Making the new ThirdLynx circuit board
The Optec ThirdLynx family is one of our most popular product lines. The ThirdLynx focus motors are used to automate an existing focuser with fully integrated electronics, no external controller required. But after several years it was time to upgrade the classic.
We knew that we wanted to make the new ThirdLynx use a USB C port instead of the USB B port on the original design. We also wanted to miniaturize the board, moving to a single board instead of a stack of two. This led to something new, Optec’s first four-layer PCB. While working on the improvements we also added an improved stepper driver and modernized some of the other electronics.
Each new PCB design is ordered from a prototyping shop with a matching solder stencil.
The stencil is a steel mask with holes where the solder paste needs to go to attach components.
After we get the bare PCB we hand build the circuit and extensively test the board. Any issues we find are fixed in revisions. After a lot of testing we move on to production.
Optec does almost all our design and manufacturing in our Lowell, Michigan office. This includes our electronic boards. We have a small Pick and Place (PnP) machine that we use to assemble our boards.
Because the new ThirdLynx uses a double-sided PCB components are placed on one side with a higher temperature solder paste. After going through the reflow oven the boards are brought back to the PnP and components are placed on the other side using a low temperature solder paste.
After the second reflow the boards are inspected, and corrections are made. Through hole components (often jacks) are added and soldered by hand. Then the boards are cleaned and inspected again. After passing inspection the boards are programmed and run through testing to ensure that all features are working properly.
Finally, the board is integrated into the finished product.
