I am building a 17X20 overhead leadscrew CNC machine following the plans from Solsylva. The plans called for 1/2-inch ID conduit and 3/4-inch ID gas pipe. I found conduits that have ID of 5/8 and 1-inch, and OD of 3/4 and about 1-3/16 inches. Will these work?

We just finished building the large double-lead screw plan for his book...

I cannot answer your question specifically since I am currently at work, but you basically want to just go to Home Depot or Lowes and get their 1/2 inch electrical conduit and their 3/4 inch gas pipe...

Most of his materials are simply big box parts except for a few that you need to order...

We just finished our machine last weekend and are starting to get into the guts of the software...

Good luck,
Mark