Fabricability Checklist

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This step should happen prior to the build.

General

Lean Analysis

  • Justice technique
  • Parts count minimization
  • 80% of function in 20% effort
  • Perform Product Ecology Review - efficiency occurs because parts and modules are interchangeable

Sourcing

  • All metal should in stock sizes if possible. IE. use 1”x4” instead of 1”x3.75”. This makes it easier to obtain for fabricators. Check material availability at a local shop.
  • All metal should be common alloys if possible.
  • Steel: A-36, 4130 Chromoly, 1018...
  • Aluminum: 6061, 3003
  • Materials should be accessible through common suppliers (McMaster Carr, Surplus Center, Grainger)

Parts Size

  • Individual parts should be reasonably simple, and consist of very few welded items, so if any parts break they’re easy to fix.
  • Are there any parts which are too big (>80 lbs, or awkward dimensions) for an average fabricator to easily handle? Can the size of these parts be reduced, without lowering function?

Geometry and Parts Fit

  • Are there bolts that can not be put in because of spatial conflicts?
  • Will cylinders fit throughout their full range of motion?
  • Will hoses or wires get stretched or broken if parts motion is involved?

Metals

Welds

  • Are all welds accessible to the welder?
  • Is the weld % correct?
  • Will welds cause warping? Will this cause issues?
  • Are all welds necessary?
  • Will welds adversely affect hardness?

Torching

  • Will torching adversely affect hardness?
  • Will torching warp the metal?

Hole sizing and placement

  • Tolerance all holes to be drilled, to insure there won’t be interferences. Factors include:
  • human error ( usually 1/32” - 1/16”)
  • Equipment error (depends on method of making holes- torching (>1/16”), Drilling (not much)
  • Are all holes accessible to drill or torch?
  • How will holes over 1” Diameter be made? Torch? Mag-Drill?
  • Mag-Drill:
  • Consider the cost of bits, and the possible drill depth of mag-drills.
  • If surface is recessed, will bit be able to reach?
  • Keep in mind that by drilling a center hole, you can magdrill 2x as thick material.
  • Torch:
  • Will torch be precise enough? Or will further machining ( such as reaming or boring) be necessary?

Machining

  • Is all machining necessary, or can precision be achieved thru other methods (IE match drilling)?
  • What is the expected amount of time reqiured for machining?

Precision

  • How will necessary precision (for things like shafting) be achieved? Is it possible?
  • What is the alignment procedure for achieving desired precision?
  • What is the estimated precision that will be achieved?