In this project I explored making a “3-sided symmetry” design with laser cutting. Also I choose a concept for locking the parts in place that is not sensitive to the typical variations in thickness for acrylic sheet (+-15%)
I made this rocket as Artist In Residence at instructables last July and took the parts for two more back home.
I dedicate this Instructable to emilyvanleemput, for her drive and talent in making Instructables and because it’s her 15th birthday. You can see her assemble one of the sets at the Mini Maker Faire in Kerkrade.
Step 1: Materials and Tools
The main tool used is a laser cutter. In this case this also the only tool (not counting the software tools: Inkscape on a Mac for designing and CorelDraw to cut from a Windows computer). I used a 120W Epilog laser cutter in the new workshop at Pier 9.
Step 2: Design
Then I determined where I wanted the circular parts. I set the line thickness to 0.2 mm to represent the laser cut gap width and taking this in account I drew a rectangular slot fitting the fuselage width. Then I copied this slot twice, rotated over 120° and joined them.
I did the same for the other two circular parts.
From the crossing of the three slots I checked how the three fuselage parts “overlap” and how deep the notches and cut-outs should be. Along the central line of the fuselage I made a pattern of rectangles with a width and alignment taken from that. Then I made two copies and on the resulting three fuselage parts, I made notches and cut-outs that “complement” each other.
I added a bunch of circular holes. Finally, for the bottom circular part (actually on top in the drawing) I extended the slots in to the circle cut-out, so it can slide over the tail fins.
I saved the design as a pdf to go to the laser cutting computer (file attached to this step
For cutting I used the settings prescribed by the manual for the machine: Speed 50%, Power 70%, Frequency 5000 Hz.
Step 3: Assembly
Start with the circular part with the slots running through the circle cut-outs. Select a fuselage part without a notch close to the tail fin and slide it in a slot, up to the top of the fin. Then add the other fuselage parts, the one with the notch near the tail fin as last. Move the parts around loosely till they are all in the slots up to the tail fin.
Put the rocket straight up and align the three fuselage parts. Push the circular part up to secure the parts. Do not apply too much force, just enough to keep it in place.
Slide on the other large circular part and next the small one, both pushing them in place with just enough force for them to remain in place.
Fuel the rocket with your imagination and take off!