[badhabit]

Hi,

I've had a lot of inspiration from this forum, so i think it is my turn to give something back. I've had an idea of building a large VMC for many years(decades?) and now i've finally come to the point where i'm building one. So this thread will contain the buildlog for my project, hopefully it can inspire others to follow through on their ideas. It is important to note that there is no major endgoal for this project. I have no vision of me making a living or whatever of this machine somewhere in the future. This project is all about the process, the learning, the development and the challenges. If this project should have a tagline, it would be "It's not the destination, it's the journey".

I've previosly made a gantry-styled router for full sheets:
Attachment 459702
... and here i've had my first experience with gcode, servo motors, endmills etc... It uses 2005 ballscrews, 25mm rails, clearpath servos and a Centroid Acorn as controller. I learned a huge amount on this project, among other things the importance of rigidity and mass distribution... I also had the plan to use this machine to help me making of the the next machine...

So i've spent a lot of hours drawing and deciding on a "knee type" or a "gantry type" mill. And i ended up with the knee-type working best for me. The rough design looks something like this:
Attachment 459704
Key information about it something along these lines:
- Height 196cm (my garage port is 200cm high)
- Weight: ~2500kg (~1700kg epoxygranite, rest is mostly steel)
- Controller: LinuxCNC
- Axis servos: CTB - 2,2kW on all axis
- Spindle servo: CTB - 7,5kW
- Spindle: Fuka FKS1201 with ATC and through-spindle coolant
- Rails: 35mm Hiwin RG rails
- Ballscrews: Hiwin 3010 ground C3

The decision making process for arriving on the above components are not based on clever math or elaborate spreadsheets. Rather i've been looking at how Haas or other professionals have done things and how other DIY projects have turned out. I started with the spindle and worked my way "backwards" through the mill. I did some calculations on the ballscrews, bearings etc, but nothing fancy. Then i've tried to make the best compromises for the project with a balance of "endresults" vs. price vs. time..

I've received the spindle and tested out the toolchanger and making sure i understood how the ATC and CTS works. Here is a picture of the spindle itself and my testsetup:
Attachment 459710Attachment 459706

I'm yet to have to servos running, because i'd like to make use of EtherCAT, but i'm having a hard time getting it working in LinuxCNC, i'll get there, for sure, but it is a steep learning curve:
Attachment 459708

I'm almost done with the molds for the EG. I'm using phenolic plywood("formply"):
Attachment 459712Attachment 459714