LifeTrac III/Manufacturing Instructions

Overview

LifeTrac is a low-cost, multipurpose open source tractor. It serves as a workhorse backbone for many of GVCS technologies.

Featuring a modular design and detachable PowerCube units, it has the ability to rapidly switch between a variety of GVCS machines via the QA Plate. The machine is overbuilt with a focus on lifetime design and ease of repair.

Four hydraulic motors provide skid steer power to the wheels, and a unique chain tread system enables navigation of fairly extreme terrain.

Preparation

Safety

• Hearing Protection
• Eye Protection
• Steel Toe Boots
• Welding
  • Gloves
  • Hood
  • Apron/Jacket

Workspace

This section describes the various workspace areas that we have found to be useful in fabricating the LifeTrac. It is provided as a suggestion for preparing your work area.

• Storage: For raw steel and parts
• Cutting Area: For use with cutting torch - Made from non-flammable materials
• Welding Table: Usually steel, suitable for use with arc welder (MIG, TIG, stick, etc)
• Ventilation for cutting / welding areas

Tools

• Welder
• Angle Grinder

• Hand Tools
  • Crescent wrench
  • Socket set
  • Hammer

• Metal Cutting Tools
  • Bandsaw
  • Chopsaw
  • Torch

• Paint Tools
  • Gravity Fed Paint Sprayer
  • Air compressor

Cut Sheet

• This list contains instructions for cutting the raw steel into pieces for assembly. Most will require further cuts before being ready for assembly.

3/8” Thick, 8" Plate

• 4 @ 12 1/2"

1/2" Thick, 4" Plate

• 6 @ 6"
• 8 @ 4" (cut each diagonally for 16 triangles)

1/2" Thick, 8" Plate

• 4 @ 6"
• 8 @ 10"

1/2" Thick, 10" Plate

• 8 @ 10"
• 4 @ 6 3/4"

1/2" Thick, 12" Plate

• 5 @ 12"

1" Thick, 8" Plate

• 4 @ 4 1/2"

1/2” Thick, 4" x 6" Angle

• 4 @ 6"

¼” Thick, 2 3/8" Dia Steel Tube

• 1 @ 4 1/2"

¼” Thick, 4" x 4" Steel Tube

• 3 @ 44"
• 2 @ 52"
• 2 @ 55"
• 2 @ 59"
• 3 @ 60"
• 2 @ 68"
• 4 @ 76"

5/16” Thick, 2 1/2" Dia Steel Tube

• 4 @ 5"

3/8” Thick, 3" x 6" Steel Tube

• 1 @ 45"
• 2 @ 100"

1 7/8" Shaft

• 4 @ 26"
• 1 @ 56"

Parts Fabrication

• The purpose of this section is to prepare the components for final assembly. This includes cutting steel into required

¼” x 4" x 4" Steel Tube

• Verify the following 4" x 4" tubes have already been cut:

• To simplify hole placement, here is an image of a jig (click to enlarge):

Tube Drilling

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• 3 Lower cross tubes, 60" long
  • Drill holes at 14", 46"
  • Rotate 90 degrees, drill holes at 2", 10", 50", 58"

• 2 Bottom Inner North-South tubes, 76" long
  • Drill holes at 6", 9", 13", 30", 63", 67", 70"
  • Rotate 90 degrees, drill holes at 2", 10", 50", 58"

• 2 Bottom Outer North-South tubes, 76" long
  • Drill holes at 9", 13", 63", 67"
  • Rotate 90 degrees, drill holes at 2", 34", 58 1/2" 62", 74"

• 2 Front Vertical tubes, 55" long
  • Drill holes at 6", 50"
  • Rotate 90 degrees, drill holes at 2", 46"

• 2 Middle Vertical tubes, 52" long
  • Drill holes at 6", 24", 50"
  • Rotate 90 degrees, drill holes at 2", 46"

• 2 Rear Vertical tubes, 59" long
  • Drill holes at 2", 21", 29 1/2", 47 1/2", 54"
  • Rotate 90 degrees, drill holes at 6", 50"

• 2 Top North-South tubes, 68" long
  • Drill holes at 6", 22", 62"
  • Rotate 90 degrees, drill holes at 2", 26", 66" and a 2 3/8" hole @ 48" (with cutting torch)

• 3 Top Cross tubes, 44" long
  • Drill holes at 6", 38"
  • Rotate 90 degrees, drill holes at 2", 42"

Assembly

• Use 6 blocks to support the 3 bottom cross members

• Place the 4 bottom North-South members on bottom cross members, secure loosely with 9 1/2" bolts, washers and lock nuts.

• Align the 6 Vertical members with holes in the lower frame, secure loosely with 9 1/2" bolts, washers and lock nuts.

• Align the 2 Top North-South members with upper holes in the vertical members, secure loosely with 9 1/2" bolts, washers and lock nuts.

• Align the 3 Upper Cross members with holes in the upper North-South members, secure with 9 1/2" bolts, washers and lock nuts.

• Tighten all bolts / nuts.

See Also

• LifeTrac III Solidworks CAD
• LifeTrac3 2D Fab Drawings