Hi, I've been lurking on this forum for a while and am at the point where I would like to attempt to start my first CNC build. What is bringing me up short is the confusion over the huge wealth of options and directions available.
I understand that each machine is built to it's intended purpose and with a specific budget in mind, but it is not always clear which choices are wisest for a specific path. While steppers might be perfect for one, servo's are the clear choice for another. likewise a plywood table is fine for one application and ludicrous for a different scenario.
I am working on a design currently and learning what I can but could really do with some specialist advice from the crowd-mind.
Myself and a good friend have a number of decades worth of mechanical and electrical experience, and would really like this first one to be somewhat useful at the very least.
With all that said here are the basic requirements:
=============================================
3 Axis
Minimum area 2ft by 3 ft with a 10" Z axis
~$3000 excluding software and computers
Capable of Milling aluminum with close tolerances.
=============================================
The conundrum as it stands is, at the price point I've stated what serves best. Where should we put our money?
Current areas where I could use any constructive advice include :
Servo vs Steppers. Which will we be able to continue to use as the machine is refined.
Ballscrews. For the application that I've mentioned what would be the ideal number, diameter and pitch we should design for? Is 30mm diameter too high? is 12mm too tiny?
Construction material. - What are the limitations of 80/20. This is more difficult to get in Canada (where we are based), is the simplicity of connection still worth it?
Guides/linear bearings, what kind of stats are we looking for in these?
Really the recommendations that could be pure gold are any hints or directions with regards to model numbers, suppliers, quality eBay vendors or manufacturers.
There is such a range of terribly manufactured cheap components out there masquerading as quality material that it has made me nervous about ordering anything from "Anonymous China Inc" This goes especially for eBay.
I understand this post is pretty general, but really anything on any of the points will help and I'm hoping people will be able to share what they are thinking for a similar machine and any stories of quality parts they may have encountered from a good source.
Thanks in Advance.