I researched several available mill drill combinations and mini mills that were available at the time.

 

I looked at the Sieg X3 copies, RF31 and 45 clones and full sized turret mills.

Cheap milling machines.

I Liked the super X-3, although it’s limitations seemed to be that it was kind of “light duty” and only 1 kW of power for the spindle. I had a look in the machinery shop and pulled hard on the head, there seemed to be a lot of movement in the connection between the head and vertical column. A small work table put me off in the end. If I was going to spend $2000, I wanted to be able to have a big enough work table to do larger projects.

 

The RF 31 seemed to be ok at first glance, although the round column was going to become a bit of an issue because when the head is moved up and down, it will also move slightly side to side no matter how careful you are, this will make you lose your reference location. In a CNC conversion, it would be impossible to automate the Z axis lifting the head, I would only be able to move the quill up and down. This is a big limitation when changing tools, it would only give me a small working envelope. The RF 31 copy seemed like a glorified drill press with a moving table. It was not much of a step up from what I had already out grown. 

 

The RF45 clone had all of the above problems covered, and as an added bonus the head tilts side to side. There was a fairly large work table, and a six speed gear driven head, with a quill. The head was fairly rigid, but after making the shop salesman put a dial gauge in the chuck, and pulling on the head, I discovered that there was still 0.05mm of movement when I put lots of weight on the chuck. There was approx 0.25mm of backlash in the leadscrews, but I figured I would be able to eliminate most of this with some modification.

 

The full size turret mill would have been a fantastic machine, coolant included, a big work lamp, and a huge table. The limitation was the size of my shed, it would just fit under the roof when I had to move it in, but I would require a small crane so lift it (Approximately 500 kg, or 1100 pounds,) and the crane would not fit in my shed to move the mill in. The cost was also approximately $2000 above what I could afford, so It was not an option.  

 

 

My New RF-45 copy .

^Grae-Tech