SAMPLE COSTING

The following is a cost estimation of a part for customers to roughly understand the cost of machining their parts by providing us with their drawings.

 

Description of Part:

The following part contains many features that are considered in the costing process.

The process of milling out this part requires OUTER as well as INNER CUTTING and has Intricate detail. It consist of

  • 2 circular through cut 
  • 4 drill 
  • 6 slot and
  • 3 triangular cut

Part has thickness = 6 mm

No. of pierces = 15

Total cutting length = 1400 mm

Machining cost according to Raw Material *

    Hylam: Machining cost: Rs.200.0, Process: CNC mill/routing
    Acrylic: Machining cost: Rs.150, Process: Laser Cutting
    Acrylic: Machining cost: Rs.250.0, Process: CNC mill/routing
    Nylon: Machining cost: Rs.250.0, Process: CNC mill/routing
    Plywood: Machining cost: Rs.200.0, Process: CNC mill/routing
    Aluminium: Machining cost: Rs.1200.0, Process: CNC mill/routing

*Considering Material is provide by the customer

Aluminium

Tool diameter = 3 mm

Feedrate = 150 mm/min

Depth of cut = 1 mm (max.)

Machining Time = 60 min

No. of passes = 6

Ply wood

Tool diameter = 3 mm

Feedrate = 300 mm/min

Depth of cut = 3 mm (max.)

Machining Time = 11 min

No. of passes = 2

[Costing charge calculation Includes Setup, Handling, Tear down, allowance time as per company policies]  

Other Processes

CNC Routing

Laser Cutting

Rapid prototyping (FDM)

 

Common Prototyping Materials

Light weight : Coroplast/FluteBoard, Foam board, cardboard box paper, Thermocol , PU foam etc.

Wood – Plywood, Balsa wood, MDF , OST ( One Side Teak), pine wood etc. 

Plastics – Acrylic, Polycarbonate, Nylon, PP,  ABS

Composite - Hylam, FRP, Carbon Fiber, Bakelite, PCB substrate etc. 

Non-ferrous - Aluminium, Copper, Brass.

 

Some of the prototyping materials like: coroplast, Cardboard box, Hylam etc. can be ordered online from STORES.EBAY.IN/ECNCSHOP


Various types of CNC router/milling jobs:


On a CNC machine  : the job type can vary from simple jobs to very complex jobs requiring multiple setup or tooling. Following is a list of various types of operations. Final manufacturing cost depends on the complexity of the job. 


  • Cut both Inner & outer geometry  ( Simplest to program and cut in mc. Can do nesting and finish job faster )
  • Cut only inner geometry when outer is already cut or shaped ( This can happen in case of rework in already completed job, cutouts on sides of enclosure boxes where cutout position and alignment of box edges is important, Or when standard raw material is available for required outer size etc. Such jobs need very careful clamping of workpiece such that it is aligned to machines axis and need significantly more programming and operator skills. Extra cost factor: more setup time per part)
  • Max job size ( Upto 2'x2' sz : machines are available easily even in small office/eCNCshops, but for bigger furniture size parts 4'x4' or 8'x4' sz mc needs a big factory setup. Extra cost factor: 3X )
  • Material type ( Soft materials can be cut deeper, but hard materials like metals take multiple low-depth-pass to complete, hence take more time )
  • Pocketing/Half-depth cutting ( Needs more programming skills and setup skills like flattening the bed surface to machine's axis etc. or use software like Gcode Ripper for surface height variation compensation. Extra cost factor: more programming time/cost, setup time/cost per part )
  • 3D surface design cutting ( need more programming and CAM sw and  operation skills. Extra cost factor: more programming time/cost per part )
  • Multiple tool cutting ( If job involves small inner holes/features and large outer periphery, need to do tool change in between to accomodate. Extra cost factor: more programming time and setup time per part )
  • Intricate or small profiles ( Say job perimeter is same. But when cutting with small dia ( say 1mm) tool: risk of tool breakage is higher . So charges will be more compare to same perimeter job cut with bigger dia tool ( say 3mm or 6 mm ). Extra cost factor: Tooling cost )
  • Double side cutting ( Features on both top & bottom side of component. Need programming and operational skills to re-align the part after flipping. Extra cost factor: more setup time per part  ). 
  • Multiple setup/Operation involved ( Side holes, tapping, CSK, Counterbore etc. Extra cost factor: more programming time and setup time per part  )