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Desktop Mini Mill CNC Lead-screw Conversion Drawings  

Designed for the Sieg X2 , but should be suitable for other similar mini mills with different branding e.g. 

Harbor Freight Central Machinery (44911) , Cummins Toolnow (7887) 

Homier Speedway (03947), Chester Conquest , Sealey (Sm2502) ,Grizzly (G8689)  

These, and other mini mills, are said to be the same as the Sieg X2. Whatever your make, please see Basic Checking Dimensions below before purchasing, and please note that lead-screw lengths could easily be adjusted for the larger table/travel versions. 

The parts in this design have been thoroughly tested for many hours on a working conversion. Designed to be easily made using a small mill, and a small lathe, with minimum modifications to the machine, with no loss of travel in X, Y or Z. (See What you will receive, What's not included, Materials you will need, Design, and Price details below) 

Basic Mini Mill Checking dimensions (in mm)  

    (X) Table (excluding leads-screw supports): 385 long x 92 wide x 31 deep, 220 travel, with 72 hole centres for lead-screw support fixings (M6)

    (Y) Saddle: 150 long x 93 wide x 48 deep, 100 travel

    (Y) Base: 50 hole centres for lead-screw support fixing (M6)

Finished Machine

X and Y axes fitted

Z Axis 3D CAD image

Y-Axis 3D CAD image

What you will receive 

  • Complete set of fully dimensioned CAD drawings in PDF format, detailing all the parts and assemblies required to convert the X, Y and Z-axes to accept NEMA23 stepper motors.
  • A list of recommended material/part suppliers, and a complete list of fixings required.
  • A fully detailed 17 page, step-by-step Installation Manual with pictures, text and drawings. Supplied in PDF format.
  • Tips and advice on sourcing the motor and control parts, needed to complete the installation.
  • Drawings optionally supplied in DXF format to help with any intended CNC manufacture of the parts, and could save you a lot of time. See Optional DXF pricing below
  • Manual and drawings will be sent by email within 48hrs of payment being received.


Materials you will need:  

  • Lead-screws, mild-steel, 14x3 trapezoidal threads, (Matching or home made tap will be required.)
  • Black Delrin®, which is an acetal resin, engineering plastic, easy to machine. Free machining Aluminium (6082-T6/HE30) could be used.
  • Low cost sealed ball races, and thrust races, to mount the leadscrews.
  • White Delrin®, which is a highly effective bearing medium with a low coefficient of friction, extremely wear-resistant. Phosphor Bronze could be used


What's not included:  

  • Drawings do not include details of electrical wiring information. Normally supplied by the Controller/Motor supplier.
  • Details of swarf guards etc. Details of any home/limit switches.
  • You are buying the Drawings and Manual only. NO PARTS or materials are supplied.
  • This page shows pictures of the actual finished machine purely for reference purposes.



  • Designed for Home/DIY use. The typical uses that the milling machine itself was designed for. Not really aimed at production engineering applications.
  • NEMA 23 motors (not supplied) are assumed to have M5 clearance fixing holes.
  • Motor spacers have been sized to suit Lovejoy L050 couplings. Other flexible couplings may be OK, but check compatibility and dimensions before buying.
  • Nuts are adjustable for wear, and when correctly set should give about 0.05mm backlash (which can be compensated for in Mach3® software etc)
  • The conversion will disable the manual operation of the milling machine. However, if stepper motors with double shafts are employed then some degree of limited manual use will be possible. No modifications will prevent the parts removed from being refitted to re-create the original manual machine, if ever the need should arise.
  • The parts are designed to fit with the minimum modifications, by utilising existing fixing holes etc. However, 3 x M6 holes and 2 x M5 holes need to be drilled and tapped to fit the Z-Axis lead-screw, and a small modification to the saddle is required to fit the X-Axis lead-screw.


  Price for PDF documents ONLY  

£9.99 + VAT (US $15.00, EU 12 euro)  

  Price for PDF and Optional DXF documents  

£19.98 + VAT (US $30.00, EU 24 euro)

PDF Manual, PDF drawings and optional DXF drawings will be sent by email within 48hrs of payment being received.

Choose PDF DXF Option

Solution Graphics