Thermocouple vacuum gauge teardown and explanation

I describe how thermocouple vacuum gauges work, and take apart a vintage example of such a system.

Milling machine tutorial - cutter selection, speeds and feeds, coolant, high speed machining

I discuss the basics of selecting the right cutter for the job, choosing feeds and speeds, and general setup and planning of CNC milling machine cuts.

New high vacuum system

I'm building a physical vapor deposition rig, which will be an interesting tool for creating optical coatings, SEM sample preparation, and maybe even thin film transistors. So far, I only have the pump and Penning gauge connected to the chamber. Soon, I'll have high-current and high-voltage ports in the base plate for controlling the deposition process.

http://www.allorings.com/gland_static_axial.htm

Water circulator with temperature control

I built a water circulator that can supply heated or chilled water to various other shop projects. 

Eurotherm 2132 with platinum RTD (eBay)
CPC quick-disconnect hose fittings (eg McMaster 5012K79)

Intro to DIY Raman Spectroscopy

I've been working on a Raman spectroscopy setup in my shop for a while, and was finally able to collect some real, verifiable data this evening. Raman Spectroscopy is a technique where light is directed toward a target, and the reflected light is color-shifted by the size and type of the molecular bonds in the target. This is a non-destructive way to determine an object's molecular structure. The problem is that the color-shifted light is many, many times weaker than the non-color-shifted light. A Raman spectroscopy setup compensates for this, and allows meaningful data to be collected.