Unfortunately, I got to the "tool steel" part of the program about the same time that the weather decided that the upper 90s wasn't hot enough. Since my shop and my garage are one and the same, and both are detached from the house and aren't air conditioned, once the temp inside the shop went over 100 degrees, I put things aside. Hopefully I'll pick this back up here soon.
Aside from the practical issues of heat stroke/heat exhaustion and sweaty hands/fingers not having the best grip or dexterity, a quick review of chemistry also says that working in this environment was sub-optimal.
As most folks are no doubt aware, galvanic corrosion occurs when there is an electrical potential between two materials (typically metals) while in the presence of an electrolytic solution (something that conducts). While sea water is most often cited as an example, human sweat has a remarkable similarity to sea water, and can more than happily fill-in as the required liquid. Throw in good tool steel (aka linear rails) and aluminum (the chassis), and my paranoia kicks in for keeping all sweat away from the machine at this stage of the build. Yes, it's paranoia, but I've also had to replace the aluminum handlebars on my road bike after two years. My sweat dripped down my arms, went through the bar tape, and collected where the steel strap that connects the brake/shifters ("brifters") to the handlebars attaches to the handlebar itself. I'm not excited about introducing any form of corrosion or other mechanical weakening into the system, so call it paranoia tempered with a dash of personal experience. Whether laziness is really the excuse and a desire not to work in the shop when internal temps are over 110 degrees, I'll leave that judgment to the reader.
My hope is that the temperatures will break here in another few weeks so I can comfortably get back to work on this.
In the meantime, Misumi announced a price increase effective for Oct. 1, so those interested in using Misumi products may want to do some investigations on what's changing and whether it affects their decisions.