, leaving the freshly cut side on the right.

4) Move the brick to the right to position for cut #2 and make cut #2.

5) turn brick over 180 degrees one more time, leaving newly cut side on the right again.

6) Move brick to the right to position for cut #3. and make the final cut.

You now have two identical dome bricks with 3 cuts.

Note: when cutting bricks into 3's it is advisable to cut both ends off of the brick before making the final brick section otherwise the brick section will be small and hard to hold.

Chip

[Gmcollins]

Great idea for a jig. It looks like it works very well. As a suggestion instead of a screw and shims why not use a coarse thread bolt from the bootom up into the 2x6 through a narrow pre-drilled hole. Similar to those adjustable feet on restaurant tables. That way you could just turn the bolt to get the desired slope and it would stay fixed without a shim. If one wanted to invest a bit more time you could use an embedded nut glued into the wood as well. Do you think this might work?

[mrchipster]

The only issue I have with the bolt is that the brick dust seems to get into everything and it might jam up after several brick cuts. even the head of the Philips screw needed flushed out before I could get a screw driver into the head. The hinges even get a little resistant to moving due to the dust.

The advantage of the screw is that it holds the left end of the table down when the brick is weighting the right side and that is important.

Chip

[Pompeii Nate]

Awesome jig Chip! I am glad there are minds like yours on this forum. Great job!