I am building a CNC router using open build parts. I bought 1/4" spacers and ecentrics for my wheels. how big of a problem am I going to have for lining up the lead screw with the lead screw nuts. Dave
If you are using C beam then its not just the leadscrew you have to worry about, but also the wheels which must run perfectly aligned with the v grooves of the C-beam. A 1/4" spacer or eccentric is nearly 14 thou thicker than the 6mm parts normally used.
Theoretically you’ll be off .35mm and I say theoretically because the end plates may not be all that accurate. You can make up half with 1/8” spacers at the nut block. It’s just easiest to line it all up and see how far off you are and use thin sheet metal for spacers under the nut block spacers. As an alternative, you could contact the shop and ask them to trade out for the 6mm lengths. They’re generally pretty good about that.
Thank you both for your input. Awake in the middle of the night I came up with what I think will work. Because I have a machine shop in my shop with CNC milling I will measure the thickness of shim I need and then machine them out of alu. Dave