You may be wondering why it’s taken so long to get your bricks. To make these bricks, we are pushing the edges of two manufacturing processes.
We are insert molding ABS around populated PCBs (circuit boards). Overmolding generally means the plastic is softer than ABS, and can be done at lower temperatures. We weren’t able to find an injection molder who had molded around populated PCBs with ABS, and we were told that the components would fly off the PCB under pressure. Luckily, we found the molders who were willing to work with us pushing the envelope forward. We have successfully encased populated PCBs in the plastic without losing the components!
Second, we are holding our zinc components to tighter tolerances that is standard for zinc. Casting dimensional stability and tolerances from the Tampere University of Technology states the recommended tolerances for zinc are .076mm along parting line (as seen in Table 3). Our tightest tolerance is .0005 inches which is .013mm, which is a tighter tolerance than .076mm. This has taken a lot of tweaks to our tool and the die casting machines themselves, but we are holding tolerances to one thousandth of an inch!