SistematikWork
Home / Manufacturing / How Sand Casting Works

How Sand Casting Works

Sand Casting: the route, the tolerances it holds, materials and design tips, with an indicative cost. One of 56 processes in the free finder.

CastingFamily
+/-1mmTypical tol.
5Route steps
131Parts in finder

Sand casting pours molten metal into a mould packed from sand around a pattern. When the metal solidifies the sand is broken away and the casting is cleaned up.

At a glance

When to use it, and when not

Best for

Large or complex metal shapes at low to medium volume, where tooling cost must stay low and some surface roughness is acceptable.

Watch for

Rough as-cast finish, loose tolerances, and porosity risk. Thin walls and very fine detail are hard to hold.

Step by step

The typical route

Raw material to finished part. Steps vary with material, volume and tolerance; this is the free route from the finder.

  1. Pattern & mold

    Make the pattern, then ram green or resin sand around it to form the cavity.
    Tooling Pattern   Tolerance -   Lead -

  2. Pour

    Melt the alloy and pour into the mold through the gating.
    Tooling Furnace   Tolerance -   Lead -

  3. Shakeout & clean

    Break out the casting, cut gates/risers, shot-blast.
    Tooling -   Tolerance -   Lead -

  4. Machine

    Mill/bore the functional faces and holes to spec.
    Tooling CNC   Tolerance -   Lead -

  5. Inspect

    Dimensional check plus NDT on critical castings.
    Tooling -   Tolerance -   Lead -
Precision

Tolerances it can hold

TYPICAL TOLERANCE IT CAN HOLD
+/-1mm typicalcoarsefine+/-1mm+/-0.1mm+/-0.01mm+/-0.005mm
Where this process typically lands. Tighter is possible with extra operations like grinding, at higher cost.
Materials

Materials it suits

GradeWhy it suits this
Gray iron (GG/GGG)Cheap, damping, easy to cast
Aluminium A356Light, good castability, heat-treatable
Carbon/alloy steelStrong, weldable
Design

Design tips

A few general pointers for Sand Casting. The full, part-specific DFM list is in the dossier.

  • Uneven wall thickness. Even the walls and add fillets.
  • No draft on vertical faces. Add 1 to 3 deg draft.
Cost

What it costs

Low tooling makes sand casting the cheapest route at low volume for medium-to-large metal parts; finish is rough so budget machining.

PER-PART COST vs VOLUME
one-offat volumeVolume per order, low to highCost per part
Per-part cost drops as volume spreads tooling and setup over more parts. The exact figures for your part at your volume, in your currency, are in the dossier.
MODEL EST.
$160 to 450 per part at 1 off
A rough ballpark only. The dossier gives should-cost at your exact volume and currency, with the full breakdown.
GET THE FULL DOSSIER

Everything you need to quote and source it

The free route above is yours. To actually put a number on this process and buy it well:

  • Should-cost at your exact volume in 12 currencies, with the material, processing, tooling and overhead breakdown
  • Who to source from, typical MOQ and lead time, and the exact RFQ checklist to send
  • A quote checker that tells you if a supplier quote is fair, and the red flags to watch
  • The full DFM list and a ready-to-send RFQ draft
Go Pro, every part, from $15/moOr unlock one part for $2

One part is $2, once. Pro is every part, plus the tracker, compare and sync. Cancel anytime.

Examples

Parts made by Sand Casting

131 parts in the finder use Sand Casting as their primary process. A sample, each with its own guide:

access coveradapteranchoraxle housingbedbellbench viceboiler sectionbollardbollard castbrake drumbrake rotorcannoncasingcast crankshaftcast manifoldconecounterweightcymbaldeck hardwaredumbbellengine partfire hydrantgearbox casegonggrategully gratingiron castingkettlebelllamp postmachine basemooring cleatplough framepropeller boatpulley wheelpump bodypump voluterudder fittingsheaveship propellerstovestreet furnitureweight plate
BEYOND MANUFACTURING

41 verified industrial-engineering tools

SistematikWork is a whole IE platform. Past the free finder, there are 41 ready Excel calculators, templates and CAD guides, each built from real coursework and checked against known values.

Manufacturing & OperationsQuality & ReliabilitySupply ChainProject & StatisticsEngineering Career
Browse all 41 toolsGet the complete toolkit
FAQ

Frequently asked questions

How is a part made by Sand Casting?
Sand casting pours molten metal into a mould packed from sand around a pattern. When the metal solidifies the sand is broken away and the casting is cleaned up. The typical route is: Pattern & mold; Pour; Shakeout & clean; Machine; Inspect. Large or complex metal shapes at low to medium volume, where tooling cost must stay low and some surface roughness is acceptable.
What does Sand Casting cost per part?
It depends on size, tolerance and volume. As a rough ballpark it starts around $160 to 450 per part at low volume and falls with quantity. The dossier gives should-cost at your exact volume and currency. Model estimates, not quotes.
What tolerance can Sand Casting hold?
Typically about +/-1 mm, tighter with extra finishing operations at higher cost.
What materials suit Sand Casting?
Common choices are Gray iron (GG/GGG) (Cheap, damping, easy to cast); Aluminium A356 (Light, good castability, heat-treatable); Carbon/alloy steel (Strong, weldable).
See the exact route and should-cost for your part

The free finder maps your part to its process and full route. Pro adds should-cost at your volume, sourcing and an RFQ draft.

Open the finderSee Pro