Aggregate is a 3 dimensional building block that can be connected to itself in a variety of different ways to create unique forms. The proportions of the modules and the malleability of the material allow the pieces to be securely attached to one another with a friction fit. Approximately 125 modules can be fabricated in a very short time from a single standard 2" x 4" x 8' length of pine with almost no wasted material.
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Step 1: The Module
While the possible forms created by aggregating the units together appear highly irregular, they are composed of many simple and identical modules whose shape and proportions allow the pieces to be recombined in unique configurations.
Step 2: Select Your 2 X 4
The 2" x 4" x 8' is a construction staple and should be available at any hardware store or lumber yard in the USA. But just because they're easy to find, doesn't mean you should pick the first one out of the pile. Typically sawn from a softwood like white pine or douglas fir, a single 2 x 4 is relatively inexpensive and can cost anywhere from $1.50 to $10.00 depending on its grade.
While at first glance they might seem OK, pick up the 2 x 4 and hold one end up to your eye and stare down its length. You will likely see some warping from this angle that wasn't visible from its side. For this project we want the least amount of knots and straightest 8 foot length of wood possible. The 2 x 4's should be sorted by grade, with Select Grade A being the most blemish free and expensive, although Grades B + C should be suitable as well. In this case avoid the piles of common grade lumber as well as the pressure treated wood.
Once you have found your straight 2 x 4, you're ready to take it home and start cutting.
Step 3: Plane the 2 X 4
While your new 2 x 4 will be as straight and blemish free as possible, we will still have to remove material to smooth down the surface to our desired thickness. Depending on the equipment available in your workshop we can use either a planer, jointer or even a table saw to bring down the cross section of the length of wood to a consistent 1 1/2" x 3" for this part of the process.
You have probably noticed that the 2 x 4 has rounded edges in order to prevent splinters and make the wood easier to handle by construction workers on site. Additionally, the nominal dimensions of the 2 x 4 are different from the actual dimensions which are closer to 1 1/2" x 3 1/2". What we want is the 1:2 proportion of the short edge to the long edge so we will make sure to trim off excess material on the edges of the wood to 1/ 1/2" x 3".
It is important that the wood is planed to that cross section as the accuracy will determine how snug the friction joint of the modules is once they are cut and assembled.
Step 4: First Cut
We will now place a 3/4" wide groove on the wider edge along the length of the entire piece of wood. Measure 3/4" from the corner to use as the outside edge of the groove. The depth of the cut will be 3/8" deep.
To make the cut, use a dado set for the table saw to stack a 3/4" wide blade. Alternatively, if a dado set is not available, it is possible to make the cut with a hand router with a 3/4" flat bit using a straight edge as a guide. In either case, make sure that the depth of the cut is set as close to 3/8" as possible. It is best to test on a piece of scrap wood first to make sure.
Step 5: Second Cut
On the same side next to the first cut, make a second 3/4" wide and 3/8" deep cut 3/4" away from the opposite corner. If done precisely, there should be no excess material in the space between cuts.
Step 6: Third Cut
On the opposite side of the wood, make your final 3/4" x 3/8" groove down the length measured 3/4" away from the corner. Don't forget to lightly sand away any excess material or tear out that may have resulted from the cutting.
Step 7: Fourth Cut + Fifth Cut
Now that the length of wood is essentially an extruded cross section of the module that we want, all we have to do now is slice the length of wood like it was bread. Using the cop saw, set up a stop block exactly 3/4" of an inch away from the blade to streamline the cutting process.
With the jig you've just made, make two test cuts to check the tolerances of the modules. If the modules are too tight when connected, move the stop block slightly closer to the blade to make the modules thinner. If the modules are too loose when connected, move the stop block slightly farther from the blade to make the modules thicker. Repeat the process until you are satisfied with the balance between the strength and ease of the connection.
Step 8: Sixth Cut - Nth Cut
Once the thickness of the modules has been adjusted to the proportion of the grooves, use the stop block to align the rest of your cross cuts until the entire length of wood is used up.
Step 9: Putting It Together
Depending on how many times you had to readjust the stop block, you should now have at least one hundred identical modules that you can now assemble into a variety of forms and structures!
The related proportions of the cuts you have just made will allow the modules to be connected to one another in a variety of orientations and different adjacencies.
Step 10: Taking It Apart
Because the modules are held together by friction, the structures can not only be easily assembled but also quickly taken apart to form new custom forms.