Hi All

I'm Ian. I've been reading various posts on the forum and find it very helpful - thanks to everyone who contributes to this body of knowledge.

I've always been keen to build my own CNC Router and have now started this with more intent as I need to build a machine to produce to support my R&D projects and manufacture smalle batches of prototypes (GPS tracking devices for livestock). I started off with a small X-Carve machine and Fusion 360 6 weeks ago and quickly realised that I will need to / want to buil my own machine. I've since build a first iteration machine (800mm x 800mm using 40mmx80mm extrusion, lead screw, v-wheels and acetal sheets for plates) and made a lot of costly mistakes, but have also learned a significant amount about CAD, CAM and machine operation. I'm now moving to design and build a second iteration.

The ultimate aim is to build a bench-top CNC router, able to cut mostly engineering plastics of up to 800mm x 800mm x 40mm with reliable precision and accuracy of 0.01mm at the most optimale speed (which seems to be 3500mm/min) and at 3200 resolution. Accuracy is important due to the products requirements and to achieve good surface finishes and potentially also cut PCB's. Ideally the machine will be housed in a sound/dust enclosure as it will be in my office and I will need easy access to it to build prototypes and keep an eye on small production batches. I may want to cut some aluminium plates for making prototype moulds. I'm not yet sure how achievable and realistic the above is as the budget is also somewhat limited, but I intend to build incrementally from the basics and add more automation and features later on (assuming I can define a good end-design in the beginning and build towards it).

So far I have the following items for my next iteration:

X & Y
3 x 800mm 1605 ballscrews, C7
3 x pairs 800mm Hiwin 15mm rails and 2 HGR15CA carriages per rail

Z
1 x 250mm 1605 ballscrews, C7
1 x pairs 300mm Hiwin 15mm rails and 2 HGR15CA carriages per rail

4 x Nema 23 motors, 4Nm (potentially need to change to closed loop steppers and drivers as step errors can ruin expensive components)

40mmx80mm extrusions for the frame (need to change these as they are not rigid enough - intended for 3D printers)

Blackbox controller (from Openbuilds), 24v power supply, limit switches (need to change to better controller and power supply)

I will shortly be posting a few questions have!

Ian