I ordered another print from Shapeways and after some volcano-related delays, it finally arrived. Another good experience from Shapeways. Now that Sketchup 7.1 can do Collada exports, the process is easier but still, it does not have power tools for mesh editing, so it sometimes can be difficult creating a watertight model that passes Shapeways’ checks. Each 2-part case was a bit over $3 in “White, Strong and Flexible” material. (They’re small) and shipping for orders over $25 is free. Read the rest of this entry »
The SALAMANDER triple sensor boards arrived and are under construction by students in the Gadget Lab at the University of Louisville. We used a laser-cut mylar stencil from Pololu to stencil solder paste onto the pads, then students placed the parts and we reflowed the solder on a hotplate. These boards were previously hand-soldered, but we need 50 of them for the summer so that had to change. If you’re considering the hotplate method, it is very very good and you should try it. The Gadget Lab has a fancy “lab” hotplate but I have just acquired the $20 Target skillet and will try it soon with that. We do all the surface-mount parts this way, then stick on a few through-hole connectors. The staggered SparkFun connector footprint does hold the connectors in place nicely (though much better for the 3-pin ones than the 2-pin parts) Now we have 27 working boards, and the bottleneck has moved to testing and sensor calibration. One person’s bottleneck is another person’s summer research project!
Eagle layout for triple sensor board
This sensor board is for summer 2010 research students to carry out studies of sediment transport in streams. It’s for the SALAMANDER project: Serial Amphibious Linear Arrays of Micro And Nano Devices for Environmental Research.
It is mostly connectors with a few chips in between to sense ambient light levels, flow velocity and temperature. For the first time, I tried the SparkFun staggered Eagle footprints that are supposed to hold the connectors tightly during assembly and soldering. A solder stencil for the red pads is also on the way.
