Before I started building anything I decided to put something down on paper about what I wanted, needed, and could afford. After a good bit of research I came up with this.

Criteria:
• Cutting speeds of 300+ in/min
• Over all rigidity of greater than 20,000 lbs. per inch of deflection
• Resolution of .0005” or better
• Fixturing systems for a 6” precision vise and sheet material
• 10” or better of z axis travel and clearance
Constraints:
• Budget of less than $2500 for complete machine.... haha
• Must fit through a 20” wide door
• Must fit in an area 6’ X 8’ with max overall height of 5’ with room to work around machine
• Must have the ability to be manufactured with manual mill, manual lathe, band saw, stomp sheer, hand brake, MIG welder, TIG welder, and hand tools
• Must run off of 110 volts

Features:
• 3.25 HP spindle with a 10,000-21,000 rpm range
• Precision grade collet with a TIR < .0002
• Anti-backlash rolled ball screws
• Supported shaft linear bearings
• Zero backlash flexible shaft couplings
• 270 oz.*in hybrid stepper motors
• Gecko G540 stepper motor drivers with 1/10th Micro stepping
• Full 3 axis control
• Resolution of .0002”
• Aluminum space frame chassis with stressed aluminum sheets for extra rigidity

I chose aluminum, because there was plenty of good aluminum pieces always coming though at the scrap yard. My design changed a lot due to what I could find that would work.

Lots of time at the drawing board eventually led me to this:


I ran FEA's on about every part of the machine to see what I needed to achieve my goal. Here are a few.




Then I started making stuff.









curved jaw couplings


WORD OF ADVICE:
For those of you with the Chinese supported shaft rails, CHECK YOUR SHAFT BOLTS. On mine, the holes were barely tapped and the bolts were all loose and partially stripped. Some of the holes were tapped so crooked, I had to make a new hole.



I have my eye on a set of beefy thk linear rails a friend has, but I will have to come up with money before I can get those.


First test of motion with a impact gun on the ball screw



For dampening I did a test with Right stuff foam, and it came out pretty good, so I will start with this and move up to more drastic measures if I feel the need.
The difference is clearer in real life but the video still gives you an idea.