G0704 Phase 1 and 2 CNC
The Phase 1 CNC Conversion is a simple, easy to machine version that uses the stock leadscrews for the X, Y and Z axis. The stepper mounts are based on my X2 CNC conversion
but have been simplified for easier machining and to use less hardware. It is a dirt cheap way to get up and running quickly and making parts under CNC control. The stock leadscrews will be stuck with about .002 -.005 backlash, but it can be compensated for by using Mach 3's backlash comp. The stock bearings are also reused to save money. This version could provide very acceptable performance for a long time and could allow you to use CNC to make a more
advanced version down the road sometime. Nearly all of the parts made here can be used with the Phase 2 version which will use ballscrews and Angular Contact bearings.

The Phase 1 CNC Prints give you several styles of parts to choose from to match your experience or available equipment.
Stepper motor standoffs, a round version A and a square version B.
Stepper mounts using either round clearance holes or square (no boring head needed)
Z axis stepper mount using either a Nema 23 or Nema 34 motor.

Formats are in AutoCAD .dxf and windows .jpg

Phase 2 is the ballscrew version that uses many of the same parts as Phase 1.
It uses 5/8 Roton ballscrew with a square ballnut for the X abd Y axis and
3/4 Roton Ballscrew and round ballnut for the Z axis. The saddle needs
a small pocket created for the X axis ballnut and the Y axis needs some
casting flash removed from the base. It needs no major rework for installation.
The ballnut pocket could be milled, ground or plunged with an endmill on a
drill press, just need the clearance, the dimensions are not critical.
You can choose a direct drive Z axis version for either Nema 23 or Nema 34 motors.
The X axis motor can be mounted on either the left or right side of the table.
The conversion gives full travels of 19x7x15, xyz. The ballnuts can be repacked with
.1263 oversized balls to get the backlash down to almost zero.
Sources are Toolsupply and Bal-tec. Approx, 69 balls per nut.
A list of all parts needed is included with part #'s along with a stock and hardware list.
Initial testing using my recommended electronics with 570 oz/in N23 motors
on all three axis (direct drive Z) gives realistic rapid speeds (tested with full weight
on the table) of 200 IPM for the X and Y and 255 IPM for the Z axis. Videos below.


G0704 X Axis CNC with Stock Screw
  G0704 Z Axis CNC with Stock Screws
G0704 Phase 1 and 2 CNC Prints
Downloadable file only.
A link and password will be
emailed to you within 24 hours.
Visit our parent site Hossmachine.info!
x stepper mounted on left side as an option

x stepper mounted on left side as an option

X axis stepper

X axis stepper

z axis installed

z axis installed

x axis ballnut pocket

x axis ballnut pocket

G0704 X and Y Axis CNC with Ballscrews
  G0704 Z Axis CNC with Ballscrews
Repacking Roton Ballnut
G0704 Max Realistic Rapid Speed
Attention:
These conversions were designed for the G0704.
Attempting to use on any other BF20/25 type mill is "Use At Your Own Risk"
There are small differ-
ences between the models which would be most noticeable during the Phase 1 Conversion,
much less so with the Phase 2 Conversion as many stock components are replaced.

Notice:
These plans are intended for the DIYer. Novices with very limited experience should get the DVD-ROM version which includes many instructional videos and pics.
A ballscrew turning service is now available for the Phase 2 CNC Conversion.
Please contact
CJA Masterworks LLC
Now Includes plans for extending the
Y travel to 9.5 inches and the Z to 18 inches.
Watch the Video here! Also the option of mounting the Y stepper in
the rear!
Watch the Video here!
Check out the Phase 1 and Phase 2
CNC Conversion Tooling List
Requirements!
The plans now have prints
to allow using C7 ballscrews and nuts from Ebay. They can be ordered with the ends machined to fit the same Phase 2 CNC Conversion parts here for around $250.
Also mods to the X nut etc. needed to fit under the table.
All ordering info supplied.