Aaaand it’s done. I have it. I received my eShapeOko. The only thing now that prevents me from mounting it is the threading of makerslide holes; this will be done on tuesday evening by my very good ham friend F1BHY. Many thanks to him, I’m very grateful for its dedication for his friends.
I also received new TRF7970 samples from TI. These are using QFN packages, and it’s quite complex to solder them properly the first time. Last time, I added too many solder paste and I ended up with components floating in a sea of fused solder. I could remove most of the surplus solder, but I fear that these components are short-circuited between the package and the PCB (only X-ray analysis could confirm that), and if they are not, I fear that I fried them with the hot air rework station.
These components will take place on a SeeedStudio board, which has tinned traces. With my previous experience soldering these components, I now believe the small solder quantity already present on the board is enough to solder the components correctly. All I need is flux, which I did not have before.
When it compares to QFN, soldering TQFP packages (for the ARM chip) is a piece of cake 😀
Now that I have a machine to work on, I’ll update you more often. Please note that I also started a build log at the ShapeOko forum. This forum is really interesting and contains a lot of wisdom, interesting upgrades and information about what to do and avoid. One of the most interesting mod is the replacement of the normal Z-axis screw by an “acme screw” with a trapezoidal screw profile. This sort of screw has a larger pitch, so the Z moves can be accelerated, which has a positive influence on the global speed of the machine (the Z axis limits the achievable speed on all other axes).