Tacos are tasty, but annoying. The shells try to fall over when I'm making them, their contents partially spill out when laying on their side on my plate, and I needed an excuse to play with the laser cutter again. So I sketched out and made this acrylic dual taco holder.
I made this at TechShop www.techshop.ws
Step 1: Materials and Equipment
Vector drawing software (I used CorelDraw)
Laser cutter (my TechShop has a Trotec Speedy 300)
Acrylic strip heater
Acrylic sheet folding tool
1/8" acrylic sheet
Step 2: Measure a Taco
Seriously. You have to know how big the shell is before you can make a holder for one. The brand we regularly buy is about 5" in diameter as shown in the picture. To plan the holder I added a couple of rectangles to mark points of interest. Then, using the 3-Point Curve tool I drew in the base. Then using the 2-Point Line tool I added the two vertical supports. In the first few attempts I didn't like the shapes so simply deleted the red lines, resized the rectangles, then redrew the holder profile. The reason for using the rectangles is it let me easily make a symmetric design.
Step 3: Make a Top Down Guide
Again to make it easier to create a symmetric design I dropped down a series of rectangles. I sized the three large rectangles from the profile in the previous step. CorelDraw reports the lengths of line segments (including arcs), and I used that to get the 2" and 3.25" horizontal dimensions. Two tacos standing up against each other are about 2" wide at the top, so I decided to make the widest points of the holder 3" wide. I then added the smaller rectangles to help define the openings in each vertical piece and the narrowing of the base in the middle.
Step 4: Draw the Top Down Profile
Using a combination of the 3-Point Curve and 2-Point Line tools I drew the top down profile of the holder. Make sure you use the hairline setting for the profile so that these lines will be cut and not engraved. Once you like the shape, delete all of the guide rectangles. I added two black lines (to be engraved) to show the fold lines on the holder (in hindsight it was pretty obvious where the folds would be and I could have skipped this step).
Step 5: Laser Cut the Acrylic
Acrylic cuts and engraves quickly and easily. For engraving I used 100% power and 80% speed, and for cutting I used 100% power and 0.7% speed.
Step 6: Fold the Ends Up
An acrylic strip heater generates a line of hot air that will locally heat and soften the acrylic for bending. The acrylic sheet folding tool can be positioned and locked into place so that the acrylic can be bent to a specific angle. For this holder I set the angle to 105 degrees (so that the ends will be folded slightly back onto themselves). Line up the first end of the holder over the hot air opening, and after a few minutes the acrylic will be soft enough to bend. Bend the end up partially by hand then press the holder into the folding tool. Hold it in place for a few minutes to allow the acrylic to cool and set in position. Repeat the same heat and fold process on the other end.
Step 7: Bow the Middle of the Holder
I wanted to curve the base of the holder, and the strip heater doesn't heat a large enough area. So I placed the holder over the hot air opening, and shifted its position every minute. This slowly heated the entire middle of the holder, which I was then able to bend by hand into a gentle curve. This completes the taco holder!